Langerhans cell histiocytosis misdiagnosed as cow protein allergy: a case report

Background Langerhans cell histiocytosis (LCH) is a heterogeneous disease with diverse clinical manifestations. Abdominal organ involvement is rare. Early diagnosis and active treatment are needed. The purpose of this article is to enable readers to have a better knowledge of LCH and prevent misdiagnosis. Case presentation A 2-month-old boy had diarrhea, hematochezia, and a rash, and was diagnosed as having a cow milk protein allergy (CMPA). He was given an amino acid-based formula, but there was no sign of improvement in his condition. The patient then had a skin biopsy and was diagnosed as having multisystem Langerhans cell histiocytosis (MS-LCH). The general condition of the child deteriorated after the first two doses of chemotherapy, and the child died. Conclusions MS-LCH is a protracted and progressive condition with poor prognosis. Early diagnosis and treatment are essential for survival. If a child has chronic diarrhea and hematochezia in the presence of a characteristic rash, the pediatrician should consider the possibility of this disease to avoid misdiagnosis.