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Introduction: During the second wave of coronavirus disease 2019 (COVID-19), superinfection caused by fungus and multidrug-resistant bacteria worsened the severity of illness in COVID-19 patients. Limited studies from India reported the antimicrobial resistance pattern of secondary infections. In this study, we aim to study the epidemiology of pathogens causing superinfections and genotyping of Gram-negative isolates in COVID-19 patients. Methods: This retrospective study was conducted at a dedicated COVID-19 center, India. The identification of bacteria/fungi was done by Vitek2® and matrix-assisted laser desorption/ionization-time of flight mass spectrometry system. Identification of beta-lactamase genes was done using thermal cycler. The diagnosis of mucormycosis was based on 10% potassium hydroxide direct microscopy. Statistical analyses were performed using STATA version 15.1 (StataCorp., College Station, TX, USA). For continuous variables, mean and standard deviation were computed. For comparing proportions of secondary infections across admission location and outcomes, the Chi-squared test of independence was used. To compare the mean and median between intensive care units and outcomes, an independent t-test and a Mann–Whitney test were used. Results: Of all the clinical samples, 45.4% of samples were cultured positive for secondary infections. Acinetobacter baumannii (35%) was the most common Gram-negative pathogen, while among Gram positive, it was Enterococcus faecium (40%). Among fungus, Candida spp. (61%) predominates followed by molds. Colistin and tigecycline proved effective against these pathogens. blaNDM was the most prevalent gene followed by the blaOX among the carbapenemase genes. Conclusions: The mortality rate among COVID-19 patients with secondary infection was significantly higher compared to the overall mortality rate in COVID-19 patients.

Introduction: Tests detecting SARS-CoV-2-specific antigen have recently been developed, and many of them are now commercially available. However, the real-world performance of these assays is uncertain; therefore, their validation is important. In this study, we have evaluated the performance of STANDARD F COVID-19 antigen fluorescence immunoassay (FIA) kit. Methods: Nasopharyngeal samples collected from patients were subjected to the test as per manufacturer's instructions. The performance of the kit was compared with the gold standard real-time polymerase chain reaction. Results: A total of 354 patients were tested with STANDARD F COVID-19 antigen FIA test kit. The overall sensitivity, specificity, positive predictive value, and negative predictive value of this test were found to be 38%, 99%, 96.2%, and 72%, respectively, with a diagnostic accuracy of 75.7%. Conclusion: STANDARD F COVID-19 antigen FIA showed high specificity and positive predictive value but low sensitivity and negative predictive value.

Introduction: MBL containing genes have been reported in all GNBs including Acinetobacter spp since 1990s which are worrisome as they are transmitted by mobile genetic elements. Thus, early detection of MBL encoding organisms is necessary. The current study was designed to identify the most sensitive cost-effective test which could be used as a screening test for detection of cabapenamase producing Acinetobacter isolates. Methodology: All consecutive strains of Acinetobacter spp isolated from various clinical samples were included. All isolates found resistant to any of the carbapenems were tested for MBL production using MHT (on MacConkey Agar and Mueller Hinton Agar), Etest (using Imipenem/Meropenem-EDTA) and Combined Disc Test (using EDTA and 2 MPA as inhibitors and Ceftazidime/Imipenem/Meropenem as substrate discs). PCR was performed for representative strains for IMP, VIM, KPC, OXA and NDM-1 gene. Results: Total of 154 non-duplicate strains of Acinetobacter spp were isolated and identified, of which, 134 (88%) and 126 (82%) were resistant to meropenem and imipenem respectively. All 134 meropenem resistant strains were tested for MBL production and PCR was performed on 100 strains. 3(3%), 5(5%), 7(7%), 26(26%), and 51(51%) strains had IMP gene, VIM gene, KPC gene, OXA gene and NDM-1 gene. MHT on MAC had better performance than on MHA and dilution to 0.05 McFarland was not required. Conclusion: MHT on MAC had best sensitivity when compared with gold standard PCR and was also cost effective. With ROC curve, we found that 2MPA was not a good MBL inhibitor when compared with EDTA..

The purpose of this study was to estimate the prevalence and to characterize the carbapenemase-producing Escherichia coli by various phenotypic antimicrobial susceptibility testing methods, and its performance was compared to the gold standard genotypic method. The prevalence of carbapenemase-resistant E. coli was found to be 65%. The phenotypic methods evaluated are cost-effective and can be used in resource-limited laboratories to rule out carbapenem resistance.

Drug resistance to Pseudomonas sp. has spread to such a level irrespective of the type of patients, that its pattern of distribution and antibiotic resistance needs to be studied in detail, especially in trauma patients and hence the study. A 6 year study was carried out among trauma patients to see the trend and type of resistance prevalent in the apex hospital for trauma care in India among nonduplicate isolates where multidrug-resistance (MDR), cross-resistance and pan-drug resistance in Pseudomonas sp. were analyzed. Of the total 2,269 isolates obtained, the species, which was maximally isolated was Pseudomonas aeruginosa (2,224, 98%). The highest level of resistance was seen in tetracycline (2,166, 95.5%, P < 0.001) and chloramphenicol (2,160, 95.2%, P < 0.001) and least in meropenem (1,739, 76.7%, P < 0.003). Of the total, 1,692 (74.6%) isolates were MDR in which P. aeruginosa (75%) were maximum. MDR Pseudomonas is slowing increasing since the beginning of the study period. Of 1,797 imipenem-resistant P. aeruginosa isolated during the study period, 1,763 (98%) showed resistance to ciprofloxacin or levofloxacin, suggesting that cross-resistance may have developed for imipenem due to prior use of fluoroquinolones. Antibiotic resistance in Pseudomonas sp. is fast becoming a problem in trauma patients, especially in those who requires prolong hospital stay, which calls for proper antimicrobial stewardship.

Soft tissue and wound infections due to Enterococcus spp. are increasing worldwide with current need to understand the epidemiology of the Enterococcal infections of wounds. Hence, we have looked into the distribution of Enterococcus spp. responsible for causing wound and soft tissue infections among trauma patients, its antibiotic resistance pattern and how it affects the length of hospital stay and mortality. A laboratory cum clinical-based study was performed over a period of 3 years at a level I trauma center in New Delhi, India. Patients with Enterococcal wound and soft tissue infections were identified using the hospital data base, their incidence of soft tissue/wound infections calculated, drug resistance pattern and their possible risk factors as well as outcomes analyzed. A total of 86 non-repetitive Enterococcus spp. was isolated of which E. faecium were maximally isolated 48 (56%). High level of resistance was seen to gentamicin HLAR in all the species of Enterococcus causing infections whereas a low level resistance to vancomycin and teicoplanin was observed among the isolates. Longer hospital stay, repeated surgical procedure, prior antibiotic therapy and ICU stay were observed to associate with increased morbidity (P < 0.05) and hence, more chances of infections with VRE among the trauma patients. The overall rate of wound and soft tissue infections with Enterococcus sp. was 8.6 per 1,000 admissions during the study period. Enterococcal wound infection is much prevalent in trauma care facilities especially in the ICUs. Here, a microbiologist can act as a sentinel, help in empirical therapeutic decisions and also in preventing such infections.