The factitious disorder is characterized by simulation or exaggeration by the subject of his/her physical or psychological symptoms to take a sick role. This disorder may be associated with a real disease, used to simulate other symptoms and receive treatment. Our case is represented by a 49-year-old man, affected by Arnold Chiari Malformation Type I (ACM-I), a structural defect in the cerebellum with extension of the cerebellar tonsils into the foramen magnum, without involving the brain stem. The patient had three surgical operations involving the complete resolution of the disease. However, the subject reported a worsening of all symptoms, with the outcome of a severe self-limitation, with admission to a residential care and taken over by the multidisciplinary equipe of the district. Symptoms, which mainly consisted in pain, motor functional impairment, headaches, slurred speech were not evaluated due to the ACM-I. This diagnosis was confirmed when there was the complete resolution of the symptoms in a date pointed by the patient.

To make an appropriate differential diagnosis, in addition to the neurological examination, the subject had psychiatric interviews and completed an MMPI evaluation.

Neurological examinations revealed no residual outcome of the ACM-I. At MMPI there were not significant peaks. Regarding to the attitude towards this test and its validity, it appears an obvious attempt to lie from the patient, which tries to present himself in a favourable unrealistically way.

This case shows that appropriate diagnosis can help health services in a better management of their resources in such situations.

The authors have not supplied their declaration of competing interest.