Relationship of type I procollagen to corticosteroid therapy in children with inflammatory bowel disease.

We determined the serum concentration of the C-terminal propeptide of type I procollagen (pColl-I-C) in 60 children and adolescents (ages 4 to 17 years) with inflammatory bowel disease (24 ulcerative colitis, 36 Crohn disease) and in seven children (ages 2 to 15 years) with nongastrointestinal disease (asthma) during varying regimens of corticosteroid therapy. Patients with inflammatory bowel disease were grouped according to disease severity (mild, and moderate to severe). Significantly lower pColl-I-C concentrations and growth velocities were found in each severity group among those subjects receiving daily corticosteroid therapy compared with those receiving alternate-day or no corticosteroid therapy (P less than 0.01). When daily corticosteroid therapy was initiated and then maintained for 7 to 14 days in 11 patients with exacerbation of inflammatory bowel disease clinical improvement resulted, but mean procollagen concentrations decreased significantly (P less than 0.001). In seven children with asthma receiving methylprednisolone intravenously, significant decreases in pColl-I-C concentrations were noted within 24 to 48 hours of therapy (P less than 0.001). These data indicate that serum procollagen values decrease during both short- and long-term daily administration of corticosteroid therapy. Longitudinal assessment of procollagen concentrations may provide rapid assessment of the effects of different corticosteroid regimens on growth.