Table 3.
Feature | Evidence | PR3-AAV | MPO-AAV |
---|---|---|---|
Epidemiology | |||
♂/♀ ratio | B | Higher | Lower |
Geographical distribution | A | More prevalent in northwestern Europe and North America | More prevalent in southern Europe, Asia and the Pacific |
Incidence 11.3/million/yr in UK and 3/million/yr in Spain | Incidence 5.9/million/yr in UK and 7.9/million/yr in Spain | ||
Genetics | |||
HLA-DPB1 | A | More prevalent | Less prevalent |
HLA-DQ | B | Less prevalent | More prevalent |
PRTN3 | B | More prevalent | Less prevalent |
CTLA-4 | C | Less prevalent | More prevalent |
HLA-DRB*15 | C | More prevalent in African Americans | Not prevalent |
Renal histopathology | C | In both serotypes granuloma formation can be seen | |
Normal glomeruli | A | More | Less |
Fibrosis | C | Less | More |
Electron-dense deposits | D | Not different | |
Immunofluorescence | C | Less C3 deposition | More C3 deposition |
Clinical presentation | |||
Age at onset | A | Not different | |
Organ involvement in general | B | More ear, nose, and throat involvement | More renal-limited |
Pulmonary | C | Cavitating lesions | Fibrosing lesions |
Alveolar lung hemorrhage | C | More | Less |
Ear, nose, and throat | B | Necrotizing lesions | Polyps |
Nervous system | C | Similar frequency | |
Skin | C | Not different | |
Cardiac | C | Not different | |
Ophthalmologic | C | More ophthalmologic involvement | Less ophthalmologic involvement |
Follow-up | |||
Relapse rate | A | Higher | Lower |
Patient survival | C | Similar/better | Similar/worse |
Renal survival | C | Similar/better | Similar/worse |
Infection | D | Not different | |
Cardiovascular | C | Fewer events | More events |
Venous thromboembolism | D | Not different | |
Malignancies | D | Not different | |
Treatment | C | Not different | |
Etiology | C | S. aureusa | Silica associateda |
Low vitamin D levelsa | |||
Pathophysiology | |||
In vitro interaction of ANCA with neutrophils | D | Not different | |
Endothelial cells | D | PR3 induces apoptosis of endothelial cell | MPO induces production of intracellular oxidants |
Monocytes | D | PR3-ANCA induces release of sFlt1 by monocytes | MPO-ANCA does not induce release of sFlt1 |
In vivo animal models | D | Less successful models, possibly due to different interaction of PR3 with NB1 in mice | Successful mouse and rat models resulting in vasculitis and necrotizing crescentic GN |
Quality of evidence was based on the GRADE system as follows: A, Further research is very unlikely to change our confidence in the estimate of effect; B, Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate; C, Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate; D, Any estimate of effect is very uncertain). GRADE, Grading of Recommendations Assessment, Development and Evaluation.
These etiologic factors remain speculative due to insufficient evidence.