Yoko Mikami-Terao

Lymphocytic hypophysitis with central diabetes insipidus and subsequent hypopituitarism masking a suprasellar germinoma in a 13-year-old girl Abstract Case report: We report a case of central diabetes insipidus, hypothyroidism, and subsequent hy-popituitarism due to lymphocytic hy-pophysitis masking a germinoma in a 13-year-old pubertal girl. Magnetic resonance revealed an enlarged pitu-itary gland and a mass lesion in the pituitary stalk and inferior hypothala-mus. Open cranial surgery of the anterior pituitary showed active hy-pophysitis with lymphocytic infil-trates but without necrosis. Despite prednisolone therapy, 1 year later an enlarged, irregular cystic mass lesion had developed; in the pituitary stalk and inferior hypothalamus, a endo-scopic biopsy revealed germinoma. Conclusion: Lymphocytic hypophy-sitis in children may be the first sign of a host reaction to an occult germi-noma. The diagnosis of central diabetes insipidus with a thickened pituitary stalk requires long-term follow-up to establish the underlying cause