BACKGROUND: The Acinetobacter (A.) genus is a group of Gram-negative bacilli which mainly cause nosocomial infections or infections in immunocompromised patients. A. baumannii is the most common agent of human infection, and A. junii represents less than 3% of isolates. We present a rare case of A. junii bacteremia and pneumonia in an immunocompetent patient with no recent hospital admissions or antibiotic exposure.

CASE PRESENTATION: We report the case of a 78-year-old man with a three-day history of  shortness of breath, dry cough, and fever. Initial blood tests revealed leukocytosis and a raised C-reactive protein, while lung imaging showed right upper lobe consolidation. He was diagnosed with community-acquired pneumonia, rapidly evolving into respiratory failure and septic shock, necessitating mechanical invasive ventilation, vasopressor, and inotropic support. Blood cultures and cultures of tracheal aspirate were positive for A. junii. After the microbiology sensitivities were known, antibiotic therapy was changed to meropenem, resulting in a good clinical outcome and resolution of infection.

CONCLUSIONS: While A. junii is commonly a sensitive organism, there are reports of colistin and carbapenem resistance. It is important to document new presentations to expand our knowledge of this rare microorganism.