The utility and challenges of histopathologic evaluation in the diagnosis of nonmalignant skin ulcers.

Histopathologic evaluation of cutaneous ulcers is indicated when the clinical diagnosis is unclear or when ulcers have not responded to standard of care. Many nonmalignant skin ulcers lack specific histologic findings on biopsy and pose a diagnostic challenge. While the usefulness of skin biopsies to diagnose underlying malignancy in ulcerated lesions has been demonstrated in previous studies, their utility in the diagnosis of ulcers of other etiologies has not been reported. We conducted a retrospective study of 45 nonmalignant ulcer biopsies in a 3-year period to compare the histologic diagnosis with the final diagnosis. Additionally, we assessed the diagnostic concordance among three blinded dermatopathologists when reviewing these cases. The leading histologic diagnosis from each of the three observers agreed with the final clinical diagnosis, on average, for 29.6% of the cases (average pairwise kappa = 0.15). Inflammatory ulcers had the lowest concordance between the observers and final diagnosis with an average of 26.0% of cases (average pairwise kappa = 0.06). The observers agreed with each other for 35.6% of the cases (Fleiss' kappa = 0.32). The highest agreement among observers was in the vascular/vasculopathic category (50%, Fleiss' kappa = 0.44). Our results indicate that skin biopsies alone are useful in the evaluation of nonmalignant ulcers to rule out other conditions (e.g. neoplasm) but frequently not sufficient to establish a definitive diagnosis. Additional clinicopathologic correlation is necessary in the final assessment of nonmalignant ulcers to determine the diagnosis. Future research endeavors should explore alternative approaches to more efficiently diagnose nonmalignant skin ulcers.

Antidesmoglein 1 and 3 antibodies in healthy subjects of a population in the Peruvian high amazon.

BACKGROUND: The objective of this study was to determine the presence of anti-Dsg1 and Dsg3 antibodies in healthy subjects of the high Peruvian Amazon (Tuemal, Rodriguez de Mendoza province, department of Amazonas) to establish the theoretical presence of environmental factors or triggers in the area. MATERIALS AND METHODS: Cross-sectional study. The study population included persons of any age or gender, clinically healthy, who were evaluated by a dermatologist to confirm the absence of blistering diseases. Blood samples were analyzed by indirect immunofluorescence (IIF), immunoprecipitation (IP), anti-Dsg1 IgM antibody (Ab) enzyme-linked immunosorbent assay (ELISA), as well as anti-Dsg1 and anti-Dsg3 IgG Ab ELISA. RESULTS: Participants included 21 healthy subjects comprised of 61.9% males and 38.1% females; 47.6% had a positive anti-Dsg1 Ab ELISA for total IgG (or any subclasses). IIF detected antibodies against intercellular spaces in one subject. Anti-Dsg1 Ab IP was mildly positive in 33.3% of the subjects. Anti-Dsg1 IgG subclasses found positive were: IgG1 (19.0%), IgG2 (33.3%), and IgG3 (28.6%); none of the samples were positive for anti-Dsg1 Ab IgM ELISA, and 23.8% of the subjects were positive for anti-Dsg3 Ab ELISA. The age distribution was similar for subjects positive for anti-Dsg1 and anti-Dsg3 Ab ELISA, with higher frequencies found among the 20-29 and 40-49 year-old age groups. CONCLUSION: A fraction of healthy subjects of the high Peruvian Amazon developed anti-Dsg1 and anti-Dsg3 antibodies, demonstrating the possible presence of environmental factors for endemic pemphigus (EP) at a higher altitude than previously described.