RESUMO
Acanthosis nigricans (AN) is characterized by velvety hyperpigmented plaques, usually observed in skin folds. The different types of the condition include obesity-associated, syndromic, drug-induced, malignancy-related, and other types of AN. AN, an FGFR3 gene mutation-related disease, is associated with varying degrees of skeletal disorders. FGFR3 gene mutations are known to cause excessive inhibition of chondrocyte growth and keratinocyte proliferation, which is responsible for AN development. To our knowledge, only a small number of cases of AN with hypochondroplasia due to FGFR3 gene mutation (p.Lys650Thr) have been described in the literature. However, there are no reports of genetically confirmed AN with hypochondroplasia in Korea. Physicians should consider syndromic AN when symptoms develop at an early age or when associated skeletal anomalies are present.
RESUMO
Background@#Juvenile dermatomyositis (JDM) is a rare but common childhood idiopathic inflammatory myopathy. Proximal muscle weakness and pathognomonic skin rash, Gottron papules, and heliotrope rash are characteristic clinical features of JDM. However, clinical analysis of JDM has rarely been reported in the Korean dermatologic literature. @*Objective@#This study aimed to investigate the clinical features and outcomes of JDM in Korea and previous studies. @*Methods@#We retrospectively reviewed the medical records and clinical photographs of patients diagnosed with JDM at Pusan National University Hospital (Busan and Yangsan) for 17 years (2005∼2021). @*Results@#We encountered 12 patients with JDM (male to female ratio=7:5) with a mean age of 7.2 years. The most common clinical features were Gottron papules (100%), followed by Gottron sign (83.3%), malar rash (58.3%), heliotrope rash (41.7%), shawl sign (16.7%), calcinosis cutis (8.3%), and ulcer (8.3%). In all cases, there was no concurrent interstitial lung disease or an underlying malignancy. Only 1 of 12 patients complained of proximal muscle weakness, and four patients showed an increase in muscle enzymes in the laboratory test. The skin lesions gradually improved after systemic steroid or topical treatment in all cases. No additional proximal muscle weakness was found during the follow-up. @*Conclusion@#Although proximal muscle weakness is a common symptom in JDM, clinically amyopathic JDM is commonly found in dermatologic clinics. Regardless of subtype, all patients responded well to treatment and rarely encountered recurrence.