As C4d antibody is widely used for several indications in a routine surgical pathology laboratory, we aim to study C4d expression in the microvasculature of DM muscle biopsies, as a marker of complement activation. The role of C4d as a core diagnostic tool in the detection of antibody-mediated injury in renal allografts and other transplants has been established. C4d is now increasingly recognized as a potential biomarker where antibodies can cause tissue damage such as systemic autoimmune diseases. , Hence, identification of complement activation helps in diagnosing DM and in differentiating it from other IIMs.Ĭomplement split products have emerged as useful markers of antibody-mediated rejection in solid organ transplants.
#C4d complement mac
Therapies that intercept complement activation/assembly and deposition of MAC have shown beneficial effects in DM. , Both classical and alternate complement cascade members along with regulators are highly upregulated in DM patients. ,, , Detection of MAC was used as a diagnostic tool in the diagnosis of DM with high sensitivity and specificity. The earliest abnormality is formation and deposition of membrane attack complex (MAC) along with complement components on the endomysial blood vessels before structural changes take place or inflammatory infiltrates occur. The microangiopathy in DM is complement mediated. However, PFA is seen in only 50% of adults with DM when biopsied early in the course of the disease. DM is considered a microvasculopathy, characterized by injury to the capillary endothelium leading to depletion of capillaries in the muscle the damage to muscle is manifested as perifascicular atrophy (PFA) and is accompanied by inflammatory cell infiltrates. Early diagnosis and institution of adequate therapy are essential to alleviate muscle damage, improve muscle weakness and quality of life. It is also characterized by its association with interstitial lung disease, connective tissue disease (CTD), or malignancy.
#C4d complement skin
ĭermatomyositis (DM) differs from other IIMs by the characteristic skin rash and distinct histological and immunopathological features. The pathologic classification and identification of disease subgroups are extremely important for assessing treatment options and prognosis in individual patients. The idiopathic inflammatory myopathies (IIMs) are a heterogenous group of acquired muscle diseases which are potentially treatable. C4d as a marker of complement activation in dermatomyositis muscle tissue. How to cite this URL: Challa S, Uppin MS, Kannan MA, Rajasekhar L. How to cite this article: Challa S, Uppin MS, Kannan MA, Rajasekhar L. C4d can be used as a marker of complement activation and as an alternative marker to the membrane attack complex for the diagnosis of DM. C4d expression was seen in DM, corresponding to the capillary loss, and in the necrotic fibers, which indicates activation of the complement by the classical pathway. Key Message: Dermatomyositis (DM) is a complement mediated microangiopathy and early diagnosis facilitates therapies that intercept complement activation. Keywords: C4d, complement, dermatomyositis, muscle biopsy Results: C4d was expressed in all biopsies of definite dermatomyositis in the perimysial vessels and in 3/10 endomysial capillaries corresponding to capillary loss on CD 34.C4d expression was seen in 2/3 perimysial and endomysial vessels in nonspecific myositis (2/3 overlap myositis), and 1/1 of nectrotizing autoimmune myositis.Necrotic muscle fibers in all biopsies showed positivity irrespective of the diagnosis.Ĭonclusion: C4d can be used as a marker of complement activation for the diagnosis of dermatomyositis. Material and Methods: Muscle biopsies from patients diagnosed as definite dermatomyositis (10), nonspecific myositis associated with connective tissue disease (9), necrotizing autoimmune myositis (1), inclusion body myositis (1), and normal muscle (1) according to European Neuromuscular criteria 2004 were studied for C4d expression and capillary loss on CD 34 immunohistochemistry. Aim: To study C4d expression as a marker of complement activation in the diagnosis of dermatomyositis
0 kommentar(er)
