Nonlupus nephritides in patients with systemic lupus erythematosus: a comprehensive clinicopathologic study and review of the literature

II Brazilian Society of Rheumatology consensus for lupus nephritis diagnosis and treatment

OBJECTIVE

To develop the second evidence-based Brazilian Society of Rheumatology consensus for diagnosis and treatment of lupus nephritis (LN).

METHODS

Two methodologists and 20 rheumatologists from Lupus Comittee of Brazilian Society of Rheumatology participate in the development of this guideline. Fourteen PICO questions were defined and a systematic review was performed. Eligible randomized controlled trials were analyzed regarding complete renal remission, partial renal remission, serum creatinine, proteinuria, serum creatinine doubling, progression to end-stage renal disease, renal relapse, and severe adverse events (infections and mortality). The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to develop these recommendations. Recommendations required ≥82% of agreement among the voting members and were classified as strongly in favor, weakly in favor, conditional, weakly against or strongly against a particular intervention. Other aspects of LN management (diagnosis, general principles of treatment, treatment of comorbidities and refractory cases) were evaluated through literature review and expert opinion.

RESULTS

All SLE patients should undergo creatinine and urinalysis tests to assess renal involvement. Kidney biopsy is considered the gold standard for diagnosing LN but, if it is not available or there is a contraindication to the procedure, therapeutic decisions should be based on clinical and laboratory parameters. Fourteen recommendations were developed. Target Renal response (TRR) was defined as improvement or maintenance of renal function (±10% at baseline of treatment) combined with a decrease in 24-h proteinuria or 24-h UPCR of 25% at 3 months, a decrease of 50% at 6 months, and proteinuria < 0.8 g/24 h at 12 months. Hydroxychloroquine should be prescribed to all SLE patients, except in cases of contraindication. Glucocorticoids should be used at the lowest dose and for the minimal necessary period. In class III or IV (±V), mycophenolate (MMF), cyclophosphamide, MMF plus tacrolimus (TAC), MMF plus belimumab or TAC can be used as induction therapy. For maintenance therapy, MMF or azathioprine (AZA) are the first choice and TAC or cyclosporin or leflunomide can be used in patients who cannot use MMF or AZA. Rituximab can be prescribed in cases of refractory disease. In cases of failure in achieving TRR, it is important to assess adherence, immunosuppressant dosage, adjuvant therapy, comorbidities, and consider biopsy/rebiopsy.

CONCLUSION

This consensus provides evidence-based data to guide LN diagnosis and treatment, supporting the development of public and supplementary health policies in Brazil.

Differences in management approaches for lupus nephritis within the UK

Objectives

Outcomes of therapy for LN are often suboptimal. Guidelines offer varied options for treatment of LN and treatment strategies may differ between clinicians and regions. We aimed to assess variations in the usual practice of UK physicians who treat LN.

Methods

We conducted an online survey of simulated LN cases for UK rheumatologists and nephrologists to identify treatment preferences for class IV and class V LN.

Results

Of 77 respondents, 48 (62.3%) were rheumatologists and 29 (37.7%) were nephrologists. A total of 37 (48.0%) reported having a joint clinic between nephrologists and rheumatologists, 54 (70.0%) reported having a multidisciplinary team meeting for LN and 26 (33.7%) reported having a specialized lupus nurse. Of the respondents, 58 (75%) reported arranging a renal biopsy before starting the treatment. A total of 20 (69%) of the nephrologists, but only 13 (27%) rheumatologists, reported having a formal departmental protocol for treating patients with LN (P < 0.001). The first-choice treatment of class IV LN in pre-menopausal patients was MMF [41 (53.2%)], followed by CYC [15 (19.6%)], rituximab [RTX; 12 (12.5%)] or a combination of immunosuppressive drugs [9 (11.7%)] with differences between nephrologists' and rheumatologists' choices (P = 0.026). For class V LN, MMF was the preferred initial treatment, irrespective of whether proteinuria was in the nephrotic range or not. RTX was the preferred second-line therapy for non-responders.

Conclusion

There was variation in the use of protocols, specialist clinic service provision, biopsies and primary and secondary treatment choices for LN reported by nephrologists and rheumatologists in the UK.

Kidney Biopsy in Management of Lupus Nephritis: A Case-Based Narrative Review

Kidney involvement in patients with lupus highly increases morbidity and mortality. In recent years, several reports have emphasized the dissociation between clinical and histological findings and highlighted the role of kidney biopsy as an instrument for diagnosis and follow-up of lupus nephritis. The kidney biopsy at initial diagnosis allows an early diagnosis, assessment of activity and chronicity, and detection of nonimmune complex nephritis. A kidney biopsy repeated months after treatment aids in the detection of persistent histological inflammation, which has been linked to the occurrence of future kidney relapses. A kidney biopsy at a relapse detects histological changes including chronic scarring. Finally, a kidney biopsy in patients with a clinical response undergoing maintenance immunosuppression may aid therapy tapering and/or suspension. The evidence supporting the use of a kidney biopsy in different scenarios across the course of lupus nephritis is heterogeneous, with most reports assessing the value for the diagnosis of a first or relapsing flare. In contrast, less evidence suggests additional therapeutic-modifying information derived from repeat posttreatment biopsies and biopsies to evaluate treatment tapering or suspension. In this clinical case-based review, we examine the role of kidney biopsy as a tool to improve clinical outcomes of patients with lupus nephritis.

Unmasking Renal Disease in Systemic Lupus Erythematosus: Beyond Lupus Nephritis

A 64-year-old Caucasian woman with a history of hypertension and systemic lupus erythematosus (SLE) was referred to a nephrology clinic due to persistent microscopic hematuria and trace proteinuria. Initial tests showed elevated antinuclear antibodies (ANA), anti-double-stranded DNA (anti-dsDNA), and anti-Sjögren's syndrome-related antigen A (anti-SSA) levels, while other markers remained within normal limits. Over the course of a year, her urine protein-creatinine ratio increased, prompting a renal biopsy. The biopsy revealed focal crescent formation in some glomeruli and mild segmental mesangial hypercellularity in others. Although the possibility of antineutrophilic cytoplasmic antibody (ANCA)-associated nephritis with superimposed IgA nephropathy was considered, negative myeloperoxidase and proteinase 3 antibody tests led to a final diagnosis of IgA nephropathy. The patient's treatment included adding prednisone to her existing valsartan prescription for hypertension, which resulted in improved proteinuria. SLE is an autoimmune disease that can cause chronic inflammation and damage to vital organs. Approximately 50% of SLE patients may experience lupus nephritis (LN), underscoring the importance of urinalysis and renal function tests. This case presents a female patient with SLE and IgA nephropathy, a rare association that requires distinction as it affects disease management. IgA nephropathy is the most common cause of idiopathic glomerulonephritis and can lead to end-stage kidney disease in around 40% of cases. A renal biopsy is also crucial for diagnosing IgA nephropathy in patients with or without another autoimmune disease. Focal crescent formation, a histological feature observed in this case, helped exclude several diagnoses, such as lupus nephritis or pauci-immune glomerulonephritis. The primary goal of treating IgA nephropathy is to prevent disease progression. Initial treatment includes controlling blood pressure, reducing proteinuria, and implementing lifestyle modifications. Corticosteroid therapy may be considered if supportive care is insufficient.

Differences and similarities of proliferative and non-proliferative forms of biopsy-proven lupus nephritis: Single centre, cross-disciplinary experience

OBJECTIVE

We aimed to compare clinical features, outcomes, treatments, and to define the predictive factors of complete renal response (CRR) in patients with proliferative and non-proliferative lupus nephritis (LN).

METHODS

Patients with systemic lupus erythematosus (SLE) followed between 2014 and 2020 at Hacettepe University Hospitals and who had a kidney biopsy were the subject of the study. One hundered and sixteen patients' kidney biopsies reported as LN were evaluated retrospectively. Clinical characteristics and laboratory values at the time of kidney biopsy, histopathological forms of LN, and renal response (complete or partial) were recorded. We analyzed the association between CRR rates during the 2-year follow-up after induction therapy and the predictive factors for CRR.

RESULTS

Of 116 (93 females, 23 males) patients, 95 (81.9%) were in the proliferative group (class III and IV) and 21 (18.1%) were in the non-proliferative group (class II and V). In the proliferative group, the percentage of the patients with elevated basal creatinine levels, median daily proteinuria, anti-double-stranded DNA (dsDNA) positivity, low C3 and C4 levels, the presence of active urinary sediment, and median renal SLE Disease Activity Index (SLEDAI) scores at the time of kidney biopsy were significantly higher than the non-proliferative group. Renal response status during the 2-year follow-up after induction therapy was available for 99 patients. During this time, 70 (70.7%) patients had achieved CRR and time-to-CRR was similar between the proliferative and non-proliferative groups (p = 0.64, log-rank test). The Cox proportional hazards model showed that achievement of CRR was associated with female gender [HR: 2.15 (1.19-3.89 95% CI), p = 0.011], newly diagnosed SLE with renal biopsy [HR: 2.15 (1.26-3.67 95% CI), p = 0.005], hypertension [HR: 0.40 (0.27-0.94 95% CI), p = 0.032], eGFR increase [HR: 1.01 (1.00-1.01 95% CI), p = 0.046], and the presence of active urinary sediment [HR: 0.46 (0.22-0.96 95% CI), p = 0.039].

CONCLUSIONS

Achieving CRR was similar in proliferative and non-proliferative LN patients, although certain laboratory parameters differed at the onset. Our results indicated the importance of kidney biopsy in the decision-making of treatment of SLE patients with renal involvement and that the defined factors associated with CRR achievement help to predict good renal response.

Predominant mesangial IgM, C3, and λ light chain depositions and interstitial nephritis in a patient with overlap syndrome and positivity for anti-mitochondrial M2 antibody: a case report

Overlap syndrome refers to a group of conditions that have clinical features of more than one well-characterised rheumatic disease and meet the respective classification criteria. There are no typical renal histological findings in overlap syndrome. When patients with overlap syndrome develop renal dysfunction, various potential causes, including lupus nephritis (LN), renal crisis by systemic sclerosis, interstitial nephritis, and so on, need to be distinguished. Here, we report a 44-year-old woman with overlap syndrome involving systemic lupus erythematosus (SLE), diffuse cutaneous systemic scleroderma, and Sjogren's syndrome, who was also positive for anti-mitochondrial M2 antibody. She developed glomerular haematuria, proteinuria, and increase in creatinine appeared gradually. Suspecting LN, renal biopsy was performed. However, in the interstitium, mild infiltration of lymphocytes and plasma cells and very partial fibrosis were observed. Immunofluorescence microscopy revealed predominant mesangial immunoglobulin M, C3, and λ light chain staining. Overall, LN was not diagnosed based on these findings. Renal dysfunction was normalised by glucocorticoid treatment for 3 months. This case suggests the importance of a renal diagnosis based on renal pathological findings, especially in a case of overlap syndrome including SLE.

Lupus Nephritis: The Significant Contribution of Electron Microscopy

Background

Systemic lupus erythematosus (SLE) represents a principal prototype of a multisystemic autoimmune disease with the participation of both cell- and antibody-mediated mechanisms causing significant renal impairment. A renal biopsy diagnosis is the gold standard for clinical renal disease in SLE, which includes a broad range of indications.

Summary

Renal disease in SLE can involve glomerular, tubulointerstitial, and/or vascular compartments, none of which are mutually exclusive. In most instances, the basic pathogenetic mechanism involves tissue deposition of immune complexes and/or cell-mediated mechanisms, identified by light microscopy, immunohistochemical methods, and electron microscopy (EM), evoking intraglomerular proliferative, inflammatory, and other tissue responses. These produce a spectrum of histologic lesions, depending on the participation of a wide range of clinical triggers, namely, genetic, serological, and immunological factors, correlating with their underlying pathogenetic potential. In addition to light and immunofluorescence microscopy, EM in this setting facilitates an accurate diagnosis, assesses disease activity, delineates subclasses, differentiates from primary forms of non-lupus renal lesions, identifies organized deposits, and rarely, identifies other forms of nonimmune complex lesions such as podocytopathies, amyloidosis, and thrombotic microangiopathy.

Key Messages

EM findings that are distinctive for most of the renal lesions in SLE include immune complex and nonimmune complex diseases as well as overlapping entities. Routine ultrastructural examination not only provides significant diagnostic and prognostic information from both initial and repeat renal biopsies from lupus patients but also contributes toward the understanding of the underlying pathophysiology of the disease process.

Study of the relationship between urinary level of uromodulin, renal involvement and disease activity in patients with systemic lupus erythrematosus

Systemic lupus erythematosus (SLE) is a multifactorial chronic inflammatory autoimmune connective tissue disease. Lupus nephritis (LN) is a common and serious complication of SLE which can progress to end-stage renal disease. Renal biopsy is the gold standard in the diagnosis and classification of LN, but since it is an invasive procedure, it is neither desirable nor applicable for all cases. This has led to the search for an alternative, noninvasive, site-specific, and immune process-related biomarkers. Uromodulin (Tamm-Horsfall glycoprotein) is the most abundant urinary protein expressed exclusively by the thick ascending limb cells and released into urine of healthy controls. Studies showed that it may act as a danger signaling molecule eliciting an inflammatory response following conditions that damage the nephron integrity and leading to uromodulin release into the interstitial space. This study aimed to assess uromodulin as a screening biomarker of tubulointerstitial involvement in patients with SLE and to elucidate its correlation with disease activity and progression. The study was conducted on 70 patients divided into two groups: control group (Group I) consisted of 20 apparently healthy volunteers of comparable age and sex to the patients' group, and 50 SLE patients (Group II) diagnosed according to the 2012 Systemic Lupus Collaborating Clinics (SLICC) classification criteria. Group II was further subdivided into 23 patients without manifestations of LN (Group II A) and 27 patients with manifestations of LN (Group II B). Urinary uromodulin level showed statistically significant difference among the studied groups, being lowest among the LN patients with a mean value 5.6 ± 3.4, in SLE patients without nephritis 9.9 ± 5.2 and 12.9 ± 4.6 in the control group. Urinary uromodulin also correlated positively with estimated glome- rular filtration rate. A negative correlation was found between urinary uromodulin and serum creatinine, 24 h urinary proteins and SLICC renal activity score. No statistically significant correlation was found between urinary uromo- dulin and SLE disease activity index. Thus, decreasing urinary uromodulin levels can be a marker for renal involvement and tubulo- interstitial nephritis in active SLE patients and a marker for chronic kidney disease and nephron loss in the absence of activity markers.

Clinical impact of repeat renal biopsies in patients with lupus nephritis: Renal biopsy is essential especially later in the course of the disease

OBJECTIVE

The clinical impact of repeat renal biopsies in patients with lupus nephritis (LN) is still debatable. The aim of this retrospective analysis was to assess whether repeat renal biopsy is a reliable tool in guiding therapeutic decisions.

METHODS

Laboratory and histological parameters and therapeutic changes in 35 patients with LN and repeat renal biopsies were retrospectively analyzed. Biopsies were performed in the presence of clinical evidence of an active glomerular disease. Biopsy specimens were retrospectively re-assessed by two renal pathologists and were compared according to the last International Society of Nephrology/ Renal Pathology Society classification.

RESULTS

Thirty-five patients had two, 13 had three, 5 had four, 4 had five, and 1 had six renal biopsies. Fifty-eight comparisons of renal biopsies were made. Median times between the first and second, second and third, third and fourth, and fourth and fifth biopsies were 31, 27, 34, and 28 months, respectively. The mean activity indices from the first to the fifth biopsy were 8.7, 6.6, 7.8, 9.4, and 4.7, whereas the mean chronicity indices were 1.7, 2.3, 4.3, 5.2, and 7.7, respectively. Conversion was observed in 65.5% of cases with the most frequent (21%) being between classes III and IV. Conversion to a more severe type of nephritis occurred in 19% of cases. There was no correlation of laboratory parameters to the type of nephritis upon conversion. In 79% of cases, immunosuppressive therapy was modified after repeat biopsy.

CONCLUSION

Repeat biopsy is a reliable tool for monitoring the activity and chronicity status of LN and for tailoring immunosuppressive therapy to the needs of the patient, especially late in the course of the disease.

A review of non-immune mediated kidney disease in systemic lupus erythematosus: A hypothetical model of putative risk factors

About half of patients with systemic lupus erythematosus (SLE) are diagnosed with lupus nephritis (LN). Patients with SLE are also at increased risk for diabetes, hypertension and obesity, which together account for >70% of end-stage renal disease in the general population. The frequencies of non-LN related causes of kidney disease, and their contribution to kidney disease development and progression among patients with SLE have been inadequately studied. We hypothesize that a substantial, and increasing proportion of kidney pathology in patients with SLE might not directly relate to LN but instead might be explained by non-immune mediated factors such as diabetes, hypertension, and obesity. The goal of the manuscript is to draw attention to hypertension, diabetes and obesity as potential alternative causes of kidney damage in patients with SLE. Further, we suggest that misclassification of kidney disease etiology in patients with SLE might have important ramifications for clinical trial recruitment, epidemiologic investigation, and clinical care. Future studies aiming to elucidate and distinguish discrete causes of kidney disease - both clinically and histologically - among patients with SLE are desperately needed as improved understanding of disease mechanisms is paramount to advancing therapeutic discovery. Collaboration among rheumatologists, pathologists, nephrologists, and endocrinologists, and the availability of dedicated research funding, will be critical to the success of such efforts.

The Kidney Biopsy in Systemic Lupus Erythematosus: A View of the Past and a Vision of the Future

The kidney biopsy advanced our understanding of kidney disease in systemic lupus erythematosus. It allowed for better recognition and classification of lupus nephritis (LN). Several LN classifications have been devised in an effort to inform treatment decision and predict prognosis, and these are being further updated. In this review, we will examine the role of diagnostic as well as repeat kidney biopsy in the management of LN, including the potential role of molecular interrogation as a step forward beyond conventional histology to guide the discovery of novel biomarkers and a precision medicine approach to the management of LN.

[Lupus nephritis]

Systemic lupus erythematosus is the most characteristic of auto-immune disorders that can lead to tissue damage in many organs, including kidney. Lupus nephritis occurs in 10 to 40% of lupus patients. Its clinical hallmark is the appearance of a proteinuria as soon as a 0.5 g/g or 0.5 g/d threshold, which calls for a renal histological evaluation in order to determine the lupus nephritis severity and the need for specific therapy. More than half of renal biopsies lead to the diagnosis of active lupus nephritis-class III or class IV A according to the ISN/RPS classification-that are the most severe in regards to renal prognosis and mortality. Their treatment aims to their clinical remission and to the prevention of relapse with minimal adverse effects for eventually the preservation of renal function, the prevention of other irreversible damage, and the reduction of risk of death. The remission is obtained through induction therapies of which the association of high dose steroids and cyclophosphamide is the most experienced. When this association must be challenged by the prevention of side-effect, in particular infertility, mycophenolate can be given instead of cyclophosphamide. Maintenance therapy, for the prevention of relapse, consists in mycophenolate or in azathioprine, mycophenolate being the most efficient however associated with a high risk of teratogenicity. Withdrawal of maintenance therapy is possible after two to three years in absence of high risk factors of relapse of lupus nephritis, however a reliable assessment of the risk of relapse is still lacking. Only pure membranous lupus nephritis (pure class V) associated with high level proteinuria requires specific therapies that usually associates steroids and an immunosuppressive drug. However, their choice hierarchy and even the use of less immunosuppressive strategies remain to be determined in terms of benefice over risk ratios. In spite of its trigger effect on lupus activity, pregnancy can be safe and successful if scheduled in the lowest risk periods with close multidisciplinary monitoring before, during and after. When necessary, renal replacement therapy does not require specific adaptation, renal transplantation is the best option when possible, as early as possible.

The Impact of Protein Acetylation/Deacetylation on Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease in which the body’s immune system mistakenly attacks healthy cells. Although the exact cause of SLE has not been identified, it is clear that both genetics and environmental factors trigger the disease. Identical twins have a 24% chance of getting lupus disease if the other one is affected. Internal factors such as female gender and sex hormones, the major histocompatibility complex (MHC) locus and other genetic polymorphisms have been shown to affect SLE, as well as external, environmental influences such as sunlight exposure, smoking, vitamin D deficiency, and certain infections. Several studies have reported and proposed multiple associations between the alteration of the epigenome and the pathogenesis of autoimmune disease. Epigenetic factors contributing to SLE include microRNAs, DNA methylation status, and the acetylation/deacetylation of histone proteins. Additionally, the acetylation of non-histone proteins can also influence cellular function. A better understanding of non-genomic factors that regulate SLE will provide insight into the mechanisms that initiate and facilitate disease and also contribute to the development of novel therapeutics that can specifically target pathogenic molecular pathways.

The clinical relevance of repeat renal biopsies in the management of lupus nephritis: a South African experience

Purpose Clinically, repeat renal biopsies (RRBs) have been performed in lupus nephritis to identify changes in class, plan treatment and assist in prognostication. We set out to compare the histopathological features and outcomes of disease flare and protocol biopsy patients. Methods A retrospective descriptive study was conducted on repeat biopsies performed between January 1984 and December 2015 in lupus nephritis patients. Disease flares and protocol biopsies were compared. Results Of 614 systemic lupus erythematosus (SLE) renal biopsies, 127 (20.7%) RRBs were identified. Disease flare patients accounted for 96 (75.6%) and protocol biopsies for 31 (24.4%) of RRBs. Seventy (72.9%) disease flare patients retained their original class on repeat biopsy. When categorised as proliferative and non-proliferative histology, 83 (87.4%) of the disease flare biopsy patients remained histologically unchanged. Treatment remained unchanged in 57 (60.0%) patients following RRBs for disease flares. Response to immunosuppression in disease flare patients was poorer. Non-response was associated with increased chronicity index (OR = 1.33; 95% CI 1.01-1.76; p = 0.045). Thirty-three (36.3%) disease flare patients developed end-stage kidney disease (ESKD) in one year as compared to one (3.6%) protocol biopsy patient ( p = 0.003). ESKD in disease flare patients was associated with non-response to treatment (OR = 24.6; 95% CI 2.7-219.3; p = 0.004) on multivariate analysis. One-year mortality was 30.0% in the disease flare patients and 3.5% in protocol biopsy patients ( p = 0.018). Conclusion Repeat biopsies in disease flare patients infrequently led to histological class changes, failed to lead to change of treatment in the majority of patients, and were associated with poorer outcomes.

Prognostic significance of repeat biopsy in lupus nephritis: Histopathologic worsening and a short time between biopsies is associated with significantly increased risk for end stage renal disease and death

BACKGROUND/PURPOSE

Approximately half of patients with systemic lupus erythematosus (SLE) develop lupus nephritis (LN), a major cause of morbidity and early mortality in that disease. Prolonged renal inflammation is associated with irreversible kidney damage which confers a 30% risk of end stage renal disease (ESRD), making early, aggressive treatment mandatory. Failure to achieve therapeutic response or recurrence of renal flare often prompts repeat biopsy. However, the role of repeat biopsy in determining long-term renal prognosis remains controversial. For this reason repeat biopsies are usually not utilized unless clinical evidence of refractory or recurrent disease is already present, despite known mismatches between clinical and biopsy findings. The current study quantifies the degree to which histopathologic worsening between first and second biopsies and duration between them predicts ESRD and death.

METHODS

Medical records of 141 LN patients with more than one biopsy were obtained from a single large urban medical center. Cases were attained using billing codes for diagnosis and procedures from 1/1999-1/2015. Biopsy worsening was defined as unfavorable histopathologic classification transitions and/or increased chronicity; if neither were present, the patient was defined as non-worsening. We used Cox proportional hazard models to study the relationship between ESRD and survival adjusting for covariates which included age at first biopsy, gender, race, initial biopsy class, and initial induction therapy.

RESULTS

Of 630 patients screened, 141 had more than one biopsy. Advancing chronicity was detected in 48 (34.0%) and a renal class switch to worse grade of pathology was found in 54 (38.3%). At least one of these adverse second biopsy features was reported in 79 (56.0%) patients. Five years following initial biopsy, 28 (35.4%) of those with worsening histopathology on second biopsy developed ESRD, compared to 6 (9.7%) of non-worsening patients and 10 (12.7%) of patients with worsening histopathology had died compared to 2 (3.2%) of non-worsening patients. Biopsy worsening was associated with a significantly greater 15-year risk of ESRD (Hazard Ratio 4.2, p=0.0001) and death (Hazard Ratio 4.3, p=0.022), adjusting for age, gender, race, biopsy class, and treatment. Time between first and second biopsies was <1year in 32 patients, 1-5years in 81, and >5years in 28. Over a 15-year period, those with <1year between first and second biopsies (presumably enriched for patients with early clinical signs of progression) had a significantly greater risk of ESRD (Hazard Ratio 13.7, p<0.0001) and death (Hazard Ratio 16.9, p=0.0022) after adjusting for age, gender, race, biopsy class, and treatment.

CONCLUSION

A repeat renal biopsy demonstrating worsening pathology increases the risk of ESRD and death more than four-fold compared to non-worsening patients. Given known potential mismatch between biopsy and clinical data, repeat biopsies may add important information and justify changes in treatment not considered on clinical grounds. Earlier detection of poor prognostic signs in those without early clinical deterioration might improve outcomes in enough patients to reconsider cost effectiveness of routine repeat biopsy.

The Kidney Biopsy in Lupus Nephritis: Past, Present, and Future

Since its incorporation into clinical practice in the 1950s, the percutaneous kidney biopsy has played an important role in advancing our understanding of lupus nephritis (LN). The biopsy findings have been used to classify and subgroup LN in order to obtain an accurate diagnosis and also to inform treatment decisions and predict prognosis. Several classifications schemes have been applied clinically however despite this evolution in histopathologic classification, our ability to predict treatment response and determine prognosis remains limited. In this review we will examine the evolving role of the kidney biopsy in the management of LN, including the potentially larger role the biopsy could play in the future.

Lupus nephritis: When and how often to biopsy and what does it mean?

Renal disease is a frequent complication of SLE which can lead to significant illness and even death. Today, a baseline renal biopsy is highly recommended for all subjects with evidence of lupus nephritis. Biopsy allows the clinician to recognize and classify different forms of autoimmune lupus glomerulonephritis, and to detect other glomerular diseases with variable pathogenesis which are not directly related to autoimmune reactivity, such as lupus podocytopathy. Moreover, not only glomerular diseases, but other severe forms of renal involvement, such as tubulo-interstitial nephritis or thrombotic microangiopathy may be detected by biopsy in lupus patients. Thus, an accurate definition of the nature and severity of renal involvement is mandatory to assess the possible risk of progression and to establish an appropriate treatment. The indications to repeat biopsy are more controversial. Some physicians recommend protocol biopsies to recognize the possible transformation from one class to another one, or to identify silent progression of renal disease, others feel that good clinical monitoring is sufficient to assess prognosis and to make therapeutic decisions. At any rate, although any decision should always be taken by considering the clinical conditions of the patient, there are no doubts that repeat renal biopsy may represent a useful tool in difficult cases to evaluate the response to therapy, to modulate the intensity of treatment, and to predict the long-term renal outcome both in quiescent lupus and in flares of activity.

Do we still need renal biopsy in lupus nephritis?

The natural course of systemic lupus erythematosus (SLE) is characterized by periods of disease activity and remissions. Prolonged disease activity results in cumulative organ damage. Lupus nephritis is one of the most common and devastating manifestations of SLE. In the era of changing therapy to less toxic regimens, some authors have stated that if mycophenolate mofetil can be used for the induction and maintenance treatment in all histological classes of lupus nephritis, renal biopsy can be omitted. This article aims to answer the question of what brings the bigger risk: renal biopsy or its abandonment.

The kidney biopsy in lupus nephritis: is it still relevant?

The kidney biopsy is the standard of care for diagnosis of lupus nephritis and remains necessary to ensure accurate diagnosis and guide treatment. Repeat biopsy should be considered when therapy modifications are necessary, as in cases with incomplete or no response, or when stopping therapy for those in remission. There are several promising biomarkers of kidney disorders; however, these markers need to be validated in a prospective clinical trial before being applied clinically. Molecular analysis may provide the information presently lacking from current evaluation of kidney disorders and may better inform on prognosis and treatment considerations.

Evolution of chronic kidney disease in patients with systemic lupus erythematosus over a long-period follow-up: a single-center inception cohort study

The objective is to investigate the accrual rate and risk factors of chronic kidney disease (CKD) in an inception cohort of patients with systemic lupus erythematosus (SLE) followed at a single tertiary center. A prospectively collected database of 256 consecutive patients with SLE followed over a 25-year period was systematically interrogated for demographic, disease manifestations, co-morbidities, and outcome. Standardized SLE activity and damage scores were determined for the first and last study visits, and estimated glomerular filtration rate (eGFR; MDRD formula) was calculated at the time of diagnosis and at each year of the follow-up. CKD was defined as eGFR <60 ml/min/1.73 m(2). Results were analyzed with univariate and multivariate models and Kaplan-Meier curves, as appropriate. The cohort was predominantly female (90 %) and Jewish (91.1 %). Mean age at diagnosis was 38 ± 15.5 years, mean SLE activity score 6.4 ± 3.8, mean disease duration 8.8 ± 6.6 years, and mean damage score 0.2 ± 0.6. Seventy-five patients (30.8 %) were diagnosed with American College of Rheumatology (ACR)-defined lupus renal disease during the study period. There was a progressive decrease in eGFR over time. The prevalence of CKD was 46.7 % in patients with ACR-defined renal lupus disease and 16.4 % in those without. The hazards ratio for CKD was significantly higher in patients with lupus nephritis (LN) than without (p < 0.001). Earlier CKD was positively associated with hypertension (p = 0.01), older age at diagnosis (p = 0.01), and LN (p < 0.001), and negatively associated with hydroxychloroquine treatment (p < 0.001). The prevalence of CKD increases cumulatively in patients with SLE, also in those without overt lupus renal disease. Lupus renal disease poses a significant hazard for earlier development of CKD, and hypertension is a major risk factor for patients with and without nephritis. Antimalarial treatment is associated with renal preservation only in patients with lupus nephritis.

Renal involvement in autoimmune connective tissue diseases

Connective tissue diseases (CTDs) are a heterogeneous group of disorders that share certain clinical presentations and a disturbed immunoregulation, leading to autoantibody production. Subclinical or overt renal manifestations are frequently observed and complicate the clinical course of CTDs. Alterations of kidney function in Sjögren syndrome, systemic scleroderma (SSc), auto-immune myopathies (dermatomyositis and polymyositis), systemic lupus erythematosus (SLE), antiphospholipid syndrome nephropathy (APSN) as well as rheumatoid arthritis (RA) are frequently present and physicians should be aware of that.In SLE, renal prognosis significantly improved based on specific classification and treatment strategies adjusted to kidney biopsy findings. Patients with scleroderma renal crisis (SRC), which is usually characterized by severe hypertension, progressive decline of renal function and thrombotic microangiopathy, show a significant benefit of early angiotensin-converting-enzyme (ACE) inhibitor use in particular and strict blood pressure control in general. Treatment of the underlying autoimmune disorder or discontinuation of specific therapeutic agents improves kidney function in most patients with Sjögren syndrome, auto-immune myopathies, APSN and RA.In this review we focus on impairment of renal function in relation to underlying disease or adverse drug effects and implications on treatment decisions.

Diagnosis and treatment of lupus nephritis flares--an update

Relapses or flares of systemic lupus erythematosus (SLE) are frequent and observed in 27-66% of patients. SLE flares are defined as an increase in disease activity, in general, requiring alternative treatment or intensification of therapy. A renal flare is indicated by an increase in proteinuria and/or serum creatinine concentration, abnormal urine sediment or a reduction in creatinine clearance rate as a result of active disease. The morbidity associated with renal flares is derived from both the kidney damage due to lupus nephritis and treatment-related toxic effects. Current induction treatment protocols achieve remission in the majority of patients with lupus nephritis; however, few studies focus on treatment interventions for renal flares in these patients. The available data, however, suggest that remission can be induced again in a substantial percentage of patients experiencing a lupus nephritis flare. Lupus nephritis flares are independently associated with an increased risk of deterioration in renal function; prevention of renal flares might, therefore, also decrease long-term morbidity and mortality. Appropriate immunosuppressive maintenance therapy might lead to a decrease in the occurrence of renal and extrarenal flares in patients with SLE, and monitoring for the early detection and treatment of renal flares could improve their outcomes.

Lupus nephritis: a critical review

Lupus nephritis remains one of the most severe manifestations of systemic lupus erythematosus associated with considerable morbidity and mortality. A better understanding of the pathogenesis of lupus nephritis is an important step in identifying more targeted and less toxic therapeutic approaches. Substantial research has helped define the pathogenetic mechanisms of renal manifestations and, in particular, the complex role of type I interferons is increasingly recognized; new insights have been gained into the contribution of immune complexes containing endogenous RNA and DNA in triggering the production of type I interferons by dendritic cells via activation of endosomal toll-like receptors. At the same time, there have been considerable advances in the treatment of lupus nephritis. Corticosteroids have long been the cornerstone of therapy, and the addition of cyclophosphamide has contributed to renal function preservation in patients with severe proliferative glomerulonephritis, though at the cost of serious adverse events. More recently, in an effort to minimize drug toxicity and achieve equal effectiveness, other immunosuppressive agents, including mycophenolate mofetil, have been introduced. Herein, we provide a detailed review of the trials that established the equivalency of these agents in the induction and/or maintenance therapy of lupus nephritis, culminating in the recent publication of new treatment guidelines by the American College of Rheumatology. Although newer biologics have been approved and continue to be a focus of research, they have, for the most part, been relatively disappointing compared to the effectiveness of biologics in other autoimmune diseases. Early diagnosis and treatment are essential for renal preservation.

Collapsing glomerulopathy in 19 patients with systemic lupus erythematosus or lupus-like disease

BACKGROUND AND OBJECTIVES

Collapsing glomerulopathy is a podocytopathy with segmental or global wrinkling and collapse of capillary walls and overlying epithelial cell proliferation. Idiopathic collapsing glomerulopathy is a distinct clinicopathologic entity with significant proteinuria, poor response to immunosuppressive therapy, and rapid progression to renal failure. Collapsing glomerulopathy is associated with viral infections, autoimmune disease, and drugs. This work presents the largest group of collapsing glomerulopathy in patients with SLE.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Clinicopathological features were retrospectively studied in 19 patients with SLE (16 patients) or SLE-like (3 patients) disease with collapsing glomerulopathy.

RESULTS

Initially, 95% of patients had nephrotic syndrome with proteinuria of 3-12 g per 24 hours, creatinine levels of 0.6-9.6 mg/dl, positive lupus serologies, and normal complement levels in 63%. Segmental and/or global collapsing glomerulopathy was seen in 11%-77% of glomeruli. Tubular atrophy with focal microcystic changes and interstitial fibrosis was seen in 35% of patients. Minimal glomerular mesangial deposits were noted in 63% of patients, and extensive foot process effacement was seen in 82% of patients. Initial treatment was with pulse/oral steroids. Follow-up from 13 patients revealed that 7 patients progressed to ESRD at the time of biopsy up to 21 months later, 1 patient returned to normal creatinine (1.1 mg/dl) without proteinuria, and 5 patients had creatinine of 1.2-3.6 mg/dl with proteinuria of 0.37-4 g per 24 hours.

CONCLUSIONS

Collapsing glomerulopathy may be seen in SLE patients presenting with massive proteinuria with or without lupus nephritis, which may have prognostic significance.

Renal disease in systemic lupus erythematosus with emphasis on classification of lupus glomerulonephritis: advances and implications

CONTEXT

Systemic lupus erythematosus is an autoimmune disease with protean clinical and pathologic manifestations involving almost all organs in the body. There is a high incidence of renal involvement during the course of the disease, with varied renal pathologic lesions and diverse clinical features. A renal biopsy examined by routine light microscopy, immunofluorescence, and electron microscopy contributes toward diagnosis, prognostic information, and appropriate management.

OBJECTIVES

(1) To review the clinical and various pathologic features of renal lesions in systemic lupus erythematosus patients. (2) To introduce the International Society of Nephrology and Renal Pathology Society Classification of Lupus Glomerulonephritis.

DATA SOURCES

A literature review, illustrations with original artwork, and tabulation of clinical and pathologic data of cases obtained from the authors' renal biopsy files examined during the last 8 years were used.

CONCLUSIONS

The International Society of Nephrology/ Renal Pathology Society-sponsored Classification of Lupus Glomerulonephritis proposes standardized definitions of the various pathologic findings, describes clinically relevant lesions, incorporates prognostic parameters, and recommends a uniform way of reporting the renal biopsy findings. Lupus glomerulonephritis is divided into 6 classes primarily based on the morphologic lesions, extent and severity of the involvement, immune complex deposition, and activity and chronicity. Special emphasis is laid on describing qualitative as well as quantitative morphologic data and to include the accompanying tubulointerstitial disease and different vascular lesions, which have prognostic and therapeutic significance. This classification is intended to facilitate a higher degree of reproducibility, resulting in better patient care and more effective future clinical and translational research. Renal biopsy findings in systemic lupus erythematosus add new and independent parameters of prognostic significance to established clinical and genetic factors.

Proliferative lupus nephritis in a patient with systemic lupus erythematosus and longstanding secondary amyloid nephropathy

Secondary amyloidosis is an unusual complication of systemic lupus erythematosus (SLE). We report the case of a 60-year-old woman with SLE and secondary amyloidosis who developed class III proliferative lupus nephritis 13 years after the onset of amyloid nephropathy. The patient was treated with mycophenolate mofetil (1.5 g/day) with a significant improvement in proteinuria.

The role of kidney biopsy in the management of lupus nephritis

PURPOSE OF REVIEW

This review evaluates the role of kidney biopsy as a tool in the diagnosis, prognostication and therapeutic management of lupus nephritis. The renal biopsy is the only method available for diagnosing and classifying lupus nephritis. However, disagreements persist regarding the appropriate role of a renal biopsy in the management and identification of predictors of short and long-term outcomes.

RECENT FINDINGS

Recent modifications to the classification of lupus nephritis, the emergence of newer scoring indices, and the availability of a variety of therapeutic options predicate a reassessment of the role of the renal biopsy in the management of lupus nephritis, especially for high-risk patients.

SUMMARY

Despite some controversy, the renal biopsy has been shown to provide information over and above that provided by the clinical variables, and remains a pivotal element in optimizing therapy and the rational management of lupus nephritis.