What you’ll see: Transverse white bands parallel to the lunula. These bands usually occur in pairs and extend all the way across the nail.
This nail disorder is uncommon, and is 1 of 3 forms of leukonychia caused by abnormalities in nail bed vascularization. (The other 2 forms—Terry’s nails and half-and-half nails—are described on page 513.)
- nephrotic syndrome,
- liver disease,
- malnutrition, and
- those who have undergone chemotherapy.
What you’ll see: Most of the nail plate is white, with a narrow pink distal band. All nails tend to be uniformly affected, with an appearance of ground glass.15 Terry’s nails have been found in 80% of patients with cirrhosis of the liver.15
What to suspect: One study found Terry’s nails in 25% of 512 consecutive hospital inpatients, with researchers linking the disorder with cirrhosis, chronic CHF, and adult-onset diabetes mellitus.16 On rare occasions, Terry’s nails have been reported in hemodialysis patients and renal transplant recipients.17 Terry’s nails have also been observed in HIV patients.4
What you’ll see: The proximal portion on the nail bed is white because of edema of the nail bed and capillary network; the distal portion is pink or reddish brown. The nail plate is unaffected.
What to suspect: This nail disorder has occurred in patients with renal disease associated with azotemia.18 Half-and-half nails have also been detected in hemodialysis patients, renal transplant recipients,17 and in HIV patients.4
What you’ll see: The lunula is red. In addition to the red lunula pictured here, there is also the absence of lunula and azure lunula.
What to suspect: Red lunula has been associated with alopecia areata, and collagen vascular disease. It has also occurred in patients on oral prednisone for rheumatoid arthritis. Red lunulae are seen in cardiac failure, COPD, cirrhosis, chronic urticaria, psoriasis, and carbon monoxide poisoning.19
Absence of lunula was the most common nail disorder in a group of hemodialysis patients (31.9%) and has also been reported in renal transplant recipients (17.1%).17 Azure lunula occurs in patients with Wilson disease. It has also occurred in argyria and in patients taking medications like 5-fluorouracil and azidothymidine.20
What you’ll see: Extravasations of blood from the longitudinally oriented vessels of the nail bed. These hemorrhages do not blanch. They form as a result of the nail plate-dermis structural relationship and tend to be seen in older patients.
What to suspect: While trauma is the most common cause, they may also occur with psoriasis and fungal infection.
Bacterial endocarditis is the most common systemic disease associated with splinter hemorrhages. These hemorrhages are more common in subacute, rather than acute, infection. Although splinter hemorrhages in subacute bacterial endocarditis have been described as proximally located,21 there are no sufficient data to confirm this—mainly because splinter lesions migrate distally as the nail grows.22
Splinter hemorrhages may also be associated with mitral stenosis, vasculitis, cirrhosis, trichinosis, scurvy, chronic glomerulonephritis, and Darier’s disease. However, due to the diverse and common causes of splinter hemorrhages, they cannot be used as an isolated sign of illness, except when they are accompanied by things like fever, Roth’s spots, Osler’s nodes, Janeway’s lesions, or a heart murmur, since any of the above would greatly increase their significance.
- Systemic disease typically affects more than 1 nail.5,23
- Fingernails usually provide more accurate information than toenails because clinical signs on toenails are often modified by trauma.23
- Fingernails grow at a rate of 0.1 mm/day and toenails grow at a rate of 0.03 mm/day.5,23 Thus, you can estimate the time at which an initial insult occurred by measuring the distance between the cuticle and the leading edge of any pigmentation change.
Dimitris Rigopoulos, assistant professor of dermatology, University of Athens Medical School, 5 Ionos Dragoumi Street, 16121 Athens, Greece; firstname.lastname@example.org.