Validation of MALDI-TOF MS devices in reanalysis of unidentified pathogenic bacteria detected in blood cultures

Lysinibacillus fusiformis bacteremia: Case report and literature review

A 93-year-old woman was diagnosed with Lysinibacillus fusiformis bacteremia complicated with coma blisters. Initial gram staining for L. fusiformis indicated the presence of gram-negative rods; however, subsequent staining of colonies from Mueller-Hinton agar revealed the presence of gram-positive and gram-negative rods with spherical endospores, and Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (VITEK ® MS and microflex® LT/SH) definitively identified the organism as L. fusiformis. The two-week administration of piperacillin/tazobactam and ampicillin resulted in an improvement of the patient's general condition, and the skin lesions gradually improved.

Leifsonia aquatica: Case report and literature review

Non-diphtheria Corynebacterium species have been increasingly recognized as multidrug resistant pathogens that also infect immunocompromised patients. Automated and semi-automated phenotypic tests have been used by clinical laboratories for detection of these gram-positive rods. The present case report describes the rare pediatric case of L. aquatica isolated in central venous catheter blood cultures during chemotherapy treatment for Wilms tumor and adds to the knowledge on this infection with regard to pediatric cancer. The clinical aspects of this patient and opportunities for improving treatment were reviewed. Additionally, a review of the literature revealed no other case report involving cancer and a pediatric patient with documented L. aquatica bacteremia. Corynebacterial infections are considered uncommon, but in recent decades' reports on infection with bacterium are increasing in frequency, particularly in nosocomial immunocompromised patients.