Clinicomicrobiological Profile and Antibiotic Susceptibility Pattern of Burkholderia cepacia Complex Isolates from a Tertiary Care Hospital in Southern India: A Cross-sectional Study

Abstract

Introduction: Burkholderia cepacia Complex (BCC) is a group of Gram negative betaproteobacteria with complex taxonomy that causes healthcare-associated infections and hospital outbreaks. BCC is the fourth most pathogenic non fermentative Gram negative bacilli worldwide, following Burkholderia cepacia, Acinetobacter baumannii, and Stenotrophomonas maltophilia, with a prevalence ranging between 10-20% for non fermentative Gram negative bacilli and 5-15% for BCC. Human infections are caused by 22 known species and 14 novel species. Pulmonary BCC infections lead to “Cepacia syndrome,” a fatal illness that results in progressive respiratory failure and necrotising pneumonia, leading to early death in 20% of cases. Aim: To emphasise the disease burden and clinical outcomes of BCC infections, as well as to assess the performance of various methods for BCC detection. Materials and Methods: A cross-sectional study was conducted at PSG Institute of Medical Sciences and Research, Coimbatore, Tamil Nadu, India. A total of 91,778 samples were received between April 2021 and December 2022, over a period of one year and nine months, to determine the disease burden of BCC. The identification of BCC was carried out using manual culture and sensitivity, VITEK®-2 ID/AST system, Matrix Assisted Laser Desorption Ionisation-Time of Flight Mass Spectrometry (MALDIToF-MS), recA gene virulence determinant by Polymerase Chain Reaction (PCR), and 16S Ribosomal ribonucleic acid (rRNA) sequencing. Out of 115 manually identified BCC isolates, 56 (48.70%) underwent automated Vitek® 2 ID/AST, MALDI-ToF-MS, recA gene PCR, and 16S rRNA sequencing for identification and characterisation. The results were entered into Microsoft Excel, and statistical analysis was performed using the International Business Machines (IBM) Statistical Package for the Social Sciences (SPSS) software version 28.0. Results: Culture positivity was observed in 16,949 samples (18.47%), among which 3,387 (29.25%) were non fermentative gram negative bacilli. The incidence of Burkholderia spp. isolation was 115 (3.4%) out of 3,387 non fermentative gram negative bacilli. The prevalence of BCC among the study population was 115 (0.13%) out of 91,778. Conclusion: BCC, causing a wide array of infections, results in profound morbidity and mortality, especially in hospital settings. Early identification using Vitek-2 and MALDI-ToF-MS, along with molecular methods like PCR and 16S rRNA sequencing, could be the key to confirming the diagnosis and initiating appropriate management.