Which condition is associated with a positive C-ANCA test?

Which condition is associated with a positive C-ANCA test?

• A. Granulomatosis with polyangiitis
• B. Churg-Strauss syndrome
• C. Polyarteritis nodosa
• D. Systemic lupus erythematosus

Answer: (A)

A positive C-ANCA (cytoplasmic anti-neutrophil cytoplasmic antibodies) test is primarily associated with Granulomatosis with polyangiitis (GPA), previously known as Wegener's granulomatosis. This autoimmune condition is characterized by the inflammation of blood vessels and often affects the respiratory tract and kidneys. The presence of C-ANCA is significant because it specifically indicates the involvement of antibodies against myeloperoxidase in neutrophils, which is a hallmark of GPA. In terms of pathophysiology, these antibodies play a crucial role in the development of the disease, as they are involved in the immune response that leads to vasculitis. The detection of C-ANCA is thus not only a diagnostic tool but also aids in monitoring disease activity and treatment response. Other conditions mentioned, such as Churg-Strauss syndrome, polyarteritis nodosa, and systemic lupus erythematosus, may involve different types of ANCA or have distinct serological markers that do not include a positive C-ANCA. For instance, Churg-Strauss syndrome is usually associated with P-ANCA (perinuclear ANCA), while polyarteritis nodosa does

A positive C-ANCA (cytoplasmic anti-neutrophil cytoplasmic antibodies) test is primarily associated with Granulomatosis with polyangiitis (GPA), previously known as Wegener's granulomatosis. This autoimmune condition is characterized by the inflammation of blood vessels and often affects the respiratory tract and kidneys. The presence of C-ANCA is significant because it specifically indicates the involvement of antibodies against myeloperoxidase in neutrophils, which is a hallmark of GPA.

In terms of pathophysiology, these antibodies play a crucial role in the development of the disease, as they are involved in the immune response that leads to vasculitis. The detection of C-ANCA is thus not only a diagnostic tool but also aids in monitoring disease activity and treatment response.

Other conditions mentioned, such as Churg-Strauss syndrome, polyarteritis nodosa, and systemic lupus erythematosus, may involve different types of ANCA or have distinct serological markers that do not include a positive C-ANCA. For instance, Churg-Strauss syndrome is usually associated with P-ANCA (perinuclear ANCA), while polyarteritis nodosa does