Darier’s disease (keratosis follicularis) is a autosomal dominant genodermatosis
-It’s mutations affects ATP2A2 which codes for a calcium pump located on the membrane of the endoplasmic reticulum (an intracellular organelle)
-The dysfunctional calcium pump results in the clinical presentation of this keratinization disorder: keratotic papules which have a greasy appearance and which give to the skin a dirty look.
-Treatment is unsatisfactory and consists of topicals and oral isotretinoin – but both are limited as irritation reactions often develop
In this Swedish study IQ data was collected in a retrospective analysis from the National Patient register. (inpatients from 1973 and outpatients since 2001)
-This amounted to 770 patients with Darier’s disease
-This was compared with 10 individuals from the general population (matched for age, sex, and location) chosen at random from the registry (7700 individuals)
Results show that:
-in individuals with Darier’s disease, intellectual disability was found in 13 individuals (1.69%) [757 were normal (98.31%)]
-in the general population group, intellectual disability was found in 21 individuals (0.27%). 7679 wer normal (99.73%]
-All in all, Darier’s disease carried a 6.2 risk ratio compared with the general population of developing cognitive impairement.
To conclude, this study shows that central nervous system involvement in Darier’s disease can be present in addition to the skin lesions.
This reminds us of the close relationship existing between the skin and the nervous system.
Indeed during embryogenesis, the ectoderm, gives rise to the epidermis of the skin and the neurectoderm**, which will develop into the nervous system.*
Comment: Intellectual disability can be present in Darier’s disease. According to the study, 1.5% of individuals have intellectual disability (around 6 times more than healthy individuals)