Proteus

Background

Microbiology

• Genus of Gram-negative bacilli that are oxidase negative and urease positive
• Part of the flora of the urinary and genital tracts as well as gastrointestinal tract
• Species of medical importance include Proteus mirabilis, Proteus vulgaris, and Proteus penneri
• Intrinsically resistant to tetracyclines, tigecycline, nitrofurantoin, and colistin
  • Proteus penneri and Proteus vulgaris are also intrinsically resistant to ampicillin, and first- and second-generation cephalosporins

Clinical Manifestations

• Urinary tract infection
  • Urease produces alkaline environment that can cause struvite stones
• Wound infections
• Pneumonia
• Bacteremia