Evaluation of Achromobacter xylosoxidans subsp. denitrificans Infections at an University Hospital

Introduction: Infections due to Achromobacter xylosoxidans (AX) type bacteria are very rare. There are few case reports from our country but knowledge about practical therapeutical applications is scarce. In this study we aimed to report AX denitrificans infections and clinical approach at our hospital. Materials and Methods: This study comprised patients over 18 years old who were hospitalised at Manisa Celal Bayar University Hafsa Sultan Hospital and who were positive for AX. denitrificans between 01.01.2016-31.12.2019. Data about these patients were obtained retrospectively from hospital records. Demographic clinical and bacteriologic data were analysed by suitable methods. Results: AX. denitrificans was detected in 16 cultures of 10 patients. Growth was detected from wound biopsy cultures in 11 specimens (68.7%). Nine patients were male and the mean age was 51.3 +/- 17. Seven of the patients had been hospitalised in the same clinic at different time intervals. The most common diagnosis was surgical site infection. All of AX. denitrificans induced infections were health care associated infections (HAI). Risc factors were found as being hospitalised and/or operated at the plastic and reconstructive surgery ward, antibiotic consumption within the last month and history of collagen tissue disorders. At the time of diagnosis with AX. denitrificans infection, 10 patients were using ampirical antibiotic for vairous reasons. One patient passed away before culture result was obtained. The most common ampirical antibiotic was found as third generation cephalosporins. When culture results were identified in 50% of the patients were receiving appropriate antibiotherapy. All 16 culture growths revealed sensitivity towards piperacillin/tazobactam. Conclusion: Even though AX. denitrificans is a rare community and hospital derived infectious agent, it should be kept in mind in clinics that show clustering and suitable ampiric therapy should be applied to keep the infection under control.