There is a significant difference in prevalence and antibiotics sensitivity of Staphylococcus aureus infections across the world [1]. Reports available regarding the epidemiology of S. aureus in India are scarce, especially in the pediatric population [2,3]. This observational study was conducted from August 2014 to September 2015 at Institute of Child Health, Kolkata, India. Hospitalized children (age 0-18 y) with culture-positive S. aureus infection were included in the study. Cases from out-patient department were excluded. Ethical clearance was obtained from the institutional ethics committee.

Blood, pus, cerebro-spinal fluid (CSF) or other body fluids (pleural, pericardial and joint fluids) were collected from patients having suspected infection, and sent for culture and sensitivity. After informed written consent, data were collected for age, sex, clinical features and antibiotic sensitivity pattern. Infections were defined as community acquired (CA), hospital acquired (HA) and Healthcare-associated Community-onset (HACO) [4]. Isolates were identified and antibiotic sensitivity was tested as per Clinical and Laboratory Standards Institute guidelines [5].

A total of 1017 specimens collected from admitted patients during study period showed culture positivity. Of these, 13% (n=125) were positive for Staphylococcus species; 52.8% (n=66) were S. aureus and 47.2% (n=59) were CONS. Of the total CONS, 33 isolates were positive within 24 hours, of which 48.5% (n=16) were in neonates. Clinico-epidemiological data of included children is presented in Table I.

TABLE 1 	Profile of Staphylococcus Aureus Infection in Our Study

In 2013, Indian Network for Surveillance of Antimicrobial Resistance (INSAR) reported proportion of methicillin-resistant S. aureus (MRSA) between 22%-68% in Indian hospitals [6]. Contrary to the rising trends of MRSA, it was documented in only 16.7% patients in our study, most of which was CA-MRSA (n=8). Community acquired infections (75.8%, n=50) out-numbered hospital acquired infections in our study, similar to that reported by Eshwara, et al. [3].

All Staphylococcus isolates in our study were sensitive to Vancomycin, Linezolid and Teicoplanin. Methicillin-sensitive S. aureus (MSSA) were also sensitive to Amikacin, Gentamycin and Levofloxacin. Clindamycin resistance (inducible + constitutional) among MSSA, MRSA, CA-MRSA was 60%, 81.8% and 87.5%, respectively. Shenoy, et al. [7] showed about 22.9% CA-MRSA clindamycin resistant in India, which was considerably less than our study. We also saw increased resistance of MSSA, MRSA and CA-MRSA towards Co-trimoxazole, Erythromycin, Ciprofloxacin and Ofloxacin similar to findings by Eshwara, et al. [3].

Our study had limitations of a small sample size. We also could not test for SCC mecA gene and PVL toxins. Rational antibiotic policy to prevent the rise in resistant staphylococci is the need of the hour.

Acknowledgements: Joydeep Das (Assistant professor), Prabal Niyogi (Deputy Director), Dolly Kalita (Post graduate trainee) and Surupa Basu (Assistant Professor, Department of Biochemistry) who were involved at various stages with valuable inputs, data collection and statistical analysis.

Contributions: MKM, DM, SP: in data collection and conceptualizing the study; RK: supervised the study; MKM, DM: manuscript writing. All the authors approved the manuscript.

Funding: None; Competing interest: None stated.

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3. Eshwara VK, Munim F,　Tellapragada C,　Kamath A,　Varma M,　Lewis LE, et al. Staphylococcus　aureus bacteremia in an Indian tertiary care hospital: Observational study on clinical epidemiology, resistance characteristics, and carriage of the Panton-Valentine leukocidin gene. Int J Infect Dis.　2013;17:e1051-5.

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