Schamberg's disease, which was first described in 1901, is a relatively rare human skin disease. Another name for it is progressive pigmented purpuric dermatitis, which is something of a mouthful. Found more in males than in females it is caused by leaky blood vessels and leads to discolouration of the skin and is especially commonly found on the legs.
Schamberg's disease typically spreads around the body slowly but it is a chronic disease and may begin in childhood. It is a form of dermatitis. This is a general term for any problem that involves inflammation of the skin, including everything from eczema to psoriasis. It is also related to a number of other diseases that result in pigmentary purpuric eruptions such as Majocchi's disease, Gougerot-Blum syndrome, Ducas and Kapetanakis pigmented purpura, and lichen aureus.
The underlying cause of Schamberg's disease is not known at present. There are a number of suggestions though. These range from viral infection, hypersensitivity to some stimulus, immune system related problems, and a reaction to some form of medication such as thiamine or aspirin, for example.
Mechanically, the cause is when the blood vessels begin to leak. This allows red blood cells, the most common blood cell type and responsible for transporting oxygen around the body, to escape. These cells are filled with iron, which is used in the transporting of oxygen. When the red blood cells escape from the blood vessel and fall apart the iron is released into the outlying tissue. This causes a rusty coloured tint to be perceived in the skin at the point of the breakage.
So the lesions that appear as a result of these blood vessel breakages are the main symptom of the disease. They could appear anywhere on the body but are most likely to appear on the lower limbs. Spots like cayenne pepper appear around the sites of lesions. This can last for a number of years potentially. Another symptom that may be present is itching at the site of the breakage. Patients are often asymptomatic though.
Schamberg's disease currently has no permanent cure. If itching is present as a symptom then this can be diminished by cortisone cream. This is a steroid hormone that can be used to suppress a normal immune response to a variety of symptoms of diseases where this is a desirable thing to do. The itching could also be treated with antihistamines.