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Purpose: To study the infections caused by methicillin resistant Staphylococcus aureus (MRSA) with emphasis on heterogeneous vancomycin intermediate S. aureus (hVISA) in diabetic and non-diabetic patients and their comparison. Patients and Methods: S. aureus strains isolated from diabetic and non-diabetic patients admitted in four tertiary care hospitals in Coastal Karnataka, South India, were tested for methicillin resistance and included in the present study. Demographic and clinical data of the patients were collected using structured proforma. Antimicrobial susceptibility testing was done using the Kirby-Bauer disc diffusion method, and MLSB phenotypes were identified using the D-test. The minimum inhibitory concentration (MIC) of vancomycin was determined using agar dilution. MRSA isolates were tested for hVISA using vancomycin screen agar and population analysis profile – area under the curve (PAP-AUC) test. Statistical analysis of the results was done using the chi-square test. SPSS version 29.0 was used for this purpose. Results: Out of 665 strains of S. aureus isolated, 220 (33.1%) were MRSA. Of these 220 MRSA strains, 122 (55.5%) and 98 (44.5%) were isolated from diabetic and non-diabetic patients, respectively. There was no significant difference in the antimicrobial resistance patterns of MRSA strains isolated from diabetic and non-diabetic patients. Foot infections and osteomyelitis caused by MRSA were significantly more among diabetic patients. Out of 220 strains of MRSA, 14 (6.4%) were hVISA. The rates of hVISA among MRSA isolated from diabetic and non-diabetic were 9.0% and 3.1%, respectively. This difference was statistically not significant. Conclusion: The rate of hVISA among all MRSA isolates was 6.4%. The risk of hVISA infection was three times more in diabetic patients. The results emphasize the importance of the detection of hVISA among MRSA isolates especially from diabetic patients. [ABSTRACT FROM AUTHOR]

Background Blood stream infections (BSIs) due to Gram-positive pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) are associated with high mortality ranging from 10 to 60%. The current anti-MRSA agents have limitations with regards to safety and tolerability profile which limits their prolonged usage. Levonadifloxacin and its oral prodrug alalevonadifloxacin, a novel benzoquinolizine antibiotic, have recently been approved for acute bacterial skin and skin structure infections including diabetic foot infections and concurrent bacteremia in India. Methods The present study assessed the potency of levonadifloxacin, a novel benzoquinolizine antibiotic, against Gram-positive blood stream clinical isolates (n = 31) collected from January to June 2019 at a tertiary care hospital in Mumbai, India. The susceptibility of isolates to antibacterial agents was defined following the Clinical and Laboratory Standard Institute interpretive criteria (M100 E29). Results High prevalence of MRSA (62.5%), quinolone-resistant Staphylococcus aureus (QRSA) (87.5%), and methicillin-resistant coagulase-negative staphylococci (MR-CoNS) (82.35%) were observed among bacteremic isolates. Levonadifloxacin demonstrated potent activity against MRSA, QRSA, and MR-CoNS strains with significantly lower minimum inhibitory concentration MIC 50/90 values of 0.5/1 mg/L as compared with levofloxacin (8/32 mg/L) and moxifloxacin (2/8 mg/L). Conclusion Potent bactericidal activity coupled with low MICs support usage of levonadifloxacin for the management of BSIs caused by multidrug resistant Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

Objectives: Staphylococcus aureus causes a variety of symptoms and diseases and has been associated with high morbidity and mortality. A global population drift in clinical S. aureus isolates towards reduced antimicrobial susceptibility is being reported. In this study, the antimicrobial susceptibility profile and minimum inhibitory concentration (MIC) creep of vancomycin, linezolid, teicoplanin and rifampicin against clinical S. aureus isolates at an Indian tertiary centre from January 2012 to December 2016 were investigated., Methods: All consecutive, non-duplicate S. aureus isolates (n=1466) recovered from hospitalised patients identified by VITEK ® 2 were included in the study. Clinical isolates were tested against 20 antibiotics and were evaluated according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Statistical significance of the MIC creeps of four antimicrobials (vancomycin, linezolid, teicoplanin and rifampicin) was ascertained., Results: S. aureus isolates recovered from all clinical samples demonstrated high resistance to ampicillin, ciprofloxacin and penicillin (75-100%) and low resistance to amikacin, linezolid, netilmicin, nitrofurantoin, teicoplanin and vancomycin (0-13%). The MIC 90 values (MIC required to inhibit 90% of the isolates) for vancomycin, linezolid and rifampicin decreased, whereas the MIC 90 for teicoplanin increased. The change in the geometric mean MIC of rifampicin was found to be statistically significant. A statistically significant and progressive MIC creep was observed for teicoplanin and rifampicin., Conclusion: Despite remaining susceptible, S. aureus is not inert to antibiotic pressure. Implementation of preventive measures in healthcare settings is required worldwide to combat the increasing number of infections by this pathogen., (Copyright © 2018 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.)