Early differential diagnosis between acute inflammatory demyelinating polyneuropathy and acute-onset chronic inflammatory demyelinating polyneuropathy in children: Clinical factors and routine biomarkers.

To identify clinical factors and biomarkers that could contribute to early differential diagnosis of acute inflammatory demyelinating polyneuropathy (AIDP) and acute-onset chronic inflammatory demyelinating polyneuropathy (A-CIDP) in the pediatric population, with limited evidence. We conducted an observational retrospective study of children diagnosed with AIDP and A-CIDP between January 2014 and December 2022. Demographic data, clinical features, and routine biomarkers were also analyzed. Statistical analysis was used to identify significant features with high sensitivity and specificity. We included 91 AIDP and 17 A-CIDP patients. The A-CIDP group had an older median age (6.33 vs. 4.33 years, p = 0.017), required more complex immunotherapies (p < 0.001), and showed a longer time to nadir over 2 weeks (76.5 % vs. 7.7 %, p < 0.001). Gastrointestinal dysfunction (29.4 % vs. 6.59 %, p = 0.014) and numbness (35.3 % vs. 12.1 %, p = 0.027) were more prevalent in A-CIDP. The AIDP patients had a longer median hospitalization stays (13 vs. 11 days, p < 0.05), more prodromal events (90.1 % vs. 64.7 %, p = 0.013), and more frequent cranial nerve palsy (61.5 % vs. 5.88 %, p < 0.001). The disability scores on admission, discharge, and peak were worse in the AIDP group (p < 0.001). AIDP patients showed higher cerebrospinal fluid protein (p = 0.039), albumin quotient (p = 0.048), leukocytes (p = 0.03), neutrophils (p = 0.010), platelet count (p = 0.005), systemic inflammatory index (SII) (p = 0.009), and gamma-glutamyl transferase (p = 0.039). Multivariable regression identified two independent predictors of early A-CIDP detection: time from onset to peak beyond 2 weeks (OR = 37.927, 95%CI = 7.081–203.15) and lower modified Rankin Scale score on admission (OR = 0.308, 95%CI = 0.121–0.788). Our study found that when the condition continued to deteriorate beyond two weeks with a lower mRS on admission and possibly less cranial nerve involvement, we may favor the diagnosis of pediatric A-CIDP rather than AIDP. • The time to nadir beyond 2 weeks and lower mRS on admission are the strongest predictors of A-CIDP compared to AIDP. • A-CIDP were older, needed complex immunotherapies, showed slower progression, and had more gastrointestinal issues and numbness. • AIDP showed more cranial nerve palsy and higher CSF protein, Qalb, leukocytes, neutrophils, platelet count, SII, and GGT. • The disability scores on admission, discharge, and peak were worse in the AIDP group. [ABSTRACT FROM AUTHOR]