Methicillin resistance & inducible clindamycin resistance in Staphylococcus aureus.

Background & objectives: Methicillin resistant Staphylococcus aureus (MRSA) isolates with inducible clindamycin resistance (iCR) are resistant to erythromycin and sensitive to clindamycin on routine testing and inducible clindamycin resistance can only be identified by D-test. This study was aimed to detect methicillin resistance and iCR among S. aureus isolates, effectiveness of some commonly used antibiotics and correlation between methicillin resistance and iCR. Methods: The present cross-sectional study included 46 S. aureus isolates subjected to Kirby-Bauer’s disk diffusion method for antibiotic susceptibility testing (AST) to estimate MRSA and resistance to some commonly used antibiotics. D-test was employed to detect iCR. Results: Eleven of the 46 (23.9%) isolates tested were MRSA. Overall, 19 (41.3%) isolates showed of iCR. Vancomycin and linezolid were found to be 100 per cent effective. A positive Karl-Pearson’s coefficient of correlation (0.89) between methicillin resistance and iCR was obtained. Interpretation & conclusions: Detection of iCR is important for the use of clindamycin in MRSA infections. Methicillin resistance and iCR appear to be clinically unrelated.

Hepatitis C and diabetes mellitus.

Hepatitis C virus infection in diabetes mellitus is more common than in non-diabetic population. Earlier it was thought to be due to more use of needles for insulin injections and frequent blood examination which has been recently antagonised by recent studies. Hepatitis C virus infection has shown to produce insulin resistance (because of liberated cytokines) insulin secretory defect (by viral infection or auto-immune damage). Hepatitis C virus infection also leads to non-alcoholic fatty liver disease (a probable component of insulin resistance syndrome) and increased iron increased iron storage in the body. All these factors may explain hepatitic C virus infection as an aetiology for diabetes mellitus. If future researches strongly establish this fact, antiviral or vaccines for hepatitis C virus infection should be thought of for preventing diabetes mellitus.

Diabetes and tuberculosis interface.

Diabetes mellitus is often complicated by acute or chronic infections, as it is a secondary immune deficiency disorder. Diabetes mellitus produces immune alterations of both cellular and humoral immunity. Tuberculosis in diabetes mellitus is 2-5 times higher. Chances of recurrence with multidrug resistant bacteria are common. More cavitary lesions, less sputum positivity and with relative paucity of symptoms and signs are the features. Treatment for diabetes mellitus should be done with insulin. Every diabetic person should be screened for tuberculosis and every tuberculosis patient should also be searched for diabetes.