Pseudomonas Mendocina Bacteremia: A Case Study and Review of Literature

Abstract

BACKGROUND Pseudomonas mendocina is a Gram-negative, aerobic, rod-shaped bacterium belonging to the family Pseudomonadaceae. In nature, P. mendocina has been isolated from water and soil samples. The species rarely causes disease in humans though severe infections resulting in hospitalization and intensive care have been documented. This case is perhaps the second reported case in the United States of a P. mendocina related infection. In this case report, we analyze the clinical and laboratory features of P. mendocina infection in a severely immunocompromised acquired immunodeficiency syndrome (AIDS) patient and review the available literature. CASE REPORT A 64-year-old white male with past medical history significant for human immunodeficiency virus (HIV)/AIDS (CD⁴ count on admission <10 cells/mm³) diagnosed in 1988 and on antiretroviral therapy since 1992, was admitted to our facility for acute management of a suspected invasive mold infection. On hospital day 20 the patient developed a fever of 39.9°C, had an elevated lactate of 2.6 mmol/L and absolute neutrophil count greater than 1000 cells/mm³. On hospital day 22, both blood culture sets were positive for Pseudomonas mendocina. Antibiotic therapy was de-escalated to ceftazidime and after a total treatment course of 10 days the was successfully discharged. CONCLUSIONS There have been 14 reported cases of P. mendocina in the world. Four cases presented with meningitis and 5 with endocarditis. Beyond typical anti-pseudomonal agents, 2 of the reported cases show susceptibility of P. mendocina antibiotics such as sulfamethoxazole/trimethoprim and ceftriaxone. All documented case reports of P. mendocina infection resulted in successful treatment with antibiotics and survival of the patient.