The objective of this paper is to make a reflection about how the comorbidity of psychiatric and organic disorders can create several difficulties for the diagnostic and therapeutic approach of the both situations. The portuguese type of paramiloidosis disease was for the first time observed in 1939 by Corino de Andrade. In Portugal, the major focus of the disease, it presents a geographic distribution that must be known by the clinician. A thirty five's patient clinical case is described, who was hospitalized in the psychiatry hospital with the diagnosis of paranoid schizophrenia. After two months of hospitalization and four years after the beginning of the neurological symptoms, a complete organic study was developed, including gastroenterology and neurology evaluations. A diagnosis of Familial Amyloid Polyneuropathy (transthyretin-methionine 30 positive) was established, co - morbid with the diagnosis of paranoid schizophrenia. The authors conclued that the comorbidity with a mental disorder, in which delirious interpretation of the organic clinical situation was predominant in the clinical feature, and that took some time to be pharmacologically stabilized, associated with the fact that the patient hide that his mother and relatives of the mother side died because PAF, contributed significantly to the delay of the diagnosis. Beyond this, the clinical diagnosis of paranoid schizophrenia and the poor family and social background do not make him a potential candidate for a hepatic transplant. Influencing negatively the patient's coping, they can compromise the success of the transplant.