Collagenous inflammatory conditions are rare disorders characterized by a finding of increased subepithelial collagen deposition, typically with an associated inflammatory infiltrate, in the lamina propria of the stomach and intestines . Most pediatric cases in the literature have reported collagenous disease limited to the mucosa of the stomach with a generally benign prognosis. Involvement of the entire gastrointestinal tract, as described in this case report, is exceedingly rare and can be life-threatening.
A two-and-one-half-year-old previously healthy female presented with a ten-week history of watery diarrhea, nonbilious and nonbloody emesis, and low-grade fevers. She was found to have severe hypoalbuminemia and hypogammaglobulinemia. Her symptoms persisted, and she became dependent on parenteral nutrition. Biopsies obtained during subsequent endoscopic and colonoscopic studies revealed findings consistent with collagenous gastroenterocolitis. She responded to an empiric course of prednisone, but her symptoms recurred shortly after transitioning to oral budesonide. After successful reinduction with intravenous prednisone, intramuscular methotrexate was initiated. She remained asymptomatic during a 15-month course of therapy, and she continued to do well clinically until approximately nine months after weaning off methotrexate. At that point, she experienced a recurrence of diarrhea, and repeat endoscopic evaluation confirmed collagenous colitis. This responded nicely to a short course of oral budesonide, and she has since remained asymptomatic and off any therapy.
Conclusively, more studies are needed to understand the natural history of patients presenting with extensive collagenous mucosal inflammatory disease. In particular, there is a need to develop more standardized approaches to acute and chronic immunosuppressive therapy, including the use of steroid-sparing agents such as methotrexate.