Lactobacillus rhamnosus bacteremia: an emerging clinical entity
Summary
Lactobacillus rhamnosus is the most frequent Lactobacillus species in clinical infections, often linked to nosocomial infections in immunocompromised patients with catheters.
Area of Science:
- Clinical microbiology
- Infectious diseases
- Bacteriology
Background:
- Lactobacillus species are common human commensals, rarely causing infections.
- Their pathogenic role is debated beyond infectious endocarditis.
- Clinical characterization of Lactobacillus infections is needed.
Purpose of the Study:
- To characterize clinically associated Lactobacillus species.
- To identify risk factors and patient profiles in Lactobacillus bacteremia.
Main Methods:
- Retrospective study of Lactobacillus isolates from 2004-2009.
- Identification using API Coryne, MALDI-TOF MS, 16S rRNA, and tuf gene sequencing.
- Polymerase chain reaction (PCR) assay as the gold standard.
Main Results:
- Lactobacillus rhamnosus was the most common species isolated (60 strains).
- L. rhamnosus bacteremia occurred in 16 patients in the study.
- Literature review identified 45 additional cases; 66% immunosuppressed, 83% had catheters.
Conclusions:
- Lactobacillus rhamnosus is a significant cause of bacteremia in clinical settings.
- Nosocomial infections, immunosuppression, and catheter use are key risk factors.
- Further research into Lactobacillus pathogenesis is warranted.
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