Plasma anti-myosin autoantibodies in the diagnosis of necrotizing enterocolitis

We aimed to assess whether autoantibodies can be used as biomarkers for necrotizing enterocolitis (NEC) and applied for its early diagnosis. A prospective observational study was conducted in neonates with suspected NEC abdominal distension (the developmental study), which consisted of 50 neonates finally divided into NEC (n = 24) and non-NEC (n = 26) cohorts based on follow-up results. Serum samples were collected within 48 h of illness onset and used for screening NEC-associated plasma autoantibodies by autoantigen microarray. Additionally, we validated anti-myosin autoantibodies by enzyme-linked immunosorbent assay (ELISA) in an independent validation study, for which we selected plasma samples within 48 h of onset of NEC (n = 38) and samples of gestational age- and weight-matched controls (n = 13). Autoantigen microarray revealed that both IgG and IgM anti-myosin autoantibodies in plasma from neonates with NEC were significantly higher than those in neonates with other diagnoses. ELISA showed that plasma anti-myosin autoantibodies increased in the NEC cohort, with 1.5-fold higher levels than in the non-NEC cohort. Anti-myosin autoantibodies were able to distinguish NEC from non-NEC, achieving an area under the curve (AUC) of 0.8856 (95% confidence interval (CI): 0.7918-0.9795), with sensitivity of 81.58% and specificity of 76.93%. Plasma anti-myosin autoantibodies were significantly higher in all three subtypes of NEC (P < 0.0001 for NEC I; P = 0.0018 for NEC II; P = 0.0011 for NEC III), especially in NEC stage I than that in the non-NEC controls.

Conclusion: Anti-myosin autoantibodies may be applied as a promising diagnostic marker for NEC, especially for NEC stage I.

What is known: • Intestinal damage and self-antigen exposure may lead to increased autoantibodies, and they are widely used as biomarkers for diagnosing inflammatory bowel disease. • Necrotizing enterocolitis (NEC) is a devastating disease with overwhelming inflammation and immune dysregulation.

What is new: • Increased autoantibodies were present in patients with NEC, even before typical X-ray manifestations. • Anti-myosin autoantibodies may be applied as a promising diagnostic marker for NEC.