Hereditary palmoplantar keratoderma type papulosa in Slovenia.

BACKGROUND Hereditary palmoplantar keratodermas (HPPK) are relatively frequent in Slovenia; however, the papulosa type of HPPK is rare. Epidemiological data are scarce; a population study in Croatia revealed a prevalence of 1.17/100,000 inhabitants. According to the preliminary data, it seems that HPPK papulosa is more common in Slovenia than in other countries. Efforts were made to identify all patients with HPPK papulosa in Slovenia. PATIENTS AND METHODS Existing hospital and outpatient records served as a starting point. Patients and their relatives were invited for examination. When necessary for preparing pedigrees, we visited patients. RESULTS Altogether 66 patients were observed, giving a prevalence of 3.3/100,000 inhabitants. 62 patients belonged to 11 unrelated families with two or more affected members and there were also four isolated cases. Our investigation points to an autosomal dominant mode of inheritance. All of the routine biochemical and hematologic tests were within normal limits. No malignancies were observed, nor were such data revealed in patients' histories. Thickened nail-plates were observed in three patients. CONCLUSIONS The prevalence of HPPK papulosa in Slovenia is higher than in other countries studied. Further loci mentioned in literature suggest a genetic heterogeneity in this condition.