A 66-year-old woman presented with intense generalized itching after a trip abroad. Physical examination and manual dermoscopy confirmed the presence of multiple mite burrows (fig. 1) followed by a symmetrical papular eruption on the trunk and thighs. Subsequently, using a 365nm ultraviolet (UV) lamp, bright white-bluish structures corresponding to different parts of the mite burrow were seen, which supported the diagnosis of scabies (fig. 2).
The mite burrow is a well-known pathognomonic sign of scabies for dermatologists. Until now, visualization of the mite via optical microscopy, a technique known as Müller's test, is the diagnostic method of choice. However, this technique requires contact with the patient, training, and specific material to be performed. The 365nm UV LED light emits a white-bluish luminescence that is visible to the naked eye. When applied to the skin a bright white-bluish tunnel and a luminescent point corresponding to the mite's body can be seen. This technique seems to offer a new tool for diagnosing infestation by Sarcoptes scabiei and derivatives. Compared with Müller's test, this quick technique does not require direct contact, but a specific lamp.
