Castleman disease is a rare lymphoproliferative disorder of unclear etiology. It usually presents as localized enlarged lymph nodes in children. Surgical excision is curative in localized form. Clinical findings of malabsorption are rarely reported in the literature. Herein, we describe a 14-year-old girl who presented with anemia, failure to thrive, osteoporosis, zinc, and vitamin deficiency. She was diagnosed as localized mesenteric mixed type of Castleman disease. Her clinical findings improved after surgical excision of the mass.