Background: Antibodies against neutrophil cytoplasmatic antigens (ANCA) vasculitis is a complex group of small vessel inflammation were 2 type of antibody are detected: antimyeloperoxidase (MPO) and anti-peroxidase (PR3), although the mechanisms behind its activation is still not clear. Clinical picture of MPO- and respectively PR3-vasculitis is the same and only histological examination certify diagnose. Purpose: The present retrospective study done in Akershus University Hospital on a 9 years period, hypothesized that gender might play a role in type of ANCA antibody expressed and the clinical features of the patients diagnosed with ANCA vasculitis and kidney involvement. Method: A number of 754 were identified with ANCA positive blood test. Of those, 61 patients with kidney biopsy ANCA vasculitis were identified. 49 of them were new cases. Results: Results showed that the incidence rate was 9.1/million. The condition affects only adults, with a peak onset after age 50 years or above. The proportion of female expressed MPO was higher (58%), as well as the proportion of male expressed PR3 (60%). 35.4% of the patients from MPO group had severe kidney function at presentation compare to only 6.6% of the patients from PR3 group. Independent of type of antigen expressed, the females had more severe kidney function (stage iv and V), were more affected by breathing disturbances and weight loss, while males were more affected of stomach pains, nose bleeding and joint pains. Conclusion: The results suggest that gender might be linked with the expression of type of ANCA antibody and severity of kidney damage. But gender alone might influence the clinical features of these types of vasculitis independent of type of ANCA antibody (MPO or PR3).