Clinical manifestations and risk factors of community-onset Acinetobacter species pneumonia in Japan; case control study in a single institute in Japan

To clarify the etiology, patients' characteristics and risk factors for community-onset AP (Acinetobacter species pneumonia), we conducted this case-control study. We reviewed all patients with community-onset AP at our institute from 2010 until 2018. We defined non-AP group as a control. The patients with non-Acinetobacter spp. pneumonia (non-AP) were randomly selected during the study period without clinical information based on medical records' list among patients with community-onset pneumonia. The age (+/- 2 years) and sex were matched to the patients with community-onset AP, and the ratio was AP: non-AP group = 1: 3. Patients' characteristics, clinical outcomes, pathogens isolated and drug susceptibility were evaluated by comparing AP and non-AP group. The mean age of community-onset AP group was 79 years. They were 8 males and 5 females. The 30-day and in-hospital mortality rates of community-onset AP were 23% (v.s. 3%, p = 0.049) and 31% (v.s. 5%, p = 0.029) respectively, which are higher than the control group. Heavy alcohol consumption (23% v.v. 0%, p = 0.023), higher Charlson Comorbidity index (3.2 v.s. 2.0, p = 0.046) and lobar pneumonia by chest radiology (50% v.s. 23%, p = 0.071) were seen more frequently in community-onset AP than in the control group. In conclusion, community-onset AP shows poor outcomes despite the appropriate antibiotic therapy. Heavy alcohol history might be a risk factor of AP. Patients with community-onset AP could have more comorbidity and poor general conditions than the control group. (c) 2019 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights