hemorrhagic spots on the skin
Introduction
Introduction Extensive or localized skin and submucosal hemorrhage, forming red or dark red spots on the skin and mucous membranes, about 3 to 5 mm in diameter or larger, and more than 5 mm is called ecchymosis.
Cause
Cause
(1) Extravascular factors: If the perivascular tissue is weak due to degeneration, atrophy and relaxation, it is prone to bleeding and form purpura. Extravascular factors are more common in senile or cachexia purpura. Capillaries and small blood vessels are slightly affected by a slight external force, which can cause rupture and hemorrhage.
(2) Vascular factors: refers to the purpura formed by the leakage of blood from the blood vessels to the outside of the blood vessels due to damage of the capillary wall. Purpura caused by vascular factors accounted for the first place in all purpura. After a small blood vessel injury in a normal person, the blood vessel immediately undergoes a reflex contraction, and the local blood flow is slowed down to promote hemostasis. If the peripheral blood vessels are brittle, the permeability is increased, and the vasomotor function is abnormal, it is easy to cause hemorrhagic purpura due to extravasation of blood from the blood vessels. The hemorrhage caused by vascular factors is characterized by capillary fragility test, but the bleeding time and clotting time are normal. The most common form of such purpura is allergic purpura. Second, bacterial or viral infections, vitamin C deficiency, chemical factors, etc. can cause damage to the blood vessel wall and cause purpura. In addition, there is an unclear increase in the brittleness of the blood vessel wall, which is common in women. The purpura can disappear on its own and has no adverse consequences. It is called simple purpura.
(3) Platelet factors: Platelets play an important role in the process of hemostasis. Thrombocytopenia or defects in platelet function may result in decreased or lost hemostasis, and are prone to purpura. Thrombocytopenia can be seen in idiopathic thrombocytopenia, secondary thrombocytopenia (also known as symptomatic purpura, thrombocytopenia due to bone marrow hematopoietic disorders, seen in aplastic anemia, leukemia, cancerous bone metastasis), radiation Substances and chemicals destroy megakaryocytes, which reduce platelet production and severe infections (such as typhoid fever, meningitis, sepsis) and excessive platelet destruction. In addition, etc. can also reduce thrombocytopenia. Platelet function-deficient diseases include hemorrhagic thrombocytosis and thrombocytopenia. Laboratory tests are important for the diagnosis of purpura caused by platelet factors, generally characterized by prolonged bleeding time, poor clot retraction and thrombocytopenia.
(4) Coagulation factor: Coagulation factor deficiency often causes coagulopathy and causes purpura. These diseases are rare, the causes are mostly congenital, and a few are acquired (mainly caused by liver disease). Patients with purpura should be examined for blood routine, platelet count, bleeding time, clotting time, capillary fragility test, skin and mucous membrane microcirculation, hemorheology and coagulation factors.
Examine
an examination
Related inspection
Allergen tester skin test immunopathological examination of urinary fibrin degradation products
Symptoms of purple spot disease: Purple spot disease is caused by skin bleeding, mainly in the hands and feet, mostly purple-red pea-sized spots (purple spots), and more lesions. The purple spot itself has no symptoms.
Hypersplenism, lupus erythematosus, uremia, etc. can also be caused.
Diagnosis
Differential diagnosis
Extensive or localized skin and submucosal hemorrhage, forming red or dark red spots on the skin and mucous membranes, about 3-5 mm in diameter or larger, and those who are not faded are called purpura. Usually, the diameter is less than 2 mm, which is called hemorrhage. If it is localized or fluctuated, it is hematoma.
Symptoms of purple spot disease: Purple spot disease is caused by skin bleeding, mainly in the hands and feet, mostly purple-red pea-sized spots (purple spots), and more lesions. The purple spot itself has no symptoms.
Hypersplenism, lupus erythematosus, uremia, etc. can also be caused.
