A rare case of CD1a-negative Langerhans cell histiocytosis of the central nervous system in a child.

Langerhans cell histiocytosis is a dendritic cell disorder with a wide spectrum of severity and presentations. Histopathology typically demonstrates a proliferation of Langerhans cells and a lymphohistiocytic inflammatory infiltrate with eosinophils. The diagnosis is supported by immunohistochemistry with the cell markers S100, CD1a, CD68, and Langerin [, 126, 2015, 26 and , 331, 1994, 154].