Predictors of increase in chronicity index and of kidney function impairment at repeat biopsy in lupus nephritis

OBJECTIVES

Based on available data, the histological predictors of long-term outcome of lupus nephritis (LN) are not clearly defined. Aims of this retrospective study were: (i) to evaluate the change of chronicity index from the first to second kidney biopsy and to find the predictors of chronicity index increase and (ii) to detect the clinical/histological features at first and at second kidney biopsy associated with long-term kidney function impairment.

METHODS

Among 203 biopsy proven LN subjects, 61 repeated kidney biopsy 49 months after the first biopsy. The reasons for repeated biopsy were: nephritic flares in 25 (41%), proteinuric flares in 21 (36%) of patients and protocol biopsy in 14 (23%) of cases.

RESULTS

During 23-year follow-up, 25 patients presented a decrease in glomerular filtration rate (eGFR) ≥30%. At repeat biopsy, chronicity index increased in 44 participants (72%) and did not increase in 17 (28%). Nephritic syndrome and serum creatinine >1.6 mg/dL at presentation correlated with chronicity index increase (p=0.031, 0.027, respectively), cyclophosphamide therapy tended to protect against chronicity index increase (p=0.059). Kidney flares occurred in 53.6% of patients with vs 23.5% of those without chronicity index increase (p=0.035). Chronicity index increases of 3.5 points in patients with kidney flares vs 2 in those without flares (p=0.001). At second, but not at first kidney biopsy, two different models predicted eGFR decrease at multivariate analysis. The first included activity index >3 (OR: 3.230; p=0.013) and chronicity index >4 (OR: 2.905; p=0.010), and the second model included moderate/severe cellular/fibrocellular crescents (OR: 4.207; p=0.010) and interstitial fibrosis (OR: 2.525; p=0.025).

CONCLUSION

At second biopsy, chronicity index increased in 3/4 of participants. Its increase was predicted by kidney dysfunction at presentation and occurrence of LN flares. Kidney function impairment was predicted by both activity and chronicity index and by some of their components at repeated biopsy, but not at first biopsy.

Acute kidney injury and chronic kidney disease after liver transplant: A retrospective observational study

BACKGROUND AND RATIONALE

Chronic kidney disease remains an important risk factor for morbidity and mortality among LT recipients, but its exact incidence and risk factors are still unclear.

MATERIAL AND METHODS

We carried out a retrospective cohort study of consecutive adults who underwent liver transplant (January 2009-December 2018) and were followed (at least 6 months) at our institution. CKD was defined following the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 Clinical Practice Guidelines. Long-term kidney function was classified into 4 groups: no CKD (eGFR, ≥60mL/min/1.73m²), mild CKD (eGFR, 30-59mL/min/1.73m²), severe CKD (eGFR, 15-29mL/min/1.73m²), and end-stage renal disease (ESRD).

RESULTS

We enrolled 410 patients followed for 53.2±32.6 months. 39 had CKD at baseline, and 95 developed de novo CKD over the observation period. There were 184 (44.9%) anti-HCV positive, 47 (11.5%) HBsAg positive, and 33 (8.1%) HBV/HDV positive recipients. Recipient risk factors for baseline CKD were advanced age (P=0.044), raised levels of serum uric acid (P<0.0001), and insulin dependent DM (P=0.0034). Early post-transplant AKI was common (n=95); logistic regression analysis found that baseline serum creatinine was an independent predictor of early post-LT AKI (P=0.0154). According to our Cox proportional hazards model, recipient risk factors for de novo CKD included aging (P<0.0001), early post-transplant AKI (P=0.007), and baseline serum creatinine (P=0.0002). At the end of follow-up, there were 116 LT recipients with CKD - 109 (93.9%) and 7 (6.1%) had stage 3 and advanced CKD, respectively. Only two of them are undergoing long-term dialysis.

CONCLUSION

The incidence of CKD was high in our cohort of LT recipients, but only a slight decline in kidney function over time was recorded. Prevention of post-transplant AKI will improve kidney function in the long run. We need more studies to analyze the function of kidneys among LT recipients over extended follow-ups and their impact on mortality.

Beyond ISN/RPS Lupus Nephritis Classification: Adding Chronicity Index to Clinical Variables Predicts Kidney Survival

Background

A renewed interest for activity and chronicity indices as predictors of lupus nephritis (LN) outcome has emerged. Revised National Institutes of Health activity and chronicity indices have been proposed to classify LN lesions, but they should be validated by future studies. The aims of this study were (1) to detect the histologic features associated with the development of kidney function impairment (KFI), and (2) to identify the best clinical-histologic model to predict KFI at time of kidney biopsy.

Methods

Patients with LN who had more than ten glomeruli per kidney biopsy specimen were admitted to the study. Univariate and multivariate logistic regression and Cox proportional hazards models were used to investigate whether activity and chronicity indices could predict KFI development.

Results

Among 203 participants with LN followed for 14 years, correlations were found between the activity index, and its components, and clinical-laboratory signs of active LN at baseline. The chronicity index was correlated with serum creatinine. Thus, serum creatinine was significantly and directly correlated with both activity and chronicity indices. In the multivariate analysis, glomerulosclerosis (OR, 3.05; 95% CI, 1.17 to 7.91; P=0.02) and fibrous crescents (OR, 6.84; 95% CI, 3.22 to 14.52; P<0.001) associated with either moderate/severe tubular atrophy (OR, 3.17; 95% CI, 1.04 to 9.64; P=0.04), or with interstitial fibrosis (OR, 2.36; 95% CI, 1.05 to 5.32; P=0.04), predicted KFI. Considering both clinical and histologic features, serum creatinine (OR, 1.68; 95% CI, 1.31 to 2.15; P<0.001), arterial hypertension (OR, 4.64; 95% CI, 1.90 to 11.32; P<0.001), glomerulosclerosis (OR, 2.12; 95% CI, 1.00 to 4.50; P=0.05), and fibrous crescents (OR, 5.18; 95% CI, 2.43 to 11.04; P<0.001) independently predicted KFI. Older age (P<0.001) and longer delay between clinical onset of LN and kidney biopsy (P<0.001) were significantly correlated with baseline chronicity index.

Conclusions

The chronicity index and its components, but not the activity index, were significantly associated with an impairment of kidney function. The Cox model showed that serum creatinine, arterial hypertension, chronic glomerular lesions, and delay in kidney biopsy predicted KFI. These data reinforce the importance of timely kidney biopsy in LN.

Calcium carbonate-enriched cheese to improve nutrition, compliance and phosphorus control in patients on kidney replacement therapy

Background

Patients on renal replacement therapy face many dietary limitations, and cheese is often limited because of its high phosphate content; we have developed cheese with added calcium carbonate (CaCO₃) to provide patients with a nutritional opportunity while improving their phosphate control.

Methods

The present double-blind crossover study was aimed to compare the new modified cheese with an equivalent standard product in 16 patients. The increase in inter-dialysis phosphorus (ΔP) and pre-dialysis calcium were used as the primary endpoints for efficacy and safety.

Results

The median ΔP (and IQR) was significantly lower with the modified cheese compared with the standard product: 2.5 (1.9–2.9) mg/dL vs. 2.7 (2.2–3.4) mg/dL, respectively (p < 0.02). No difference was observed in pre-dialysis serum calcium levels.

Conclusions

The described modified cheese may represent an interesting means of overcoming some of the dietary limitations in patients on dialysis to help them achieve better nutrition and quality of life.

Graphic abstract

Acute kidney injury and chronic kidney disease after liver transplant: A retrospective observational study

BACKGROUND AND RATIONALE

Chronic kidney disease remains an important risk factor for morbidity and mortality among LT recipients, but its exact incidence and risk factors are still unclear.

MATERIAL AND METHODS

We carried out a retrospective cohort study of consecutive adults who underwent liver transplant (January 2009-December 2018) and were followed (at least 6 months) at our institution. CKD was defined following the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 Clinical Practice Guidelines. Long-term kidney function was classified into 4 groups: no CKD (eGFR, ≥60mL/min/1.73m2), mild CKD (eGFR, 30-59mL/min/1.73m2), severe CKD (eGFR, 15-29mL/min/1.73m2), and end-stage renal disease (ESRD).

RESULTS

We enrolled 410 patients followed for 53.2±32.6 months. 39 had CKD at baseline, and 95 developed de novo CKD over the observation period. There were 184 (44.9%) anti-HCV positive, 47 (11.5%) HBsAg positive, and 33 (8.1%) HBV/HDV positive recipients. Recipient risk factors for baseline CKD were advanced age (P=0.044), raised levels of serum uric acid (P<0.0001), and insulin dependent DM (P=0.0034). Early post-transplant AKI was common (n=95); logistic regression analysis found that baseline serum creatinine was an independent predictor of early post-LT AKI (P=0.0154). According to our Cox proportional hazards model, recipient risk factors for de novo CKD included aging (P<0.0001), early post-transplant AKI (P=0.007), and baseline serum creatinine (P=0.0002). At the end of follow-up, there were 116 LT recipients with CKD - 109 (93.9%) and 7 (6.1%) had stage 3 and advanced CKD, respectively. Only two of them are undergoing long-term dialysis.

CONCLUSION

The incidence of CKD was high in our cohort of LT recipients, but only a slight decline in kidney function over time was recorded. Prevention of post-transplant AKI will improve kidney function in the long run. We need more studies to analyze the function of kidneys among LT recipients over extended follow-ups and their impact on mortality.

Idiopathic Retroperitoneal Fibrosis: Long-term Risk and Predictors of Relapse

RATIONALE & OBJECTIVE

Idiopathic retroperitoneal fibrosis (IRF) is a rare disorder of unknown cause. Medical therapy can induce remission, but disease relapses are common. This study sought to characterize long-term outcomes of IRF and the factors associated with disease recurrences.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Retrospective analysis of 50 patients with IRF prospectively followed up for 8.9 (IQR, 4.7-12.7) years at a tertiary-care referral center.

EXPOSURES

Demographic, clinical, treatment, and laboratory parameters, including measures of autoimmunity.

OUTCOME

Disease relapse.

ANALYTICAL APPROACH

Proportional hazards analysis for the subdistribution of competing risks.

RESULTS

49 patients received medical treatment and 35 underwent interventional procedures. All patients experienced a clinical response (defined as regression of disease-related symptoms and hydronephrosis, and decrease in the maximal transverse diameter of the retroperitoneal mass on computed tomography of >50%), 44 of whom responded within 1 year. The remaining 6 responded over a median of 2.95 years after starting therapy. 40 patients were alive at last observation, 1 receiving maintenance dialysis and 15 with estimated glomerular filtration rate < 60mL/min/1.73m². Patient survival at 5, 10, and 15 years was 95%, 84%, and 68%, respectively. 19 (38%) patients had at least 1 relapse (occurring a median of 5.19 years after starting therapy), defined as an increase in serum creatinine level of at least 30% or recurrence/development of hydronephrosis and ≥20% increase in the maximal transverse diameter of the retroperitoneal mass on computed tomography. Cumulative incidences of relapse at 5, 10, and 15 years were 21%, 41%, and 48%, respectively. Baseline antinuclear antibody positivity and male sex were associated with relapse (subdistribution hazard ratios [sHRs] of 5.35 [95% CI, 2.15-13.27] and 4.94 [95% CI, 1.32-18.57], respectively), while higher corticosteroid therapy dosage at 1 year (sHR for relapse per 1-mg/d greater dosage, 0.91 [95% CI, 0.84-0.98]) and treatment with prednisone alone or with tamoxifen (sHR for relapse of 0.25 [95% CI, 0.07-0.85] vs other therapies) were associated with lower rate of relapse.

LIMITATIONS

Small sample size and variable approaches to therapy.

CONCLUSIONS

IRF relapses were common and were experienced more frequently by male patients. Corticosteroids alone or with tamoxifen were associated with a lower rate of relapse. The strong association of antinuclear antibody positivity with relapse supports the hypothesis of an autoimmune pathogenesis of IRF.

Causes of late transplant failure in cyclosporine-treated kidney allograft recipients

BACKGROUND

There is little information about very long-term outcomes of kidney allograft recipients exposed to calcineurin inhibitors.

METHODS

In this single-centre retrospective study with 20-year follow-up, we analyzed data from 644 patients who underwent primary renal transplantation between 1983 and 1993. Participants were treated with a cyclosporine-based immunosuppressive scheme and had allograft function at 1 year.

RESULTS

After 20 years, 15.2% patients died, 39.7% experienced allograft loss, 26.8% were alive with a functioning transplant, and 18.2% were lost to follow-up. Cardiovascular disease (30.8%), malignancy (26.6%) and infection (17.0%) were the main causes of death. Age, new-onset proteinuria > 1 g/day, major acute cardiovascular event (MACE), and malignancy were independent predictors of mortality at time-dependent multivariate analysis. Chronic rejection (63.3%), recurrent glomerulonephritis (14.0%), and nonspecific interstitial fibrosis/tubular atrophy (13.2%) were the leading cause of allograft loss. Basal disease, hepatitis C, difference between 1 year and nadir serum creatinine, new-onset proteinuria > 1 g/day, and MACE were independent predictors of transplant failure. Among patients with 20-year allograft function, we recorded the following complications: hypertension (85%), malignancy (13%), diabetes (9%), and cardiovascular disease (9%). Median serum creatinine and proteinuria were 1.4 mg/dL and 0.6 g/day, respectively.

CONCLUSIONS

Prolonged use of cyclosporine may expose to several dose-related adverse events and may contribute to the development of allograft dysfunction but it does not necessarily cause relentless, progressive transplant failure if patients are carefully and consistently monitored during the follow-up.

Changing patterns in clinical-histological presentation and renal outcome over the last five decades in a cohort of 499 patients with lupus nephritis

OBJECTIVES

To evaluate changes in demographic, clinical and histological presentation, and prognosis of lupus nephritis (LN) over time.

PATIENTS AND METHODS

We studied a multicentre cohort of 499 patients diagnosed with LN from 1970 to 2016. The 46-year follow-up was subdivided into three periods (P): P1 1970-1985, P2 1986-2001 and P3 2002-2016, and patients accordingly grouped based on the year of LN diagnosis. Predictors of patient and renal survival were investigated by univariate and multivariate proportional hazards Cox regression analyses. Survival curves were compared using the log-rank test.

RESULTS

A progressive increase in patient age at the time of LN diagnosis (p<0.0001) and a longer time between systemic lupus erythematosus onset and LN occurrence (p<0.0001) was observed from 1970 to 2016. During the same period, the frequency of renal insufficiency at the time of LN presentation progressively decreased (p<0.0001) and that of isolated urinary abnormalities increased (p<0.0001). No changes in histological class and activity index were observed, while chronicity index significantly decreased from 1970 to 2016 (p=0.023). Survival without end-stage renal disease (ESRD) was 87% in P1, 94% in P2% and 99% in P3 at 10 years, 80% in P1 and 90% in P2 at 20 years (p=0.0019). At multivariate analysis, male gender, arterial hypertension, absence of maintenance immunosuppressive therapy, increased serum creatinine, and high activity and chronicity index were independent predictors of ESRD.

CONCLUSIONS

Clinical presentation of LN has become less severe in the last years, leading to a better long-term renal survival.

Low-dose rituximab is poorly effective in patients with primary membranous nephropathy

Background

The optimal dosing and the efficacy of rituximab for primary membranous nephropathy (PMN) has not been established. This multicentric prospective study evaluates the efficacy and safety of low-dose rituximab (RTX) therapy in patients with PMN in clinical practice.

Methods

Thirty-four consecutive patients with PMN and nephrotic syndrome were included and received RTX (375 mg/m2) once (18 patients) or twice (16 patients). RTX was the first-line therapy for 19 (56%) and the second line for 15 (44%) patients. All patients were followed for 12 months after RTX and 24 for at least 18 months (mean 23.9 ± 18.6 months).

Results

At 12 months, 5 patients (14.7%) achieved complete response, 10 (29.4%) partial and 19 (55.8%) no response. Response occurred ∼6 months after RTX. At 24 months, the clinical situation was unchanged: two non-responders achieved partial response and two responders relapsed. Responders had significantly higher baseline GFR and lower anti-PLA2R antibodies compared with non-responders. Outcome was similar between one or two doses of RTX (non-responders 55.5 versus 56%, respectively) and between patients who had received previous therapy versus those receiving RTX as first-line therapy (non-responders 40 versus 68%, respectively). In the 15 patients already treated, the response to RTX was comparable to that of previous therapies.

Conclusion

Low-dose RTX obtains remission in <50% of PMN patients. Probably, higher doses and longer treatments are needed to induce and maintain a response. The balance between the costs and benefits should guide the selection of the patient and the optimal dosage.

Efficacy and safety of off-label use of rituximab in refractory lupus: data from the Italian Multicentre Registry

OBJECTIVES

To evaluate the efficacy and safety of rituximab (RTX) in patients with systemic lupus erythematosus (SLE) refractory to standard therapy in the clinical practice setting.

METHODS

145 SLE patients (ACR criteria) were treated with RTX in 11 Italian Centres: 118 with two infusions (1 g), two weeks apart; 27 with 4 infusions (375 mg/m2), one week apart, followed in 10 cases by two further doses, after 1 and 2 months. Systemic complete response (CR) was defined as European Consensus Lupus Activity Measurement (ECLAM) score ≤1 and partial response (PR) as 1< ECLAM ≤3. Renal CR (RCR) and renal PR (RPR) were defined according to EULAR recommendations for management of lupus nephritis.

RESULTS

Data from 134 (92.4%) patients were available. The mean±SD follow-up was 27.3±18.5 months. After the first course of RTX, CR or PR were observed in 85.8% and CR in 45.5% of cases; RCR or RPR in 94.1% and RCR in 30.9% of patients after 12-month follow-up. Disease flares occurred in 35.1% and renal flares in 31.2% of patients during observational period. Among patients retreated, CR or PR were observed in 84.4% and CR in 57.8% of cases. Adverse events, infections, and infusion reactions occurred after first RTX course in 23.8%, 16.4%, and 3.8% of patients and after retreatment in 33.3%, 22.2% and 11.1%, respectively. No severe infusion reactions or deaths occurred.

CONCLUSIONS

Data from Italian multicentre RTX Registry confirmed the efficacy and safety of RTX in SLE patients refractory to standard treatment in clinical practice setting.

Predictors of renal survival in ANCA-associated vasculitis. Validation of a histopatological classification schema and review of the literature

OBJECTIVES

In 2010 a histopathological classification of ANCA-associated glomerulonephritis was proposed to predict the outcomes at diagnosis. Our aim was to validate the proposed classification in our cohort of patients and to compare the studies already published.

METHODS

The data of 93 patients who underwent kidney biopsy in a single Italian centre within 15 years were retrospectively collected.

RESULTS

The 10-year renal and patients' survival were 60% and 81%, respectively. Biopsies were classified as 21% focal, 30% crescentic, 39% mixed and 10% sclerotic. Survival without ESRD at 5 years was 82% in focal, 37% in crescentic, 81% in mixed and 51% in sclerotic group. The Kaplan-Meier analysis highlights that renal survival was not different between sclerotic and crescentic groups (p=0.9) but both had a significantly worse prognosis than focal (p=0.04 and 0.015 respectively) and mixed groups (p=0.05 and 0.03 respectively). Focal and mixed groups had the same renal survival (p=0.7). At multivariate analysis the independent predictors of end-stage renal disease were less than 20% of normal glomeruli at kidney biopsy (p=0.022), high serum creatinine (p=0.009) and arterial hypertension at presentation (p= 0.006).

CONCLUSIONS

In our cohort, the proposed histological classification was not predictive of renal prognosis. The focal and the mixed classes had the same prognosis and a significantly better renal outcome than both the crescentic and the sclerotic classes. At multivariate analysis among the histological features only less than 20% of normal glomeruli defines the renal prognosis together with renal function and arterial hypertension at baseline.

Value of a commercial kit for detecting anti-C1q autoantibodies and correlation with immunological and clinical activity of lupus nephritis

The association of anti-C1q antibodies (anti-C1q) with the renal activity of lupus nephritis (LN) and the methods for their determination is still a matter of debate.

In 116 serum samples of 66 patients with biopsy proven LN, we aimed: 1) to compare the results of the determination of anti-C1q obtained by a commercial kit with a clinically validated in-house ELISA; 2) to evaluate the correlation of anti-C1q with the most important immunological and clinical parameters employed in LN, i.e., antibodies to dsDNA (anti-dsDNA), C3 and C4 complement component, haemoglobin and haematuria.

Good correlation and agreement between the two methods (r=0.81, p<0.0001; contingency coefficient=0.70, p<0.0001, respectively) were demonstrated. No differences were observed between the two assays by ROC curves comparison. Anti-C1q levels were significantly higher in patients with active LN [44 arbitrary units (AUs)] in comparison to those with inactive LN (23 AUs, p=0.047) and significantly correlated with anti-dsDNA (r=0.44, p<0.0001), complement fractions (C3: r=−0.33, p=0.001; C4: r=−0.29, p=0.003), haemoglobin levels (r=−0.34, p=0.0004) and the number of urinary red blood cells (r=0.26, p=0.01).

Our results suggest the validity of this commercial assay in detecting anti-C1q and confirm the association of anti-C1q with renal involvement of LN and the importance of introducing this parameter in the analytical panel for the evaluation of LN activity.

Rituximab vs mycophenolate and vs cyclophosphamide pulses for induction therapy of active lupus nephritis: a clinical observational study

OBJECTIVE

We report the first comparison between rituximab (RTX) and either MMF or CYC pulses in the treatment of active LN.

METHODS

Fifty-four patients with active LN received three methylprednisolone pulses for 3 consecutive days followed by oral prednisone and RTX 1 g at days 3 and 18 (17 patients) or MMF 2-2.5 g/day (17 patients) or six CYC pulses (0.5 g every fortnight) (20 patients). At 4 months MMF, AZA or ciclosporin were associated to prednisone as a consolidation/maintenance therapy in all groups. The outcomes of the three groups were compared at 3 and 12 months.

RESULTS

Patients in the RTX group were older, had a longer duration of SLE and LN, had more renal flares, had higher activity and had higher chronicity indexes at renal biopsy than the other two groups. Four patients in each group had acute renal dysfunction and ∼50% had nephrotic syndrome. At 3 months, proteinuria was reduced by 50% in 58.8% of patients on RTX, in 64.7% on MMF and in 63.1% on CYC. At 12 months, complete remission was present in 70.6% of patients on RTX, in 52.9% on MMF, and in 65% on CYC. Partial remission was reached in 29.4% on RTX, 41.2% on MMF, and 25% on CYC.

CONCLUSION

RTX seems to be at least as effective as MMF and CYC pulses in inducing remission. Considering that patients treated with RTX had more negative renal prognostic factors, this drug should be considered a viable alternative for the treatment of active LN.