Congenital leukonychia is a rare nail disorder that may occur in isolation or in association with a number of syndromic disorders. In the following letter, we describe a case of isolated congenital true leukonychia to add to the current literature. This case is particularly unique in that it does not appear to be inherited in an autosomal dominant fashion, in contrast to the majority of reported cases.

Pachydermoperiostosis, which occurs more frequently in men, is a rare entity with distinctive clinical features and an insidious onset.. We report the case of a 30-year-old man with a one-year history of acropachy, arthralgias, hiperhidrosis, and progressive skin thickening of the face and scalp.

The radiological findings were consistent with periostosis and the histopathological analysis from a facial skin biopsy showed a pandermal increase in the thickness and number of collagen bundles.

The pathogenesis of PDP is currently unknown, although an increased secretion of prostaglandin E2 (PGE2), which stimulates the overexpression of vascular endothelial growth factor (VEGF), has been suggested as a major factor. No specific treatment exists; however, in most cases, the disease tends to stabilize over time.