By S. Angir. Shaw University.
Swelling and inammation at the anal verge Pathophysiology may form a sentinel pile (haemorrhoid) generic fildena 25mg visa. Initially prolapse only occurs on defecation with sponta- neous return; however purchase 150 mg fildena visa, with time the prolapse becomes Clinical features more permanent buy fildena 100 mg overnight delivery. Thesentinelpilemaybevis- Clinical features ible on examination purchase fildena 50 mg overnight delivery, rectal examination is very painful There is often discomfort on passing stool possibly with and often impossible. Examination under anaesthesia bleeding and mucus due to inammation of the pro- (proctoscopy/sigmoidoscopy) allows diagnosis. Patients often present with an abscess, the incision of which completes the stula. Patients with a completed Management stula present with a discharging sinus that causes lo- Primaryanalssuresmayhealspontaneously. An incision is made into the perianal skin on one side of the anal canal Investigations and the internal sphincter is divided without entering Proctoscopy may reveal the internal opening with a exi- the lumen. Fistula-in-ano Management Denition Primary stulas are laid open to granulate and epithe- A stula is an abnormal communication between one lialise. Associations include inammatory bowel disease, tuberculosis and Denition carcinoma of the rectum. A sinus of the natal cleft containing hair that often be- 1 Low anal stula is the commonest form with a com- comes infected. Aetiology/pathophysiology 2 High anal stulas have a track which extends above It is thought that sinuses arise from penetration of hairs the pectinate line below the anorectal ring. A post anal cle bres of the internal and external anal sphincter pilonidal sinus typically occurs around 2 cm posterior surround the rectum. In both low and high stulas to the anus and extends superiorly and subcutaneously the track of the stula may pass through the bres for about 2 5 cm. Pathophysiology Goodsall s rule states that if the stula lies in the anterior Anorectal abscess half of the anal area then it opens directly into the anal canal, while if a stula lies in the posterior half of the Denition canal then it tracks around the anus laterally and opens Anorectal abscesses may occur as perianal, ischiorectal into the midline posteriorly. Sex Management 2M : 1F Perianal and ischiorectal abscesses are drained under general anaesthetic and de-roofed by making a cruci- Aetiology ate incision and excising the resultant 4 triangles of skin. In the majority of patients there is no apparent cause for 25% of abscesses recur. Vascular disease of the bowel Pathophysiology Infection of an anal gland may cause a tracking down Intestinal ischaemia to form a perianal abscess, or tracking out to form a Intestinal ischaemia results from a failure of the blood ischiorectal abscess, or upwards to produce a high inter- supply to the bowel. Three underlying patholo- gies are in operation resulting in a number of clinical Clinical features r entities all with three possible outcomes (see Fig. Perianal abscess is common and presents in well pa- tients with an acute tender swelling at the anal verge. Patients Localised bowel pathology may result in focal area of have signicant systemic upset. These are conrmed twists on itself usually around a brous peritoneal band on barium studies and require resection. Investigations Pathophysiology A barium enema can be used to show oedema or mu- The ischaemia results from venous infarction due to cosal sloughing. Mesenteric angiography will external pressure resulting in venous congestion and demonstrate the stenosis or occlusion. Management The condition generally is self-limiting within a few days Clinical features/management with uncomplicated cases managed conservatively. If blood ow is not restored, a progression to in- farction and necrosis necessitates bowel resection. Chronic intestinal ischaemia Denition Slow progressive ischaemia of the gut due to atheroma Ischaemic colitis generally occurring in the elderly. Denition Ischaemia of the colon due to interruption of its blood Aetiology supply. Risk factors: r Fixed: Age, sex, positive family history, familial hyper- Aetiology In most cases the underlying cause is thrombosis of the lipidaemia. Pathophysiology In around half the ischaemia is transient with damage Pathophysiology connedtothemucosaandsubmucosa. Thesplenicex- Progressive atheroma occludes the lumen of the vessels ure is most often affected due to the territories of the causing reduced blood ow. If the blood supply is not depends on the position and degree of occlusion and the restored, ischaemia progresses to gangrenous ischaemic presence of collateral blood supply. Clinical features Patients describe pain occurring after food, weight loss, Clinical features malabsorption and signs of vascular disease. The patient presents with lower abdominal pain, nausea, vomiting and bloody diarrhoea. There is lower abdom- Investigations inal tenderness and guarding in the lower abdomen. Microscopy Management There is ischaemic loss of mucosa, ulceration and later Surgical revascularisation depends on the results of an- healing with oedema and inammatory inltrate. Denition Complete necrosis and gangrene of the midgut resulting Aetiology from cessation of blood ow in the superior mesenteric r Squamous carcinoma accounts for more than 90% of artery. These usually occur in the middle third of the oesophagus although the lower third may also be af- Clinical features fected. Aetiological factors include high alcohol con- There may be a preceding history of non-specic symp- sumption, smoking and chewing betel nuts. Signs of acute intestinal failure include ab- affects the lower third of the oesophagus particularly dominal tenderness, guarding, loss of bowel sounds and the gastrooesophageal junction possibly following ep- rigidity, due to perforation. Calcication within the abdominal aorta may be evident r Familial forms have been noted. Gas lled, thickened, dilated bowel loops and free gas within the peritoneal cavity due to Pathophysiology perforation may also be seen. Following adequate resuscitation laparotomy and resec- tion(whichmaybemassive)arerequired. Patients may present with progressive dysphagia, but of- Asecond look laparotomy can be performed 24 hours tenpresent late with weight loss, anaemia and malaise. If Barium swallow demonstrates an apple core defect or the patient survives they have considerable malabsorp- stricture without proximal dilatation. In the absence of metastases endoscopic ultrasound is useful to assess operability. Management r Wherever possible surgical resection is the primary Age treatment with those occurring in the lower third Rare below the age of 40 years. Neoadjuvant Denition chemotherapy with cisplatin and 5-uorouracil (5- Malignant tumour of the stomach. Sex Prognosis 2M > 1F Surgical resection carries an operative mortality of up to 20%. Benign gastric tumours Aetiology Denition Pre-malignant conditions include chronic atrophic gas- Benign tumours and polyps of the stomach. These can tritiswithintestinalmetaplasiaandadenomatouspolyps be divided into epithelial and mesenchymal derived tu- of the stomach. Hyperplastic polyps are common overgrowths of gas- r Dietary carcinogens possibly including nitrates and tric mucosa often resulting from the healing of an alcohol. Pathophysiology They have a signicant risk of malignant change most Gastric adenocarcinomas are derived from mucus se- likely in large polyps. Tumours may be of three types: Mesenchymal derived benign tumours: r Ulcerating (most common) with appearance similar r Leiomyomas appear as mucosal or intramural nod- to benign ulcers but with raised edges and no normal ules. Most benign tumours are asymptomatic and found on r Inltrating when brous tissue causes a rm non- endoscopy or barium meal. Rarely bleeding or obstruc- distendable or linitis plastica (leather bottle) stomach. Spread may be direct invasion to the liver and pancreas, Management transcoelomic spread resulting in a malignant ascites Allsuspiciouspolypsrequireexaminationbyendoscopic and ovarian Krukenberg tumour, lymphatic spread to excision biopsy, multiple polyps may require gastric re- regional and distant lymph nodes (Virkow s node) and section. There may be dyspepsia or Tumours arising in the mucosa associated lymphoid tis- haematemesis. Dermatomyositis and acanthosis nigricans may be manifestations of an underlying gastric malig- Clinical features nancy. Patients present similarly to gastric adenocarcinoma with non-specic weight loss, anaemia and malaise and Microscopy associated epigastric tenderness. Symptoms may be mild Histologically gastric adenocarcinomas may have an in- despite a large tumour mass. Investigations Diagnostic testing usually involves an endoscopy and Investigations biopsy,whichmaybeprecededbyabariummeal. Anaemia is a non-specic Management nding and liver metastases may cause a rise in liver Lymphoma often responds to H. Patients who do not respond to, or who relapse fol- Treatment of choice is surgical resection wherever pos- lowing eradication therapy are treated with single agent sible. Combination chemotherapy Prognosis may be used in disease not amenable to surgery. Overall Small intestine lymphoma 5-year survival in the United Kingdom is around 10% Denition due to late presentation. Anon-Hodgkin lymphoma which occurs within the small bowel particularly in the ileum. Coeliac disease predis- System Symptom Frequency (%) poses toaTcelllymphoma,treatmentwithglutenfree Skin Flushing 85 diets may reduce the risk. Octreotide (somato- Carcinoid tumours of the intestine statin analogue) relieves diarrhoea and ushing and Denition may reduce tumour growth. Large bowel neoplastic polyps Denition Aetiology/pathophysiology Apolyp is dened as a tumour attached by a stalk to the Carcinoid tumours most commonly occur in the ap- surface from which they arise. Clinical features Age Most lesions are asymptomatic although appendix car- Sporadic cases increase with age. Carcinoid syndrome occurs in 5% with liver metastases, the fea- Aetiology/pathophysiology tures of which (see Table 4. Most colorectal cancers arise from adenomatous polyps r Tubular polyps account for 90% and consist of glan- with a median transition of 20 years. Ulcerative colitis is dular tubules with a brovascular core covered by a associated with an increased incidence. Clinical features Pathophysiology Most are asymptomatic but they may cause bleeding and Colonic cancer occurs in the sigmoid colon and rec- diarrhoea. The tumour All neoplastic polyps are pre-malignant, low lesions may spreads by direct inltration into the bowel wall and cir- prolapse through the anus. Subsequent invasion of the blood and lymphatics results in distant metastasis most fre- Management quently to the liver. Tubular polyps are resected endoscopically, villous le- sions require transmural excision or formal resection. Clinical features Presentation is dependant on the site of the lesion, but in Prognosis general a combination of altered bowel habit and bleed- There is a 30 50% risk of recurrence therefore surveil- ing with or without pain is reported. Up to a third of lance with 3 5 yearly colonoscopy in patients under 75 patients present with obstruction, or perforation. Examination may reveal a mass (on abdominal palpation or rectal examination), ascites Large bowel carcinoma and hepatomegaly. Macroscopy/microscopy Raised red lesions with a rolled edge and central ulcera- Incidence tion. Investigations Age r Endoscopic examination of the large bowel with Average 60 65 years.
Glycoproteins that are allergenic have molecular weights of 10 generic 50 mg fildena with visa,000 to 67 discount fildena 25mg online,000 daltons purchase fildena 50mg. They are water soluble fildena 100mg sale, predominantly heat stable, and resistant to acid and proteolytic digestion ( 46). Although many foods are potentially antigenic, the vast majority of food allergies involve only a few foods ( 47). The combined results of double-blind placebo-controlled food challenges performed in the United States (primarily in children) showed that eight foods were responsible for 93% of reactions (39). The prevalence of specific allergens may vary for different countries, depending on exposure patterns. Allergens found commonly in children but not in adults (eggs, soy, milk and wheat) are usually outgrown with strict elimination for 1 or more years (48), although evidence of IgE antibodies may persist ( 49). Those with histories of severe reactions may take longer to develop clinical tolerance, up to several years (48,50). The others [peanuts ( 51), tree nuts, crustacea (52), and fish (53)] tend to be lifelong and thus are common to both populations. Some whey proteins found in milk are denatured by heating and routine processing, whereas others are rendered more allergenic (54). Fish allergens may be changed with the canning process, and a patient who cannot tolerate fresh fish may tolerate canned tuna and other processed fish (55). Beef has been reported to have heat-labile allergens; therefore, cooking may abrogate sensitivity ( 56). Peanut allergen is remarkably resistant to any kind of processing, retaining its allergenicity ( 57). Peanut oil has been tolerated by 10 peanut-allergic individuals ( 58), but there have not been adequate studies ensuring its safety. Crustacea also show considerable cross-reactivity ( 65) but the clinical significance remains unknown due to a lack of controlled food challenges. These result in smooth muscle contraction, vasodilation, microvascular leakage, and mucus secretion. Cytokines are also generated over several hours and thought to play a significant role in the late-phase response. Eosinophils, monocytes, and lymphocytes are recruited to the area affected in the late-phase response and release a variety of cytokines and inflammatory mediators. Clinical manifestations of IgE-mediated food allergy depend on the organ systems involved. Reactions can be isolated, in combination, or as part of a generalized anaphylactic reaction. Cutaneous Manifestations Cutaneous manifestations are the most common reaction, but the absence of skin symptoms does not exclude food-induced anaphylaxis ( 12). These cutaneous reactions range from acute urticaria or angioedema to a morbilliform pruritic dermatitis. In one study of 210 children evaluated and followed to determine a relationship between food allergy and exacerbations of their atopic dermatitis, 62% of children had a reaction to at least one food. Urticaria was rare, and cutaneous manifestations were predominantly erythema and pruritus leading to scratching and exacerbation of the atopic dermatitis. Sampson and Broadbent reported an increase in histamine releasabililty in patients with atopic dermatitis who repeatedly ingest a food allergen ( 72). Gastrointestinal Manifestations Gastrointestinal symptoms are the second most frequently noted manifestation of food allergy. Clinical presentations include nausea, vomiting, diarrhea, and abdominal pain and cramping. These symptoms may occur alone or in combination with symptoms from other organ systems. Studies in humans have elucidated some possible mechanisms but there is still much that is not known. There is considerable evidence that many of these symptoms result from the activation of mast cells (73). The oral allergy syndrome is considered to be a form of contact urticaria with symptoms resulting from contact of the food allergen with the oral mucosa. Symptoms include pruritus with or without angioedema of the lips, tongue, palate, and posterior oropharynx. It is associated with the ingestion of fresh fruits and vegetables and is the result of cross-allergenicity between the fruit or vegetable and some pollen. However, ingestion of celery tuber (celery root), which cross-reacts with birch pollen, may cause more severe systemic symptoms in pollen-allergic patients ( 83). This may be explained by the presence of both heat-labile and heat-stable proteins ( 86). Pruritus of the mouth and lips, however, can be the initial symptoms of more severe food allergy, especially in those foods most commonly implicated in food anaphylaxis (i. Therefore, in the setting of known food anaphylaxis, these symptoms should not be trivialized. Often this is associated with peripheral eosinophilia and rarely may involve other organs. Involvement of the submucosal and muscular regions is more common in the prepyloric region of the gastric antrum and the distal small intestine ( 89). These patients also may have symptoms of gastric outlet obstruction, a mass lesion with epigastric tenderness, and even perforation of the intestinal wall ( 87,90). Rarely, eosinophilic infiltration involves the serosal surface, presenting with prominent ascites ( 87,88 and 89). Patients in whom eosinophilic gastroenteropathy is thought to be IgE mediated (approximately 50% of adult cases) tend to have a history of atopy, including asthma and allergic rhinitis, and tend to have elevated IgE levels. These patients tend to have multiple food intolerances and positive skin test results to multiple foods ( 91). Repeated degranulation of mast cells resulting from multiple food allergies is thought to be the cause of this disease in these atopic patients. Food-induced symptoms are thought to more common in children, although the prevalence is not known (92). Symptoms commonly occur in the late afternoon or evening (after feeding) and last for several hours. Several double-blind cross-over trials have supported IgE-mediated food hypersensitivity as a mechanism in a minority of cases (94,95 and 96), in both breast-fed and formula-fed babies. However, the syndrome is poorly defined and is likely multifactorial with no treatment that consistently relieves symptoms. True food allergy is thought to be responsible for only 10% to 15% of cases ( 97). Respiratory Manifestations Respiratory manifestations of food allergy usually present as part of a generalized anaphylactic reaction. Symptoms include sneezing; rhinorrhea; ocular, otic, and palatal pruritus; bronchospasm; and laryngeal edema. Isolated airway symptoms as a manifestation of food allergy are exceedingly rare ( 100). Symptoms occur 1 to 8 hours after ingestion of the allergen, leading to a clinical picture of chronic diarrhea, eosinophilia, and malabsorption. Jejunal biopsy reveals partial villous atrophy, lymphocytosis (103), and plasma cells containing IgM and IgA ( 103,104). Skin-prick test results are characteristically negative, supporting the idea that the immunologic mechanism is not IgE mediated. However, some investigators propose a localized IgE mechanism with resultant mast cell degranulation ( 105,106). In addition, some children have a component of IgE sensitivity to milk or soy as well and there is increased atopy among family members. Resolution of symptoms occurs within 72 hours after elimination of the allergen, but diarrhea may persist longer due to the secondary development of disaccharidase deficiency. Rechallenge 3 is hallmarked by a recurrence of symptoms within 1 to 8 hours, fecal leukocytes and erythrocytes, and an increase in peripheral blood leukocytes by 3,500 cells/m (101). Food-Induced Colitis Food-induced colitis is similar to enterocolitis, with the same allergens being responsible milk and soy ( 107,108 and 109). It is also seen in infants exclusively breast-fed for reasons described earlier ( 111). It appears in the same age group, but there is no diarrhea or marked dehydration, and children appear less ill ( 108,109). Hematochezia or occult blood in the stools is the most common clinical finding ( 109,110,112). Depending on the extent of involvement, sigmoidoscopy findings range from areas of patchy mucosal injection to severe friability with bleeding and aphthous ulcers ( 110,111). Colonic biopsies characteristically reveal eosinophilic infiltrate in the lamina propria and crypt epithelium with destruction of crypts; neutrophils are found in severe lesions (109,111). Blood loss usually resolves within 72 hours of discontinuing the allergen, but resolution of mucosal lesions may take up to 1 month. Symptoms usually present in the first few months of life and are nonspecific with regard to the etiology. They range from steatorrhea to protracted diarrhea, poor weight gain, and failure to thrive (113). In the small intestine, there are frequently areas of villous atrophy interspersed with areas of normal mucosa, referred to as a patchy enteropathy (113,114). The epithelium is hypercellular with a predominant mononuclear cell infiltrate and few eosinophils. Challenge with the allergen does not produce immediate symptoms but may take days to weeks (113). Likewise, resolution of symptoms after antigen elimination is slow, with resolution of lesions requiring 6 to 18 months ( 113). Celiac Disease Celiac disease, also known as gluten-sensitive enteropathy or celiac sprue, is characterized by malabsorption secondary to gluten ingestion ( 115,116). The small intestine is involved with characteristic lesions (117), which resolve totally with elimination of gluten. Less severe disease may go unrecognized, not being diagnosed until adulthood ( 118). The small intestine is involved to varying degrees, with the proximal portion being involved most often ( 119). Clinical symptoms are those of malabsorption and are indistinguishable from other causes of malabsorption. The severity of symptoms correlates directly with the amount of intestine involved. Symptoms may be mild, such as ill-defined, vague symptoms of not feeling well, or patients may present with anemia secondary to vitamin B 12 or folate malabsorption. There is shortening of the microvilli and flattening of the villi, frequently giving them a fused appearance ( 121). The lamina propria is hypercellular, with a predominance of lymphocytes and plasma cells ( 118,121).
Guidelines for prevention of stroke in patients with ischaemic stroke or transient ischaemic attack discount fildena 100mg with amex. Rehabilitation 50 mg fildena visa, prevention and management of complications generic fildena 150mg without prescription, and dis- charge planning fildena 50mg overnight delivery. Many years of productive life 173 Conclusions and recommendations are lost, and many people have to suffer years of disability after brain injury. In addition, it engen- ders great economic costs for individuals, families and society. The world is facing a silent epidemic of road trafc accidents in the developing countries: by 2020, road trafc crashes will have moved from ninth to third place in the world ranking of the burden of disease and will be in second place in developing countries. Systematic triage of patients can lead to important economic savings and better use of scant hospital resources. More standardized pre-hospital and in-hospital care, to minimize secondary brain injury, can improve outcomes substantially. Acceleration and deceleration forces may disrupt the nervous tissue and blood vessels of the brain. The intermediate category, moderate head injury, implies a mortality rate of 2 5%. Further classication of the brain injury is made in order to evaluate prognosis, identify pa- tients at risk for deterioration and choose appropriate observation and treatment. Someone who opens his eyes only after painful stimulation, utters only incomprehensible sounds and withdraws his hand only after pinching will be given a score of 8. A fracture detected on the skull X-ray images indicates an increased risk of deterioration, and the patient will need admission. In spite of these reservations, it can be interesting and informative to compile data from different parts of the world. Some of the differences could be as- cribed to variations in study years, inclusion criteria and research methods. Therefore, incidence rates such as 546 per 100 000 per year in Sweden and 91 per 100 000 per year in Spain must be interpreted with caution. Data from many parts of the world consistently show a peak incidence rate in children, young adults and elderly people. Information on how sequelae develop (diminish or increase) over time is scarce (8); better data on prevalence would certainly be useful for improved planning of rehabilitation needs. The average European pre-hospital case-fatality rate was 8%, while the in-hospital rate was 3%, i. Mortality rate per 100 000 population per year is more informative than the case-fatality rate. It has been suggested that heavy alcohol abuse may explain the persistent and high mortality rate in Finland (11). Disability Traumatic brain injury is the leading cause of disability in people under 40 years of age. Disability can be classied in a simple fashion using the Glasgow Outcome Scale (see Table 3. Most patients (90%) had sustained a mild head injury, while a few had suffered moderate (5%) or severe (3%) brain injury. Even among young patients with mild injuries and a good pre-injury status, one third failed to achieve a good recovery. Mostly, patients with severe disability will have a combined mental and physical handicap. It may be transitory, subsiding after a month or so, but may persist in many cases. The persistently vegetative patient needs articial nutrition and hydration and will have a markedly reduced life span, i. In some cases, complicated ethical and legal discussions arise about the purpose of continuing life-sustaining treatment. These variations must be taken into account by health planners who design prevention programmes. Every day about 3000 people die and 30 000 people are seriously injured on the world s roads, nearly half of them with head injuries. Most of the victims are from the low income or middle income countries, with pedestrians, cyclists and bus passengers bearing most of the burden (12). Fatality rates among children are six times greater in developing countries than in high income countries. Terms such as a public health crisis and a neglected epidemic have been used to describe this growing problem (13). People 70 years or older have a relatively high incidence of head injuries, and in these patients falls are the most common cause. These patients can be dismissed after a short clinical examination and adequate information, since their risk of further problems will be very low, i. Before dismissal, they deserve brief information, preferably written, about: warning signs indicating possible complications; how normal and mild symptoms are expected to develop; how to resume normal daily activities. Therefore, a closer examination may be required to identify the individuals with the highest risk of developing complications. Patients who need special attention are those with: decreasing level of consciousness; neurological decit; epileptic seizure; decient blood coagulation; age >60 years; alcohol abuse. A fracture will indicate a higher risk of deterioration and admission is necessary for a short time of observation. Airway obstruction and falling blood pressure are the acute threats to the vulnerable brain-injured patient. On admission, life-supporting measures should be continued, in accordance with Advanced Trauma Life Support recommendations (22). In the United Kingdom, the mortality in patients with epidural haematoma declined progres- sively from 28% to 8% after the introduction of national guidelines for the early management of head injury (22). The guidelines clearly indicate how patients at risk should be identied and managed before progressive brain damage occurs. At the same time, reduced hospital costs 170 Neurological disorders: public health challenges were obtained through shortened length of stay, from an average of 21. There is strong evidence of benet from formal interventions, particularly more in- tensive programmes beginning when the patients are still in the acute ward. The balance between intensity and cost effectiveness has yet to be determined (24, 25). The importance of rehabilitation is consistently underestimated, not least because of its cost. It is a regrettable truth that this part of the treatment lacks the drama of the primary treatment and is consequently more difcult to fund. This Centre receives patients from all over the form of physical and occupational therapy. Nutritional and country; it is classied as a tertiary care hospital and of- feeding requirements are evaluated and installed. Families fers highly specialized medical care to the population on receive psychological support and advice, orientation in at- an inpatient and outpatient basis. Home visits are scheduled in order to offer advice sisting of two physicians (specialized in medical rehabilita- on eliminating architectural barriers and to give training to tion), a head nurse, an occupational therapist, a physical family members in their own environment. Once patients have recovered com- the team makes rounds to the inpatients and meets six out- plete consciousness, cognitive sequelae are evaluated and patients in order to assess them throughout the subacute treated and physical sequelae are further evaluated and process of their rehabilitation; active participation of the treated. Both can be done as inpatients or outpatients, de- families is encouraged at all stages of the rehabilitation pending on the distance between the Centre and the pa- process. The patient population is composed of patients who Patients and their families are supported throughout their were over 12 years of age at the moment of the lesion and subacute and chronic phases of recovery by all team mem- who sustained severe traumatic head injuries, as well as bers, and services are offered when needed in an open patients with non-traumatic brain damage. By 2020, it is estimated that road trafc crashes will have moved from ninth to third place in the world ranking of the burden of disease and will be in second place in developing countries. To quote an article in the British Medical Journal: sleepiness among drivers may account for nearly a fth of road trafc crashes. Similarly, if the international public health community continues to sleep through the global road trauma pandemic it will be accountable for many millions of avoidable deaths and injuries (12). Her former She sustained a severe head injury in 1999, which did not subordinates made fun of her failure, which depressed her produce any physical limitation but severely affected her further. When last seen, Vera was receiving treatment for memory and, to a lesser extent, speech. After evaluation it severe depression, but insisted she wanted to recuperate was evident that Vera had important intellectual limitations. Vera refused to change her job; memory impairment (as in Vera s case), attention problems, she asked the team not to visit her superiors and tried in mild to severe intellectual deciency, lack of concentration vain to maintain her position at work without letting any- and limited ability to learn can result in impossibility body know her condition. After some months she eventually to return to work, affect emotional stability, and limit per- resigned from her job, very depressed because her staff formance at work and at home. All of these problems will no longer trusted her and had lost respect for her author- affect the person s emotional status, as well as his or her ity she constantly made mistakes, could not remember family and friends. They should also know that road trafc injuries are preventable and that some measures are very effective. With reliable data about the epidemiol- ogy of the war on the roads, a sense of urgency can be established among policy-makers and effective preventive measures can be designed that are tailored to local trafc conditions and take account of regional data on external causes and risk factors (12). Examples are physical measures to separate motor vehicles from pedestrians, speed bumps, speed cameras, strict speed limits and alcohol check-ups. Educational programmes may be a useful supplement in adults, but there is no evidence that education of pedestrians reduces the risk of motor vehicle collisions involving children on foot (12). Community-based activities (such as American Association of Neurological Surgeons Think rst and Group at risk designed programmes), as well as interaction with motor vehicle com- panies, are important elements in prevention programmes. Realities in both developed and de- veloping countries must be taken into account to make sure the programmes will be acceptable and efcient. Improved medical treatment would not have much impact in such cases, since most gunshot wounds to the head are fatal. There is a need for more efcient prevention, starting with specic legislation to regulate the use of rearms (16). In fact, a large propor- tion of moderately or severely head-injured patients will have concomitant injuries of the spine, chest, abdomen or extremities. Such studies should range from logistics, quality of life studies, pathophysiology, etc. Health policy-makers, doctors, nurses and paramedics should be proud of their achievements and join forces to organize a worldwide ght against the silent and neglected epidemic of traumatic brain injury. This should be a joint effort between different government agencies, medical societies, motor vehicle manufacturers and nongovernmental organizations. Disability in young people and adults one year after head injury: prospective cohort study. Management of brain-injured patients by an evidence-based medicine protocol improves outcomes and decreases hospital charges.
Tetrachlorophthalic anhydride is a chemical substance that produces immediate and late asthmatic reactions in a small percentage (<2%) of exposed workers generic fildena 150 mg online. Cigarette smoking rather than a history of atopy appeared to be the predisposing factor ( 267) generic fildena 25 mg on-line. Numerous other chemical and biologic materials generic fildena 100 mg online, mainly industrial or occupational order 50 mg fildena overnight delivery, have been implicated more recently in human asthma. It is important from practical and heuristic viewpoints to determine if the mechanisms of asthma are caused by IgE mediation, nonspecific mediator release, or irritating phenomena that are thought to act by nociceptive reflex parasympathetic stimulation. Methods used to study suspected substances include epidemiologic data, bronchoprovocation, and the ability to block bronchoprovocation by disodium cromoglycate or atropine, as well as attempts to identify antigen-specific IgE or IgG by techniques previously described. Some examples of inhalants to which reactions are thought to be immunologically mediated are salts of platinum ( 269), chrome, and nickel (272). Plicatic acid is able to activate complement and generate chemotactic activity from pooled human serum, but the role of this mechanism, if any, in red cedar asthma has not been determined (274). Only 50% of those affected eventually recover after terminating exposure to plicatic acid. Other examples of occupational asthma occur among snow crab processing workers and individuals who use solder. In the latter case, colophony, a component of flux, is the asthmagenic material (275). Asthma exacerbated by direct irritation of the bronchi is common in clinical practice. Odors from perfumes and colognes, vapors from petroleum products and organic solvents, and fumes from tobacco and cooking oils cause coughing and wheezing in many patients. Metabisulfites, sulfiting agents used as preservatives agents used as preservatives and clearing agents, may act as a nonspecific irritant ( 276). The fumes are created when polyvinyl chloride is cut with a hot wire in the process of wrapping cuts of meat. Multiple epidemiologic studies have demonstrated a correlation between levels of common outdoor air pollutants and hospital admissions or emergency room visits ( 277,278). However, these epidemiologic studies are limited by confounding factors, including air temperature and levels of other outdoor aeroallergens. For this reason, experiments also have been performed under controlled conditions involving short exposures to individual pollutants. Ozone is generated by the action of ultraviolet light on precursor pollutants from such sources as automobiles and power plants. A few studies have suggested that ozone increases allergen responsiveness associated with both asthma and allergic rhinitis. Nitrogen oxides from car emissions also may play a role, although the evidence in controlled exposures is less convincing than for ozone ( 281). One study attempted to sensitize atopic individuals to keyhole limpet hemocyanin, a protein isolated from a marine mollusk, with no known cross-reactive antibodies in humans. Sulfur dioxide is a product of soft coal burned for industrial use and is the substance most closely correlated with respiratory and conjunctival symptoms. Incompletely oxidized hydrocarbons from factories and vehicular exhaust make up the particulate matter visible in any highly populated or industrial area. Carbon monoxide impairs oxygen transport, but its concentration in ambient polluted air is probably important only for patients with marginal respiratory reserve. Most formaldehyde symptoms occur in mobile homes, where large amounts of particle board have been used in a relatively small enclosed space. Concentrations of 1 to 3 ppm or higher may cause mucous membrane symptoms in some individuals; atopic persons may react at lower concentrations. Experimentally, formaldehyde can be rendered immunogenic by the formation of formaldehyde protein complexes. However, it has not been proven that these complexes cause IgE- or IgG-mediated disease, nor has it been proven that inhalation of formaldehyde leads to the formation of formaldehyde protein complexes (284). The term sick building syndrome refers to outbreaks of acute illness among workers in a particular building or area of building. Most buildings in which this has been reported have been energy efficient, with little direct outside air exchange. The symptoms most commonly involve the conjunctivae and respiratory tract, with additional nonspecific complaints such as headache, fatigue, and inability to concentrate. Except for unusual instances of contamination with microorganisms (such as Legionella) or of hypersensitivity pneumonitis, the outbreaks have not resulted in serious morbidity or permanent disability. The cause in more than half of the instances studied has been inadequate ventilation, and symptoms abated when corrective measures were taken. A study in Montreal revealed that workers with Alternaria exposure and sensitivity were more likely to have respiratory symptoms. Exposure was correlated with less efficient filtration systems and could represent a significant avoidable exposure for some individuals ( 285). Specific contamination from inside the building has been observed in 17% of sick buildings. Contaminants have included methyl alcohol, butyl methacrylate, ammonia, and acetic acid from various office machines; chlordane (an insecticide); diethyl ethanolamine from boilers; rug shampoos; tobacco smoke; and combustion gases from cafeterias and laboratories. Alkanes, terpenes, benzenes, and chlorinated hydrocarbons also have been identified in investigations of indoor air. In some instances, indoor contamination may occur from outside of the building: for example, the intake of automobile exhaust from an adjacent parking garage. Formaldehyde is released as a gas ( off-gassing ) from a variety of sources such as foam insulation, new furniture, and carbonless carbon paper. The role of tobacco alone in the sick building syndrome is not clear when adequate ventilation is present, however. Finally, the role of psychogenic suggestion in the sick building syndrome should be considered. Such instances have been reported, based on a variety of inconsistencies in the affected population and the lack of objective findings in both the patients and the building. Immunochemical quantitation of airborne short ragweed, Alternaria, antigen E, and Alt-I allergens: a two-year prospective study. Concentrations of major grass group 5 allergens in pollen grains and atmospheric particles: implications for hay fever and allergic asthma sufferers sensitized to grass pollen allergens. Effect of thunderstorms and airborne grass pollen on the incidence of acute asthma in England, 1990 94 [see comments]. Protease-dependent activation of epithelial cells by fungal allergens leads to morphologic changes and cytokine production. Airborne concentrations and particle size distribution of allergen derived from domestic cats ( Felis domesticus). Measurements using cascade impactor, liquid impinger, and a two-site monoclonal antibody assay for Fel d I. Airborne ragweed allergens: association with various particle sizes and short ragweed plant parts. Airborne allergens associated with asthma: particle sizes carrying dust mite and rat allergens measured with a cascade impactor. Recognition of pollen and other particulate aeroantigens by immunoblot microscopy. Guidelines for the preparation and characterization of high molecular weight allergens used for the diagnosis of occupational lung disease. Report of the Subcommittee on Preparation and Characterization of High Molecular Weight Allergens. Quality assurance and standardization of allergy extracts in allergy practice [see comments]. Specific histamine release capacity of peptides selected from the modelized Der p I protein, a major allergen of Dermatophagoides pteronyssinus. Quantitative immunoelectrophoretic methods as a tool for the analysis and isolation of allergens. Cloning of Amb a I (antigen E), the major allergen family of short ragweed pollen. Antigen E content of pollen from individual plants of short ragweed ( Ambrosia artemisiifolia). Recombinant expression and reactivity with T cells from ragweed allergic patients. Analyses by leukocyte histamine release and the radioallergosorbent test and determination of cross-reactivity. Skin reactivity to purified pollen allergens in highly ragweed-sensitive individuals. Sequence of the proteinase-inhibitor cystatin homologue from the pollen of Ambrosia artemisiifolia (short ragweed). Isolation and characterization of Russian thistle ( Salsola pestifer) pollen allergens. The IgE-binding epitopes of rPar j 2, a major allergen of Parietaria judaica pollen, are heterogeneously recognized among allergic subjects. Characterization of a dodecapeptide containing a dominant epitope of Par j 1 and Par o 1, the major allergens of P. Cellular localization of water soluble, allergenic proteins in rye-grass ( Lolium perenne) pollen using monoclonal and specific IgE antibodies with immunogold probes. Variability of crossreactivity of IgE antibodies to group I and V allergens in eight grass pollen species. Study of the epitope structure of purified Dac G I and Lol p I, the major allergens of Dactylis glomerata and Lolium perenne pollens, using monoclonal antibodies. Cloning, sequencing and immunological characterization of Dac g 3, a major allergen from Dactylis glomerata pollen. Characterization of Phl p 4, a major timothy grass (Phleum pratense) pollen allergen. Molecular cloning and immunological characterisation of Cyn d 7, a novel calcium-binding allergen from Bermuda grass pollen. IgE antibodies to recombinant pollen allergens ( Phl p 1, Phl p 2, Phl p 5, and Bet v 2) account for a high percentage of grass pollen-specific IgE. A study with 17 whole pollen extracts and purified natural and recombinant major allergens. Monoclonal antibodies against birch pollen allergens: characterization by immunoblotting and use for single-step affinity purification of the major allergen Bet v I. The gene coding for the major birch pollen allergen Betv1, is highly homologous to a pea disease resistance response gene. Molecular cloning and characterization of a birch pollen minor allergen, Bet v 5, belonging to a family of isoflavone reductase-related proteins. Purification and characterization of an 18-kd allergen of birch ( Betula verrucosa) pollen: identification as a cyclophilin. Isolation and partial characterization of the major allergen from Japanese cedar ( Cryptomeria japonica) pollen. Isolation and characterization of the mountain cedar ( Juniperus ashei) pollen major allergen, Jun a 1.
Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease 31 the results were generated cheap fildena 50mg online, and whether the laboratory work was performed under protocols that permit results feedback order 100 mg fildena visa. These limiting factors mean that most research results are not integrated into clinical care buy generic fildena 25mg on-line. Expert opinion on the duty to inform research participants of clinically relevant results vary widely fildena 50 mg fast delivery. Indeed, many researchers are reluctant to contribute data to a common resource as it may expose them to questions about whether feedback to participants is necessary or desirable. In a sense, this challenge has parallels with the building of Europe s great cathedrals studies started by one generation will be completed by another, and plans will change over time as new techniques are developed and knowledge evolves. Many patients are already put on powerful drugs in their 40 s, 50 s, and 60 s that they will take for the rest of their lives. The very success of some cancer treatments is shifting attention from short-term survival to the long-term sequelae of treatment. For all these reasons, the era during which a genetic researcher simply needed a blood sample and a reliable diagnosis is passing. Outcomes research is also creating new opportunities for a close integration of medicine and data-intensive biology. Cost constraints on health-care services as well as an increasing appreciation of how often conventional medical wisdom is wrong has led to a growing outcomes-research enterprise that barely existed a few decades ago. The requirements of outcomes researchers for access to uniform medical records of large patient populations are remarkably similar to those of molecularly oriented researchers. Multiple Stakeholders Are Ready for Change The tremendous recent progress in genetics, molecular biology, and information technology has been projected to lead to novel therapeutics and improved health-care outcomes with reduced overall health-care costs. Clinical and basic researchers have learned that for their collective efforts to provide affordable improvements in health care, increased collaboration and coordination are required. Public-private collaborations are needed to combine longitudinal health outcomes data with new advances in technology and basic research. Such initiatives are essential to gain and apply the specific biological knowledge required to develop new approaches to treat and prevent disease. A dynamically evolving Knowledge Network of Disease would provide a framework in which a closer, more effective, relationship between clinical and basic researchers could thrive. Nowhere is the need for change more evident and urgent than in the pharmaceutical and biotechnology industries. Despite a massive increase in the amount of genomic and molecular information available over the past decade, the number of effective new therapies developed each year has remained stable, while the cost of developing each successful therapy has increased dramatically (Munos 2009). Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease 32 large number of novel drug targets, an inadequate biological understanding of these targets has resulted in an ever-increasing failure rate of expensive clinical trials (Arrowsmith 2011a,b). The pharmaceutical and biotechnology industries are now leading proponents for developing public-private collaborations and consortia in which longitudinal clinical outcomes data can be combined with new molecular technology to develop the deep biological understanding needed to re-define disease based on biological mechanisms. Given the time scale on which private entities must seek return on investment, there is an increased willingness to regard much of this information as pre-competitive. Hence, the information itself, and the costs of acquiring it, must be widely shared. A major beneficiary of the proposed Knowledge Network of disease and New Taxonomy would be what has been termed precision medicine. Today, researchers look for relatively small differences between treated and untreated patients in trials that involve unselected patients, with little insight into the biological heterogeneity among the patients or their diseases. This approach requires a much larger number of patients, more time, and greater costs to assess the effectiveness of new therapies than would more targeted study designs. By using a precision-medicine approach to focus on those patients early in the drug-development process who are most likely to be helped, fewer side effects and reduced costs are likely to ensue. In such studies, compliance will likely be better, treatment duration longer, and therapeutic benefits more obvious than is the case with traditional designs. Greater therapeutic differences could also result in more efficient regulatory approval, and faster adoption by physicians and payers. Access to this knowledge allowed the pharmaceutical industry scientists to modify their clinical trial to look specifically at a cohort of patients with this translocation, and the results were dramatic. For those patients who had the translocation, the median disease-free survival with Crizotinib was a year, compared to just a few months with the standard of care. Thus, even in a trial that involved only a small number of patients that were compared to historical controls, it was obvious that the drug was active. In contrast, in an unselected patient population, most patients did not benefit from this drug and it was unclear whether the drug had any activity. Data sharing needs to occur across companies and across academic institutions to ensure that everyone benefits from fundamental biological knowledge. Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease 33 government, and perhaps most importantly the public at large, will be required to support and sustain the changes required for development of innovative new therapies that improve health outcomes based on the proposed Knowledge Network of Disease and associated New Taxonomy. Public Attitudes Toward Information and Privacy Are in Flux Genetic privacy was a central preoccupation during the early years of genomics, which led to implementation of stringent regulatory procedures to limit the use of genetic data in patient oriented research (Andrews and Jaeger 1991). During the ensuing years, the diffusion of the internet into every corner of our lives is driving massive changes in public attitudes toward privacy. Research studies of public attitudes reveal deep ambivalence about informational privacy. In the particular arena of genetic information and health records, members of focus groups typically grasp the broad social benefits of sharing data. A consistent theme is that people who contribute their own information to public databases want to be asked for permission, to have a clear explanation of how the data will be used, and to be treated as true partners in the research process (Damschroder et al. Although privacy concerns remain, there is little evidence that the public has the extreme sensitivity toward genetic data that many researchers anticipated 25 years ago. The development of the proposed Knowledge Network of Disease and its associated New Taxonomy could take advantage of these forces to inspire revolutionary change. This Committee regards commitment to the development of these resources as a powerful unifying idea that could harness and, to an appropriate degree, redirect the creative energies of the key constituencies to achieve the full potential of biology to improve health outcomes. Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease 3 What Would a Knowledge Network and New Taxonomy Look Like? In the previous chapter, the Committee outlined the reasons it concluded that the time is right to develop a Knowledge Network of Disease and New Taxonomy. But what would these resources look like and what implications would they have for disease classification, basic research, clinical care and the health-care system? This chapter describes the Committee s vision of a comprehensive Knowledge Network of Disease and New Taxonomy that would unite the biomedical-research, public-health, and health-care-delivery communities around the related goals of advancing our understanding of disease pathogenesis and improving health. The Committee envisions that the proposed resources would have several key features: x They would drive development of a disease taxonomy that describes and defines diseases based on their intrinsic biology in addition to traditional physical signs and symptoms. The Knowledge Network of Disease Would Incorporate Multiple Parameters and Enable a Taxonomy Heavily Rooted in the Intrinsic Biology of Disease Physical signs and symptoms are the overt manifestations of disease observed by physicians and patients. Physical signs and symptoms are generally also difficult to measure quantitatively. Indeed, in a strict sense, all diseases are presumably asymptomatic for some latent period following the initiation of pathological processes. As a consequence, diagnosis based on traditional signs and symptoms alone carries the risk of missing opportunities for prevention, or early intervention can readily misdiagnose patients altogether. Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease 36 diseases become clinically evident, obtaining optimal diagnostic results can depend on supplementing standard histology with ancillary genetic or immunohistochemical testing to identify specific mutations or marker proteins. Biology-based indicators of disease such as genetic mutations, marker-protein molecules, and other metabolites have the potential to be precise descriptors of disease. They can be measured accurately and precisely be it in the form of a standardized biochemical assay or a genetic sequence thus enabling comparison across datasets obtained from independent studies. Numerous molecularly-based disease markers are already available, and the number will grow rapidly in the future. Eventually, it is likely that extensive molecular characterization of individuals will occur routinely as a normal part of health care even prior to appearance of disease thereby allowing the collection of data on both sick and healthy individuals on a scale vastly exceeding current practice. In addition to providing a new resource for research on disease processes, these data would provide a far more flexible and useful definition of the normal state, in all its diversity, than now exists. The ability to make such measurements on both non-affected tissues and in sites altered by disease would allow monitoring of the development and natural history of many disorders about which even the most basic information is presently unavailable. Gene- environment interactions have been implicated in a diverse group of diseases and pathological processes, including some psychological illnesses (Caspi et al. Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease 37 2009), and cardiovascular reactivity (Williams et al. Therefore, data added to the Information Commons should not be limited to molecular parameters as they are currently understood: patient-related data on environmental, behavioral, and socioeconomic factors will need to be considered as well in a 7 thorough description of disease features (see Box 3-1: The Exposome). Despite the focus on the individual patient in the creation of the Information Commons, the Committee expects that the inclusion of patients from diverse populations coupled with the incorporation of various types of information contained in the exposome will result in a Knowledge Network that could also inform the identification of population level interventions and the improvement of population health. For example, a better understanding of the impact of a sedentary lifestyle at the molecular level could conceivably facilitate the development of new approaches to physical education in early childhood. In addition, findings from the Knowledge Network and the New Taxonomy could reveal yet unidentified behavioral, social, and environmental factors that are associated with particular diseases or sub-classifications of diseases in certain populations and are amenable to public health interventions. A long-range goal is to ascertain the combined effects of these exposures by assessing the biomarkers and diseases they influence. In its broadest definition, the exposome encompasses all exposures internal (such as the microbiome, described elsewhere in this report) and external across the lifespan. Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease 38 Zanobetti et al. By incorporating data derived from multi-level assessments, a Knowledge Network of Disease could lead to better understanding of the variables and mechanisms underlying disease and health disparities, thereby helping to reveal a truer picture of the ecology of human health and facilitating a more holistic approach to health promotion and disease prevention. Asthma illustrates the interplay of social, behavioral, environmental, and genetic factors in disease classification. It is estimated that various types of asthma affect more than 300 million people worldwide. The term asthma is now used to refer to a set of signs and symptoms including reversible airway narrowing ( wheezing ), airway inflammation and remodeling, and airway hyper-reactivity. These various signs and symptoms likely reflect distinct etiologies in different patients. Many subjects with asthma have an allergic component, while in other cases, no clear allergic contributor can be defined (Hill et al. In some patients, asthma attacks are precipitated by exercise or aspirin (Cheong et al. Some patients, particularly those with severe asthma, may be resistant to treatment with corticosteroids (Searing et al. This phenomenological approach to asthma diagnosis has led to a plethora of asthma sub-types such as allergic asthma, exercise-induced asthma, and steroid-resistant asthma that may be clinically useful but provide little insight into underlying etiologies. However, these findings still leave most of the genetic influences of asthma unexplained (Li et al. Since the burden of asthma disproportionately affects children living in socioeconomically disadvantaged neighborhoods (D. A knowledge- network-derived-taxonomy based on the biology of disease may help to divide patients with asthma as well as many other diseases into subtypes in which the different etiologies of the disorder can be better understood, and for which appropriate, subtype-specific approaches to treatment and prevention can be devised and tested. Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease 39 The Proposed Knowledge Network of Disease Would Include Information about Pathogens and Other Microbes Particularly because of advances in genomics, the proposed Knowledge Network of Disease has unprecedented potential to incorporate information about disease-causing and disease-associated microbial agents.