Burkholderia vietnamiensis causing a non-lactational breast abscess in a non-cystic fibrosis patient in Tamil Nadu, India

Species distribution and antimicrobial susceptibility of Burkholderia cepacia complex isolates in clinical infections: Experience from a tertiary care hospital, Southern India

PURPOSE

Burkholderia cepacia complex (Bcc) is a diverse group of environmental bacteria associated with opportunistic infections. The identification of Bcc using conventional methods poses challenges. Bcc infections are difficult to treat due to intrinsic antibiotic resistance. The study aimed to investigate the species distribution and antimicrobial susceptibility of clinical Bcc isolates.

METHODS

A total of 153 Bcc isolates obtained from clinical samples were analysed. Species identification was carried out using automated methods, including MALDI-TOF MS and VITEK2. Antimicrobial susceptibility testing was performed using the disc diffusion method.

RESULTS

Burkholderia cenocepacia (70.5%) emerged as the most prevalent species, followed by Burkholderia contaminans (9.8%) and Burkholderia cepacia (7.2%). Ventilator-associated pneumonia (38.6%) was the most common infection, followed by sepsis (28.1%). Co-existence of Bcc with other pathogens in many cases suggested potential co-infection scenarios. Antimicrobial susceptibility revealed that ceftazidime, co-trimoxazole and meropenem were the most effective drugs, while levofloxacin proved to be the least effective. Moderate susceptibility was noted to minocycline, with 4.6% of isolates exhibiting multi-drug resistance.

CONCLUSION

This study provides valuable insights into the prevalence, clinical associations, and antibiotic susceptibility of Bcc in India. It highlights the importance of Bcc as a nosocomial pathogen, especially in vulnerable patient populations. The findings contribute to understanding Bcc infections, their distribution, and emphasize the necessity for accurate identification methods in clinical settings.

Burkholderia cepacia Induced Occipital Subcutaneous Abscess and Fracture in a Brain-Dead Woman

Burkholderia cepacia is an aerobic opportunistic Gram-negative pathogen that mainly infects immunodeficiency patients. However, soft tissue infections with fractures due to Burkholderia cepacia are rare with no cases reported. Here, we report a rare case of 3 years of brain death in a 43-year-old woman with Burkholderia cepacia resulting in an occipital subcutaneous abscess and fracture. Through the second-generation sequencing of the whole genome of this strain, it was found that there were no high virulence genes and virulence factors. The patient received targeted antibiotic therapy and showed improvement in clinical symptoms and radiological signs. Bone destruction because of Burkholderia cepacia is easily overlooked due to the lack of characteristic symptoms and limited clinical examination. This case reminds us that Burkholderia cepacia without major virulence factors could damage the bone in immune-compromised patients.

Burkholderia vietnamiensis infection in a haematological unit: Case series and review of literature of this new emerging pathogen

Burkholderia vietnamiensis causes opportunistic infection in immunocompromised individuals. It closely resembles other non-fermentative Gram-negative bacteria. Accuracy in diagnosis has improved with the use of new modalities. Here, we describe four patients of lymphoblastic disorder on chemotherapy, who presented with fever due to blood stream infection. Multidrug resistant B. vietnaminensis was isolated in blood culture and identified using MALDI-TOF MS. All of them responded to a switch in antibiotic therapy based on sensitivity reports. This is the first case series from North India highlighting the importance of this less known organism as an important pathogen in immunocompromised patients.

Comparative analysis of different methods used for molecular characterization of Burkholderia cepacia complex isolated from noncystic fibrosis conditions

PURPOSE

Burkholderia is a Gram-negative opportunistic bacterium capable of causing severe nosocomial infections. The aim of this study was to characterize Burkholderia cepacia complex and to compare different molecular methods used in its characterization.

METHODS

In this study, 45 isolates of Burkholderia cepacia complex (Bcc) isolated from clinical cases were subjected to RAPD (Random amplified polymorphic DNA), recA-RFLP (Restriction fragment length polymorphism), 16SrDNA-RFLP, whole-cell protein analysis, recA DNA sequencing and biofilm assay.

RESULTS

Of the 45 isolates tested, 97.7% were sensitive to ceftazidime, 82.2% were sensitive to Cotrimoxazole, 73.3% were sensitive to meropenem, 55.5% were sensitive to minocycline and 42.2% were sensitive to levofloxacin. Majority of the isolates harbored all the tested virulence genes except bpeA and cblA. The RAPD generated 11 groups (R1-R11), recA-RFLP 10 groups (A1-A10), 16SrRNA-RFLP 5 groups (S1-S5) and SDS-PAGE (Sodium Dodecyl Sulphate-Polyacrylamide gel electrophoresis) whole cell protein analysis revealed 12 groups (C1-C12). recA sequencing revealed that most of the isolates belonging to the genomovar III Burkholderia cenocepacia. Though all the methods are found to be efficient in differentiating Burkholderia spp., recA-RFLP was highly discriminatory at 96% similarity value. The study also identified a new strain Burkholderia pseudomultivorans for the first time in the country. Further, recA sequencing could identify the strains to species level. Majority of the multidrug-resistant strains also showed moderate to strong biofilm-forming ability, which further contributes to the virulence characteristics of the pathogens.

CONCLUSIONS

The study highlights the importance of combination of molecular methods to characterize Burkholderia cepacia complex. Molecular typing of these human pathogens yields important information for the clinicians in order to initiate the most appropriate therapy in the case of severe infections and to implement preventive measures for the effective control of transmission of Burkholderia spp.