Lymphocytic Adenohypophysitis Associated with Rathke's Cleft Cyst

During the 8th month of her first pregnancy, a 40-year-old female suffered from visual disturbances. After treatment of pericarditis, which appeared 1 month after a normal delivery, she was referred to the neurosurgical department. She showed bitemporal hemianopsia, disturbance of visual acuity, and hypopituitarism. Initial computed tomography (CT) image showed a solid pituitary mass with suprasellar extension. However, 2 months later, the CT image changed to an enlarged partially cystic lesion. Transsphenoidal exploration of the sella demonstrated lymphocytic adenohypophysitis coexistent with Rathke's cleft cyst. To our knowledge, such an association has never been reported previously. Presurgical diagnosis of lymphocytic adenohypophysitis still remains difficult and surgical intervention is necessary for definitive diagnosis. However, special attention is needed for the histological diagnosis of this lesion, particularly in clinically atypical cases.