There's a big purple patch on my thigh

There are many reasons for a large purple area on the thigh. It may be caused by accidentally bumping into something, resulting in subcutaneous bruising. If you use shower gel or handmade soap, or are allergic to the soap, it may also cause purple bruises on your legs. In addition, if there are unexplained bruises on the thigh, you should also consider the possibility of purpura or coagulation dysfunction. If the latter two situations occur, you need to go to the hospital for examination in time.

Purple bruises caused by subcutaneous blood congestion are not a serious problem and will generally turn black within three to five days. No special treatment is needed, it will be absorbed and dissipated slowly. Just don't irritate it to prevent secondary bleeding. Don't worry too much. If possible, check your blood routine to see if the platelet count is low.

As for purple bruises caused by allergies, you should pay more attention to food hygiene and try not to use shower gel, handmade soap, perfumed soap and the like. It is also best to avoid spicy and irritating foods, such as chili peppers, raw onions, raw garlic, etc. Eat more light foods, more vegetables and fruits to supplement vitamins. If necessary, you can go to the dermatology department of the hospital for examination.

Causes of purpura

(1) The cause of simple purpura is unclear. The disease is generally mild, with no obvious changes in the blood and blood vessels, and occasionally mild coagulation dysfunction.

(2) Henoch-Schonlein purpura often occurs due to increased permeability and fragility of the blood vessel walls. The vascular system becomes diseased, but the blood itself does not change. Therefore, laboratory tests such as platelet count, clotting time, and prothrombin time are all within normal range. It is a vascular allergic disease caused by the body's allergic reaction to certain allergens, which leads to increased capillary fragility and permeability, blood extravasation, bleeding in the skin, mucous membranes and certain organs, and other allergic manifestations.

(3) Idiopathic thrombocytopenic purpura: This disease is also known as hemorrhagic purpura and its cause is unknown. However, antiplatelet factors can be found in the blood of some patients. These factors can fight against platelets, causing a decrease in platelets and bleeding. It is a hemorrhagic disease characterized by immune destruction of platelets and thrombocytopenia in the circulating blood. It is characterized by extensive skin, mucous membrane and visceral bleeding, thrombocytopenia, normal or increased number of bone marrow megakaryocytes with maturation disorders, shortened platelet lifespan and positive antiplatelet antibody idiopathic thrombocytopenic purpura. It is more common in children and young adults, and more common in women than in men.

If you have purpura, you need to go to the hospital for examination and follow the doctor's instructions.

Causes of coagulation disorders

1: Hereditary coagulation dysfunction is generally a single coagulation factor deficiency, often with bleeding symptoms in infancy and often with a family history.

2. Acquired coagulation dysfunction is more common. Patients often have multiple coagulation factor deficiencies. It mostly occurs in adults. Clinically, in addition to bleeding, they are also accompanied by symptoms and signs of the primary disease.

1. Hemophilia

Hemophilia is the most common group of hereditary coagulation factor deficiency, which can be divided into two types: hemophilia A (deficiency of factor VIII, the procoagulant component of factor VIII) and hemophilia B (deficiency of factor IX). The biosynthetic genes of factor VIII:C and factor IX are both located on the X chromosome, so they are called X-linked diseases. Both are X-linked recessive inheritance, occurring in males and transmitted to females. Although female carriers have varying degrees of reduced factor VIII:C or factor IX activity, they generally have no bleeding symptoms. About 1/3 of patients have no family history. This may be because there are few males in the family or the disease is inherited from the previous generation and is overlooked, or it may be caused by gene mutation.

2. Von Willebrand Disease

Von Willebrand disease is an inherited bleeding disease whose clinical features are bleeding tendency since childhood, prolonged bleeding time and reduced platelet adhesion.