You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Pathogenesis of all of the following is granulomatous, except and explain in detail?
Robbins clearly mentions that “microscopic polyangiitis is characterized by segmental fibrinoid necrosis of the media with focal transmural necrotizing lesions; granulomatous inflammation is absent”.