Clubbed nails is defined as an increased curvature of the nail plate which may be due to a wide variety of reasons. In this patient, the large, convex nails are a hereditary anomaly and were found to be present in both father and brother. Other causes of clubbing of the nails in children include cyanotic congenital heart disease, cystic fibrosis, and chronic inflammatory bowel disease.
Color Atlas of Pediatric Dermatology
Samuel Weinberg, Neil S. Prose, Leonard Kristal
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