Successful treatment with 2-chlorodeoxyadenosine of refractory pediatric Langerhans cell histiocytosis with initial involvement of the gastrointestinal tract.

Gastrointestinal (GI) tract involvement in Langerhans cell histiocytosis (LCH) is extremely rare. Langerhans cell histiocytosis with GI tract involvement (GI-LCH) is frequently associated with multi-system disease, and usually presents with severe systemic symptoms, such as protein-losing enteropathy (PLE). Although the GI tract is not included among the organs at risk, the prognosis of GI-LCH is poor, and no effective chemotherapeutic regimen has been identified. Here, we report an infant case of primary refractory GI-LCH with PLE that showed marked improvement in response to 2-chlorodeoxyadenosine (2-CdA) therapy with no severe adverse events, even under conditions of deteriorating general health. The present findings indicate that 2-CdA may be effective for refractory GI-LCH with PLE. Further studies are warranted to determine the optimal therapeutic strategies for GI-LCH with PLE.