Disease Assessment in Systemic Vasculitis

Raashid Ahmed Luqmani


Nephrol Dial Transplant. 2015;30(s1):i76-i82. 

In This Article

Predictive Value of Assessment Tools

Patients and doctors want to know the prognosis of having a diagnosis of vasculitis. In clinical trials it is useful to know whether a patient has a good or a bad prognosis to measure the effects of therapy to be able to stratify individuals with a worse prognosis to receive more aggressive therapy than those with a better prognosis. The Five Factor Score (FFS)[34–36] has been validated in patients with small and medium vessel vasculitis (originally for polyarteritis nodosa and eosinophilic granulomatosis with polyangiitis, but more recently also for granulomatosis with polyangiitis and microscopic polyangiitis), based on the extent of organ involvement.

The FFS includes items present at baseline which influence the risk of mortality. Any patient with at least one of the five factors has a much higher risk of dying than patients who have no risk factors. The original FFS included the following items: colon, renal impairment, proteinuria, gastrointestinal (GI) disease, cardiac involvement and central nervous system (CNS) involvement. It has been used in trials to stratify on the basis of disease severity: patients who either have at least one FFS or no factors have been randomized to either receive cyclophosphamide in addition to steroids, or steroids alone.

The current version of FFS[36] includes four positive factors: age (above 65), CNS involvement, cardiac involvement and renal involvement (which worsen the prognosis); and one negative factor: ENT involvement (which improves the prognosis).

BVAS also provides prognostic information and is effective in a number of studies in vasculitis: high BVAS at diagnosis predicts poor subsequent outcome in terms of mortality, but it also predicts responsiveness to therapy.[37,38] However, poor outcome is also affected by age and baseline renal function.[1]

The damage index, VDI, is probably the most accurate predictor for outcome that we currently have. Patients with more than five items on the VDI scale by 6 months after diagnosis have a subsequent risk of death of 17:1 compared with patients with five or less items on the VDI. This is even higher when critical items are involved, such as those in the cardiovascular or neurological system.[39]

Understandably, patients who accumulate more damage rapidly are more likely to die. Patients with poor baseline renal function (creatinine >200 µmol/L) have a reduced risk of future flare, with a sub-hazard ratio of 0.39 (95% confidence interval: 0.22–0.69).[2] Gene expression of the interleukin-7 receptor (IL-7R) pathway and T-cell receptor (TCR) signalling in memory T cells from patients with active or inactive vasculitis has been useful in predicting future relapse,[40] independent of the current state of activity.