Carbapenamase OXA-23 like-producing Acinetobacter baumanii epidemic outbreak in a hospitalization unit

Abstract

Carbapenamase OXA-23 like-producing Acinetobacter baumanii epidemic outbreak in a hospitalization unit

Background: Despite its great ubiquity and morbidity and mortality, the scientific evidence on the hospital control of multiresistant Acinetobacter baumanii (ABMR) outside the Intensive Care Units in Spain is scarce. The objective was to describe an epidemic outbreak by MRAB and analyze the effectiveness of the actions carried out.

Methods: Prospective observational study of admitted-rotated patients in a multipathological control at the University Hospital of Guadalajara, Spain, during the outbreak (September 20-November 3, 2017); using Mambrino Electronic Health Record. A genetic study of the resistance mechanism and molecular characterization of the strains were carried out. Frequency measurements were estimated, with subsequent comparative analysis of cases vs controls.

Results: The median age of the study population (N=138) was 83.2 years (Interquartile Range [IR]=69.7-90.1). There were 3 cases of ABMR infection among them. Thirteen percent required issolation, 17% because of MRAB. The MRAB incidence was 2.2 cases/100 admitted-rotated (mortality rate=33%). The excess stay for cases was 17±4.3 (95%CI=8.5-25.6), with an incidence density of 3 cases/10³ days. The responsible strain was carbapenemase OXA-23. We found a single case in the colonization study of contacts. No MRAB was isolated from environmental samples.

Conclusions: Along with epidemiological research, coordination and compliance with precautions; prompt identification and management of an outbreak are crucial to minimize the colonization pressure and to stop dissemination.