Sinus histiocytosis with massive lymphadenopathy (SHML) prednisone resistant but dexamethasone sensitive

Sinus histiocytosis with massive lymphadenopathy (SHML) is a histiocytic disorder affecting children and adults. It usually presents as markedly enlarged lymph nodes that require surgical biopsy for confirmation. This lesion is usually self-limited but can present in areas that can cause significant morbidity or disfigurement. We report a case that required therapy due to the severe disfigurement but was resistant till treated with dexamethasone. This case illustrates that SHML may be resistant to prednisone but still be sensitive to dexamethasone.