Clinicomicrobiological Profile of Infections by Achromobacter: An Emerging Nosocomial Pathogen in Indian Hospitals.

Background: Achromobacter causes opportunistic nosocomial infections in immunocompromised patients with high mortality. It is underreported as it is often misidentified by conventional microbiological methods.

Aims: The aim of the study is to access the clinicomicrobiological profile and antibiogram of Achromobacter spp. from clinical isolates.

Materials and methods: It is an observational study done from July 2020 to December 2021 in our hospital. All nonduplicate isolates of Achromobacter from blood and respiratory samples were initially identified with VITEK-2 GN card system and further confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Antibiogram and treatment outcomes were also studied.

Results: Achromobacter spp. was isolated from 14 patients. Blood samples yielded most isolates (71.4%; n = 10) followed by tracheal aspirate and bronchoalveolar lavage fluid. Bacteremia followed by pneumonia was the most common clinical manifestation of Achromobacter infection. All the isolates were identified as A. xylosoxidans denitrificans and showed 100% susceptibility to minocycline and piperacillin-tazobactam. Diabetes mellitus and malignancy were the most common underlying condition in these patients. A favorable outcome was seen in 78.6% of the individuals with timely institution of antibiotics and proper diagnosis.

Conclusion: Infections due to Achromobacter are on the rise in developing countries like India. Resistance to many classes of antimicrobials makes its treatment more challenging therefore it should always be guided by antibiograms. The present study highlights the significance of this rare bacterium in patients with malignancies in India and advocates greater vigilance toward appropriate identification of this organism.