The Diagnostic Accuracy of Dermoscopy for Scabies

BACKGROUND: Scabies is a contagious skin infestation characterized clinically by nocturnal pruritus, visible burrows and contagiousness. Dermoscopy has been suggested as an alternative for diagnosing scabies. But, there have been few well-designed studies evaluating the diagnostic accuracy of dermoscopy. OBJECTIVE: We tried to confirm the diagnostic accuracy of dermoscopy for diagnosing scabies. We also tried to demonstrate specific circumstances in which dermoscopic identification of mites ("with dermoscopy") is more useful in diagnosing scabies, and to identify the specific clinical findings that could be used as a possible marker in diagnosing scabies. METHODS: We compared the scraping procedure "with dermoscopy" and "without it" in 49 patients, measuring the duration and outcome of each procedure. Also, we tried to find the specific clinical factors associated with our objects. RESULTS: The skin scraping "with dermoscopy" was superior to "without it" with respect to the duration and accuracy of the procedure. A history of previous steroid treatment was associated with the superiority of dermoscopy. The correlation between the presence of visible burrows and the positive outcomes of "with dermoscopy" was statistically significant. CONCLUSION: Skin scraping with dermoscopy is implicated as the diagnostic method of choice for scabies at the present time. Dermoscopy is especially useful in diagnosis of incognito scabies. In addition, the presence of visible burrows could be a reliable positive marker of scabies in the absence of dermoscopy or microscopy data.