tailieunhanh - Clinical Dermatology - part 4

Các tính năng chung bao gồm mệt mỏi và đau khớp. Khóa học quá trình viêm mạch khác nhau với nguyên nhân của nó, mức độ của nó, kích thước của mạch máu bị ảnh hưởng, và sự tham gia của các cơ quan khác. | 104 CHAPTER 8 Fig. Urticarial vasculitis a combination of urticaria and bruising. skin signs include angioedema. General features include malaise and arthralgia. Course The course of the vasculitis varies with its cause its extent the size of blood vessel affected and the involvement of other organs. Complications Vasculitis may simply be cutaneous alternatively it may be systemic and then other organs will be damaged including the kidney central nervous system gastrointestinal tract and lungs. Differential diagnosis Small vessel vasculitis has to be separated from other causes of purpura p. 145 such as abnormalities of the clotting system and sepsis with or without vasculitis . Vasculitic purpuras are raised palpable . Occasionally the vasculitis may look like urticaria if its purpuric element is not marked. Blanching such an urticarial papule with a glass slide may reveal subtle purpura. Investigations Investigations should be directed toward identifying the cause and detecting internal involvement. Questioning may indicate infections myalgias abdominal pain claudication mental confusion and mononeuritis may indicate systemic involvement. A physical exam- LEARNING POINT Leucocytoclastic vasculitis of the skin may indicate that the kidneys are being damaged. Be sure to check the urine. ination chest X-ray ESR and biochemical tests monitoring the function of various organs are indicated. However the most important test is urine analysis checking for proteinuria and haematuria because vasculitis can affect the kidney subtly and so lead to renal insufficiency. Skin biopsy will confirm the diagnosis of small vessel vasculitis. The finding of circulating immune complexes or a lowered level of total complement CH50 or C4 will implicate immune complexes as its cause. Tests for hepatitis virus cryoglobulins rheumatoid factor and antinuclear antibodies may also be needed. Direct immunofluorescence can be used to identify immune complexes in blood vessel walls but is .