DIARRHEA  &  GASTROENTERITIS

Overview:

1. Diarrhea can be caused by virus, parasites, funghi, bacteria, food intolerance, metals (zinc, cooper,  mercury), radiation, IBD, CF, recent chemotherapy (neutropenic diarrhea - "typhlitis"), HIV-enteropathy, Hepatitis A, TB.
    
2. Pts on antacids, broad-spectrum antbx are susceptible to diarrheas.
    
3. Diarrhea can present with N/V/D - gastroenteritis , without or with bloody stool -dysentery. Fever may or may not indicate enteric fever.
    
4. Diarrhea can be further classified into noninflammatory (noninvasive) and inflammatory (invasive).
    
   Noninflammatory is generally caused by enterotoxine that doesn't disrupt intestinal mucosa and is not associated with fecal leukocytosis. Common offenders are: V. cholera, V. parahaemolyticus, Rotavirus, Norwalk, E. Coli ( enterotoxin type), Cryptosporidium, Staph. aureus. Frequently large fluid quantity is lost.
   
   Inflammatory diarrhea is caused by organisms that invade mucosa. Fever, dysentery and abdominal  cramps  are common. Fecal leukocytes are present. Common offenders are: Salmonella, Shigella, Yersinia, C. diff, Campylobacter, E.Coli (enteroinvasive type).
    
5. In ER only presumptive diagnosis can be made. ER personnel should assess fluid status (orthostasis, BP, pulse, cap refill), stools hemoccult. IV hydration with LR or NS is provided. Common lab test are: CBC to see if pt has  in WBC, SMA to r/o electrolyte abnormality. Pts commonly have contraction metabolic alkalosis.
    
6. Stool for culture and  Ova/Parasite should be sent. Routine cultures include only Salmonella, Shigella, Campylobacter.  Special test such as C. diff  toxin is requested prn.  If no fever, no WBC, pt can tolerate PO hydration, no underlying medical problems that could be worsened by gastroenteritis, pts can be D/C home with instruction to have in fluid intake and avoid anti-diarrheal agents. Stool forming agents such as Attapulgite (Keopectate) and Bismuth salicylates (pepto-bismol) are preferred.  PO fluid must contain glucose. This helps intestinal absorption of  Na+.  One must be careful in prescribing opioides to patients with hx of COPD/Asthma, glaucoma.   Antibiotics are usually not needed since most gastroenteritis are 2ry  to virus or  from preformed toxin. If antibiotics are prescribed, Cipro 500 mg BID x 3 days is sufficient until culture results are available.
    
7. Note! As  stated  above, here we mention only infectious causes of diarrhea. Other causes of diarrhea in the differential  are: IBD, diverticulitis, drugs, intrabdominal mass/abscess, radiation, food intolerance etc.

Specific Causes of  Diarrhea:

	Source	Onset	D	N/V	F	Other S&S	DX	RX	Com
Bacillus cereus	Fried rice, Meat	1-6 h	+	+	-	-	Sp	S
Camplylobacter jejuni	Poultry	24h-5d	bloody in 50%	+/-	+	Ha,flu, myalgia	R	C	*
C. Diff	Antbx	days to wks	Guaiac (+) but rarely bloody	+/-	+	-	**	V/M	Tox Megac
C. perfringens	Poultry, Meat	6-24h	+	+/-	+/-	-	***	S
Ciguetera	Fish	24-48h	+	+	-	Neur/CV†	-	S	Neu
E. Coli O157:47 (enterohemorrahic)	Meat, Water	3-4d	bloody	+	+/-	-	Sp	S	TTP, hemorcoli
E. Coli ETEC (enterotoxinogenic)	Food (50% of Tr.diarrhea	-	+	+	+/-		Sp	S/C
Giardia (protozoa)	Food, Water	1-14 d	+	+	Flatu- lance	OP	M
Listeria	Food	days- wk.	+	+/-	+	HA, myalgia Arthralgia	Sp	Ampen
Norwalk (Virus)	Shellfish	24-48h	+	+	+/-	Flu-like	-	S
Rotavirus (common in children)	Virus	2-4h	+	+	+/-	-	-	S
Salmonella	Poultry, eggs milk	6-24h	+/-	+	++	bradycardia	R	C	§
Scombroid	Tuna, mahimahi	10-30m in	+	+/-	-	histamine- like	-	AH
Shigella	Water, Food	48-72h	Bloody	+	+	Neuro§	R	C	HUS §
Staph. aureus	Milk, ham egg, poultry	1-6h	+	+	-	-	-	S
V. cholerae	Food		rice water	++	+		Sp	S/DXC	Dehy Elec imb
V. parahaemolyticus	Seafood	12-24h	+	+	+			S
Yersinia	Pork, milk		bloody	+	+	RLQ Pain that mimics Appendicitis
Travelers Diarrhea	Water, Vegetables		+	=/_	-		Sp	C
Neutropenic enteropathy= "typhlitis	Neutropenic patient.  Clostridium commonly involved		+	+/-	+/-	RLQ Pain	Bld  & Stool	IVF Antbx or Surgery

 

HIV Related Diarrhea:

HIV enteropathy

CMV, Cryptosporidium, HSV, Isospora, MAI, venereal, Kaposi - can be diagnosed by cultures, biopsy, and sigmoidoscopy.  D/N/V/F are all common  presenting  S&S.  Latest literature for proper selection of antimicrobials is suggested due to continuous advances in this field.  Many HIV(+)ve patients have diarrhea with negative work-up. These patients are treated with Loperamide (Imodium) 2-4 mg PO after each loose BM.

 

Legend:

*    Complications are reactive arthritis, cholecystitis, Guillain-Barre, UTI, malaise  of  1-2 wks.

**   Toxin detection and sigmoidoscopy to identify pseudomembranes are commonly used  for diagnosis.

***  High spore count in pt's stool.  Patient experiences paresthesias, hot and cold dissociation, periorbital numbness, bradycardia, hypotension.  Above described neurological symptoms may persist for 1-2 wks.  Reactive arthritis (Reiter's), carrier state, osteomyelitis in SC are all possible complications.  Pts may experience peripheral neuropathy and in children seizure commonly  occurs.

AH=antihistaminic, C = cipro 500mg bid x 3 day, Compl = complications, D = diarrhea, Dx =diagnosis, DXC = doxycycline 300 gr. x1, F = fever, N/V = nausea, vomiting,  OP = ova/parasites, R = routine, Rx = treatment, S =supportive, Sp = special media for culture, V = vancomycin 125 mg qid x 7d, M= metronidazole 250 mg qid, HUS =hemolytic uremic syndrome.

BACK