Enterococcus casseliflavus: Clinical Significance and PCR Detection

1. Morphology and Structure
Cells are spherical to ovoid (0.6–2.0 μm × 0.6–2.5 μm), typically arranged in pairs or short chains.

It is non-spore-forming, Gram-positive, and may exhibit motility in some strains due to flagella. No prominent capsule is observed.

2. Physiological and Biochemical Features
E. casseliflavus is a facultative anaerobe with chemoheterotrophic metabolism.

It ferments a wide range of carbohydrates, producing primarily L(+)-lactic acid without gas formation.

Catalase-negative, weak nitrate reduction, typically lactose-fermenting, and classified within Lancefield group D.

3. Environmental Adaptability
Growth occurs between 10°C and 45°C, with an optimum at 37°C.

It tolerates harsh conditions including pH 9.6, 6.5% NaCl, and bile-rich environments, supporting its survival across diverse ecological niches.

4. Genetic Features
DNA G+C content ranges from 37–45 mol%, serving as an important taxonomic marker.

Widely distributed in nature, particularly within the gastrointestinal tract of vertebrates.

Transmission is primarily via fecal-oral routes, with additional presence in water, soil, and contaminated food.

1. Infection Types
Includes urinary tract infections, skin and soft tissue infections, intra-abdominal infections, and severe systemic infections such as bacteremia, endocarditis, and meningitis.

2. Symptoms
Common symptoms include persistent fever, elevated white blood cell count, rash, and site-specific manifestations (e.g., dysuria in UTIs, abdominal pain in intra-abdominal infections).

3. High-Risk Groups
Elderly patients, individuals with chronic diseases, immunocompromised patients, those receiving broad-spectrum antibiotics, and long-term hospitalized patients (especially ICU).

4. Neonatal Risk Factors
Immature immune systems, exposure during delivery, vertical transmission, and hospital-acquired infections contribute to neonatal susceptibility.

1. Personal Hygiene
Strict hand hygiene before patient contact, specimen handling, and food preparation.

Maintain clean clothing and reduce bacterial colonization risk.

2. Food Safety
Use fresh and hygienic ingredients, avoid expired or contaminated food, and prevent cross-contamination during preparation.

Store food at low temperatures to inhibit bacterial growth.

3. Environmental Sanitation
Regular disinfection of high-touch surfaces, medical devices, and shared environments.

Healthcare facilities should implement strict terminal disinfection protocols to reduce nosocomial infection risk.