Multidisciplinary approach to lupus nephritis: Clinical pearls, pitfalls, and positioning of newly-approved agents.

Lupus nephritis (LN) is a major course of morbidity and mortality in patients with systemic lupus erythematosus (SLE), best managed by a multidisciplinary group. To this end, we gathered a group of rheumatologists, nephrologists and a nephropathologist to review current evidence regarding diagnosis and management of LN. In this consensus paper, we summarize the key points from this meeting and provide practice guidelines for the management of kidney involvement in SLE, in view of emerging new data concerning novel agents approved recently. Renal biopsy is indispensable for the management of LN. Yet, important pearls and pitfalls need to be considered regarding indications and interpretation, which are summarized in informative tables. In new-onset LN, experts agreed that, although belimumab may be added from disease onset, patients with moderate to severe proliferative nephritis (defined as: NIH activity index > 5 plus ≥ 1 of the following: (i) NIH chronicity index > 2, (ii) proteinuria > 3  g /24 h, and (iii) increase in serum creatinine > 20%) may be more likely to benefit the most. In all other patients who have already started standard-of-care treatment with either mycophenolate mofetil (MMF) or cyclophosphamide (CY), belimumab could be considered in cases with an inadequate clinical response by 3 months, or in cases that experience a nephritic flare following initial response, or have an inability to reduce the dose of glucocorticoids. In all circumstances, the drug should be given as add-on therapy, that is, in combination with a standard-of-care therapy (MMF or CY). Voclosporin could be considered for up to 3 years, in combination with MMF, in patients with heavy proteinuria (well above the nephrotic range), wherein a quick reduction of protein loss in urine is desirable to avoid the complications of the nephrotic syndrome, either as part of the initial regimen, or in cases of inadequate reduction of proteinuria with MMF. In view of the potential scarring effects, long-term administration beyond the first year requires further documentation.