Prolidase deficiency in two dermatological patients in western Sicily.

Prolidase deficiency is a rare disorder inherited through an autosomal recessive gene. The hallmark of the disorder are iminodipeptiduria, chronic skin ulcers, recurring infections, mental retardation and characteristic facial appearance, although prolidase deficiency can occur with no clinical manifestation. The primary biological function of the enzyme involves the metabolism of collagen degradation products and the recycling of proline for collagen resynthesis. We describe two patients with prolidase deficiency and review the different clinical manifestations suggesting the pathogenetic mechanism through few hypotheses.

A pigmented papule acting like a playful ghost: dermoscopy of three targetoid hemosiderotic hemangiomas.

Targetoid hemosiderotic hemangioma represents an uncommon, distinctive, benign lympho-vascular lesion, with a variable clinical appearance, typically occurs in the lower limbs and trunk. Most patients are in their 20's or 30's. We describe three dermoscopic cases followed by the review of the literature. Dermoscopic images have been collected and have been evaluated for the presence of dermoscopic features. Concerning the review, we researched on pubmed and records were reviewed noting patient age of onset, sex, location, overall size, dermoscopic appearance. The harmonic mean age of patients was 31 years; the female-to-male ratio was 1:1, and the most common locations were lower extremities (47%) and the trunk (29%). In the most recent years several pediatric cases were described, lowering the mean age of the patients in the literature. Most targetoid hemosiderotic hemangioma appear clinically as a small, solitary, reddish-violaceous vascular lesion with a targetoid appearance. The most typical dermoscopic findings are a homogeneous central area, red lacunae, dark lacunae, peripheric red-violaceous ring, whitish structures, peripheric vascular structures, yellowish intermediate areas, and a peripheral pigment network. Histologically, more superficially, in the papillary dermis there are dilated thin blood vessels lined by hobnail-appearing endothelial cells. In the deeper dermis there are typically slit-like capillaries that ramify in the dermis and dissect through collagen bundles. We wanted to evaluate the features of a large series of targetoid hemosiderotic hemangiomas for a better awareness of the entity, to improve its clinical and dermoscopic diagnostic accuracy, to focus attention on nontargetoid patterns, which often mimic other lesions, including melanoma.

Plexiform Atypical Spitz Tumor With Rosette-Like Giant Cells: A Histologic and Immunohistochemical Study on a Case Suggesting Ganglioneuroblastic Differentiation: Review of the Literature and Considerations on Histogenesis.

Spitz nevi, atypical Spitz tumors and Spitzoid melanoma, the three clinicopathologic forms that constitute the spectrum of the Spitz-type melanocytic lesions, share a histologic picture characterized by large spindle and/or epithelioid ganglion-like cells, with various admixtures of multinucleate bizarre cells. This remarkable cytology has always been interpreted as an unusual, as well as unexplained form of atypia. We report a case of atypical Spitz tumor with Homer Wright-like rosettes, a feature characteristic of ganglioneuroblastic proliferation. Furthermore, the ganglion-like cells of the tumor showed basophilic punctuation in the cytoplasm, reminiscent of Nissl substance, and a few cells, whether spindled or epithelioid, were positive to neuron-specific enolase and glial fibrillary acid protein. Based on our findings, we hypothesize that the outstanding similarity of the ganglion-like cells of Spitz tumors to the normal parasympathetic ganglion cells and to the cells of ganglioneuroma and ganglioneuroblastoma may not be fortuitous. Instead, it may represent the expression of a specific pattern of melanocytic differentiation, analogous to the neurotization of common and cellular blue nevi, although in this case, it would privilege the parasympathetic lineage over the Schwannian, perineural, or endoneural pathway. Our hypothesis is supported by the literature reports of rosette formation and frank ganglioneuroblastic differentiation in Spitz tumors and melanoma and by the demonstration that parasympathetic neurons take origin from the same tracts of the neural crest as other neural and melanocytic cells.

Vitiligo susceptibility and catalase gene polymorphisms in Sicilian population.

BACKGROUND: Catalase gene (CAT) polymorphisms were analyzed as responsible for the deficiency of catalase enzyme activity and concomitant accumulation of excessive hydrogen peroxide in vitiligo patients. Catalase is a well-known oxidative stress regulator that could play an important role in the pathogenesis of vitiligo. This study was conducted to evaluate three CAT gene polymorphisms (-89A/T, 389C/T, 419C/T) and their association with vitiligo susceptibility in Sicilian population. METHODS: Sixty out of 73 Sicilian patients with vitiligo were enrolled and submitted to CAT gene analysis. RESULTS: Contrary to the Northern part of Europe but likewise to the Mediterranean area, the frequency of the CAT genotypes in Sicily is equally distributed. Out of all CAT genotypes, only CAT-89 T/T frequency was found to be significantly higher amongst vitiligo patients than controls. CONCLUSIONS: Despite the involvement of the CAT enzyme in the pathogenesis of vitiligo, the biological significance of CAT gene polymorphisms is still controversial. With the only exception for CAT variant -89A/T, the other studied CAT gene polymorphisms (389C/T and 419C/T) might not to be associated with vitiligo in Sicilian population.