To describe a rare case of Acromegaly presenting as psychotic disorder without neurological signs, in a 19 years old boy.

Single case report.

We describe the case of a 19 years old boy, that was taller than his peers and had started to grow his hands. He suddenly presented with an acute psychotic episode. He presented with persecutory delusions, perceptual abnormalities, disorganization and marked fluctuation in his behavior, he showed marked emotional liability, fluctuations in orientation and psychotic symptoms in the form of grandiosity, persecutory delusions and delusional misidentifications. At times, he was seen talking to himself, although he denied hearing any voices. There was no impairment of consciousness. His mood was irritable. An urgent CT and subsequent MRI scan revealed a pituitary macro adenoma, extending into the cavernous sinus. The initial diagnosis of prolactinoma was revised to acromegaly. His symptoms responded to combination of olanzapine and valproic acid, followed by trans sphenoid resection of the adenoma.

This case highlights the need for investigation, especially of neuroimaging, in atypical presentations of psychosis, which may be first manifestation of rare disorders like acromegaly. Despite a lack of information regarding the path physiology, this particular case emphasizes the importance of ruling out an organic cause for atypical presentation of psychosis.

The authors have not supplied their declaration of competing interest.