Charles Bonnet Syndrome: A Case Study

Abstract

The Charles Bonnet syndrome, whose aetiology and pathogenesis is still unknown, is characterised by the appearance of complex, persistent or repetitive hallucinations, partial or total insight into the hallucinatory phenomena, and an absence of delirium or of hallucinations of any other type. Classically, the syndrome has been described in elderly women who present concomitant visual alterations and cognitive defects. The images appear suddenly, with the eyes open, with no voluntary control and can last from seconds to days. We present the case of an adult male with Charles Bonnet syndrome, possibly secondary to an acquired cytomegalovirus retinitis in the context of an acquired immune deficiency syndrome (AIDS). The brain CT revealed cortico-subcortical cerebral atrophy. At present, there is controversy concerning the aetiology of this syndrome since it is commonly linked to the first stages of dementia. In addition, the clinical picture could be caused by undetectable effects of HIV on the brain. The visual hallucinations could be the result of persistent neuronal activity after the damage caused by the visual lesion. The latest findings have shown the presence of chronic brain damage, different underlying neurological diseases and a reduction in the perfusion of the left area of the occipital lobe in the majority of cases. The most frequently used drugs include carbamazepine and the neuroleptics. In our case, haloperidol, chlorpromazine and benzodiazepines were used and the clinical picture resolved completely within a few days.