Klebsiella oxytoca: Clinical Infection and qPCR Detection

1. Morphology
K. oxytoca is a short, plump Gram-negative rod.

It is non-motile due to the absence of flagella but possesses a prominent polysaccharide capsule, which contributes to its virulence.

Many strains also express fimbriae (pili), aiding in adhesion to host tissues.

2. Culture Characteristics
This organism grows readily on standard laboratory media with minimal nutritional requirements.

On blood agar at 35–37°C for 18–24 hours, it forms large, moist, mucoid colonies, a key feature for preliminary identification.

K. oxytoca can cause infections in multiple organ systems, particularly in immunocompromised individuals.

1. Respiratory Infections
May lead to pneumonia, presenting with fever, cough, and sputum production.

2. Urinary Tract Infections
Associated with cystitis and pyelonephritis, with symptoms such as dysuria, urgency, and frequency.

3. Gastrointestinal Infections
Can cause antibiotic-associated diarrhea and other gastrointestinal disturbances.

4. Wound Infections
May infect surgical sites or traumatic wounds, especially in hospital settings.

The thick capsule enhances resistance to phagocytosis and contributes to persistence in host tissues.

As part of the normal flora, disruption of microbiota balance or weakened immunity can facilitate opportunistic infection.