Skin rash with the histological absence of metachromatic granules as the presenting feature of Hunter syndrome in a 6-year-old boy.

摘要

Sir, A 6-year-old white boy presented to a dermatologist with a 3-month history of an asymptomatic papular eruption on his upper arms. The patient was the second child of nonconsanguineousparents and was born at 36 weeks gestation by Caesarian section due to breech presentation. For the first 4 weeks of life, he was diagnosed with hyaline membrane disease and was dependent on supplemental oxygen. The patient suffered from persistent wheezing and recurrent bronchiolitis until the age of 12 months, when his respiratory problems spontaneously resolved. For the past 2 years, he had had recurrent otitis media. There is some suspicion that the patient's maternal grandfather had a similar rash on the posterior aspect of his forearms. He had died of a malignancy in his mid-forties but otherwise had no known health issues.The rash consisted of asymptomatic, firm and ivorycolouredpapules which were distributed over the upper armsin a cobblestone pattern (Fig. 1a). A 3-mm punch biopsy of the rash revealed interstitial mucin deposition throughout the reticular dermis (Fig. 1b, c). There was no inflammation, or significantly increased fibroblast cellularity. Alcian blue stain at pH 2.5 and colloidal iron stains (with controls) highlighted the dermal mucin. The extent of the dermal mucinosis may have obscured cytoplasmic metachromic granules in dermal fibroblasts. Metachromatic granules were also not observed in eccrine glands or epidermal keratinocytes. A mucopolysaccharidosiswas suspected due to the characteristic appearance of the patient's rash and the dermal mucinosis.