Serum YKL-40 as marker of articular manifestations in inflammatory bowel disease

ABSTRACT

Articular disease is a well-recognized manifestation of inflammatory bowel disease [IBD].A variety of joint disease patterns were described from oligo to polyarthritis or spondyloarthropathy. The aim of this study was to evaluate serum YKL-40 as a possible marker for articular disease in patients with IBD and to compare it with levels of CRP in these patients. This study included 38 patients suffering from IBD, including UC and CD. Patients with IBD were classified into two groups Group A included 20 patients without articular manifestations. While Group B included 18 patients with articular manifestations and were subdivided into 3 subgroups according to their articular pattern. Fifteen age and sex matched healthy controls were enrolled as Group C. All patients and controls were subjected to complete history taking with stress on presence of articular disease, full clinical examination, laboratory investigations including ESR, CRP [Avitex- Latex test] and Serum YKL-40 [MetraT YKL-40 EIA Kit]and radiological assessment. The distribution of articular disease in group B, type III [axial disease] was the commonest [61.1%], followed by type I [oligoarthritis] [22.2%] and lastly type II [polyarthritis] [16.7%]. Serum YKL-40 was the highest in group B, with significant difference when compared with group A and highly significant difference between both groups when compared with controls. While ESR and CRP showed non significant difference between groups A and B but significant difference was recognized when comparing both groups with control group. Also serum YKL-40 was the highest in type II subgroup of group B without any significant difference between the 3 subgroups. The latter observation was also found as regards results of CRP values in these subgroups, but type I was the highest. The mean number of affected joints [NAJs] in the 3 subgroups was the highest in type II without any significant difference between them. While a positive correlation was observed between [NAJs] and serum YKL-40 but no correlation was found between [NAJs] and CRP. SerumYKL-40 may be a useful laboratory marker in IBD which is able to predict the presence and perhaps the degree of joint disease regardless the influence of bowel inflammation. While CRP, although is a sensitive inflammatory marker lacks specificity to joint disease among these patients