Melatonin as a Supportive Biomarker in Early-Onset Neonatal Sepsis: A Prospective Study

Area of Science:

• Neonatal Medicine
• Biochemistry
• Clinical Diagnostics

Background:

• Early-onset neonatal sepsis (EOS) presents diagnostic challenges due to nonspecific clinical signs.
• Blood cultures, the gold standard, can be falsely negative in EOS cases.

Purpose of the Study:

• To compare serum melatonin levels in term neonates with suspected EOS versus healthy controls.
• To assess melatonin's diagnostic performance against standard inflammatory markers for EOS.

Main Methods:

• Prospective case-control study of 84 term infants (42 suspected EOS, 42 controls).
• Collected blood cultures, CBC, CRP, and serum melatonin via ELISA within 24 hours of life.
• Performed Receiver Operating Characteristic (ROC) analyses for diagnostic evaluation.

Main Results:

• Significantly lower mean melatonin levels observed in suspected EOS cases compared to controls (193.5 vs 231.6 pg/mL, P=.010).
• Melatonin levels did not significantly differ between culture-positive and culture-negative EOS cases.
• ROC analysis for suspected EOS showed an AUC of 0.628; a cutoff of 242 pg/mL had 81% sensitivity but only 45.2% specificity.

Conclusions:

• Serum melatonin levels are lower in neonates with suspected EOS.
• Melatonin exhibits limited diagnostic specificity for EOS.
• Melatonin should be considered a supportive marker in a multimodal diagnostic approach for neonatal sepsis.