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
INFLAMMATORY

USUALLY VIRAL OR TOXINS

INVASIVE BACTERIA

PROMOTE INTESTINAL SECRETION

DISRUPT MUCOSA.

LARGE VOLUME, NONBLOODY

FEVER, PAIN, LOW VOL, BLOODY.

NO FECAL LEUKOCYTES

FECAL LEUKOCYTES.

E. COLI, STAPH, GIARDIA, VIBRIO,

SALMONELLA, CAMPYLOBACTER,

BACILLUS CEREUS, C. PERFRINGENS,

SHIGELLA, E. COLI, C. DIFF.
CLUES TO DX OF ACUTE DIARRHEA
HISTORY
SOURCE
PATHOGEN
PAIN, BLOODY STOOL, AFEB.
RAW MILK, RAW BEEF,
TOXIGENIC E. COLI (265K)
BUFFET FRIED RICE SYNDROME
FRIED RICE AND SOIL
BACILLUS CEREUS (<100K)
MOUNTAINS, COUNTRYSIDE
UNTREATED WATER, CAMPING
GIARDIA (15K)
ASIA, INDIA RECENT TRAVEL
RAW SEAFOOD
VIBRIO (8K)
SALADS, CREAMY PASTRY,
SANDWICH
STAPH AUREUS (240K)
FOOD HANDLED WITHOUT
ADDITIONAL COOKING
RAW CHICKEN CONTAM.
UNDERCOOKED BEEF, PORK,
CHICKEN
FOOD SERVICE GERM
CAFETERIA, CATERED MEAT
(PRE-COOKED KEPT <140F)
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.