Assessment of epidemiology and outcomes of adult patients with kidney-limited thrombotic microangiopathies.

Thrombotic microangiopathies (TMA) are usually associated with hematological features (RH-TMA). The epidemiology of TMA limited to kidneys (RL-TMA) is unclear Therefore, patients with TMA and native kidney biopsies were identified during 2009-2022 in 20 French hospitals and results evaluated. RL-TMA was present in 341/757 (45%) patients and associated with lower creatinine levels (median 184 vs 346 µmol/L) than RH-TMA. RL-TMA resulted from virtually all identified causes, more frequently from anti-VEGF treatment and hematological malignancies but less frequently from shigatoxin-associated hemolytic uremic syndrome (HUS), systemic sclerosis, gemcitabine and bacterial infection, and even less frequently when three or more causes/triggers were combined (RL-TMA: 5%; RH-TMA: 12%). RL-TMA was associated with significantly lower major cardiovascular events (10% vs 20%), kidney replacement therapy (23% vs 43%) and death (12% vs 20%) than RH-TMA during follow-up (median 28 months). Atypical HUS (aHUS) was found in 326 patients (RL-TMA: 43%, RH-TMA: 44%). Among the 69 patients with proven complement-mediated aHUS, eculizumab (anti-C5 therapy) was used in 43 (62%) (RL-TMA: 35%; RH-TMA: 71%). Among the 257 other patients with aHUS, including 51% with RL-TMA, eculizumab was used in 29 but with unclear effects of this treatment. Thus, RL-TMA represents a very high proportion of patients with TMA and results from virtually all known causes of TMA and includes 25% of patients with complement-mediated aHUS. Adverse outcomes of RL-TMA are lower compared to RH-TMA but remain significant. Anti-C5 therapy was rarely used in RL-TMA, even in proven complement-mediated aHUS, and its effects remain to be assessed.

The estimated prevalence of antiphospholipid antibodies and criteria-antiphospholipid syndrome in subjects with renal thrombotic microangiopathy.

BACKGROUND: While the prevalence of antiphospholipid antibodies (aPL) in venous and arterial thrombotic events had already been estimated by previous studies, the prevalence of aPL in subjects with Thrombotic Microangiopathy (TMA) is still not fully elucidated. Thus, we conducted a systematic review to estimate the frequency of aPL in subjects with biopsy-proven renal TMA. METHODS: We conducted in the PubMed database a search for English-language studies investigating the presence of aPL in subjects with biopsy-proven renal TMA from January 1985 to December 2022. Keywords used in the search included: 'antiphospholipid syndrome', 'antiphospholipid antibodies' and 'thrombotic microangiopathy'. Cohorts of HUS patients were excluded due to the risk of over-estimating the prevalence of aPL in these populations. The median frequency for positive aPL including anticardiolipin antibodies (aCL), antibodies against ß2-glycoprotein-I (anti-ß2GPI) and lupus anticoagulant (LA) was then calculated. RESULTS: 522 articles were identified through the literature search. Six studies, assessing the prevalence of aPL in 211 subjects with renal TMA, were retrieved. The overall aPL prevalence was estimated as 24.4% (range 22-56). The estimated prevalence of aCL (IgG/IgM), anti-ß2GPI, (IgG/IgM) and LA was 4.0% (range 3-27), 4.0% (range 3-16) and 18.9% (range 13-25), respectively. APS was diagnosed in 16.3% (range 11-29) of the patients. Of note, a high level of heterogeneity was observed when comparing the reported aPL profiles for each study. CONCLUSIONS: This comprehensive systematic analysis of studies investigating the prevalence of aPL in renal TMA showed that, despite the high heterogeneity of the included studies, aPL are present in about one case out of four renal-TMA cases.

Frequency and characteristics of chemotherapy-associated thrombotic microangiopathy: Analysis from a large pharmacovigilance database.

We used the information component (IC), a disproportionate Bayesian analysis comparing the number of observed versus expected adverse drug reactions, to determine the potential association between anti-neoplastic agents and thrombotic microangiopathy (TMA). The IC025 indicates the lower end of 95% of IC, in which a value >0 suggests a disproportionality signal between the drug of interest and the adverse drug reaction. Carfilzomib had the highest IC025 for TMA among all studied chemotherapies followed by gemcitabine, mitomycin, bevacizumab, and bortezomib.

Thrombotic microangiopathies after kidney transplantation in modern era: nosology based on chronology.

BACKGROUND: Thrombotic microangiopathies (TMAs) are rare but can be severe in kidney transplant. recipients (KTR). METHODS: We analysed the epidemiology of adjudicated TMA in consecutive KTR during the. 2009-2021 period. RESULTS: TMA was found in 77/1644 (4.7%) KTR. Early TMA (n = 24/77 (31.2%); 1.5% of all KTR) occurred during the first two weeks ((median, IQR) 3 [1-8] days). Triggers included acute antibody-mediated rejection (ABMR, n = 4) and bacterial infections (n = 6). Graft survival (GS) was 100% and recurrence rate (RR) was 8%. Unexpected TMA (n = 31/77 (40.2%); 1.5/1000 patient-years) occurred anytime during follow-up (3.0 (0.5-6.2) years). Triggers included infections (EBV/CMV: n = 10; bacterial: n = 6) and chronic active ABMR (n = 5). GS was 81% and RR was 16%. Graft-failure associated TMA (n = 22/77 (28.6%); 2.2% of graft losses) occurred after 8.8 (4.9-15.5) years). Triggers included acute (n = 4) or chronic active (n = 14) ABMR, infections (viral: n = 6; bacterial: n = 5) and cancer (n = 6). 15 patients underwent transplantectomy. RR was 27%. Atypical (n = 6) and typical (n = 2) haemolytic and uremic syndrome, and isolated CNI toxicity (n = 4) were rare. Two-third of biopsies presented TMA features. CONCLUSIONS: TMA are mostly due to ABMR and infections; causes of TMA are frequently combined. Management often is heterogenous. Our nosology based on TMA timing identifies situations with distinct incidence, causes and prognosis.

Potential factors for and the prognostic impact of ascites after allogeneic hematopoietic stem cell transplantation.

Ascites is sometimes detected after allogeneic hematopoietic stem cell transplantation (allo-HSCT); however, since limited information is currently available, its clinical meaning remains unclear. Therefore, we herein examined potential factors for and the impact of ascites on the prognosis of patients after allo-HSCT at our institutes. Fifty-eight patients developed ascites within 90 days of allo-HSCT (small in 34 (16%), moderate-large in 24 (11%)). A multivariate analysis identified veno-occlusive disease/sinusoidal obstruction syndrome (p = 0.01) and myeloablative conditioning (p = 0.01) as significant potential factors for the development of small ascites. Thrombotic microangiopathy (TMA) (p < 0.01) was a significant potential factor for moderate-large ascites. The incidence of both small and moderate-large ascites correlated with lower overall survival (p = 0.03 for small ascites and p < 0.01 for moderate-large ascites) and higher non-relapse mortality rates (p = 0.03 for small ascites and p < 0.01 for moderate-large ascites). Lower OS and higher NRM rates correlated with the incidence of both small and moderate-large ascites. Further investigation is warranted to establish whether the clinical sign of ascites improves the diagnostic quality of TMA in a large-scale study.

Prospective Clinical and Biomarker Validation of the American Society for Transplantation and Cellular Therapy Consensus Definition for Transplantation-Associated Thrombotic Microangiopathy.

Transplantation-associated thrombotic microangiography (TA-TMA) is a disorder that causes severe complications after allogeneic hematopoietic cell transplantation (allo-HCT). Diagnosing TA-TMA is challenging because of the lack of standardized criteria. In this study, we aimed to evaluate the new TA-TMA consensus definition from the American Society for Transplantation and Cellular Therapy (ASTCT) panel as part of an ongoing prospective pediatric cohort study, and also to compare the impact and outcomes of using the current definition of clinical TMA (cTMA) versus the new consensus definition. We included patients age 0 to 18 years who underwent their first allo-HCT between May 2021 and January 2023 at Texas Children's Hospital. We compared the incidence, biomarkers, and outcomes of TA-TMA applying the previous and recently proposed screening algorithms and definitions. Whereas use of the classic microangiopathic hemolytic anemia (MAHA)-based cTMA definition led to an incidence of 12.7% by day 100 post-transplantation, the ASTCT-HR definition doubled the incidence to 28.5% by day 100. In contrast to patients with a concordant diagnosis (+/+), who had significantly worse post-transplantation survival, those reclassified as TA-TMA only by the new definition (-/+) had a significantly different prognosis (100% survival at day 100) despite the lack of TMA-directed therapy. Furthermore, biomarkers of the terminal and alternative complement pathways (sC5b9 and Ba, respectively) were significantly elevated compared with non-TMA patients around day 15 in the concordant group (+/+) but not in the discordant group (-/+). The recently proposed ASTCT consensus TA-TMA diagnosis is more sensitive and allows earlier recognition of manifestation that requires closer clinical monitoring but risks overdiagnosis and overtreatment. We recommend additional prospective validation.

Long-term survival and renal outcomes of thrombotic microangiopathy in pregnancy: A retrospective cohort study.

OBJECTIVE: Thrombotic microangiopathy (TMA) in pregnancy can rapidly progress, leading to severe morbidities. This study aimed to compare baseline demographics and clinical outcomes between pregnant women with and without TMA. METHODS: Using the National Health Insurance Research Database, 207 patients with pregnancy-related TMA from January 1, 2006 to December 31, 2015 were enrolled. Their data were compared with a 1:4 propensity score-matched cohort of 828 pregnant women without TMA to evaluate mortality and end-stage renal disease (ESRD) risks. Cox proportional hazards models were used to estimate the adjusted hazard ratio and 95% confidence intervals. RESULTS: A total of 1035 participants were included. The risks of mortality and ESRD were 4.46 and 5.97 times higher for the TMA cohort, respectively. Subgroup analysis revealed higher mortality and ESRD risks in patients with TMA aged >40 years with a history of hypertension, stroke, cancer, concomitant stroke, malignant hypertension, or gastroenterocolitis than in the matched cohort. CONCLUSION: Pregnant patients with TMA, especially those older and with comorbidities and organ involvement, faced increased mortality and ESRD risks. Physicians should collaborate with obstetricians throughout the prenatal and postpartum periods for these patients.

Risk factors for transplant-associated thrombotic microangiopathy (TA-TMA): a systematic review and meta-analysis.

INTRODUCTION: Transplant-associated thrombotic microangiopathy (TA-TMA) is a severe hematopoietic stem cell transplantation complication with high mortality and a poor patient prognosis. The pathogenesis of TA-TMA is not yet clear. In previous studies, the conclusions of different centers remain controversial. We conducted a systematic review and meta-analysis of nine selected risk factors that might be associated with the onset of TA-TMA. MATERIALS AND METHODS: PubMed databases were searched from their inception up to 15 September 2021, for relevant studies. The articles included unprocessed data related to one or more of the risk factors discussed in this meta-analysis, including recipient gender, donor type, graft source, pretreatment, infection, aGVHD, diagnosis, total body irradiation (TBI), and CMV infection. The outcome is the incidence rate (IR) of TA-TMA. RESULTS AND CONCLUSIONS: According to the sixteen articles included, risk factors included in this Meta-analysis included gender, unrelated donor source (95% CI: 1.29-2.01), graft source from peripheral blood stem cell (PBSC)(95% CI: 0.48-0.97), RIC/NMA, class II-IV aGVHD (95% CI: 2.22-4.78), nonmalignant disease, TBI. However, inconsistent diagnostic criteria for TA-TMA and the limited number of studies have an impact on the results of the study. More prospective cohort studies and More accurate diagnostic criteria are needed.

Epidemiology and outcomes of pediatric transplant-associated thrombotic microangiopathy in Hong Kong.

BACKGROUND: Transplant-associated thrombotic microangiopathy (TA-TMA) is an under-recognized yet potentially devastating complication of hematopoietic stem cell transplantation (HSCT) which had increased awareness in recent years. This report summarizes the demographics and outcomes of pediatric TA-TMA in Hong Kong. METHODS: All patients aged below 18 years who underwent HSCT in the Hong Kong Children's Hospital and were diagnosed to have TA-TMA during the 2-year period from April 1, 2019 to March 31, 2021 were included. RESULTS: A total of 73 transplants (51 allogeneic and 22 autologous) in 63 patients had been performed. Six patients (four males and two females) developed TA-TMA at a median duration of 2.5 months post-HSCT. The incidence rate was 9.52%. Of the six TA-TMA patients, five underwent allogenic one underwent autologous HSCT, respectively. Three of them were histologically proven. All four patients with cyclosporine had stopped the drug once TA-TMA was suspected. Median six doses of eculizumab were administered to five out of six patients. Three patients died (two due to fungal infection and one due to acute-on-chronic renal failure) within 3 months upon diagnosis of TA-TMA. Among three survivors, two stabilized with mild stage 2 chronic kidney disease (CKD) while the other suffered from stage 5 end-stage CKD requiring lifelong dialysis. CONCLUSION: In conclusion, recognition and diagnosis of TA-TMA are challenging. Early recognition and prompt administration of complement blockage with eculizumab may be beneficial in selected cases. Further prospective research studies are recommended to improve the management and outcomes of TA-TMA.

Lombardy diagnostic and therapeutic network of thrombotic microangiopathy.

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare, life-threatening thrombotic microangiopathy (TMA) requiring urgent treatment. Standardization of its diagnosis and optimal management is challenging. This study aimed to evaluate the role of centralized, rapid testing of ADAMTS13 in patients experiencing acute TMAs requiring plasma-exchange (PEX) and to estimate the incidence of TTP in a large Italian Region. METHODS: We perfomed a cohort study in the frame of the project "Set-up of a Lombardy network for the study and treatment of patients undergoing apheresis", including 11 transfusion centers in the Region. Consecutive patients referred from 2014 to 2016 with acute TMAs requiring PEX were enrolled. Centralized ADAMTS13 activity testing was performed at the Milan Hemophilia and Thrombosis Center within 24 h. RESULTS: Forty-three TMA patients (44 events) were enrolled, of whom 35 (81%) had severe ADAMTS13 deficiency. Patients with severe ADAMTS13 deficiency were younger, mainly women, with a higher prevalence of autoimmune disorders and a lower prevalence of cancer. Clinical and laboratory characteristics of patients with and without severe ADAMTS13 deficiency largely overlapped, with a lower platelet count being the only baseline marker that significantly differed between the two patient groups (ADAMTS13 activity < 10% vs ≥ 10%: median difference of -27 × 109/l, 95% CI - 37 to - 3). PEX treatment was initiated in all patients, but soon discontinued in cases without severe ADAMTS13 deficiency. In this group, the mortality rate was higher and no episode exacerbations or relapses within 6 months occured. The estimated average annual incidence of acute acquired TTP events was 1.17 [0.78-1.55] per million people. CONCLUSIONS: Severe ADAMTS13 deficiency distinguished two groups of patients with largely overlapping clinical features but different treatment and disease course. This study provides a feasible model implemented in a large Italian region for the practical clinical approach to TMAs and underlines the importance of urgent ADAMTS13 activity testing for an accurate differential diagnosis and therapeutic approach.

Carfilzomib-induced thrombotic microangiopathy is underestimated in clinical practice: A report of five patients and literature review.

Carfilzomib (Cfz) is widely used to treat multiple myeloma. However, real-world data of the incidence of thrombotic microangiopathy (TMA) caused by Cfz is inconsistent (<1-5%). We evaluated 96 consecutive patients who received Cfz to evaluate the incidence of TMA in clinical practice. TMA developed in five patients (5.2%) who were mainly receiving high-dose Cfz (≥56 mg/m2). Based on a literature review, precaution should be taken for Cfz-induced TMA in male patients receiving high-dose Cfz irrespective of the combination therapy, Cfz administration period, and complement level. In conclusion, Cfz-induced TMA might be underestimated in clinical practice, and early intervention should be considered.

Acute graft-versus-host disease increase risk and accuracy in prediction model of transplantation-associated thrombotic microangiopathy in patients with myelodysplastic syndrome.

Allogeneic hematopoietic stem cell transplantation is the only curative therapy for patients with myelodysplastic syndrome. Transplantation-associated thrombotic microangiopathy (TA-TMA) remains a cause of death after transplantation. This study assessed the risk factors of TA-TMA and established a prediction model for this complication. We launched a real-world study from 303 MDS patients after allo-HSCT from Dec 1, 2007, to Jun 1, 2018. Logistic regression was used to analyze risk factors and to establish a nomogram. The accuracy of the model was assessed by C-index and calibration curve. TA-TMA class was associated with an over twofold increase in the risk of death (HR 2.66, 95% CI 1.39-5.09, p = 0.003). Stage III or IV acute graft-versus-host disease (aGVHD) (OR: 6.17, 95% CI: 2.19-17.18, p < 0.001) and occurrence time of aGVHD were the risk factors for TA-TMA. Next, we put these two variants and the other three variants into the prediction model via multivariate Lasso regression. In order to quantify the contribution of each factor, a nomogram was generated and displayed (C index of 0.783). TA-TMA predicts worsened outcomes of overall survival. A cross-validated multivariate score including aGVHD occurrence showed excellent concordance and efficacy of predicting TA-TMA in HSCT patients.

Incidence and Risk Factors of Transplantation-Associated Thrombotic Microangiopathy: A Systematic Review and Meta-Analysis.

Transplantation-associated thrombotic microangiopathy (TA-TMA) is an increasingly recognized post-transplantation complication, yet the overall incidence of the disease remains under debate. To determine the pooled incidence of TA-TMA in a systematic review of literature and to identify consistent risk factors. We performed a systematic review using the MEDLINE, Embase, and CENTRAL databases to identify cohort studies that reported incidence of and risk factors for TA-TMA from 2004 to 2020. We conducted a meta-analysis of proportion to estimate the pooled incidence of TA-TMA using a random-effects model. We assessed moderators of heterogeneity through subgroup analysis, risk of bias through ROBINS-I, and publication bias through funnel plot. Among 21 cohort studies with a total of 36,163 adult and pediatric patients who underwent allogeneic transplantation, the pooled incidence of TA-TMA was 12% (95% confidence interval, 9% to 16%). The diagnostic criteria used to define the disease was the most significant contributor identified to the high interstudy heterogeneity (I2 = 98%). Studies using provider/clinician diagnosis instead of laboratory diagnosis reported the lowest incidence, at 3%. The most salient risk factor for TA-TMA reported in 14 studies was preceding acute graft-versus-host disease (GVHD). Other risk predictors described in 5 or more studies included preceding infection, prior transplantation, mismatched donor, and myeloablative conditioning. With a pooled incidence at 12% among a significantly heterogeneous population, TA-TMA is an important but relatively uncommon post-transplantation complication. Given the divergence between reported laboratory-based and provider-based incidence, as well as the multitude of risk factors beyond acute GVHD, future studies should focus on risk-stratifying the subset of TA-TMA patients who would benefit from therapeutic intervention.

Acute GVHD, BK virus hemorrhagic cystitis and age are risk factors for transplant-associated thrombotic microangiopathy in adults.

Hematopoietic cell transplantation-associated thrombotic microangiopathy (TMA) is a complication associated with higher nonrelapse mortality (NRM) in patients who undergo allogeneic transplant (HCT). Current classification criteria are not generally agreed on or validated, and the presence of confounding factors after transplant contribute to underdiagnosis or delayed diagnosis of TMA. We studied risk factors, incidence, and biomarkers of TMA in 119 adult allogeneic HCT recipients. Twenty-seven patients developed a clinically actionable phenotype of TMA (CA-TMA) and the incidence of CA-TMA was 22% by day 180. Among the 27 patients who developed CA-TMA, 10 developed it before the onset of acute graft-versus-host disease (aGVHD), and 17 patients developed it after the onset of aGVHD. We report for the first time that age >50 years, BK hemorrhagic cystitis, and other viral infections (CMV, HHV-6, or adenovirus) are risk factors for adult CA-TMA. Even after adjustment for aGVHD, CA-TMA was independently associated with significantly higher NRM. These data illustrate relationships between CA-TMA and aGVHD, describe new risk factors for CA-TMA and emphasizes the need to develop validated set of criteria for timely diagnosis.

Acute Kidney Injury in Obstetric Patients.

Obstetric-related acute kidney injury (obstetric AKI) is an important and complex public health problem; its early recognition and proper treatment are key in preventing maternal and fetal adverse outcomes. While the incidence of obstetric AKI has drastically declined in some developing countries due to reduction of sepsis-related causes, the opposite has been observed in other developed nations in the last decade due to advanced maternal age and the presence of comorbidities. The diagnosis of obstetric AKI has been made difficult by the physiologic decrease in serum creatinine of pregnancy as well as the absence of a uniform definition for AKI in this population. The most common causes of obstetric AKI include pre-renal etiologies such as hyperemesis gravidarum and post-abortal sepsis, intra-renal causes which comprise the thrombotic microangiopathies (preeclampsia/HELLP, thrombotic thrombocytopenic purpura, pregnancy associated-hemolytic uremic syndrome, lupus nephritis), and post-renal causes due to obstruction from kidney stones or iatrogenic injuries during delivery. A kidney biopsy is rarely required and should be reserved for cases where the diagnosis will change management, preferably before the third trimester. A multidisciplinary approach with the maternal-fetal-medicine specialist and nephrologist, along with the intensivist and hematologist may be needed. In this review, we will present the latest updates on the global epidemiology, focus on the most challenging thrombotic microangiopathy diagnoses, summarize treatment recommendations, and delineate the ongoing challenges as well as novel strategies to tackle this public health burden which does not seem to be disappearing.

Thrombotic Microangiopathy Increases the Risk of Chronic Kidney Disease but Not Overall Mortality in Long-term Transplant Survivors.

Thrombotic microangiopathy (TMA) after allogeneic hematopoietic cell transplant (HCT) is associated with acute kidney injury (AKI) and increased mortality. The impact of TMA on chronic kidney disease (CKD) and long-term mortality among HCT survivors has not been fully examined. To assess the risk of CKD and mortality in HCT survivors with and without history of TMA, we conducted a retrospective cohort study among adult allogeneic HCT recipients who survived to at least 1 year post-transplantation. We examined the association between the history of TMA within 1 year and the onset of CKD longitudinally for 5 years with generalized estimating equation (GEE) while adjusting for other key confounders. CKD was defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 using the CKD-EPI formula with outpatient creatinine values collected during the annual long-term follow-up unit follow-up visits. Kaplan Meier curves landmarked at 1 year were used for survival analyses. Among 2091 adult patients who underwent allogeneic HCT, we identified 1151 patients who survived at least 1 year and had available long-term follow-up data. Among them, 57 patients developed TMA within 1 year and 1094 did not have TMA. There was no pretransplantation baseline difference in eGFR between groups. After adjusting for confounders, history of TMA was associated with an odds ratio of 2.83 (95% confidence interval 1.33-6.03) for CKD development over 5 years after transplantation. The conditional 5-year survival was 78% in the TMA survivors and 80% in the non-TMA survivors (log rank P = .122). HCT survivors with a history of TMA had increased risk of CKD development. Although TMA was associated with high risk of mortality within 1 year after transplantation, long-term survival was comparable with non-TMA survivors. Future therapeutic interventions should focus on not only short-term mortality outcomes, but also short- and long-term kidney outcomes for HCT patients with TMA.

Transplant-associated thrombotic microangiopathy in pediatric patients: pre-HSCT risk stratification and prophylaxis.

Transplant-associated thrombotic microangiopathy (TA-TMA) is an endothelial injury syndrome that complicates hematopoietic stem cell transplant (HSCT). Morbidity and mortality from TA-TMA remain high, making prevention critical. We describe our retrospective single-center experience of TA-TMA after pediatric allogeneic HSCT and present a novel pre-HSCT risk-stratification system and prophylaxis regimen. From January 2012 through October 2019, 257 patients underwent 292 allogeneic HSCTs. Prospective risk stratification was introduced in December 2016. High-risk (HR) patients were treated with combination prophylaxis with eicosapentaenoic acid and N-acetylcysteine. The 1-year cumulative incidence of TA-TMA was 6.3% (95% confidence interval [CI], 3.2-9.4). Age ≥10 years, myeloablative conditioning with total body irradiation, HLA mismatch, diagnosis of severe aplastic anemia or malignancy, prior calcineurin inhibitor exposure, and recipient cytomegalovirus seropositivity were found to be pre-HSCT risk factors for development of TA-TMA. Before routine prophylaxis, TA-TMA rates were significantly different between the HR and standard-risk groups, at 28.2% (95% CI, 0-12.7) vs 3.2% (0.1-6.3), respectively (P < .001). After introduction of prophylaxis, the 1-year cumulative incidence of TA-TMA in the HR group decreased to 4.5% (95% CI, 0-13.1; P = .062, compared with the incidence before prophylaxis). Multicenter pediatric studies are needed to validate these risk criteria and to confirm the efficacy of the prophylactic regimen.

Association of antiphospholipid antibodies with clinical activity and renal pathological activity in patients with lupus nephritis.

OBJECTIVES: This study aimed to investigate the association of antiphospholipid antibodies (aPL) with clinical activity and renal pathological activity in patients with lupus nephritis (LN). METHODS: Levels of anticardiolipin () antibodies, anti-ß2-glycoprotein I (anti-ß2-GPI) antibodies and lupus anticoagulant (LAC) were measured, and other clinical and pathological data were also obtained during the same period before renal biopsy. RESULTS: A total of 83 patients with LN were included in this study, 40 patients (48.2%) in the s positive group and 43 patients in the aPL negative group. LN patients with positive aPL had significantly higher SLEDAI (p = 0.012), more hematuria (p = 0.043), lower serum C3 (p = 0.003) and C4 (p = 0.014), and a higher pathological activity index (p = 0.012), more micro-thrombosis (p = 0.046) and more C3 deposits (p = 0.038) in the glomerulus than patients with negative aPL The level of IgG- was significantly correlated with SLEDAI and serum level of C3 (r = 0.44, p < 0.001; r = -0.39, p = 0.003, respectively). The level of IgM- was significantly correlated with SLEDAI, and serum levels of C3 and C4 (r = 0.27, p = 0.014; r = -0.22, p = 0.041; r = -0.23, p = 0.035, respectively). CONCLUSIONS: Our work suggests that aPL, especially, are correlated with both clinical activity and renal pathological activity in patients with LN.