Prevalence of methicillin-resistant staphylococcus-aureus in neonatal sepsis and detection of other accompanied diagnostic markers

ABSTRACT

This study was carried out in Neonatal Intensive Care Unit [NICU] Tanta University Hospital over a period of one year on 70 neonates diagnosed as neonatal sepsis and a control group composed of 10 neonates having physiological jaundice only. Blood cultures were done for patients and MRSA was detected using oxacillin and cefoxitin disc diffusion, oxacillin agar screening and dilution methods. Blood samples were tested for total leucocytic count and for C-reactive protein and serum samples were tested by ELIZA for Soluble IL-2 receptor [sIL-2R]. Staph. aureus was detected in 15% of early onset and 60% in late onset sepsis. In early onset sepsis, MRSA was detected in 33.3% by oxacillin disc diffusion method, agar screening method and in 66.7% using agar dilution and cefoxitin disc diffusion methods. In late onset sepsis MRSA was detected in 38.9% by oxacillin disc diffusion, 44.4% by agar screening, and 83.3% by agar dilution and cefoxitin disc diffusion methods. sIL-2R had a high ability to confirm the diagnosis of early neonatal sepsis, i.e. its sensitivity was high [85%]. This ability to confirm positive cases was more profound in late onset sepsis [96.7%]. Using the ROC curve for comparison between sIL-2R and CRP revealed that sIL-2R is more diagnostic, while comparing sIL-2R with TLC proved that the latter is more diagnostic. In Conclusion, MRSA is becoming a problem in our NICU. Cefoxitin disc diffusion as well as oxacillin agar dilution methods are reliable predictors of MRSA. As a diagnostic marker for infection, sIL-2R is useful especially when combined with CRP and TLC