Coagulase-Negative Staphylococci in Neonatal Blood: How Concerning?

Abstract

Objective Coagulase-negative staphylococci (CoNS) are being implicated as one of the leading causes of bloodstream infection (BSI). To study the spectrum, prevalence, and antimicrobial susceptibility of CoNS causing BSI in neonates. Materials and Methods A cross-sectional study was done in level III neonatal intensive care unit (NICU). Blood samples in automated culture bottles were processed as per the standard technique. Previously validated methods were followed for the characterization of CoNS and for AST of standard antibiotics by Kirby Bauer disk diffusion and vancomycin by agar dilution. The prevalence of causative organisms and susceptibility of CoNS were statistically analyzed. Categorical variables were compared by chi-square or Fisher's exact probability tests. Result In total, 1,365 blood samples (1,365 neonates) were studied, of which 383 (28.05%) were positive and 982 (71.94%) were negative. Gram-positive organisms (GPC) predominated (n = 238; 62.14%) (p < 0.001) with 41.77% (160/383) S. aureus and 13.83% (53/383) CoNS. CoNS included S. epidermidis (19, 38%), S. haemolyticus (7, 14%), S. hominis (6, 12%), S. simulans (6,12%), S. capitis (5,10%), S. cohnii (4, 8%), S. warneri (1, 2%), and S. xylosus (1, 2%). The susceptibility to netilmicin, linezolid, and vancomycin was 100% (p ≤ 0.001), and 54% (n = 27) had vancomycin MIC of 0.125 μg/mL but methicillin-resistant CoNS (MRCoNS) was 70%. Methicillin-susceptible (MS) CoNS had lower MIC of vancomycin (p < 0.05) than MRCoNS. Conclusion The spectrum of pathogens causing BSI in neonates is changing with predominance of GPC and among CoNS, S. epidermidis. Considerable proportion of MRCoNS with the emergence of MIC creep for vancomycin requires immediate attention.

Coagulase-negative Staphylococci – A True Pathogen in Bloodstream Infections and their Resistance Patterns in a Tertiary Care Hospital

“…17 In contrast, in the pediatric population, methicillin resistance was found to be 70% in the present study, which is very similar (70%) to that reported by Ansari et al, ranging from 40% to 100% among various CoNS species. 18 None of the isolates in the present study showed resistance to vancomycin and linezolid which was similar to previous studies, 19,20 where vancomycin-resistant CoNS detection was performed on various clinical isolates and nasal samples respectively.…”

A case of exudative pleuritis caused by Staphylococcus warneri

“…Such invasive infections caused by coagulase-negative staphylococci typically proceed less aggressively than those caused by Staphylococcus aureus, and are more prolonged over time. However, in recent years, they have become of increasing clinical importantance [10,11,12,13,14].…”