The effects of cytotoxic therapy in progressive IgA nephropathy

The prognostic effect of immunosuppressive therapy in IgA nephropathy with stage 3 or 4 chronic kidney disease

Background

It is debated whether patients with IgAN with heavy proteinuria and decreased eGFR benefit from aggressive treatment consisting of corticosteroids alone or combined with immunosuppressive agents.

Methods

A retrospective study was performed between January 2008 and December 2016 on patients with IgAN who had urinary protein excretion > 1.0 g/d and an eGFR between 15 and 59 mL/min/1.73 m². These patients were assigned to receive supportive care alone or supportive care plus immunosuppressive therapy. The primary outcome was defined as the first occurrence of a 50% decrease in eGFR or the development of ESKD.

Results

All 208 included patients were followed for a median of 43 months, and 92 (44%) patients experienced the primary outcome. Cumulative kidney survival was better in the immunosuppression group than in the supportive care group (p < .001). The median annual rate of eGFR decline in the immunosuppression group was −2.0 (−7.3 to 4.2), compared with −8.4 (–18.9 to −4.1) mL/min/1.73 m² in the supportive care group (p < .001). In multivariate Cox regression analyses, immunosuppressive therapy was associated with a lower risk of progression to ESKD, independent of age, sex, eGFR, proteinuria, MAP, kidney histologic findings and the use of RASi agents (HR = 0.335; 95% CI 0.209–0.601). Among the adverse events, infection requiring hospitalization occurred at similar rates in both groups (p = .471).

Conclusion

Immunosuppressive therapy attenuated the rate of eGFR decline and was associated with a favorable kidney outcome in IgAN patients with heavy proteinuria and decreased eGFR, and the side effects were tolerable.

Treatment for IgA nephropathy with stage 3 or 4 chronic kidney disease: low-dose corticosteroids combined with oral cyclophosphamide

BACKGROUND

The use of immunosuppressive therapy for IgA nephropathy patients with renal insufficiency and severe proteinuria is controversial.

METHODS

This was a monocentric retrospective study. We reviewed 132 consecutive IgA nephropathy (IgAN) patients with stage 3 or 4 chronic kidney disease and proteinuria ≥ 1.0 g/d who received uncontrolled supportive care (n = 41), corticosteroids (CS) (n = 22) or low-dose CS combined with oral cyclophosphamide (CTX) (n = 69) between January 2008 and December 2016. The combined endpoint was defined as either a ≥ 50% reduction in eGFR or ESRD.

RESULTS

All patients were followed for a medial of 33.2 months, and 67 (50.8%) patients experienced the combined endpoint. The rate of renal function decline was - 4.5 (- 12.6, - 0.1) ml/min/1.73 m² per year. In multivariate Cox regression analyses, immunosuppressive therapy (HR = 0.349, 95% CI 0.194-0.629, P < 0.001) was associated with reduced risk of combined events after adjusting for age, sex, MAP, proteinuria, eGFR, mesangial hypercellularity score > 0.5 (M1), endocapillary hypercellularity present (E1), segmental glomerulosclerosis present (S1), tubular atrophy/interstitial fibrosis > 25% (T1-2), crescents present (C1-2), and RAAS blockers. Immunosuppressive therapy was also analyzed as a categorical variable, and multivariate Cox analyses showed that CS did not reduce the risk of combined events, whereas CS + CTX significantly reduced the risk of combined events. In the matched cohort, the CS + CTX group had a significantly lower reduction in TP-A [1.2 (0.6, 2.3) g/d verse 1.8 (1.2, 2.5), P = 0.023] and a better renal survival rate (39.4% verse 66.7%, P = 0.026) than the uncontrolled supportive care group. The number of hospitalizations required for infection was similar in the three study groups. Other adverse events did not differ significantly among the three groups.

CONCLUSION

Low-dose CS combined with oral CTX treatment is possibly more effective than uncontrolled supportive care for IgAN patients with reduced renal function. The results need to be further confirmed by randomized controlled studies.

Comparison of the effects of valsartan plus activated vitamin D versus valsartan alone in IgA nephropathy with moderate proteinuria

BACKGROUND/AIMS

To compare the effects of valsartan plus activated vitamin D with valsartan alone on urinary protein excretion and eGFR in IgA nephropathy with moderate proteinuria.

METHODS

A prospective, single-center, randomized, controlled study was performed between Jan, 2008 and Jan, 2018 on patients with IgA nephropathy who had moderate proteinuria with urinary protein excretion 1.0-3.0 g/24 h. These IgAN patients were randomly assigned to receive either valsartan 160 mg/day treatment or valsartan 160 mg/day plus activated vitamin D (calcitriol) 0.5 μg/day treatments. The changes of the clinical, biochemical data, and the adverse events during the observation period were all analyzed in the two groups. The primary endpoint was defined as changes in urinary protein excretion at week 24 compared with the baseline and the secondary endpoint was to observe the changes in estimated glomerular filtration rate (eGFR) between baseline and the end of the study.

RESULTS

Baseline characteristics between the two groups were comparable. At the end of the treatment period, urinary protein excretion in both two groups decreased significantly (P < 0.05). However, there was a more significant decrease in proteinuria in IgAN patients who received valsartan plus activated vitamin D treatment (from 2.39 ± 0.77 to 1.43 ± 0.57 g/24 h, P < 0.01) compared to valsartan treatment alone (from 2.46 ± 0.81 to 1.78 ± 0.60 g/24 h, P < 0.05). The percentage change in urine protein excretion at week 24 was  - 40.2% in valsartan plus activated vitamin D treatment group (P < 0.01) and - 27.6% in valsartan treatment group (P < 0.05). No significant change in blood pressure, estimated glomerular filtration rate, serum calcium, and serum potassium was observed. The incidence of adverse events was similar between the two groups, respectively (P > 0.05).

CONCLUSION

Combination therapy with valsartan plus activated vitamin D is more effective than valsartan alone in reduction of moderate proteinuria in IgA nephropathy and without more adverse events.

First-year GFR slope and long-term renal outcome in IgA nephropathy

BACKGROUND

IgA nephropathy (IgAN) is the most frequent primary glomerular disease and the leading cause of end-stage renal disease. We investigated clinicopathologic predictors of renal survival in patients with IgAN with a focus on glomerular filtration rate (GFR) decline slope.

MATERIALS AND METHODS

We screened all patients with primary IgAN between 1995 and 2012. Renal progression was defined as doubling of serum creatinine. Using serial serum creatinine levels during the first-year, we calculated the GFR decline slopes. Further, we defined patients in the steepest GFR slope quartile as rapid decliners and those in the second steepest GFR slope quartile as slow decliners. Others were defined as nondecliners.

RESULTS

Of 214 participants, baseline GFR was 81 (62, 100) mL/min/1.73 m² , which was not different among the 3 groups. Rapid decliners and slow decliners had higher levels of urinary protein/creatinine ratio (0.88, 0.89 and 0.58 g/gCr, respectively, P < .001). Five-year renal survival was 76% in rapid decliners, 91% in slow decliners and 100% in nondecliners (P < .001, rapid or slow decliners vs nondecliners). After adjustment for clinicopathologic variables, slow decliners were associated with an 8.8-fold higher risk of progression (P = .011), and rapid decliners were associated with a 10.2-fold increased risk of progression (P = .007) compared with nondecliners.

CONCLUSIONS

First-year GFR slope was associated with increased risk of renal progression, independent of proteinuria and histologic findings. Further studies are needed to investigate whether early GFR change can identify high-risk patients who benefit from immunosuppressive treatment in IgAN.

Clinical usefulness of the Oxford classification in determining immunosuppressive treatment in IgA nephropathy

BACKGROUND

The Oxford classification has been widely used in IgA nephropathy. However, its clinical usefulness of determining immunosuppression is unknown.

AIM

Whether the Oxford classification could predict the development of proteinuria ≥1 g/g Cr and worsening kidney function, as well as the clinical efficacy of corticosteroid treatment according to each histologic variable of the Oxford-MEST.

METHODS

We included 377 patients with early-stage IgA nephropathy. The study endpoints were the development of a heavy proteinuria and a decline renal function.

RESULTS

The results showed that among the Oxford-MEST lesions, only M1 predicted the risk of the development of proteinuria ≥1.0 g/g Cr compared to other lesions in a time-varying Cox model adjusted for multiple confounding factors. In addition, the risk of reaching a 30% decline in eGFR was significantly higher in patients with M1 than in those with M0. Furthermore, patients with M1 had a greater decline of eGFR than patients with M0. However, steroid treatment in M1 lesion was not associated with improving clinical outcomes in the unmatched and propensity score matched cohort.

CONCLUSIONS

This finding may provide a rationale for using the Oxford classification as a guidance to initiate immunosuppression in the early stages of IgA nephropathy. KEY MESSAGES M1 has independently predictive role among the Oxford lesions in IgA nephropathy. Oxford classification should be defined during pathologic approach. Decision of starting immunosuppression according to the Oxford lesions.

B cell-depleting therapy with rituximab or ofatumumab in immunoglobulin A nephropathy or vasculitis with nephritis

Background

Approximately 30% of adult patients with immunoglobulin A (IgA) nephropathy (IgAN) or IgA vasculitis with nephritis (IgAVN) develop end-stage renal disease during long-term follow-up. In particular, patients with nephritic–nephrotic syndrome have an increased risk of rapid progression. Conventional immunosuppressive therapy with corticosteroids (CSs) may be insufficient for disease control and is associated with a number of side effects. Rituximab (RTX) has been shown to be well tolerated and effective in a range of glomerular diseases, but there is little information on its therapeutic potential in IgAN. The humanized anti-CD20 monoclonal antibody ofatumumab (OFAB) may be an alternative drug for patients intolerant or unresponsive to RTX, but so far there is no report on its use in IgAVN or IgAN.

Methods

We describe clinical outcomes after 17–22 months in four adult patients with biopsy-confirmed IgAVN or IgAN treated with RTX or OFAB as well as CS soon after diagnosis. All presented with nephritic–nephrotic syndrome and one had crescentic IgAN. Rebiopsy was performed in two cases.

Results

RTX and OFAB were well tolerated. Albuminuria was <250 mg/day in three patients at last evaluation and two regained normal renal function. In all cases, renal function improved after therapy. In one patient with severe IgA vasculitis, rebiopsy showed disappearance of subendothelial but not mesangial immune complexes. In the case with crescentic IgAN, rebiopsy after 9 months showed no active necrotic lesions.

Conclusions

B cell–depleting therapy may be an alternative treatment for patients with IgAN or IgAVN and nephritic–nephrotic syndrome. A possible CS-sparing effect should be further evaluated in randomized controlled clinical trials.