Sequential Acinetobacter lwoffii Bacteremia and Early Carbapenem-Resistant Acinetobacter baumannii Pneumonia in Diabetic Ketoacidosis: A Case Report.

Acinetobacter lwoffii (A. lwoffii) is traditionally considered a low-virulence commensal organism, yet it can cause invasive infections in immunocompromised hosts. The sequential appearance of A. lwoffii bacteremia with carbapenem-resistant Acinetobacter baumannii (A. baumannii) (CRAB) infection in the same patient is rarely reported and presents unique diagnostic and therapeutic challenges. We describe a case of a 51-year-old male with underlying diabetes mellitus and a background of chronic alcohol use who presented with septic shock secondary to bilateral pneumonia, complicated by underlying diabetic ketoacidosis (DKA). Admission blood cultures grew A. lwoffii bacteremia with pan-susceptibility except for colistin resistance. Deep endotracheal aspirate cultures later grew extensively drug‑resistant A. baumannii. The patient received sequential targeted antimicrobial therapy comprising meropenem for A. lwoffii bacteremia with the addition of colistin for CRAB pneumonia, alongside aggressive supportive care, resulting in complete recovery and discharge. This report highlights the pathogenic potential of A. lwoffii in diabetic patients with metabolic decompensation and emphasizes the importance of recognizing mixed Acinetobacter infections in critically ill patients. Timely microbiological diagnosis and appropriate antimicrobial therapy are essential for favorable outcomes.