Lupus nephritis combined with renal injury due to thrombotic thrombocytopaenic purpura-haemolytic uraemic syndrome

Association between N-acetylcysteine treatment and in-hospital mortality in adult patients with acquired thrombotic thrombocytopenic purpura: a cohort study

Acquired thrombotic thrombocytopenic purpura (aTTP) is a fatal hematologic disease. Despite the currently high standards of care, some patients who develop refractory or recurrent disease still have a poor prognosis. Although N-acetylcysteine (NAC) is recommended for the treatment of aTTP, its use in aTTP treatment is still controversial. We aimed to evaluate the association of NAC with mortality in patients with aTTP. This was a retrospective cohort study of patients with aTTP with in-hospital mortality as the primary outcome and time to platelet recovery and neurological recovery as secondary outcomes. We used multifactorial COX regression analysis to check for an association of NAC with mortality. Moreover, we performed a sensitivity analysis check the stability of our results. Finally, 89 patients with aTTP were enrolled. After adjusting for potential confounders, we found NAC to be associated with 75% lower in-hospital mortality (HR = 0.25, 95% CI = 0.1-0.64). The results of sensitivity analyses performed remained stable as the risk of in-hospital mortality in patients reduced in patients with comorbid neurological symptoms (HR = 0.23, 95% CI = 0.06-0.89). However, NAC use did not affect the time to platelet recovery (HR = 1.19, 95% CI = 0.57-2.5) or neurological recovery (HR = 0.32, 95% CI = 0.08-1.25) in patients with aTTP. NAC treatment reduces in-hospital mortality in patients with aTTP but does not shorten the time to platelet recovery or neurological recovery.

Clinicopathological features and outcomes of SLE patients with renal injury characterised by thrombotic microangiopathy

OBJECTIVES

Non-immune complex (IC)-mediated renal thrombotic microangiopathy (TMA) has been reported in patients with systemic lupus erythematosus (SLE), but most studies included patients with both renal TMA and IC-mediated lupus nephritis (LN). In this study, the clinicopathological features and outcomes of renal injury characterised by only renal TMA were retrospectively analyzed.

METHODS

Patients with glomerular and/or vascular TMA in the absence of subendothelial or epithelial immune deposits were screened from 2,332 biopsied of SLE patients. The TMA lesions were divided into glomerular, vascular or both. Acute tubular-interstitial injury was semi-quantitatively analyzed. The podocyte foot process effacement (FPE) was measured by electronic microscopy.

RESULTS

Two hundred fifty-seven (11.0%) renal biopsies revealed TMA, among which 237 biopsies showed TMA coexisting with LN, and 20 (0.9%) biopsies had only renal TMA without or with only mesangial immune deposits. All patients manifested with acute kidney injury and haematological disorders. Among them, 11 (55%) required renal replacement therapy, 12 (60%) had nephrotic syndrome and 13 (65.0%) showed microvascular haemolytic anaemia with thrombocytopenia. Seventeen (85%) biopsies revealed both glomerular TMA and vascular TMA, two had only glomerular TMA and one had vascular TMA. Eight (40%) had no glomerular immune deposits and 12 (60%) showed only mesangial immune deposits. The acute tubulointerstitial injury in patients requiring dialysis was more severe than those not needing dialysis ((43.6 ± 24.9) % vs. (21.7 ± 20.1) %, p = 0.047). FPE of podocytes was positively correlated with proteinuria (r² = 0.347, p = 0.006). All patients received high-dose methylprednisolone pulse therapy. Four patients received plasma exchange. The renal function of 11 patients requiring dialysis initially recovered after 16.0 (interquartile range [IQR] 9.0, 30.0) days of treatment. During the follow-up of 58.0 (IQR 36.0, 92.3) months, remission was achieved in 19 (95%) patients; only one patient had no response. No patient died or progressed to end-stage renal disease; six patients (30%) relapsed.

CONCLUSION

Renal TMA, usually accompanying severe renal injury, was not uncommon in SLE patients with renal disease and should be distinguished from immune complex-mediated severe classes of LN. Early intensive immunosuppressive treatment may be associated with a good long-term renal outcome. Key Points • Most previous reports of renal TMA in SLE patients were associated with severe types of immune complex-mediated lupus nephritis; • Renal TMA with glomerular pauci-immune or only mesangial immune deposits was found in SLE patients and clinically presented with severe acute renal injury but good renal outcome; • Renal TMA should be considered as a unique type of SLE-associated renal injury.

Renal microvascular lesions in lupus nephritis

Renal microvascular lesions, common in lupus nephritis (LN), are associated with long-term poor outcomes. There are mainly five pathological types of renal microvascular lesions in LN: (1) vascular immune complex deposits (ICD), (2) arteriosclerosis (AS), (3) thrombotic microangiopathy (TMA), (4) non-inflammatory necrotizing vasculopathy (NNV), and (5) true renal vasculitis (TRV). The pathogenesis of renal microvascular lesions in LN remains to be elucidated. The activation and dysfunction of endothelial cells, in addition to the contribution of immune system dysfunction, especially the immune complex-induced vascular inflammation and antiphospholipid antibody-associated thrombotic events, are key mechanisms in the development of vascular lesions in LN that need to be further investigated. Alteration of the microvascular environment produces an acute immunological response that recruits immune cells, such as T cells, monocytes, and macrophages, which induces platelet aggregation with microthrombus formation. There is also increased cytotoxicity caused by cytokines produced by immune cells in the kidney. Identifying the mechanism underlying the pathogenesis of renal microvascular lesions in LN might provide potential targets for the development of novel therapies.

Antiphospholipid Syndrome Nephropathy and Other Thrombotic Microangiopathies Among Patients With Systemic Lupus Erythematosus

Antiphospholipid syndrome (APS) and other causes of thrombotic microangiopathy (TMA) negatively impact the renal outcomes of patients with systemic lupus erythematosus (SLE) and lupus nephritis. Here we review the diagnosis and management of occlusive renal vascular lesions due to APS and other TMAs, with a focus on patients with SLE and lupus nephritis. The presence of a thrombotic event, unexplained hypertension, thrombocytopenia, or hemolytic anemia should prompt consideration for TMA syndromes. The differential diagnosis of a TMA in a patient with SLE includes APS, thrombocytopenic purpura, complement-mediated or infection-associated hemolytic uremic syndrome, drug-mediated TMA (particularly due to calcineurin inhibitor toxicity), and malignant hypertension. Treatment of APS with a documented thrombotic event focuses on anticoagulation to reduce the risk for further thrombotic events. Treatment of classic presentations of thrombocytopenic purpura and hemolytic uremic syndrome in the SLE population is the same as in patients without SLE. Treatment of APS nephropathy or TMA when it is diagnosed by biopsy with concomitant lupus nephritis presents a challenge to clinicians because there is no clear standard of care. Small and retrospective studies suggest potential benefit of complement inhibition, mammalian target of rapamycin (mTOR) inhibition, B cell depleting therapy, and plasma exchange therapy for patients with lupus nephritis and TMA, and prospective investigation of these therapies should be a research priority.

Clinical features and prognosis of patients with thrombotic thrombocytopenic purpura associated with systemic lupus erythematosus: a review of 25 cases

Objective

To report the clinical features of patients with systemic lupus erythematosus (SLE) associated with thrombotic thrombocytopenic purpura (TTP). Their diagnosis, treatment, and prognosis were also discussed.

Methods

A total of 25 TTP-SLE pediatric patients were included in this study. Their clinical symptoms, laboratory findings, disease activity, and renal biopsy were retrospectively reviewed.

Results

The median age of the patient cohort was 14 years old. Nine patients were first diagnosed with SLE, followed by the diagnosis of TTP-SLE, whereas 15 patients were diagnosed with TTP and SLE concurrently. All the 25 TTP-SLE patients had decreased platelet count and microangiopathic hemolytic anemia. Fever, rash, edema and neurological symptoms were the main clinical symptoms. Fragmentation of erythrocytes on blood smear and increased LDH were found in all patients. Nineteen patients (76%) had impaired renal function. Renal biopsy showed that most of the patients had lupus nephritis class IV (20%) and TMA (20%). 13 patients (52%) were treated with glucocorticoids in combination with immunosuppressive agent, and 10 patients (40%) were treated with plasma exchange combined with glucocorticoids plus immunosuppressive agent. One patient died due to lung infection; others had disease remission. Fifteen patients had follow-up regularly, and their conditions were stable.

Conclusion

Patients with TTP-SLE often had moderate to severe lupus disease activity. Testing of LDH level and blood smear should be performed when kidney and neurological symptoms arise in children with SLE. The use of combination therapy, glucocorticoids plus immunosuppressive agent, provided satisfactory clinical outcome. Patients with refractory TTP-SLE will also need plasma exchange therapy.

Plasma ADAMTS-13 activity in proliferative lupus nephritis: a large cohort study from China

Objectives

The aim of this study was to investigate plasma ADAMTS-13 activity in patients with proliferative lupus nephritis and to evaluate the role of clinical, laboratory and pathological features, especially the vascular lesions in lupus nephritis.

Methods

Plasma samples from 163 class III and IV lupus nephritis patients confirmed by biopsy examinations and 98 normal controls were collected. ADAMTS-13 activity was evaluated by a residual collagen binding assay. IgG autoantibodies against ADAMTS-13 were detected by ELISA using recombinant ADAMTS-13 as a solid-phase ligand. Levels of vWF were measured by ELISA. Their associations with clinical, laboratory and pathological features were further assessed.

Results

Plasma ADAMTS-13 activity in lupus nephritis patients was significantly lower than that in normal controls (84 ± 21% vs. 90 ± 13%, p = 0.005). IgG ADAMTS-13 autoantibodies were detected in only three patients. The plasma level of vWF was significantly higher in the lupus nephritis group than in normal controls (1.00 ± 0.79 vs. 0.70 ± 0.30, p = 0.025). Plasma ADAMTS-13 activity was negatively correlated with the level of serum creatinine and proteinuria ( r = –0.354, p < 0.001; r = –0.200, p = 0.011, respectively). Patients with a higher level of ADAMTS-13 activity had significantly higher levels of factor H (401.51 ± 183.01 µg/ml vs. 239.02 ± 155.45 µg/ml, p = 0.005). Plasma ADAMTS-13 activity was negatively associated with total pathological AI scores ( r = –0.326, p < 0.001), endocapillary hypercellularity ( r = –0.419, p < 0.001), cellular crescents ( r = –0.274, p < 0.001), subendothelial hyaline deposits ( r = –0.266, p = 0.001), interstitial inflammatory cell infiltration ( r = –0.304, P < 0.001), tubular atrophy ( r = –0.199, p = 0.011), acute glomerular vascular lesions ( r = –0.344, p < 0.001) and acute renal vascular lesions ( r = –0.338, p < 0.001). No association was found between level of vWF and plasma ADAMTS-13 activity ( r = 0.033, p = 0.671). Low level of ADAMTS-13 activity was a risk factor for renal outcomes ( p = 0.039, HR = 0.047, 95% CI: 0.120–1.005).

Conclusions

Decreased ADAMTS-13 activity was found in patients with proliferative lupus nephritis, and plasma ADAMTS-13 activity was closely associated with renal injury indices, especially pathological vascular scores. The role of ADAMTS-13 in the disease remains to be further investigated.

Redefining lupus nephritis: clinical implications of pathophysiologic subtypes

Systemic lupus erythematosus (SLE) is associated with a broad spectrum of clinical and immunologic manifestations, of which lupus nephritis is the most common cause of morbidity and mortality. The development of nephritis in patients with SLE involves multiple pathogenic pathways including aberrant apoptosis, autoantibody production, immune complex deposition and complement activation. The 2003 International Society of Nephrology/Renal Pathology Society (ISN/RPS) classification system for lupus nephritis was widely accepted with high intraobserver and interobserver concordance to guide therapeutic strategy and provide prognostic information. However, this classification system is not based on the underlying disease pathophysiology. Some additional lesions that contribute to disease presentation, including glomerular crescents, podocyte injury, tubulointerstitial lesions and vascular injury, should be recognized. Although outcomes for patients with lupus nephritis have improved over the past 30 years, treatment of this disease remains challenging and is best approached on the basis of the underlying pathogenesis, which is only partially represented by the various pathological phenotypes defined by the ISN/RPS classification. Here, we discuss the heterogeneous mechanisms involved in the pathogenesis of lupus nephritis and how improved understanding of underlying disease mechanisms might help guide therapeutic strategies.

Plasmapheresis Is Associated With Better Renal Outcomes in Lupus Nephritis Patients With Thrombotic Microangiopathy: A Case Series Study

The aim of this study was to evaluate the efficacy of plasmapheresis in patients with lupus nephritis-combined thrombotic microangiopathy (TMA) in a Chinese cohort.Clinical and therapeutic data of patients with lupus nephritis-combined TMA were collected retrospectively. A comparison between those with and without plasmapheresis was performed.Seventy patients with renal biopsy-proven TMA in lupus nephritis were treated with conventional combined corticosteroid and immunosuppressive agents as induction therapy, 9 of the 70 patients received additional plasmapheresis. The plasmapheresis group presented with more severe SLE and renal activity indices, including a significant higher ratio of neurologic disorder (P = 0.025), lower level of platelet count (P = 0.009), higher value of serum creatinine (P = 0.038), higher percentage of anti-cardiolipin antibodies positive (P = 0.001), and higher Systemic Lupus Erythematosus Disease Activity Index scores (P = 0.012), than that of the nonplasmapheresis group. However, the plasmapheresis group had a significant higher rate of remission and a lower ratio of treatment failure than that of the nonplasmapheresis group (P = 0.03). As the baseline data were significantly different between the 2 groups, the propensity score match was further designed to avoid retrospective bias. After re-analysis, the plasmapheresis group still had a significant higher rate of remission and a lower ratio of treatment failure than that of the nonplasmapheresis group (P = 0.018). More importantly, the plasmapheresis group had significant less composite endpoints than that of the nonplasmapheresis group (P = 0.005).Our study suggested that additional plasmapheresis on conventional induction therapy may benefit patients with lupus nephritis-combined TMA, which warrants further explorations.

Dramatic effects of eculizumab in a child with diffuse proliferative lupus nephritis resistant to conventional therapy

BACKGROUND

Treatment of systemic lupus erythematosus (SLE) with severe diffuse proliferative nephritis is often challenging, particularly in small children in whom a genetic conditioning is likely to play a role. The effectiveness of standard therapy based on glucocorticoid and immunosuppressive drugs is often unsatisfactory.

CASE

A 4 year-old girl, whose parents were first-grade cousins of Moroccan ancestry, developed SLE that progressed to severe renal involvement despite standard therapy. She had persistently undetectable serum C4 levels and very low C3 levels (<30 mg/dl), and extremely high anti-DNA titers (>1:640) that remained unmodified during 2 years of follow-up. No mutations of genes encoding for complement inhibitors were detected. Despite aggressive therapy based on prednisone, plasma exchanges, and cyclosporine, the child worsened and eventually developed features of atypical hemolytic uremic syndrome (aHUS). Treatment with eculizumab provided prompt remission of vasculitis, proteinuria, and hematuria, with normalization of renal function. Two attempts to withdraw eculizumab were followed by severe relapses and rescued by reinstating treatment. The child has been treated with eculizumab for > 17 months without relevant side effects.

CONCLUSION

C5 inhibition by eculizumab completely reversed clinical symptoms and laboratory renal signs of severe lupus nephritis. Blocking complement-system activation with the use of targeted drugs may be a new and exciting strategy to treat SLE patients unresponsive to conventional therapy.

Diverse vascular lesions in systemic lupus erythematosus and clinical implications

PURPOSE OF REVIEW

Vascular injury is one of the typical symptoms of systemic lupus erythematosus (SLE), and may play a key role in the choice of treatment strategy and prediction of prognosis. In this review, diverse vascular lesions in SLE and their clinical significance are discussed.

RECENT FINDINGS

The clinical features of vascular disease in SLE differ from organ to organ, and may be extreme with regard to renal vascular lesions. Vascular lesions in SLE may be of inflammatory or thrombotic origin, and immune system dysfunction is considered to be a predominant feature. Numerous lines of evidence suggest that the activation and injury of endothelial cells might play a key role in the pathogenesis.

SUMMARY

Vascular lesions in SLE are mediated by a complex interaction between the immune system and other contributing factors. Different therapies developed for vascular lesions, both immunosuppressive and nonimmunosuppressive, should be selected based on the different clinical and pathological characteristics, and our future understanding of the different mechanisms involved.

Clinical and renal biopsy findings predicting outcome in renal thrombotic microangiopathy: a large cohort study from a single institute in China

Objective. The current study aimed to investigate the spectrum of etiologies and associated disorders of renal biopsy-proven thrombotic microangiopathy (TMA) patients. Methods. The clinical, laboratory, and renal histopathological data of patients with renal TMA from 2000 to 2012 in our institute were collected and reviewed. Results. One hundred and nine TMA patients were enrolled in this study. The mean age was 34.0 ± 11.1 years. Seventy patients (64.2%) were male and thirty-nine patients (35.8%) were female. There were eight patients (7.3%) with hemolytic uremic syndrome (HUS). Sixty-one patients (56.0%) were secondary to malignant hypertension. Fourteen patients (12.8%) were pregnancy-associated TMA. Other associated disorders included 17 patients with connective tissue disorders, 2 patients with hematopoietic stem cell transplantation, 4 patients with Castleman's disease, 1 patient with cryoglobulinemia, and 2 patients with glomerulopathy. During followup, 8 patients died due to severe infection, 17 patients had doubling of serum creatinine, and 44 had end-stage renal disease. In multivariate analysis, male, elevated serum creatinine, and decreased hemoglobin were independently associated with poor renal outcomes. Conclusions. Renal TMA changes consisted of different disorders with various etiologies. aHUS, pregnancy-associated TMA, and malignant hypertension accounted for the majority of patients in our cohort.

Clinical features and prognostic factors of thrombotic thrombocytopenic purpura associated with systemic lupus erythematosus: a literature review of 105 cases from 1999 to 2011

This study aims to review clinical features, treatments, and prognostic factors of thrombotic thrombocytopenic purpura (TTP) associated with systemic lupus erythematosus patients (sTTP). The case reports of sTTP published in world literature from 1999 to 2011 were collected, and 105 cases were divided into death group and survival group. The epidemiologic characteristics, clinical manifestations, laboratory examinations, treatments, and prognostic factors were analyzed. We found that coexistence of renal and neurological impairments were significantly frequent in the death group (100 %) than in the survival group (56.5 %) (P = 0.002). Type IV was predominant in 57.7 % of renal pathological damage, followed by type V (11.5 %), type II (5.8 %), and thrombotic microangiopathy (TMA) (5.8 %). TMA appeared more frequently (50 %) in the death group than in the survival group (6.25 %) (P = 0.042). End-stage renal disease occurred in nine cases with type IV in five (55.6 %), type TMA in one (11.1 %), and unspecified in three cases (33.3 %). Of 32 cases, 40.6 % showed severe ADAMTS13 deficiency and returned to normal or mildly deficient after remission. The total mortality rate of sTTP was 12.4 % and the mortality rate of patients with infection (27.3 %) was significantly higher than those without infection (8.4 %) (P = 0.028). Plasma exchange and glucocorticoids were administrated in over 80 % of cases with 65.7 % remission rate, while additional cytotoxics or rituximab was mostly used in refractory sTTP and achieved over 90 % of remission rate. Above all, coexistence of renal and neurological impairments, infection, and renal damage with type IV or TMA might denote a poor prognosis of sTTP.

Kidney-limited thrombotic microangiopathy in patients with SLE treated with romiplostim

We present the case of a 19 year-old Caucasian female with history of systemic lupus erythematosus (SLE) and normal baseline kidney function who developed severe acute renal failure following treatment of thrombocytopenia with the thrombopoietic agent romiplostim. Percutaneous kidney biopsy revealed thrombotic microangiopathy (TMA) without immune complex lupus glomerulonephritis. We discuss pathogenesis and differential diagnosis of TMA in patients with SLE and raise concerns regarding the use of thrombopoietic agents in such patients. Based on favorable long-term outcome in our case aggressive treatment and in particular prolonged use of plasma exchange in these patients are advocated.

The spectrum of renal thrombotic microangiopathy in lupus nephritis

INTRODUCTION

Among various lupus renal vascular changes, thrombotic microangiopathy (TMA) presented with the most severe clinical manifestations and high mortality. The pathogenesis of TMA in systemic lupus erythematosus (SLE) was complicated. The aim of this study was to assess clinical manifestations, laboratory characteristics, pathological features and risk factors for clinical outcomes of lupus nephritis patients co-existing with renal TMA in a large cohort in China.

METHODS

Clinical and renal histopathological data of 148 patients with biopsy-proven lupus nephritis were retrospectively analyzed. Serum complement factor H, A Disintegrin and Metalloprotease with Thrombospondin type I repeats 13 (ADAMTS-13) activity, antiphospholipid antibodies and C4d deposition on renal vessels were further detected and analyzed.

RESULTS

In the 148 patients with lupus nephritis, 36 patients were diagnosed as co-existing with renal TMA based on pathological diagnosis. Among the 36 TMA patients, their clinical diagnoses of renal TMA were as followings: 2 patients combining with thrombotic thrombocytopenic purpura-hemolytic uremic syndrome, 2 patients combining with anti-phospholipid syndrome, 2 patients with malignant hypertension, 1 patient with scleroderma and the other 29 patients presenting with isolated renal TMA. Compared with the non-renal TMA group, patients with renal TMA had significantly higher urine protein (7.09±4.64 vs. 4.75±3.13 g/24h, P=0.007) and serum creatinine (159, 86 to 215 vs. 81, 68 to 112 μmol/l, P<0.001), higher scores of total activity indices (AI) (P<0.001), endocapillary hypercellularity (P<0.001), subendothelial hyaline deposits (P=0.003), interstitial inflammation (P=0.005), glomerular leukocyte infiltration (P=0.006), total chronicity indices (CI) (P=0.033), tubular atrophy (P=0.004) and interstitial fibrosis (P=0.018). Patients with renal TMA presented with poorer renal outcome (P=0.005) compared with the non-TMA group. Renal TMA (hazard ratio (HR): 2.772, 95% confidence interval: 1.009 to 7.617, P=0.048) was an independent risk factor for renal outcome in patients with lupus nephritis. The renal outcome was poorer for those with both C4d deposition and decreased serum complement factor H in the TMA group (P=0.007).

CONCLUSIONS

There were various causes of renal TMA in lupus nephritis. Complement over-activation via both classical and alternative pathways might play an important role in the pathogenesis of renal TMA in lupus nephritis.

Systemic sclerosis with thrombotic thrombocytopenia purpura and malignant hypertension

Thrombotic thrombocytopenia purpura (TTP) is a rare clinical syndrome characterized by microangiopathic hemolytic anemia (MAHA), thrombocytopenia, neurologic symptoms, acute renal impairment, and fever. It has been seldom reported in systemic sclerosis (SSc). Systemic renal crisis is an infrequent complication of SSc, and is characterized by new onset malignant hypertension, rapidly progressive oliguric renal failure, and MAHA. In this study, we present a case of SSc of 1 month duration, with TTP accompanied by new onset malignant hypertension. The patient responded to plasmapheresis but still died of septic shock.

Acute kidney injury in Chinese patients with lupus nephritis: a large cohort study from a single center

OBJECTIVE

In this study we assess clinicopathologic characteristics, treatment and prognosis of acute kidney injury (AKI) in a large cohort of Chinese patients with lupus nephritis.

METHODS

The clinical, laboratory, renal histopathology, treatment and outcome data were retrospectively collected and compared between lupus nephritis patients with and without AKI. The impact of AKI on renal outcome was evaluated.

RESULTS

Among 322 patients with renal biopsy-proven lupus nephritis, 66 (20.5%) were identified as AKI. Male predominance was observed in patients with AKI (p < 0.001). In comparison with the non-AKI group, patients with AKI had significantly higher proportions of serositis (p < 0.001), neurologic disorder (p = 0.026), anemia (p < 0.001), thrombocytopenia (p = 0.013) and nephrotic syndrome (p = 0.011), but significant lower serum C3 (p < 0.001). The Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores, renal pathological activity indices and chronicity indices were significantly higher in the AKI group (p < 0.001 in all cases). Regarding outcome, the AKI group had a significantly poorer renal outcome compared with non-AKI group (p < 0.001). In the AKI group, patients with crescentic glomerulonephritis and thrombotic microangiopathy had the worst renal outcome. AKI was an independent risk factor for renal outcome (hazard ratio [HR] = 5.819, 95% confidence interval 2.411-14.044, p < 0.001).

CONCLUSIONS

AKI is common in lupus nephritis and is an independent risk factor for renal outcome.

Clinical characteristics and prognosis of diffuse proliferative lupus nephritis with thrombotic microangiopathy

We retrospectively analyzed the clinicopathologic characteristics and prognosis of 33 patients with diffuse proliferative lupus nephritis (class IV LN) complicated with thrombotic microangiopathy (TMA). Eighty-one percent of patients had renal dysfunction (mean Scr 3.1 ± 2.0 mg/dl), among whom 42.4% needed acute hemodialysis. Nephrotic proteinuria, gross hematuria and hypertension were presented in 57.6%, 24.2% and 93.9% of the patients. Microangiopathic hemolytic anemia, serum anti-dsDNA and anticardiolipin antibodies were found in 60.6%, 75.8% and 33.3% of the patients. Renal biopsy showed IV-G in 75.8%, class IV with class V in 21.2%, and IV-S in 1.23% of the patients. Glomerular segmental necrosis, microthrombi, crescents and arteriolar thrombosis were found in 51.5%, 69.7%, 60.6% and 60.7% of the patients, respectively. The follow up was 1 to 101 months (median 13 months). Only 50% of patients showed response to treatment. Three patients died, 10 developed end-stage renal failure (ESRF). The 5-year patient and renal survival rate was 69.2% and 46.7%, respectively. Major risks for ESRF included: a need for acute dialysis on admission, no response to the treatment and high renal chronic index. The results showed that class IV lupus nephritis with TMA has high mortality and low renal survival.

Rapidly progressive lupus nephritis and concomitant thrombotic microangiopathy

Although uncommon, thrombotic microangiopathy (TMA) is one of the most serious complications in patients with systemic lupus erythematosus. A 30-year-old black woman admitted to our hospital because of fever, fatigue, 'dark' urine and rapidly progressive renal failure was found to have systemic lupus erythematous and atypical hemolytic uremic syndrome. Kidney biopsy showed WHO class IV lupus nephritis with crescents and TMA. Hemodialysis was initiated for worsening renal failure. The patient was treated with corticosteroids, monthly pulse intravenous Cyclophosphamide, plasmapheresis and Rituximab on a weekly basis for 4 weeks. The patient's blood pressure was aggressively controlled using antihypertensive agents. Despite this extensive therapy, she remained dialysis dependent although hematological parameters returned to normal values.