ACUTE AND CHRONIC DIARRHEA

KHOI TRAN, M.D.

ASSOCIATE PROFESSOR

GASTROENTEROLOGY DIVISION

DEPARTMENT OF MEDICINE

UC IRVINE SCHOOL OF MEDICINE

ACUTE DIARRHEA IN ADULT

DURATION < 14 DAYS VIRAL GASTROENTERITIS: MOST COMMON

ADULT—NOROVIRUS (20M) CHILDREN—ROTAVIRUS

BACTERIAL GASTROENTERITIS: RELATED TO TRAVEL, CO-MORBIDITIES, FOODBORNE.

MOST ARE SELF LIMITED, DO NOT REQUIRE STOOL STUDIES. TREATMENT IS FOCUSED ON PREVENTION AND DEHYDRATION.

HISTORY IS KEY TO DX

DIARRHEA DURATION, FREQUENCY, CHARACTER. VOMITING MORE SUGGESTIVE OF VIRUS OR PREFORMED

BACTERIAL TOXIN. NOROVIRUS:

CRUISE SHIP, SCHOOL, RESTAURANTS TRANSMISSION THROUGH ILL CONTACT INCUBATION 12-48 HRS, DURATION 1-3 DAYS

INVASIVE BACTERIA: FEVER, PAIN, TENESMUS, BLOODY STOOL.

NON-INFLAMMATORY VS INFLAMMATORY DIARRHEA

NON-INFLAMMATORY USUALLY VIRAL OR TOXINS PROMOTE INTESTINAL

SECRETION LARGE VOLUME, NONBLOODY NO FECAL LEUKOCYTES E. COLI, STAPH, GIARDIA,

VIBRIO, BACILLUS CEREUS, C.

PERFRINGENS,

INFLAMMATORY INVASIVE BACTERIA DISRUPT MUCOSA. FEVER, PAIN, LOW VOL, BLOODY. FECAL LEUKOCYTES. SALMONELLA, CAMPYLOBACTER, SHIGELLA, E. COLI, C. DIFF.

CLUES TO DX OF ACUTE DIARRHEA

HISTORYPAIN, BLOODY STOOL, AFEB.BUFFET FRIED RICE SYNDROMEMOUNTAINS, COUNTRYSIDEASIA, INDIA RECENT TRAVELFOOD HANDLED WITHOUT ADDITIONAL COOKINGRAW CHICKEN CONTAM.FOOD SERVICE GERM(PRE-COOKED KEPT <140F)

SOURCERAW MILK, RAW BEEF, FRIED RICE AND SOILUNTREATED WATER, CAMPINGRAW SEAFOODSALADS, CREAMY PASTRY, SANDWICHUNDERCOOKED BEEF, PORK, CHICKENCAFETERIA, CATERED MEAT

PATHOGENTOXIGENIC E. COLI (265K)BACILLUS CEREUS (<100K)GIARDIA (15K)VIBRIO (8K)STAPH AUREUS (240K)SALMONELLA (1.1M), CAMPYLOBACTER (1M)SHIGELLA (500K)CLOSTRIDIUM PERFRINGENS (1M)

WHEN TO ORDER STOOL STUDIES

GROSSLY BLOODY STOOL (>30%) SEVERE DEHYDRATION SX MORE THAN FEW DAYS IMMUNOSUPPRESSION NOSOCOMIAL INFECTION C. DIFF FOR UNEXPLAINED DIARRHEA 3 DAYS POST-HOSP (15-20%). O&P NOT NECESSARY, LOW YIELD IN DEVELOPED NATION GIARDIA IF SX >10-14 DAYS.** AVOID INDISCRIMINATE USE OF STOOL STUDIES.

C. DIFF STOOL TESTING

UNEXPLAINED DIARRHEA 3 DAYS POST-HOSP. 7-10X RISK DURING AND WITHIN 1 MO POST ABX RX. 3X RISK WITHIN 2-3 MOS POST ABX RX. IMMUNOSUPPRESSION. ASYMP CARRIERS IN 3% HEALTHY ADULTS, 40% HOSPITALIZED

PTS. INCREASED RISK WITH PPI USE AND IBD FLARE. STOOL FOR NAAT GENES BY PCR BETTER THAN TOXINS.

FEEDING RESTRICTIONS?

EARLY REFEEDING REDUCES MUCOSAL PERMEABILITY, ILLNESS DURATION.

BRAT DIET NO LONGER RECOMMENDED. AVOIDING SOLID FOOD FOR 24 HRS NOT NECESSARY.

ANTIBIOTICS?

NOT NECESSARY FOR MOST NON-SEVERE DIARRHEA. MOST OFTEN LIMITED AND CAUSED BY VIRUSES. AFFECT NORMAL FLORA. PROLONG ILLNESS DUE TO C. DIFF SUPERINFECTION. INCREASED RISK OF HUS (17X) PROMOTE RELEASE OF BACTERIAL TOXINS

CHRONIC DIARRHEA

FUNCTIONAL—IBS SECRETORY—MICROSCOPIC, BILE ACID, POSTOP DUMPING INFLAMMATORY—IBD PARASITE—GIARDIA MALABSORPTION—PANCREATIC INSUFF, CELIAC, SIBO. MEDICATIONS—OSMOTIC/SECRETORY.**HISTORY ACCURACY IS CRITICAL.**MOST PRACTICAL TO CHARACTERIZE TYPE BEFORE TESTING AND TREATING.

KEY ELEMENTS IN THE HISTORY:

DURATION > 30 DAYS AGE ONSET/FREQUENCY/VOLUME RELATION TO PO PRESENCE OF PAIN/BLOOD/WEIGHT LOSS/NOCTURNAL SX MEDS CHANGE TRAVEL

**HISTORY TO CHARACTERIZE DIARRHEA TYPE THEN FOCUSED TESTING

FUNCTIONAL—IBS

MOST COMMON CAUSE OF CHRONIC DIARRHEA HALLMARK: NONBLOODY, POSTPRANDIAL, NO WEIGHT LOSS, NL

LABS. LOW VOL (<350ML) DX BY EXCLUSION IN OLDER PATIENT POSTINFECTIOUS CAN RESOLVE WITHIN MONTHS SCREEN FOR CELIAC (4X MORE LIKELY TO HAVE CELIAC THAN

GENERAL POPULATION)

ROME III CRITERIA FOR IBS

ABD PAIN AND BOWEL CHANGE FOR > 6MOS. SX’S > 3 DAYS/WEEK FOR > 3 MOS. 2 OR MORE OF FOLLOWING:

PAIN RELIEVED BY BM. ONSET OF PAIN RELATED TO CHANGE IN STOOL FREQUENCY. ONSET OF PAIN RELATED TO CHANGE IN STOOL APPEARANCE.

**STUDIES CONFIRMED ACCURACY AT 65-100%.

IRRITABLE BOWEL SYNDROME

PREVALENCE: 10-15% ENTIRE US POPULATION ONLY 1 IN 4 SEEK MEDICAL CARE SECOND MOST COMMON REASON FOR MISSING WORK WOMEN TO MEN IS 2:1 RATIO NOT ASSOCIATED WITH ANY SERIOUS MEDICAL CONSEQUENCES NOT RISK FACTOR FOR IBD OR COLON CANCER NOT PUT EXTRA STRESS ON OTHER ORGANS (HEART, LIVER,

KIDNEYS) OVERALL PROGNOSIS IS EXCELLENT

SECRETORY DIARRHEA

LARGE VOL (>1L/DAY), NOCTURNAL SX, UNRELATED TO PO.

FECAL OSMOTIC GAP<50 mOsm/kg. GAP= 290-2(STOOL NA+K)

BACTERIAL TOXINS, BILE ACID, THYROID, MEDS, MICROSCOPIC, POSTOP CCY/GASTRECTOMY/VAGOTOMY/BOWEL RESECTION.

SECRETORY—MICROSCOPIC COLITIS

INTERMITTENT, NOCTURNAL, OLDER AGE. COMMON: 10% OF CHRONIC DIARRHEA CASES. NO SYSTEMIC SX’S, NO BLOOD/WBC IN STOOL. REQUIRE COLONOSCOPY DX: BX TRANSVERSE COLON. UNKNOWN CAUSE, 2 SUB-TYPES:

LYMPHOCYTIC (INFILTRATE LAMINA PROPRIA) COLLAGENOUS (SUBEPITHELIAL COLLAGEN >10MM THICK)

EASY TO TREAT: ENTOCORT PULSE RX

OSMOTIC—LACTOSE, MEDS

LACTOSE INTOL, MG/PHOSPHATE/SULFATE LAXATIVES, SORBITOL.

WATER RETENTION DUE TO POORLY ABSORBED SUBSTANCE. FECAL OSMOTIC GAP>125 mOsm/kg (LOW STOOL NA AND K). STOOL PH<5.5 LACTOSE INTOL.

INFLAMMATORY—IBD

STOOL WBC (IF UNCLEAR IBD VS IBS) FECAL CALPROTECTIN IS USEFUL MARKER TO MONITOR

DISEASE ACTIVITY (ESPECIALLY THOSE WITH OVERLAPPING IBS SX’S). STABLE FOR 7 DAYS.

NOCTURNAL PAIN/BLOOD/WEIGHT LOSS. FE DEFIC ANEMIA, CRP, ESR. PROMETHEUS IBD DX PANEL. COLO +/- MR ENTEROGRAPHY.

PARASITE—GIARDIA

EXCESSIVE GAS, TENESMUS, SECRETORY/MALABSORPTION NO PAIN/BLOOD/WEIGHT LOSS. STOOL DFA (DIRECT FLUORESCENT AB) EMPIRIC RX JUSTIFIED IF DX IS STRONGLY SUSPECTED W

LIMITED RESOURCES. FLAGYL IN A TRAVELER WOULD CURE POSS GIARDIA

MALABSORPTION

EXCESSIVE GAS, FLOATING STOOL, WEIGHT LOSS. IMPAIRED FAT DIGESTION—PANCREATIC INSUFFICIENCY. IMPAIRED FAT ABSORPTION—SB CROHN’S, CELIAC. CARB MALABSORPTION—LACTOSE, FRUCTOSE, SORBITOL. STOOL ELASTASE RATHER THAN FECAL FAT FOR STEATORRHEA. STOOL PH<5.5 SUGGESTIVE OF LACTOSE INTOL.

MALABSORPTION—PANCREATIC INSUFF

PAIN, WEIGHT LOSS, FLOATY/GREASY STOOL. USUALLY DUE TO CHRONIC PANCREATITIS

ALCOHOL, CYSTIC FIBROSIS, AUTOIMMUNE. STOOL ELASTASE <200 ug/g stool. CT EVAL FOR ATROPHY, CALCIFICATIONS. EUS EVAL FOR PARENCHYMAL AND DUCTAL CHANGES.

MALABSORPTION—CELIAC

TESTING THOSE WITH IBS, FE DEFIC, INFERTILITY, CHRONIC FATIGUE, FHX/SYMPTOMATIC.

OFTEN CONFUSED WITH IBS BECAUSE MANY LACK THE CLASSIC SX’S OF ANEMIA AND WEIGHT LOSS.

15-25% HAVE DERMATITIS HERPETIFORMIS BLISTERS. >2 MIL IN US, 1 IN 133 PERSONS, 1 IN 22 IF POS 1ST DEGREE

FHX. TTG IgA OR EMA IgA FOLLOWED BY DUODENAL BX FOR

CONFIRMATION. AVOID IgA ANTIGLIADIN AB, LOW ACCURACY. CAUTION: IgA DEFIC PTS AND GLUTEN RESTRICTION FALSE NEG

RESULTS.

MALABSORPTION—BACTERIAL OVERGROWTH

DUODENUM AND JEJUNUM USUALLY <100K org/ml PATHOPHYSIOLOGY QUITE COMPLEX:

DESYNCH OF MMC, LESS PERISTALSIS REDUCED GASTRIC/BILE/PANCREATIC/IG SECRETIONS IC VALVE REMOVAL ALLOW BACTERIAL REFLUX BACTEROIDES DECONJUGATE BILE ACID, AFFECT CARB

ABSORPTION CARB MALABSORPTION OSMOTIC DIARRHEA

DEFIC VIT A/B12/FOLATE/FE/CA++

MEDICATIONS

OSMOTIC: CITRATE, PHOSPHATE, SULFATE, ANTACIDS, SORBITOL.

SECRETORY: ABX, CHEMO, DIGOXIN, COLCHICINE, NSAIDS, PG.

MOTILITY: MACROLIDE, REGLAN, SENNA.

CHRONIC DIARRHEA

FUNCTIONAL—IBS SECRETORY—MICROSCOPIC, BILE ACID, POSTOP DUMPING INFLAMMATORY—IBD PARASITE—GIARDIA MALABSORPTION—PANCREATIC INSUFF, CELIAC, SIBO. MEDICATIONS—OSMOTIC/SECRETORY.**HISTORY ACCURACY IS CRITICAL.**MOST PRACTICAL TO CHARACTERIZE TYPE BEFORE TESTING AND TREATING.