Enterobacteriaceae-KLEBSIELLA, Enterobacter, and SERRATIA

Enterobacteriaceae-KLEBSIELLA, Enterobacter, and SERRATIA

KLEBSIELLA PNEUMONIAE

• Gram-negative, bacilli
• Have thick capsule
• Member of normal flora of colon
• Free-living in soil and water
• 10% carrier rate in upper respiratory tract
• Have multiple pili - help in adherence to respiratory and urinary epithelium

DISEASES BY K. PNEUMONIAE
An opportunistic pathogen
1. Lobar pneumonia
• In immunosuppressed host
thick mucoid sputum
2. Urinary tract infections

LAB IDENTIFICATION
Culture on Mackonkey agar
• Lactose fermenter & mucoid colonies
Citrate +ve
Indole –ve
TSI: Butt-acidic, Slant-acidic
Nonmotile

TREATMENT
• Among the most resistant of all enterobactericiae to antimicrobials especially for Beta-lactam antibiotics.

ENTEROBACTER

• Gram-negative, motile rods
• Lactose fermenter
• Mucoid colonies on MacConkey Agar
• An opportunistic pathogen
• Citrate +ve
• Antibiotic sensitivity - similar to Klebsiella

SERRATIA

- Late lactose fermenter
• Distinctive brick red colonies by some strains (red colonies on Nutrient agar medium)
• Opportunistic pathogen (hospital-acquired infection)
- Resistant to commonly used antibiotics like ampicillin