Definition
Subungual hemorrhage consists in the loss of blood just below the nail (the blood remains trapped between the lamina and the nail bed). The haematomas that are thus created are characterized by great pain and color of the nail from dark red to brown-black.
The causes are many. Most commonly, subungual hemorrhage is attributable to local trauma, but it can also be a sign of psoriasis, onychomycosis and eczema. In some cases, blood loss is made evident by red-brown thread-like lines running longitudinally with respect to the nail ("splinter" hemorrhages). This particular orientation is due to the longitudinal shape of the capillaries of the nail bed. "Splinter-like" hemorrhages are attributable to an increased capillary permeability.
In addition to trauma, potentially responsible causes include endocarditis and systemic diseases with skin involvement. "Splinter-type" bleeding may also be associated with renal, pulmonary and endocrine disorders.
Possible Causes * of Subungual Hemorrhage
- Cryoglobulinemia
- Dermatitis
- Infective endocarditis
- Onicofagia
- Onychomycosis
- Psoriasis
