Peritonitis by Sphingobacterium mizutaii

Sphingobacterium mizutaii is an environmentally distributed bacterium; morphologically, it is a Gram-negative, non-glucose-fermenting, strictly aerobic bacillus that occasionally causes infections in humans, especially in immunocompromised and elderly patients. We present the clinical case of a 73-year-old man with multiple pathologies and dependence in activities of daily living referred from his health center for presenting with atrial fibrillation (AF) and COVID-19, in whom Sphingobacterium mizutaii was isolated from peritoneal fluid cultured in blood culture bottles after an incubation period of 31 h. This microorganism was isolated and identified by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS). Antibiogram was performed by disk diffusion and was susceptible to cotrimoxazole and levofloxacin. In conclusion, the summary of this clinical case will try to provide useful information to better understand this pathogen and its microbiological characteristics, as there is little literature on the subject.