Escherichia coli

Background

Clinical Features

Differential Diagnosis

Acute diarrhea

Infectious

Noninfectious

Watery Diarrhea

  • Enterotoxigenic E. coli (most common cause of watery diarrhea)[1]
  • Norovirus (often has prominent vomiting)
  • Campylobacter
  • Non-typhoidal Salmonella
  • Enteroaggregative E. coli (EAEC)
  • Enterotoxigenic Bacteroides fragilis

Traveler's Diarrhea

Evaluation

  • Stool culture
  • Rapid assay for Shiga toxin

Management of EHEC[2]

  • Supportive only
  • Do not treat with antibiotics (typically the same for ETEC)
    • Antibiotics do not alleviate symptoms, reduce carrier risk of organism, or reduce HUS risk
    • Ciprofloxacin may increase enterotoxin release
  • 7-14 days after infection, highest risk for HUS, which may need follow up and monitoring of:
    • Proteinuria
    • Hematuria
    • Red cell casts
    • Creatinine elevation

Antibiotic Sensitivities[3]

Category Antibiotic Sensitivity
Penicillins Penicillin G R
Penicillin V R
Anti-Staphylocccal Penicillins Methicillin R
Nafcillin/Oxacillin R
Cloxacillin/Diclox. R
Amino-Penicillins AMP/Amox I
Amox-Clav S
AMP-Sulb S
Anti-Pseudomonal Penicillins Ticarcillin I
Ticar-Clav S
Pip-Tazo S
Piperacillin S
Carbapenems Doripenem S
Ertapenem S
Imipenem S
Meropenem S
Aztreonam S
Fluroquinolones Ciprofloxacin S
Ofloxacin S
Pefloxacin S
Levofloxacin S
Moxifloxacin S
Gemifloxacin S
Gatifloxacin S
1st G Cephalo Cefazolin S
2nd G. Cephalo Cefotetan S
Cefoxitin S
Cefuroxime S
3rd/4th G. Cephalo Cefotaxime S
Cefizoxime S
CefTRIAXone S
Ceftaroline S
CefTAZidime S
Cefepime S
Oral 1st G. Cephalo Cefadroxil S
Cephalexin S
Oral 2nd G. Cephalo Cefaclor/Loracarbef S
Cefproxil S
Cefuroxime axetil S
Oral 3rd G. Cephalo Cefixime S
Ceftibuten S
Cefpodox/Cefdinir/Cefditoren S
Aminoglycosides Gentamicin S
Tobramycin S
Amikacin S
Chloramphenicol S
Clindamycin R
Macrolides Erythromycin R
Azithromycin R
Clarithromycin R
Ketolide Telithromycin R
Tetracyclines Doxycycline S
Minocycline S
Glycylcycline Tigecycline S
Daptomycin R
Glyco/Lipoclycopeptides Vancomycin R
Teicoplanin R
Telavancin R
Fusidic Acid R
Trimethoprim S
TMP-SMX I
Urinary Agents Nitrofurantoin S
Fosfomycin S
Other Rifampin R
Metronidazole R
Quinupristin dalfoppristin R
Linezolid R
Colistimethate S

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

References

  1. Marx et al. “Cholera and Gastroenteritis caused by Noncholera Vibrio Species”. Rosen’s Emergency Medicine 8th edition vol 1 pg 1245-1246.
  2. Bush LM and Perez MT. Infection by Escherichia coli O157:H7 and Other Enterohemorrhagic E. coli (EHEC). Merck Manual. http://www.merckmanuals.com/professional/infectious-diseases/gram-negative-bacilli/infection-by-escherichia-coli-o157,-c-,h7-and-other-enterohemorrhagic-e,-d-,-coli-(ehec)
  3. Sanford Guide to Antimicrobial Therapy 2014