Eun Ryoung Kim

Activating Mutation of GSα in McCune-Albright Syndrome Causes Skin Pigmentation by Tyrosinase Gene Activation on Affected Melanocytes

McCune-Albright syndrome (MAS) is a sporadic disease characterized by café-au-lait spots, polyostotic fibrous dysplasia and hyperfunctional endocrinopathies. To elucidate the mechanism of skin pigmentation, melanocytes, keratinocytes and fibroblasts were primary cultured from the café-au-lait spot of a MAS patient. Then, mutational analysis and morphologic evaluation were performed. Also, cAMP level and tyrosinase gene expression in cultured cells were determined. Only Gsα mutation was found in affected melanocytes and the cAMP level in affected melanocytes was higher than that of normal melanocytes. The mRNA expression of tyrosinase gene was increased in the affected melanocytes. This study suggests that skin pigmentation of MAS results from activating mutation of Gsα in melanocytes and the mechanism involves the c-AMP-mediated tyrosinase gene activation.

Masticator space abscess in a 47-day-old infant

A 47-day-old male infant presented with fever, poor oral intake, irritability, and right-sided bluish buccal swelling. Contrast-enhanced computed tomography of the neck showed a round mass lesion of about 2.0×1.5 cm that suggested abscess formation in the right masticator space. Ultrasound-guided extraoral aspiration of the abscess at the right masseter muscle was successful. Staphylococcus aureus was identified in the culture from the aspirated pus and blood. Appropriate antibiotics were given and the patient recovered. The patient underwent follow-up ultrasonography that showed an improved state of the previously observed right masseter muscle swelling at about 1 month after hospital discharge. A masticator space abscess usually originates from an odontogenic infection in adults. We report a case of masticator space abscess in a 47-day-old infant in whom septicemia without odontogenic infection was suspected.