Emergence of Unusual Gram - Negative Bacteria Among Cancer Patients in a Tertiary Care Cancer Centre at North Kerala

Abstract

Patients with cancer are at a high risk of infection and often the focus of the infection is not apparent. Blood- stream infections (BSIs) have been the leading complications in such patients. Bacteria are the primary causative agents of BSIs. However, in recent years, unusual gram-negative bacteria i.e. Stenotrophomonas, Burkholderia, Elizabethkingia, etc., have emerged as potential human pathogens in cancer patients. Hence, the current study was performed to analyze the unusual GNB and their antibiotic susceptibility profile in BSIs among cancer patients in a tertiary care cancer centre. This retrospective study was conducted at a tertiary care cancer centre at North Kerala. We analyzed microbiological profile of blood cultures received in the Microbiology Division from January 2016 to December 2017. All the blood cultures were processed by using automated blood culture system (Bactec 9050). The positive cultures were analyzed by automated identification and susceptibility systems (ViteK 2 compact). During the 2-year period, a total of 4154 blood cultures were done out of which 385 (9.2%) cultures yielded growth. Overall, 15 different species (n = 27/385; 7%) of unusual GNB pathogens was found from 385 positive cases. Burkholderia cepacia complex (n = 4) is the most common species followed by Pseudomonas putida (n = 3), Chryseobacterium gleum (n = 3), etc. This study revealed the emergence of unusual GNB as potential drug-resistant nosocomial pathogens in patients with cancer.

Keywords

• Unusual Gram-negative bacteria
• Cancer patients
• Antibiotic resistance