Presentation on theme: "GASTROENTERITIS Dr. Bikha Ram Devrajani Professor Medicine"— Presentation transcript:
1GASTROENTERITIS Dr. Bikha Ram Devrajani Professor Medicine MBBS(SINDH),FCPS(PAK),FACP(USA),FRCP(LONDON)Professor MedicineLiaquat University of Medical & Health SciencesJamshoro
2GastroenteritisGastroenteritis is a nonspecific term for a variety of pathologic states of the gastrointestinal tract.The primary manifestation is diarrhea, but it may be accompanied by nausea, vomiting, and abdominal pain.A universal definition of diarrhea does not exist, although patients seem to have no difficulty defining their own situation.
3GastroenteritisAlthough most definitions center around the frequency, consistency, and water content of stools, the author prefers the definition that diarrheal stools take the shape of their container.
4GastroenteritisSeverity of illness may vary from mild and inconvenient to severe and life threatening.Appropriate management requires extensive history and assessment and appropriate general supportive and, often, etiology-specific treatment.Diarrhea associated with nausea and vomiting is referred to as gastroenteritis.
6Diarrhea is……..A symptom characterized by an abnormal increase in stool frequency or liquidityAcute diarrhea is usually self limiting and lasts hours, sometimes up to 7 daysChronic diarrhea lasts more than 4 weeks, should seek medical care
7Global Problem4.6 million children less than 5 years of age die of diarrheal diseases.Diarrhea accounts for 19% of all deaths among children ages 0-4.Eighty-five percent of diarrheal deaths occur in the first year of life.World Health Organization WHO Fact Sheet: Reducing Mortality from Major Childhood Killer Diseases. Fact Sheet Number 180.Centers for Disease Control and Prevention Diarrhea: The Management of Acute Diarrhea in Children: Oral Rehydratioin, Maintenance, and Nutritional Therapy.Graph.
8OUTBREAKSJuly 1998: E coli 0157:H7 infection outbreak from contaminated water supply in Wyoming, more than 60 infectedJuly 1995: 77 cases of cryptosporidiosis at a day camp in Florida, most likely secondary to water hose contaminationAugust-September 1999: E coli 0157:H7 infections secondary to contaminated well water in Washington County Fair (New York)
9OUTBREAKSThree to five billion cases of acute diarrhea occur yearly, and it is the leading cause of death in many underdeveloped countries.Approximately 30-50% of visitors to developing countries will develop, and perhaps return with, diarrhea.
10Age Gastroenteritis may occur at any age. Morbidity and mortality are much higher in the very young and the very old.
11TransmissionDiarrheal agents are mostly spread via the fecal-oral route.physical contact with infected feceseating or drinking contaminated food or waterperson to person relayWorld Health Organization The Epidemiology and Etiology of Diarrhea.
12Socioeconomic factors PovertyOvercrowdingPoor sanitationContamination of waterInadequate food hygieneUNICEF The State of the World’s Children, Oxford and New York: Oxford University Press.
13Risk Factors Household crowding Low maternal education Low birth weightClaeson, M., & Merson, M Global progress in the control of diarrheal diseases. Pediatric Infectious Diseases Journal, 9:
14Behavioral FactorsFailure to breast-feed exclusively for the first 4-6 months of lifeFailure to continue breast-feeding until one year of ageUsing infant bottlesStoring food at room temperatureContaminated drinking waterFailure to wash handsFailure to dispose of feces hygienicallyClaeson, M., & Merson, M Global progress in the control of diarrheal diseases. Pediatric Infectious Diseases Journal, 9:
16Prevention Strategies Breast FeedingImproved weaning practicesProper use of waterHand washingDisposing feces properlyEffectiveness of measles vaccination
17DiarrheaThe passing of 3 or more watery or loose stools in a 24-hour period.Three types: acute waterypersistentdysenteryWorld Health Organization The Epidemiology and Etiology of Diarrhea.World Health Organization WHO Fact Sheet: Reducing Mortality from Major Childhood Killer Diseases. Fact Sheet Number 180.
18Diarrheal illnesses also may be classified Osmotic, due to an increase in the osmotic load presented to the intestinal lumen, either through excessive intake or diminished absorptionInflammatory (or mucosal), when the mucosal lining of the intestine is inflamed.Secretory, when increased secretory activity occursMotile, caused by intestinal motility disorders
19Etiological Agents Bacterial, Viral, and Parasitic Agents Protozoans RotavirusEnterotoxigenic E. ColiShigellaeSalmonellaeVibrio CholeraeCampylobacter jejuniCryptosporidiumProtozoansGiardiaEntamoebaRotavirusGiardiaE.ColiWorld Health Organization
20Etiology of diarrheaDiarrhea is a symptom of an underlying pathology or infectionViral gastroenteritisBacterial gastroenteritisProtozoal diarrheaAntibiotic associated diarrheaAIDS associated diarrheaFood-induced diarrhea
21Etiology of diarrhea Viral (50-70%) The Norwalk virus is the leading cause of viral gastroenteritis in the United States. Norwalk virus belongs to the species of Noroviruses (formerly known as Norwalk-like viruses). Noroviruses, along with the Sapoviruses (formerly known as Sapporo-like viruses) are members of the Caliciviridae family of viruses.Caliciviruses: Various caliciviruses, other than Norwalk, are likely responsible for many out breaks of previously unidentified viral gastroenteritis.Rotavirus: A leading cause of gastroenteritis in children, but can also be found in adults. May cause severe dehydration.AdenovirusParvovirusAstrovirusCoronavirusPestivirusTorovirus
23Etiology of diarrhea Parasitic (10-15%) Food-borne toxigenic diarrhea GiardiaAmebiasisCryptosporidiumCyclosporaFood-borne toxigenic diarrheaPreformed toxin - S aureus, B cereusPostcolonization - V cholera, C perfringens, enterotoxigenic E coli, Aeromonas
24Etiology of diarrheaShellfish poisoning and poisoning from other marine animalsParalytic shellfish poisoning (PSP) - SaxitoxinNeurologic shellfish poisoning (NSP) - BrevotoxinDiarrheal shellfish poisoning (DSP) - Okadaic acidAmnesic shellfish poisoning - Domoic acidCiguatera (ciguatoxins)Scombroid (conversion of histidine to histamine)
25Etiology of diarrhea Drug-associated diarrhea Pseudomembranous colitis Antibiotics due to alteration of normal floraLaxatives, including magnesium-containing antacidsColchicineQuinidineCholinergicsSorbitolPseudomembranous colitisOvergrowth of C difficilePositive C difficile assay
26Etiology of diarrhea Other causes Unknown agents, especially in developing countriesIschemic colitisUlcerative colitisCrohn diseaseCarcinoid tumor or vasoactive intestinal peptide tumor (VIPoma)AIDSDumping or short bowel syndromeRadiation or chemotherapy
27Viral gastroenteritis 80-85% of episodes of acute diarrhea are caused by virusesVirus transmitted by contaminated food or waterClinical features include 12-48hr incubation period followed by vomiting, watery diarrhea and low grade feverIllness lasts 5-8 days, treatment is fluid and electrolyte therapy
28Bacterial gastroenteritis Common pathogens are Campylobacter, Salmonella, Shigella, E.coli, Staphylococcus, ClostridiumIf attack is in small intestine patients usually experience abrupt onset of large volume, watery stools, upper abdominal pain, nausea, vomiting, cramps, and low grade feverIf attack is in large intestine, patients may experience dysentery like syndrome including bloody or mucousy diarrhea
29Traveler’s diarrhea A form of bacterial gastroenteritis Usually occurs when people travel to warmer climates with poor sanitationMost commonly caused by E.coliCharacterized by sudden onset of loose stools, nausea, occasional vomiting, cramps, bloating, malaise and low grade feverUsually subsides over 3-4 days
30Protozoal diarrheaGiardia lamblia and entamoeba histolytica are protozoa associated with diarrheaUsually acquired traveling to mountainous or recreational water areas, drinking stream or pond waterNo nonprescription therapy for protozoal diarrhea, metronidazole is treatment of choice
31Antibiotic associated diarrhea Frequency of diarrhea is largely dependent on the extent to which the drug disrupts the normal intestinal floraAbx that have broad spectrum activity against aerobes and anaerobes can produce diarrheaAAD may be caused by an overgrowth of abx resistant bacteria, fungi, or toxin producing C.difficileDiarrhea caused by C.difficile is usually watery and greenish-mucoidThere are no nonprescription treatments for eradicating C.difficile
32AIDS Associated Diarrhea Patients with AIDS or HIV are known to be susceptible to intestinal infections that produce diarrheaThese patients should not self-manage their diarrhea, they should see their physician
33Food-Induced Diarrhea Food intolerance can provoke diarrheaThe enzyme lactase hydrolyzes disaccharides into monosaccharidesWhen you lack the lactase enzyme, disaccharides can not be hydolyzed to monosaccharidesDisaccharides pool in lumen causing an osmotic imbalance which draws fluid into the lumen and causes diarrhea
38Signs of DehydrationCommon: dizziness, thirst, confusion, lethargy, fatigueSerious: low BP, fever, vomiting, abdominal cramps, nausea, muscle aches, mucously stools, weight-lossMild dehydration: 3-5% weight-lossSevere dehydration: 10% weight-loss (can be very serious in infants, may lead to cardiovascular collapse and renal failureMild/moderate diarrhea are self-treatableSevere diarrhea: non self-treatable
39Laboratory Investigations Stool DR, ova & cyst, and C/S.CBC.Serum electrolytes.Blood urea.Other investigations depend upon the causative agent.
40Treatment Options Treatment Outcomes Assess and Correct electrolyte and fluid loss2. Manage diet or disease3. Provide relief4. Identify cause
42Fluid and Electrolyte Replacement Not more than mEq/L of Na for rehydrationNot more than mEq of Na for maintenanceCarb to Na ratio should be 2:1Important in children and infantsAll patients should rehydrate and maintain during diarrheal episode
43Loperamide Good for treatment of traveler’s diarrhea and IBD Works by slowing intestinal motilityUse 4mg initially, then 2mg after each loose stool but do not exceed 16mg/day (8 tablets)Do not use in children <6 years old use electrolyte tx instead
44Adverse Reactions Can cause occasional dizziness and constipation May worsen effects of invasive or inflammatory bacterial infection should not use for food borne illnessMay cause toxic megacolon in ABX induced diarrhea DO NOT use for ABX associated diarrhea - refer to physicianIn children less than 6 years old
45Absorbents Include attapulgite, kaolin, pectin Do not recommend because of decreased absorption of other drugs
46Polycarbophil Used for non-specific diarrhea Bulk laxative that is also effective in treating diarrhea (can also treat constipation)Can absorb up to 60X weight in waterUse 2 (500mg) tablets 4 times daily or after each loose stool (up to 6g a day)
47Adverse Reactions Metabolically inert No systemic toxicity has been shownSide effects include dose-related epigastric pain and bloatingMay decrease absorption of warfarin, digoxin, tetracycline, and ciprofloxacin
48Bismuth Subsalicylate BSS Used for non-specific diarrhea, indigestion, tx and prevention of traveler’s diarrhea, as adjuvant to ABX for treating H.pylori peptic ulcer diseaseReported to have an antisecretory mechanism to bind bacterial toxins, and to have anti-inflammatory and antibacterial propertiesTake 2 (262mg) tablets every hour up to 16 tablets a dayNot recommended for children <2 years old
49Adverse ReactionsMay reach toxic levels of salicylate if patients are taking aspirin or other salicylate containing drugsPatients sensitive to salicylates should not useBlackened stool and tongue may occur - harmless
50Enzymes - lactase For lactose intolerance Take 1-3 tablets with first bite of dairy productJust avoid dairy products
51Things to Remember Always remember to rehydrate Special populations (elderly, <3 years old, pregnant) require medical referralHealthy patients usually improve within 24 to 48 hoursIf condition remains or worsens after 48 hours - refer to MD
53ControversiesUnderuse of ORT and overuse of drugs“Boil the water”
54Complications of Diarrhea Acute diarrhea may cause severe dehydration and electrolyte imbalanceInfants, young children, and the elderly are most at risk for dehydrationChildren less than 2 yrs of age often have complications that require hospitalization
63First steps for managing an outbreak of acute diarrhoea THIS PRESENTATION AIMS AT GUIDING YOU THROUGH THE VERY FIRST DAYS OF AN OUTBREAK
64WORLD HEALTH ORGANIZATION Is this the beginning of an outbreak?
65WORLD HEALTH ORGANIZATION You might be facing an outbreak very soon ifYou have seen an unusual number of acute diarrhoeal cases this week and the patients have the following points in common:they have similar clinical symptoms (watery or bloody diarrhoea)they are living in the same area or locationthey have eaten the same food (at a burial ceremony for example)they are sharing the same water sourcethere is an outbreak in the neighbouring community
66WORLD HEALTH ORGANIZATION You have seen an adult suffering from acute watery diarrhoea with severe dehydration and vomitingIf you have some statistical information from previous years or weeks verify if the actual increase of cases is unusual over the same period of time.
67WHAT DO I HAVE TO DO WHEN I SUSPECT AN OUTBREAK? 1. Inform and ask for help2. Protect the community3. Treat the patients
83Mortality/MorbidityEstimates for mortality and morbidity vary widely. In the United States, 210,000 pediatric hospitalizations occur yearly with as many as 10,000 deaths.Internationally, mortality rate is 5-10 million deaths each year.