ABSTRACT
Background: Collagenous duodenitis and gastritis are rare histopathological findings in children. Patients and methods: : We describe a four-year old girl, who presented with non-bloody diarrhea for two months and progressive edema with an albumin of 16g/dl. Results: The diagnosis of a protein losing enteropathy was made. Extensive investigations withheld only an infectious cause of the protein losing enteropathy (cytomegalovirus and adenovirus). However, the patients still required repetitive albumin infusions 3.5 months after onset of symptoms without spontaneous recovery. Therefore, a new endoscopic work-up was performed. Duodenal biopsies revealed collagen deposition, in association with a high number of eosinophils and mast cells throughout different parts of the gastrointestinal tract. Conclusions: The collagen deposition seems to be triggered by an eosinophilic gastrointestinal disorder. Treatment was started with amino acid-based formula, oral iron therapy, an antihistamine, and a proton pomp inhibitor that resulted in persistent normalization of serum albumin already after 1.5 weeks.