Diarrhea Dr.K.S.Sunil MBBS, MD, PGDGM

Increase in frequency, size or loosening of bowel movements. Differentiate from fecal incontinence or functional bowel disease- normal stool weight With western diet- less than 200g/day

Pathophysiology Increased active anion secretion Decreased absorption of water and electrolytes

Types Transmissible agents Noninfectious - abnormal mucosa –Inflammatory Bowel disease –Celiac disease, microscopic colitis, eosinophilic and allergic gastroenteritis, radiation enteritis Noninfectious - normal mucosa –Osmotic diarrhea –Mal-absorption –Rapid intestinal transit- IBS

Infectious diarrhea Mostly feco-oral route Bacterial Viral Parasitic

Bacterial Watery –Enterotoxigenic- Vibrio cholera Enterotoxigenic E.coli –Food borne toxins- Bacillus cereus Clostridium perfringens –Mycobacterium avium-intracellular complex

Bacterial Bloody –Invasive Campylobacter jejuni –Destructive Shigella Enteropathogenic E.coli Clostridium difficile

Viral Rotavirus –Children less than 2 years –Most common cause of diarrhea in children all over the world Norwalk –Older children and adults These viruses injure the small intestinal mucosa Watery diarrhea CMV –Immunocompromised

Parasitic Protozoa –Giardia lamblia –Entamoeba histolytica –Cryptosporidium Helminths –Ascaris lumbricoides –Ancylostoma –Strongyloides stercoralis –Trichinella spiralis –Capillaria philippensis

Opportunistic pathogens Clostridium difficile –Nosocomial pathogens in healthcare and long term care facility –Poor handwashing –Clindamycin, cephalosporins, ampicillin –Exotoxin mediated

In immunocomromised Hosts Besides the common pathogens, –Giardia –Legionella –Candida albicans –Cryptosporidium species –Mycobacterium avium-intralcellulare –CMV

Others Tropical sprue –In those who live or travel to the tropics –Overgrowth of predominantly coliform bacteria in the small intestine Whipple’s Disease –Infection by Tropheryma whippelii –HLA B27

History Is it truly diarrhea? Duration- –acute <3 weeks –Chronic >4 weeks Texture Frequency Blood?

History Fever Vomiting Abdominal pain Fainting or dizzyness Travel Drug use Diet Weight loss

History Alcohol Abdominal operations Chemotherapy Radiation Immune status Comorbidities

Physical Vital signs –Orthostatic signs –Hyperventilation- acidosis Volume status –Skin tenting –Dry mucous membranes –Resting tachycardia –Hypotension –Sunken eyeballs –Scaphoid abdomen

Physical Abdominal and rectal exam. –Distension –Bowel sounds –Tenderness –Masses Stool swab- culture

Physical Chronic diarrhea –Malnutrition Weight loss Muscle wasting Tetany Oral and skin lesions Peripheral neuropathy Ataxia Edema

Labs Stool tests for inflammation –Pus cells- specific but low sensitivity( about 50%) –Lactoferrin Released from leucocytes during an inflammatory reaction Sensitivity is 90% but less specific

Labs Stool culture –Positive in only 40 to 60% Stool for ova and parasites Stool for Clostridium difficile toxin Stool Sudan test for fat Stool Electrolytes-differentiates secretory diarrhea from osmotic diarrhea Stool pH-<7 indicates carbohydrate malabsorption

Other investigations Flexible sigmoidoscopy –Pseudomembranes –Inflammation –Melanosis coli Blood Hormone levels –Serum gastrin, VIP, somatostatin, cortisol, neurokinins, calcitonin –Carcinoid- serotonin, urine 5-hydroxyindoleacetic acid

Management Fluid therapy Persons with moderate to severe diarrhea lose large amounts of Na, CL, K, HCO3 & H20 Pre renal azotemia, hypokalemia, metabolic acidosis –ORS –IV Fluids

ORS-principle Saline solution (water plus Na+) by mouth - no beneficial effect –Na+ absorption is impaired in the diarrhoeal state –if the Na+ is not absorbed water cannot be absorbed. –Excess Na+ in the lumen of the intestine causes increased secretion of water and the diarrhoea worsens.

ORS Glucose - absorbed through the intestinal wall - unaffected by the diarrhoeal disease state - sodium is carried in conjunction through by a co-transport coupling mechanism. This occurs in a 1:1 ratio, one molecule of glucose co-transporting one sodium ion (Na+).

Starch – –metabolized in the intestine to glucose and therefore it has the same properties of enhancing sodium absorption –less osmotic effect in the lumen of the intestine.

Citrate, a base precursor, corrects acidosis and enhances the absorption of water and electrolytes

ORS-History First developed in the early 1950’s and was formulated to mirror ions lost in stool. In the early 1960’s the mechanism by which ORT works, the coupled transport of sodium and glucose, was discovered. 6 In 1971, the efficacy of ORT demonstrated during an epidemic of cholera in a refugee camp in Bangladesh. –ORT reduced the death rate from more than 50% to only 5%. 7 By the early 1970’s a consensus was reached about the effectiveness of ORT.

ORS Lancet- "potentially the most important medical advance this century" World Health Organization estimates that 90% of diarrheal deaths worldwide could be prevented with appropriate treatment with ORS

ORS Start early Rice based ones ( Glucose polymers) increase intestinal fluid absorption In adults – use urine output for monitoring

ORS Sodium Chloride 3.5 grams Sodium Bicarbonate 2.5 grams Potassium Chloride 1.5 grams Glucose 20 grams

ORS SolutionNa Mmols /L KClCarb.Osmolality WHO Rice Based

ORS- caution A number of studies have addressed the concern that ORT can lead to hypernatremia in neonates and infants. These studies show that administration of breast milk or plain water after rehydration prevents this problem. 1

IV Fluids Must contain Potassium and a base –Ringer’s lactate

Chronic Diarrheas Zn and Magnesium replacement

Antibiotics Invasive bacterial Enteritis- esp.Shigellae –Quinilone orally twice daily for 3 days Cholera Traveler's diarrhea –Prophylactic- not recommended –A single dose of oral Quinilone at onset Clostridium difficile –Metronidazole –Oral Vancomycin

Antimotility agents Should be avoided Concern for promoting bacterial invasion or prolonging the infection

Food Do not withhold –Withholding food, even for one or two days, greatly exacerbates the malnutrition –Coupled with anorexia, caused partly by chronic potassium depletion, causes a vicious circle –It is this diarrhoea/malnutrition cycle rather than acute dehydration that causes almost half of the five million deaths a year in under five year old children that are associated with diarrhoeal disease.

Good nutrition and hygiene can prevent most diarrhea. Thank You!