Methods: Prospective observational unmasked study. Blood samples were collected at onset of symptoms from infants diagnosed with NEC, IP and matched controls admitted to NICU of Women and Infants Hospital of RI. Infants with NEC were diagnosed by Bell's staging criteria (all had ≥ stage 2 or 3). Infants with IP were diagnosed by clinical and radiological findings. Infants in the control group had non-specific abdominal disorders but no radiographic evidence of NEC or IP and no disease progression. Controls were matched for gestational age, gender and weight. Plasma IAI and CRP levels were quantified using competitive enzyme-linked immunosorbent assay with intra-assay variability (coefficient of variation) of <3% . Mean biomarker levels were subjected to analysis of variance and post-hoc analysis.
Results: There were 28 infants studied in three groups.
|Varibale||NEC (n=5)||IP (n=6)||Controls (n=17)||P-value|
|Gestational age, weeks*||275±34||264±15||275±26||0.64|
|Age at presentation, days*||12.2±11.5||8.1±4.8||10.2±7.1||0.11|
|Birth weight, grams*||1025±705||825±243||1067±570||0.69|
|Gender, male %||20%||66%||35%||0.25|
|IAI at onset, µg/ml*||139 ± 21||319 ± 72||276 ± 110||0.01|
|CRP at onset, ng/ml*||18.4 ± 24.9||15.8 ± 9.6||6.9 ± 14.2||0.27|
Plasma IAI levels were significantly lower in infants with NEC at onset when compared to those with IP and matched controls (p<0.004 and p<0.01 respectively). In contrast, plasma CRP levels were not different among infants with NEC, IP and matched controls at disease onset (P 0.27).
Conclusion: As a biomaker, IAI may assist in early detection of NEC from controls and differentiate NEC from IP at disease onset. IAI has higher discrimination than that of CRP. This differentiation at disease onset may lead to earlier effective treatments, antimicrobial stewardship and improved outcomes.
J. Padbury, None