Picture of Clubbed Nails
Clubbed nails are an exaggerated downward curvature of the nails that may be indicative of systemic disease. Clubbing may occur in cases of cirrhosis, cystic fibrosis, inflammatory bowel disease, congenital heart disease, and other conditions. Some cases of clubbed nails are hereditary.
Text Reference: "Nail Abnormalities: Clues to Systemic Disease." American Family Physician.