Proteus Mirabilis

Proteus mirabilis is a gram negative rod with swarming motility. It is facultative anaerobic bacterium having urease activity.

Pathogenesis

Route of entry
Proteus is responsible for community and hospitalized acquired urinary tract infection. It is present in colon and colonies urethra.

Virulence Factors

• Phenylalanine deaminase
• Urease
• O- antigen
• Pili
• Fimbriae for adherence
• Endotoxin

Predisposing factors
• I/V injections
• Urinary catheters
• Poor hygiene
• Malnutrition
• Young and elderly

Clinical symptoms
• UTI
• Pneumonia
• Wound infections
• Septicemia

Lab-Diagnosis

Specimen
• Urine
• Pus
• Sputum

Microscopy
• Gram- negative rods
• Facultative anaerobes
• Motile – swarming motility
• Non- encasulated
• Fimbriae

Culture

Blood agar
Swarming motility on blood agar

MacConkey agar
Non-lactose fermenting colonies, non-swarming because of bile salts

CLED
Non-lactose fermenting colonies, non-swarming because electrolyte deficient

Biochemical Tests

TSI Agar

• Slant Alkaline
• Butt Acidic
• Produces Gas
• Produces H2S

Catalase positive
Oxidase negative
Only ferments glucose, and sucrose
Reduces nitrate to nitrite
Urease positive
Phenylalanine deaminase positive
B- galactosidose negative
Indole negative

Serological Test
• PCR

Treatment

• Aminoglycosides
• Trimethoprim- sulfamethoxazole