Comparison of the efficacy of serum amyloid A, C-reactive protein, and procalcitonin in the diagnosis and follow-up of necrotizing enterocolitis in premature infants

Abstract Purpose The aim of this study was to compare the efficacy of serum amyloid A (SAA) with that of C-reactive protein (CRP), and procalcitonin (PCT) in diagnosis and follow-up of necrotizing enterocolitis (NEC) in preterm infants. Methods A total of 152 infants were enrolled into this observational study. The infants were classified into 3 groups: group 1 (58 infants with NEC and sepsis), group 2 (54 infants with only sepsis), and group 3 (40 infants with neither sepsis nor NEC, or control group). The data including whole blood count, CRP, PCT, SAA, and cultures that were obtained at diagnosis (0 hour), at 24 and 48 hours, and at 7 and 10 days were evaluated. Results A total of 58 infants had a diagnosis of NEC. Mean CRP (7.4 ± 5.2 mg/dL) and SAA (46.2 ± 41.3 mg/dL) values of infants in group 1 at 0 hour were significantly higher than those in groups 2 and 3. Although the area under the curve of CRP was higher at 0 hour in infants with NEC, there were no significant differences between groups with respect to the areas under the curve of SAA, CRP, and PCT at all measurement times. Levels of SAA decreased earlier than CRP and PCT in the follow-up of NEC (mean SAA levels were 45.8 ± 45.2, 21.9 ± 16.6, 10.1 ± 8.3, and 7.9 ± 5.1 mg/dL at evaluation times, respectively). Levels of CRP and SAA of infants with NEC stages II and III were significantly higher than those with only sepsis and/or NEC stage I. Conclusions Serum amyloid A, CRP, and PCT all are accurate and reliable markers in diagnosis of NEC, in addition to clinical and radiographic findings. Higher CRP and SAA levels might indicate advanced stage of NEC. Serial measurements of SAA, CRP, and PCT, either alone or in combination, can be used safely in the diagnosis and follow-up of NEC.