ABSTRACT
Introduction: This study attempts to generate preliminary data regarding post-COVID pulmonary fungal infections, namely, COVID-19-associated pulmonary aspergillosis (CAPA), COVID-19-associated pulmonary mucormycosis (CAPM), and mixed infections from the Himalayas and compares the micro-radio-clinical profile and outcomes of the affected patients. Materials and Methods: A retrospective data analysis was conducted, where clinical profiles, microbiological and radiological reports, and outcomes of n = 16 patients of post-COVID pulmonary infections were compared. Results: Of n = 16 patients, n = 7 had CAPA (n = 5 Aspergillus fumigatus, n = 1 Aspergillus flavus, and n = 1 Aspergillus niger), n = 5 CAPM (Rhizopus arrhizus), and n = 4 with mixed infections (n = 3 infected with Aspergillus fumigatus and Rhizopus spp. and n = 1 with Aspergillus flavus and Rhizopus arrhizus). Thick-walled cavitary lesions, air-fluid levels, and multiple centrilobular nodules were some of the common radiological findings reported among these patients. Conclusion: The immuno-compromised state following COVID-19 infection and treatment might be responsible for the progression of regular exposure to the dense Himalayan vegetation into an invasive pulmonary fungal infection. Suspecting post-COVID pulmonary fungal infection is necessary for primary care physicians to ensure timely referral to higher centers. Mixed pulmonary fungal infections (coinfection with Aspergillus spp. and Rhizopus spp.) are also emerging as important sequelae of COVID-19.
ABSTRACT
PURPOSE: The purpose is to explore the diagnostic utility of colistin broth disk elution (CBDE) as a simple and reliable method of colistin susceptibility testing. MATERIALS AND METHODS: An exploratory study was undertaken in a tertiary care teaching hospital in Uttarakhand, from September 2021 to March 2022, after obtaining approval from the Institute Ethics Committee. Twenty-five non-repetitive carbapenem-resistant Klebsiella pneumoniae clinical isolates were included in the study. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) and BD Phoenix M50 system were used to perform species-level identification and antibiotic susceptibility testing (AST), respectively, as per the manufacturer's instructions. AST results (including those of colistin) were interpreted as per the CLSI guidelines 2022. The test isolates were further subjected to additional in vitro colistin susceptibility testing using a commercially available Mikrolatest colistin susceptibility testing kit and CBDE, respectively. RESULTS: The in vitro colistin resistance rates varied from 8% by BD Phoenix system to 20% by Mikrolatest kit and 32% by CBDE, respectively. For colistin susceptibility, a higher CA was observed between the BD Phoenix system and CBDE (64.71%) than between the Mikrolatest kit and CBDE (31.60%). Overall, a statistically significant fair agreement was observed between the BD Phoenix system and CBDE (Kappa: 0.312; 95% CI: 0.036 to 0.660) and Mikrolatest MIC colistin kit and CBDE (Kappa: 0.286; 95% CI: 0.111 to 0.683), respectively. CONCLUSIONS: In vitro colistin testing remains a significant challenge globally. Although the present study results are inconclusive due to the small sample size, we should conduct multi-centric studies globally, taking a considerable sample size representing different Gram-negative bacilli to generate conclusive evidence on the utility of CBDE as a reliable method of colistin susceptibility testing.
ABSTRACT
BACKGROUND: There is a lack of whole-genome sequencing (WGS) data on multidrug-resistant (MDR) bacteria from the Uttarakhand region of India. The aim of this study was to generate WGS data of carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates recovered from patients in Uttarakhand's tertiary care centre. METHODS: A cross-sectional study included 29 MDR K. pneumoniae test isolates obtained from various clinical samples submitted to the bacteriology laboratory for culture and sensitivity testing from July 2018 to August 2019. After preliminary identification and antibiotic susceptibility testing, these isolates were subjected to WGS. RESULTS: A total of 27 of 29 isolates were CRKP. ST14 was the most common sequence type (n=8 [29.6%]). Carbapenem resistance was mainly encoded by OXA-48-like genes (21/27 [77.8%]). All isolates had a varied arsenal of resistance genes to different antibiotic classes. KL2 (9/27 [33.3%]) and KL51 (8/27 [29.6%]) were dominant K loci types. O1 and O2 together accounted for 88.9% (n=27) of CRKP isolates. Genes encoding yersiniabactin (ybt) and aerobactin (iuc) were identified in 88.9% (24/27) and 29.6% (8/27) of isolates. The predominant plasmid replicons present were ColKP3 (55.5%), IncFII(K) (51.8%) and IncFIB(pQil) (44.4%). CONCLUSIONS: This study emphasises the need for continued genomic surveillance of MDR bacteria that could be instrumental in developing treatment guidelines based on integrating phenotypic and molecular methods.
