Alpha-2 Glycoprotein in Serum as Noninvasive Biomarker of Inflammatory Bowel Diseases Severity in Children

Objective. The aim of the study is to evaluate diagnostic significance of human leucine-rich alpha-2 glycoprotein (LRG) for noninvasive diagnosis of inflammatory bowel disease (IBD) activity in children.

Methods. The study included 60 patients with IBD (Crohn’s disease — 33, ulcerative colitis — 27) who were examined in 2023–2025. The average age was 9.7 ± 4.9 years. Serum LRG levels were measured via enzyme-linked immunosorbent assay (ELISA), “sandwich method”, AssayPro kit, USA. Disease activity was evaluated with specific pediatric indices PUCAI and PCDAI. We have additionally analyzed several immunological markers (anti-Saccharomyces cerevisiae antibodies (ASCA), IgG, IgM, IgA), as well as standard clinical and laboratory parameters. All the data is presented as median, lower, and upper quartiles (Q1; Q3). We have used Kruskall – Wallis test for comparison of three or more groups, Dunn test with Holm correction for post hoc comparisons, Mann – Whitney U test for comparison of the two groups. The correlation between variables was estimated via Spearman’s rank correlation coefficient (ρ); differences at p < 0.05 were considered statistically significant.

Results. Serum LRG levels were statistically significantly higher in patients with high inflammatory activity compared to mild to moderate IBD activity according to PUCAI (p = 0.038) and PCDAI (p = 0.021) scales. The most profound differences were revealed when stratified by the degree of disease clinical activity. Statistically significant positive correlations were also mentioned between serum LRG levels and PUCAI (ρ = 0.556, p = 0.021) and PCDAI (ρ = 0.902, p = 0.001) activity indices, as well as with serum ASCA levels (ρ = 0.314, p = 0.039).

Conclusion. Serum LRG level is obviously an informative laboratory marker of IBD activity in children and can be recommended for implementation in comprehensive laboratory diagnostics and monitoring of therapy efficacy along with generally accepted indices and immunological indicators.

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