Genetic basis of Darier-White disease: bad pumps cause bumps

Severe Darier's disease in a psychiatric patient

Darier's disease is characterized by dense keratotic lesions in the seborrheic areas of the body such as scalp, forehead, nasolabial folds, trunk and inguinal region. It is a rare genodermatosis, an autosomal dominant inherited disease that may be associated with neuropsichiatric disorders. It is caused by ATPA2 gene mutation, presenting cutaneous and dermatologic expressions. Psychiatric symptoms are depression, suicidal attempts, and bipolar affective disorder. We report a case of Darier's disease in a 48-year-old female patient presenting severe cutaneous and psychiatric manifestations.

Dyskeratosis follicularis disease: case reports and review of the literature

BACKGROUND

Dyskeratosis follicularis (Darier's disease) is rare autosomal dominant disease characterized by the loss of adhesion between epidermal cells and by abnormal keratinization.

METHODS

We performed a retrospective study of all the patients diagnosed with Darier's disease at the Department of Dermatology of Charles Nicolle Hospital of Tunis, between 1971 and 2002.

RESULTS

During the observation period, we identified 12 patients with Darier's disease; five males and seven females with a mean age of 17.36 years. No family history was found in eight patients. Skin lesions in the form of keratotic papules were noted in seborrhoeic areas, essentially the face (nine patients), chest and scalp. Seven patients had nail lesions. UV light exposure exacerbated the disease symptoms in seven cases. The patients were treated with topical and systemic retinoids (six cases).

CONCLUSION

Although Darier's disease has a chronic course, most patients manage to lead a relatively normal life. Treatment is usually unsatisfactory despite much progress in understanding of the underlying abnormalities in Darier's disease.

Origin of the epidermal calcium gradient: regulation by barrier status and role of active vs passive mechanisms

Mammalian epidermis displays a characteristic calcium gradient, with low calcium levels in the lower, basal, and spinous epidermal layers, whereas calcium levels increase progressively towards the outer stratum granulosum, and declining again in the stratum corneum. As the calcium gradient disappears after acute permeability barrier disruption, and returns after 6 h in parallel with barrier recovery, barrier function (through restriction of transcutaneous water movement) could regulate the formation of the epidermal calcium gradient. Two types of experiments confirmed the role of barrier status in regulating the calcium gradient: (i) either a vapor-permeable membrane (Gore-Tex) or an emollient (Vaseline), applied after acute barrier disruption, immediately restored barrier function, while accelerating the return of the calcium gradient, and (ii) in contrast, applications of lovastatin, a cholesterol synthesis inhibitor, which delayed barrier recovery and retarded the return of the calcium gradient. We next asked whether the calcium gradient is formed/maintained by passive and/or active mechanisms. Previous studies have demonstrated that cold exposure (4 degrees C) blocks permeability barrier recovery after acute disruption. Here, we abrogated the barrier with tape-stripping, and then compared barrier recovery and restoration of the calcium gradient in hairless mice exposed to 4 degrees C external temperatures, with and without occlusion with Gore-Tex. Although low levels of returned calcium throughout the epidermis, acutely disrupted, unoccluded, cold-exposed sites showed neither barrier recovery nor reappearance of the calcium gradient at 5 h. In contrast, acutely disrupted, cold-exposed sites, covered with Gore-Tex, likewise displayed little barrier recovery, but the calcium gradient largely returned by 3 h. These results show that (i) barrier status regulates formation of the calcium gradient, and (ii) passive processes alone can account for the formation/maintenance of the calcium gradient.