Work

Chromobacterium haemolyticum Pneumonia Associated with Near-Drowning and River Water, Japan

Year: 2020

Type: article

Abstract: C hromobacterium is a genus of gram-negative, fac- ultative anaerobic bacteria; application of 16S rRNA gene sequencing into bacterial taxonomy is expanding its species (1-5).Most Chromobacterium infections in humans have been caused by C. violaceum (6).Recently, exceptionally rare cases of C. haemolyticum infections have been described (2,4,7-9), but environmental sources of this pathogen have not been well investigated.We describe a case of Chromobacterium-associated pneumonia due to near-drowning and environmental investigation of a river site of the near-drowning.We used whole-genome sequencing (WGS) to identify the Chromobacterium species causing pneumonia associated with near-drowning and investigate molecular features, including antimicrobial resistance, virulence, and genetic relatedness of clinical and environmental isolates of C. haemolyticum. The StudyThis study was approved by the institutional review board of Tohoku University Graduate School of Medicine (IRB no.2018-1-716).In June 2018, a man in his 70s was transported to our emergency center.He had altered consciousness and hypothermia at admission.He had fallen down a bank and into a river in the Tohoku region of Japan while intoxicated from alcohol and was found immersed in the river.He had respiratory failure and required intubation and mechanical ventilation.He had multiple fractures and a cervical cord injury.He had a history of hypertension, diabetes, and benign prostatic hyperplasia but was not immunodeficient.We diagnosed severe aspiration pneumonia and sepsis and treated the patient empirically with intravenous meropenem plus levofloxacin.We detected a nonpigmented, β-hemolytic gram-negative bacillus from both sputum and blood cultures.C. violaceum was identified by a matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry (VITEK MS; bioMérieux, https://www.biomerieux.com)with a confidence value of 99.9%.We changed the antimicrobial drug regimen to intravenous ceftazidime plus levofloxacin based on antimicrobial susceptibility testing pattern (Appendix 1 Table, https://wwwnc.cdc.gov/EID/article/26/9/19-0670-App1.pdf).After 3 weeks of intravenous therapy and critical care, the patient showed clinical improvement and had negative blood and sputum cultures.He was transferred to a community hospital for further rehabilitation and completed an additional 2 months of oral levofloxacin.In mid-August, we conducted an environmental investigation of the river water in the area where the patient was found.We collected 500 mL samples of river water, 2 samples at the site where the patient was found and 1 sample 4 km upstream, where he likely fell into the river.We filtered samples through a Chromobacterium haemolyticumPneumonia Associated with Near-Drowning and River Water, Japan

Source: Emerging infectious diseases

DOI: 10.3201/eid2609.190670