Diagnostic Value of Serum Amyloid A in Neonatal Sepsis: A Literature Review

Neonatal sepsis remains a major cause of morbidity and mortality worldwide, while early diagnosis is challenging due to nonspecific clinical manifestations and the limited accuracy of currently available biomarkers. Serum amyloid A (SAA), a rapidly responding acute-phase protein, has emerged as a potential adjunctive biomarker. This review searched PubMed/MEDLINE, the Cochrane Library, and the Directory of Open Access Journals to identify original studies published between 2000 and 2026 evaluating SAA’s diagnostic value in neonatal sepsis. Study quality was assessed using QUADAS-2. Following screening of 281 records, 13 studies comprising 1827 neonates were included. Due to methodological heterogeneity and limited availability of comparable diagnostic accuracy data, findings were synthesized qualitatively. Reported diagnostic performance was highly variable, with specificity generally higher than sensitivity and area under the receiver operating characteristic curve values ranging from approximately 0.60 to above 0.90. In studies evaluating kinetic patterns, SAA demonstrated earlier rise and more rapid decline compared with C-reactive protein. Relatively high negative predictive values were observed in some studies of preterm infants with late-onset sepsis, suggesting potential utility as a rule-out marker in selected contexts. Despite substantial heterogeneity, SAA appears promising as an adjunctive biomarker, although further standardized prospective studies are required before routine clinical implementation.