There is bruise pain on the calf but no bruise

Many people have bruises on their calves for no apparent reason even though they have no injuries. This is an abnormal phenomenon and is also an obvious symptom of three diseases: simple purpura, allergic purpura, or thrombocytopenic purpura. These three diseases have both similarities and differences. Below, I will introduce the specific situation of these three diseases to you!

1. Simple purpura

It is a mild purpura seen in healthy people. It refers to a hemorrhagic disease in which purpura appears spontaneously and repeatedly on the skin, especially on the lower limbs, without any other symptoms and can disappear on its own without treatment.

It often occurs during the menstrual period in childhood and adolescent girls. Most of them have repeated bleeding spots or bruises on the skin of the lower limbs and buttocks. They are not raised on the skin surface and do not fade when pressed. After a few days or weeks, the purpura subsides and leaves blue or yellowish-brown pigmentation spots, which then gradually disappear. Skin purpura may reappear and occur repeatedly. Simple purpura is occasionally seen on both upper limbs but not on the trunk. Some patients experience local skin pain when purpura appears, which is generally not severe. Some patients may also be caused by autosomal dominant inheritance, which is more common in women with a positive family history, called familial simple purpura.

2. Allergic purpura

It is a capillary allergic disease. Purpura appears repeatedly, mostly on the lower limbs and buttocks, symmetrically distributed, and appears in batches. Purpura is higher than the skin and is often accompanied by allergic rash, joint pain or abdominal pain, fever, infection, and general discomfort. After the appearance of purpura, relevant examinations should be done, such as routine blood tests, platelets, platelet antibodies, clotting time, etc. After the cause is determined, active treatment should be given to the cause.

3. Thrombocytopenic purpura

Henoch-Schonlein purpura, also known as self-limiting acute hemorrhagic disease, is an allergic vasculitis that invades the small arteries and capillaries of the skin and other organs. The cause of the disease may be infection by pathogens, the effects of certain drugs, allergies, etc., which lead to the formation of IgA or IgG circulating immune complexes in the body, which are deposited in the capillaries in the upper dermis and cause vasculitis. The main manifestations are purpura, abdominal pain, joint pain and renal damage, but thrombocytopenia does not occur. Some people believe that allergic purpura and allergic cutaneous vasculitis belong to the same spectrum of diseases. This disease is the most common type of vasculitis in children. It is more common in school-age children, with the common age of onset being 7 to 14 years old. It is rare in infants under 1 year old.