A49-01 Case of Disseminated Acinetobacter Infection in a 70-Year-Old Male With Underlying Suspected TCell Lymphoma

Abstract Introduction Infections due to the Acinetobacter calcoaceticus-baumannii complex (ACB complex) can be devastating in immunocompromised patients. It can also be very aggressive and leave a short amount of time for treatment, which is challenging as ACB is becoming increasingly resistant at a rate of over 50%. About 2% of the healthcare-associated infections are caused by Acinetobacter, however this jumps to 7% among critically ill patients on mechanical ventilators per CDC numbers in 2013. Case A 70-year-old male with a medical history of atrial fibrillation (on rivaroxaban), hypertension, prostate cancer (in remission), osteoarthritis, diverticulosis, and prior gastrointestinal bleeding presented with bright red blood per rectum. He was hypotensive and tachycardic, admitted to the MICU, and imaging revealed pleural effusion, lymphadenopathy, and findings suggestive of malignancy. Subsequent workup revealed exudative pleural effusion, progressive disease, and cultures positive for multidrug-resistant Acinetobacter baumannii and Candida. While a biopsy-confirmed diagnosis was not obtained, flow cytometry findings suggested PTCL-NOS. Despite broad-spectrum antimicrobials, renal replacement therapy, and supportive care, he deteriorated, and the family elected for comfort measures. Discussion This case illustrates fulminant disseminated Acinetobacter calcoaceticusbaumannii complex infection in a patient with probable T-cell lymphoma (PTCL-NOS). Acinetobacter species, particularly the ACB complex, are highly virulent, multidrugresistant gramnegative coccobacilli responsible for a growing number of nosocomial and ventilatorassociated infections. They possess multiple virulence factors (porins, lipopolysaccharides, secretion systems, biofilm formation, and metal-acquisition systems) and demonstrate extensive antibiotic resistance mechanisms. In immunocompromised hosts, they can cause disseminated disease with high mortality. New therapeutic strategies—including β lactam/β lactamase inhibitor combinations (e.g., sulbactam-durlobactam), bacteriophage therapy, and monoclonal antibodies—represent promising directions for refractory MDR infections. Compared with published cases of Acinetobacter infection in immunocompromised hosts, this case is notable for the rapid dissemination, dual fungal-bacterial infection, and probable hematologic malignancy. Mortality in similar cases remains extremely high despite aggressive therapy. This abstract is funded by: None