Background: Acanthosis nigricans (AN) is a dermatosis characterised by velvety hyperpigmentation, skin thickening, and papillomatosis. AN is generally associated with endocrine disorders (diabetes mellitus, obesity, polycystic ovary syndrome), drugs, and malignancy. In rare cases, it can be unrelated to any systemic disease. Here, we report on a 5-year-old boy from Turkey with diffuse, progressive skin hyperpigmentation.
Case report: He was born in a non-consanguineous marriage with normal growth and developmental milestones. Hyperpigmentation started at the age of 2 months, around the neck and axilla and spread to other body parts. The main complaint was the cosmetic appearance. He appeared well on physical examination. His blood pressure was within the normal range. Body weight (90 p) and height (90 p) were normal for the patients sex and age. Upon skin examination, velvety skin with hyperpigmentation and thickening were observed, especially involving periscrotal areas, armpits, neck, abdominal wall, and lumbar region. No change was detected in nails, teeth, and mucous membranes. Tests for the assessment of biochemical, hormonal, and haematological parameters showed no abnormalities. The test results for blood count, B12, thyroid hormones, insulin, C-peptide, HbA1C, cortisol, prolactin, total/free testosterone levels, IGF1, growth hormone, lipid profile, complete liver and renal function, and oral glucose tolerance were all within normal limits. Tumour markers were negative. Chest x-ray and abdominal ultrasound were normal. Skin biopsy was consistent with the diagnosis of AN, which revealed marked hyperkeratosis, acathosis, and papillomatosis.
Conclusion: Benign, generalised AN, in the absence of systemic disease in children, is rare. We found only nine case reports in literature. It is very important to exclude underlying causes of AN.
01 - 03 Oct 2015
European Society for Paediatric Endocrinology