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Bacteraemia caused by Actinobaculum schaalii: An overlooked pathogen?
Johanna Sandlund1, Martin Glimåker, Anita Svahn
1From the 1 Infectious Diseases Unit, Department of Medicine Solna, Karolinska Institute.
Scandinavian Journal of Infectious Diseases
|May 21, 2014
Summary
Actinobaculum schaalii, a difficult-to-culture uropathogen, can cause serious bloodstream infections. Clinicians should consider this bacterium in treatment-failure urinary tract infections to ensure proper diagnosis and treatment.
Area of Science:
- Medical Microbiology
- Infectious Diseases
- Bacteriology
Background:
- Actinobaculum schaalii is a Gram-positive, facultative anaerobic bacterium.
- It is a recognized, yet often overlooked, cause of urinary tract infections (UTIs).
- This pathogen exhibits intrinsic resistance to common antibiotics like ciprofloxacin and trimethoprim-sulfamethoxazole.
Observation:
- A. schaalii requires prolonged culture durations and specific growth conditions.
- Its fastidious nature leads to overgrowth by commensal bacteria, complicating laboratory detection.
- Consequently, A. schaalii is frequently misidentified or dismissed as normal flora.
Findings:
- A review of 17 cases of A. schaalii bacteremia highlights its significant invasive potential.
- Bacteremia cases were associated with underlying conditions such as urinary tract abnormalities and immunosuppression.
- Treatment failure in UTIs may indicate the presence of A. schaalii.
Implications:
- Healthcare providers must maintain a high index of suspicion for A. schaalii in complicated UTIs and urosepsis.
- Diagnostic laboratories should employ methods to improve the detection of this challenging pathogen.
- Accurate identification is crucial for appropriate antimicrobial therapy and improved patient outcomes.
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