Performance of Carbapenemase Nordmann-Poirel, Modified Carbapenem Inactivation, and EDTA Carbapenem Inactivation Methods for Detecting Carbapenem-Resistant Klebsiella pneumoniae Isolates.

Infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) are a major threat to public health. Timely detection of CRKP will help treat patients with appropriate antibiotics. This study aimed to evaluate the performance of the carbapenemase Nordmann-Poirel (CarbaNP), modified carbapenem inactivation (mCIM), and EDTA carbapenem inactivation (eCIM) methods for the detection of CRKP. We compared the results of the three assays with that of real-time PCR. In total, 195 K. pneumoniae isolates, including 150 carbapenem-resistant and 45 carbapenem-susceptible isolates, were investigated. Carbapenem-resistance genes, such as blaKPC, blaNDM, blaVIM, blaIMP, and blaOXA-48-like, were identified using real-time PCR. Among the 150 CRKP isolates, 94 (62.7%) were positive for blaNDM, 29 (19.3%) were positive for blaOXA-48-like, and 27 (18%) were positive for both blaNDM and blaOXA-48-like. For detecting CRKP isolates, CarbaNP, mCIM, and eCIM showed 96.0%, 95.4%, and 96.7% sensitivity, respectively, and all three methods showed 100% specificity. All three phenotypic confirmatory tests are reliable for identifying CRKP, easy to perform, cost-effective, and can be incorporated with routine antibiotic susceptibility testing.

Changing antibiotic resistance profile of Staphylococcus aureus isolated from HIV patients (2012-2017) in Southern India.

PURPOSE: Emergence of multidrug-resistant and methicillin-resistant Staphylococcus aureus (MRSA) infections in HIV patients limit the treatment options and challenge the clinical management of infections. The periodic monitoring of S. aureus infections and its drug resistance profile in HIV patients are of paramount importance in clinical management. MATERIALS AND METHODS: A total of 7204 clinical specimens from HIV patients from 2012 to 2017 were processed for the isolation of S. aureus strains using conventional culture techniques and cultures were identified using standard biochemical test. Antibiotic susceptibility of S. aureus strains was tested by Kirby-Bauer disk diffusion method. RESULTS: A total of 380 (5.3%) S. aureus strains were isolated from HIV patients in the study period. High percentage of S. aureus strains were isolates from urine (69.5%) specimen and 58.4% of S. aureus infections were noted among hospitalized patients. Antibiotic susceptibility profile reveals S. aureus was highly resistant to penicillin (95.2%) followed by cephalexin (84.6%). Methicillin resistance was highly observed in the year 2017 (86%) and the rate of MRSA steadily increasing from 51.8% in 2012 to 86% in 2017. Significant increase of S. aureus infections (35%; p<0.001) and MRSA (76%; p=0.0007) were observed in the year 2016. CONCLUSIONS: This study reports the increasing trends of S. aureus infections and MRSA among HIV patients from Southern India. Multidrug-resistance profile of S. aureus could complicate the selection of proper antibiotic regimens and time cure of HIV patients.

In vitro assessment on medicinal properties and chemical composition of Michelia nilagirica bark

Objective To outline the antibacterial, antioxidant, α-glucosidase inhibition and anticancer properties of Michelia nilagirica (M. nilagirica) bark extract. Methods The antibacterial activity of bark extracts against human pathogens was assessed by disc diffusion assay. Phytochemical screening, total phenols, flavonoids content, antioxidant and α-glucosidase inhibition properties of bark extracts were investigated by standard methods. In vitro anticancer activity of ethyl acetate extract at various concentrations was observed against HepG2 cells using MTT [3-(4, 5-dimethyl thiazol-2yl)-2, 5-diphenyl tetrazolium bromide] assay. The presence of diverse bioactive constituents in the ethyl acetate extract was identified using FT-IR and GC–MS analysis. Results Ethyl acetate extract was found to be the promising agent against human pathogens tested. The ethyl acetate extracts showed the presence of various phytochemicals and comprised the substantial content of phenolics and flavonoids. The ethyl acetate extract showed better antioxidant activities and also revealed remarkable reducing power ability and α-glucosidase inhibition property. The dose dependent assay of extract showed remarkable cancer cell death with IC