Catheter-related bloodstream infection due to Tsukamurella pulmonis identified by MALDI-TOF spectrometry, 16S rRNA gene sequencing, and secA1 gene sequencing in an immunocompromised child: a case report and literature review.

Tsukamurella species are Gram-positive bacilli related to aerobic Actinomyces. Originally reported from the environment, Tsukamurella species have also been described in human infections, especially in bacteremia. A literature review analysis revealed that Tsukamurella spp. are often initially considered as contaminant microorganisms, especially due to bacterial identification issues. Here, we report a catheter-related bloodstream infection in an immunocompromised child caused by Tsukamurella pulmonis. Matrix-Assisted Laser Desorption/Ionization-Time Of Flight (MALDI-TOF) mass spectrometry allowed rapid genus-level identification and contributed to better patient care. However, accurate species-level identification required 16S rRNA gene sequencing and secA1 gene sequencing. Considering the increased number of Tsukamurella infections, the implementation of new Tsukamurella species in MALDI-TOF databases is required to be more discriminant.