Visual hallunications due to cardiac carcinoid

Mekuria S, Tan C, Schoenhagen P, et al. Shortness of breath and visual hallucinations. Am J Med 2009; 122: 338-341.

Patient had exertional dyspnea, night sweats, weight loss over six months. Week prior to admission, he developed visual hallucinations including ants crawling on wall and rabbits inside his room. ECHO showed a right heart cardiac tumor, eventually with an elevated urinary 5 HIAA. Brain imaging was negative. Authors postulated hallucinations were due to serotonin from tumor entering circulation, via a patent foramen ovale. Without a right to left shunt, the lung would have metabolized serotonin (adenosine deaminase). Octeotride resulted in less hallucinations, and effects were monitored with serotonin levels. Previous behavioral neurology of carcinoid syndrome includes behavior dysregulation (see Russo et al. Psychosoma Med 2003; 66:422-425).