Introduction: Infection and parasitic skin diseases in children are very common, and is a challenge of clinical diagnosis for details observation of the skin and sample-taken for microscopy. Dermoscopy has been widely used in the pigmented, neoplastic and inflammatory skin diseases. It has rarely been applied for infectious skin diseases for worry about the possibility of cross-infection by contacting each other. We used parafilm and disposable polyethene gloves to cover the front edge of dermoscope during contact with the lesion. Hence dermoscopy could be routinely used to observe the detailed lesion of the infectious skin diseases. In addition, ultraviolet (UV-dermoscopy) could more surprisingly unveil their mystery.
Diseases and Results: 1. Viruses infected skin diseases including molluscum contagiosum, verruca vulgaris, condyloma acuminatum, chickenpox, herpes zoster and simplex are easily diagnosed according to their special characteristics under dermoscopy. 2. Fungal infected diseases consist of tinea capitis, white piedra, tinea pedis, onychomycosis, tinea cruris, tinea corporis, pityriasis versicolor, Malassezia folliculitis, penicilliposis marneffei, sporotrichosis and chromoblastomycosis. 3. We observed all the life cycle stages of Phthirus pubis namely translucent empty nits, nits containing nymphs, nymph and adult phases within a single field view. The nits containing nymphs were brown and ovoid, the empty nits had flattened ends, and lice were seen grasping hairs with claws, inserting mouthparts into the skin, sucking the blood into their body. We used simple methods to enhance the diagnosis of scabies: ultraviolet dermoscopy demonstrated bright-white fluorescence and polarized dermoscopy after ink staining showed burrow, mite and its eggs were very clear. From a 44-year-old female presented with erythematous pruritic scales around the rosacea skin surface of nasolabial folds demonstrating follicular plugs by polarized dermoscopy. Demodex folliculorum was confirmed under light microscopy. Bright-pink, light-blue and light-green fluorescence under high-resolution UV light dermoscopy, indicated the metabolites of Propionibacterium acne, Malassezia yeasts and velvet hair respectively. Notably, a live Demodex folliculorum, was traced continuously crawling at time intervals respectively.
Conclusions: Parafilm and disposable polyethene glove are simple, easily available, cheap, and useful measures to maintain clean dermoscopy. We first described the cigarette-ash-shaped hair after effective antifungal treatment. UV-dermoscopy can also act as a mini and portable wood’s lamp device. UV light dermoscopy particularly investigates microbe and parasite without interfering the natural ecology of the skin surface. Dermoscopy is a convenient, quick and practical method for direct determination of pathogens, to investigate the clues of virus, fungi or parasites infection, and, to evaluate the efficacy of treatment, especially for the non-easy cooperation children