A rare case of autoimmune hypophysitis presenting as temperature dysregulation.

Autoimmune hypophysitis is a rare cause of pan-hypopituitarism. Hypothalamic involvement in autoimmune hypophysitis is rare and usually manifests as central diabetes insipidus due to antibodies against arginine vasopressin. Temperature dysregulation is occasionally seen with suprasellar tumours but has never been reported with hypophysitis. We report a case of a middle aged man who presented to us with the complaints of documented body temperature fluctuations since two months followed gradually by hoarseness of voice, sexual dysfunction and syncope. Examination was remarkable for postural hypotension, dry coarse skin and delayed ankle reflexes. Patient's hormone profile revealed pan-hypopituitarism and elevated titre of anti-TPO antibodies. Patient's work up for secondary causes of hypopituitarism was negative. MRI brain revealed typical findings of hypophysitis. Patient was suspected as a case of autoimmune hypophysitis and was immediately treated with prednisolone along with hormone replacement. Rapid response within 30 days was observed in the form of subsidence of temperature fluctuations, improvement in general well being, sexual function and repeat MRI done after one month which revealed a partial empty sella. Autoimmune hypophysitis as a potentially treatable cause of temperature dysregulation has been highlighted in this case.