Shigella
Background
- Anaerobic, gram-negative rod
- Requires a very small inoculum to cause disease
Clinical Features
- Symptoms usually start within 1-3 days of exposure[1]
- Variation depends on serotype
- Can be anywhere from 12 hours to 7 days for incubation period
- Fever
- Diarrhea (can be bloody)
- Generalized abdominal pain
- In severe cases in children, can lead to seizures[2]
Differential Diagnosis
Acute diarrhea
Infectious
- Viral (e.g. rotavirus)
- Bacterial
- Campylobacter
- Shigella
- Salmonella (non-typhi)
- Escherichia coli
- E. coli 0157:H7
- Yersinia enterocolitica
- Vibrio cholerae
- Clostridium difficile
- Parasitic
- Toxin
Noninfectious
- GI Bleed
- Appendicitis
- Mesenteric Ischemia
- Diverticulitis
- Adrenal Crisis
- Thyroid Storm
- Toxicologic exposures
- Antibiotic or drug-associated
Watery Diarrhea
- Enterotoxigenic E. coli (most common cause of watery diarrhea)[3]
- Norovirus (often has prominent vomiting)
- Campylobacter
- Non-typhoidal Salmonella
- Enteroaggregative E. coli (EAEC)
- Enterotoxigenic Bacteroides fragilis
Traveler's Diarrhea
Management
Adult
- Antibiotics
- Not essential, since infection clears spontaneously in most individuals
- However, most favor antibiotic therapy for patients with positive stool culture[4]
- First line is fluroquinolone (e.g. Cipro 500mg PO BID x 7 days)
Antibiotic Sensitivities[5]
Key
- S susceptible/sensitive (usually)
- I intermediate (variably susceptible/resistant)
- R resistant (or not effective clinically)
- S+ synergistic with cell wall antibiotics
- U sensitive for UTI only (non systemic infection)
- X1 no data
- X2 active in vitro, but not used clinically
- X3 active in vitro, but not clinically effective for Group A strep pharyngitis or infections due to E. faecalis
- X4 active in vitro, but not clinically effective for strep pneumonia
Table Overview
| ||||||||||||||||||||||||||||||||||||||||
See Also
External Links
References
- ↑ Missouri Department of Health and Senior Services. Shigellosis. Last revised June 2017. https://health.mo.gov/living/healthcondiseases/communicable/communicabledisease/cdmanual/pdf/Shigella.pdf
- ↑ Lahat E, Katz Y, Bistritzer T, Eshel G, Aladjem M. Recurrent seizures in children with Shigella-associated convulsions.External Ann Neurol. 1990;28(3):393-5.
- ↑ Marx et al. “Cholera and Gastroenteritis caused by Noncholera Vibrio Species”. Rosen’s Emergency Medicine 8th edition vol 1 pg 1245-1246.
- ↑ Dupont HL. Shigella species (bacillary dysentery). In: Principles and Practice of Infectious Diseases, 6th Ed, Mandell GL, Bennett JE, Dolin R (Eds), Churchill Livingstone, Philadelphia 2005. p.2655.
- ↑ Sanford Guide to Antimicrobial Therapy 2014