Can melatonin be used as a marker for neonatal sepsis?

BACKGROUND: Melatonin, an indolamine endogenously produced by pineal body, has important role as an anti-oxidant, anti-inflammatory and anti-apoptotic. Whether melatonin concentration changes in neonatal sepsis and whether it can be used as a marker of sepsis is unknown.

OBJECTIVE: The objective of this study is to evaluate melatonin concentration in the serum as a marker for neonatal sepsis and compare it to standard markers.

STUDY DESIGN: We prospectively studied 40 neonates: 20 diagnosed with late neonatal sepsis and 20 healthy neonates as a control group. Markers of sepsis and melatonin concentration were compared between both groups.

RESULTS: The sepsis groups had significantly increased immature to total neutrophils ratio (I/T ratio), and high sensitivity C-reactive protein (HsCRP), and decreased platelet count. Melatonin concentration was increased in sepsis group when compared to control group (27.2 ± 3.3 versus 11.4 ± 3.2 pg/ml, p = 0.001), and positively correlated with HsCRP (r = 0.952, p = 0.001) and I/T ratio (r = 0.326, p = 0.015). Combining melatonin to HsCRP increased sensitivity and specificity to detect neonatal sepsis to 97.3 and 93.3%, respectively.

CONCLUSIONS: Endogenous melatonin concentration is increased in late neonatal sepsis and can potentially be used as a marker for sepsis especially when combined with CRP.