Nail finding	Associated systemic conditions
Shape or growth change
Clubbing	Inflammatory bowel disease, pulmonary malignancy, asbestosis, chronic bronchitis, COPD, cirrhosis, congenital heart disease, endocarditis, atrioventricular malformations, fistulas
Koilonychia	Iron deficiency anemia, hemochromatosis, Raynaud’s disease, SLE, trauma, nail-patella syndrome
Onycholysis	Psoriasis, infection, hyperthyroidism, sarcoidosis, trauma, amyloidosis, connective tissue disorders
Pitting	Psoriasis, Reiter’s syndrome, incontinentia pigmenti, alopecia areata
Beau’s lines	Any severe systemic illness that disrupts nail growth, Raynaud’s disease, pemphigus, trauma
Yellow nail	Lymphedema, pleural effusion, immunodeficiency, bronchiectasis, sinusitis, rheumatoid arthritis, nephrotic syndrome, thyroiditis, tuberculosis, Raynaud’s disease
Color change
Terry’s (white) nails	Hepatic failure, cirrhosis, diabetes mellitus, CHF, hyperthyroidism, malnutrition
Azure lunula	Hepatolenticular degeneration (Wilson’s disease), silver poisoning, quinacrine therapy
Half-and-half nails	Specific for renal failure
Muehrcke’s lines	Specific for hypoalbuminemia
Mees’ lines	Arsenic poisoning, Hodgkin’s disease, CHF, leprosy, malaria, chemotherapy, carbon monoxide poisoning, other systemic insults
Dark longitudinal streaks	Melanoma, benign nevus, chemical staining, normal variant in darkly pigmented people
Longitudinal striations	Alopecia areata, vitiligo, atopic dermatitis, psoriasis
Splinter hemorrhage	Subacute bacterial endocarditis, SLE, rheumatoid arthritis, antiphospholipid syndrome, peptic ulcer disease, malignancies, oral contraceptive use, pregnancy, psoriasis, trauma
Telangiectasia	Rheumatoid arthritis, SLE, dermatomyositis, scleroderma