Surrogate parameters for vasculitis
| Organ involvement | Surrogate parameters |
| Glomerulonephritis | Proteinuria and haematuria with red blood cell casts |
| Arteritis | Angiographic or ultrasonic demonstration of aneurysms or stenoses in arteries provided the patient demonstrated other signs of vasculitis |
| Granulomatous inflammation in lower airways | Radiologically demonstrated pulmonary infiltrates or cavitations of more than one month's duration provided that all other causes such as infections and malignancies were ruled out |
| Granulomatous inflammation in upper airways | Bloody nasal discharge and/or crusting of more than one month's duration; chronic sinusitis, otitis and/or mastoiditis (proved by radiograph, CT or MRI); cranial bone and/or cartilage destruction; acute hearing loss, without signs of traumatic disease |