Visual hallucinations and HLA class II antigens in cortical dementia.

BACKGROUND

Visual hallucinations are a core feature of dementia with Lewy bodies (DLB) and have been proposed as being part of a narcolepsy-like REM sleep disorder. Selective loss of hypothalamic hypocretin-producing neurons is common to both narcolepsy and the spectrum of Lewy body diseases. We hypothesized that the genetic marker associated with narcolepsy, the HLA class II DR2-DQ6 haplotype, could confer some degree of susceptibility to brainstem-hypothalamic damage leading to the manifestation of visual hallucinations.

METHODS

We examined HLA class II haplotypes in 30 patients with prominent visual hallucinations in the context of clinical criteria for DLB and in 30 patients affected by a cortical-type dementia without hallucinations.

RESULTS

No significant differences were found in the distribution of DR and DQ antigens.

CONCLUSIONS

We conclude that hypothalamic vulnerability in different diseases is not mediated by a common HLA haplotype.