Rapid exacerbation of lymphocytic infundibuloneurohypophysitis.

Rationale: Lymphocytic hypophysitis is a relatively rare autoimmune disease defined by lymphocytic infiltration to the pituitary. Its rarity and wide spectrum of clinical manifestations make clarification of the pathology difficult. Here, we describe a case we examined from the primary diagnosis to final discharge, showing the serial progression of lymphocytic infundibuloneurohypophysitis (LINH) to panhypopituitarism with extrapituitary inflammatory invasion in a short period, and responding favorably to high-dose glucocorticoid treatment. Patient concerns: Polyuria, General fatigue and Nausea/Vomiting. Diagnoses: Central diabetes insipidus (CDI), Lymphocytic infundibuloneurohypophysitis (LINH). Interventions: Desmopressin acetate, High-dose glucocorticoid (GC) treatment. Outcomes: He was prescribed desmopressin acetate and subsequently discharged. A month later, he revisited our hospital with general fatigue and nausea/vomiting. A screening test disclosed hypopituitarism with adrenal insufficiency. MRI revealed expanded contrast enhancement to the peripheral extrapituitary lesion. He received high-dose GC treatment and the affected lesion exhibited marked improvement on MRI, along with the recovery of the anterior pituitary function. Lessons: This case demonstrates the potential for classical LINH to develop into panhypopituitarsim. We consider this is the first documentation of approaching the cause of atypical LINH with progressive clinical course from the pathological viewpoint.