ACUTE AND CHRONIC DIARRHOEA Year 4 Internal Medicine Notes

ACUTE AND CHRONIC DIARRHOEA Year 4 · Internal Medicine Collection: 4TH YEAR ALL NOTES / IMED / IMED 4.1 / ALEX -- Slide 1 ACUTE AND CHRONIC DIARRHOEA Dr Alex Mogere Consultant Physician Slide 2 OUTLINE Introduction. Definitions. Classification of Diarrhoea. Approach to a patient with diarrhea. Acute Diarrhea. Chronic Diarrhea. Slide 3 Introduction Diarrhea is a major health concern in developing countries. 4 billion global cases of diarrhea per year. It is one of the most common clinical signs of gastrointestinal disease, but also can reflect primary disorders outside of the digestive system Mainly affects <2 yr olds Slide 4 Ct. introduction About 80% of all hospital attendances in Kenya can be attributed to preventable diseases\nat least 50% of these preventable diseases are linked to poor sanitation, BMC Public Health volume 20 Slide 5 Definitions Diarrhea is best described as too frequent passage of too loose (unformed) stools. It is frequently accompanied by urgency, and occasionally incontinence.\nWhen considering a patient with diarrhea the following must be considered:\nfrequency ( 3 movements/day),\nconsistency (loose/watery),\nvolume ( 200 g/day) and\nwhether the condition is continuous. Slide 6 Definitions Acute: Diarrhea lasting less than 2 weeks, Persistent: 2 to 4 weeks, and\nChronic –diarrhea lasting more than 4 weeks. Dysentery: diarrhea with visible blood in the stool. Pseudodiarrhea - frequent passage of small volumes of stool. Often associated with rectal urgency and accompanies the irritable bowel syndrome or anorectal disorders e.g. proctitis.\nFecal incontinence - involuntary discharge of rectal contents, most often caused by neuromuscular disorders or structural anorectal problems Slide 7 Classification: 3. Inflammatory diarrhea: results from direct damage to the small or large intestinal mucosa. This interferes with the absorption of sodium salts and water and is complicated by exudation of serum proteins, blood and pus. Infectious or inflammatory disorders of the gut cause this kind of diarrhea. 4. Dysmotility diarrhea: Disorders in motility that accelerate transit time could decrease absorption, resulting in diarrhea even if the absorptive process per se was proceeding properly.\nNB: In most instances of diarrhea two or more of these four mechanisms are at work. Slide 9 Causes of Diarrhea Infective causes\nBacterial, e.g. Campylobacter jejuni Salmonella sp. Shigella, Clostridium botulinum GI TB Viral, e.g. rotavirus\nFungal, e.g. histoplasmosis\nParasitic, e.g. amoebic dysentery (Entamoeba histolytica) schistosomiasis Giardia intestinalis\nEndocrine\nZE syndrome\nVipoma\nCarcinoid syndrome\nThyrotoxicosis\nMedullary carcinoma of thyroid\nDiabetic autonomic neuropathy Non-infective causes of diarrhoea\nInflammatory bowel disease\nPseudomembranous colitis\nRadiation proctitis or colitis\nBehçet's disease Diverticular disease\nIschaemic colitis\nMalabsorption\nDrugs - many, including laxatives, metformin anti cancer drugs,NSAIDS\nIrritable bowel syndrome and functional diarrhoea\nToxins(mushroom,amanita etc) Factitious diarrhoea Purgative abuse\nDilutional diarrhoea Slide 12 Infectious diarrhea &systemic manifestations Reiters syndrome-arthritis, urethritis and conjunctivitis, may come following c.jejuni, salmonella,Yersinia,& shigella HUS(Haemolytic uremic syndrome from EHEC(0157:H7) & shigella Slide 13 Approach to a patient with Diarrhea. History: Is it truly diarrhea? Duration? The stool: consistency?, frequency?, volume? any visible blood?. Any systemic symptoms:Fever, tachycardia, weight loss? Underlying Risk factors: Age, immune status, recent travel, medications, known food allergy? Presence and location of abdominal pain? Slide 14 Approach to Diarrhea Physical examination: Always look for signs of dehydration and malnutrition. Vital signs: tachycardia, hypotension, tachypnea. Skins turgor and tonus. Systemic features of any underlying disease e.g. stigmata of HIV. Abdominal exam: distension, bowel sounds, tenderness, masses and rectal examination Slide 15 Approach to diarrhea patient. Laboratory and diagnostic studies: chosen on the history, acute vs. chronic diarrhea. Stool analysis: Microscopy: for features of intestinal inflammation. Ova and Cyst. Toxins like C.deficile Culture. Quantitative and qualitative fat analysis. FHG, LFTs and U/E/CR Imaging as per the clinical presentation of the patient. Slide 16 Acute Diarrhea More than 90% of cases of acute diarrhea are caused by infectious agents; these cases are often accompanied by vomiting, fever, and abdominal pain.\nThe remaining 10% or so are caused by medications, toxic ingestions, ischemia, and other conditions. In immunocompetent patients it is usually self limiting and intervention may be limited to oral rehydration if there are no signs of significant fluid loss. Slide 17 Acute diarrhea: Presence or absence of blood in stool Acute diarrhea with blood Bacillary dysentery (shigellosis) Enterohemorrhagic EC Campylobacter