Long term outcome of immunoglobulin A (IgA) nephropathy: A single center experience

Are Platelet-Related Parameters Prognostic Predictors of Renal and Cardiovascular Outcomes in IgA Nephropathy?

Background: IgA nephropathy (IgAN) is associated with chronic inflammation. Platelet-related parameters, such as the platelet (PLT) count, platelet-to-albumin ratio (PAR), and platelet-to-lymphocyte ratio (PLR), were examined as potential prognostic indicators for renal and cardiovascular (CV) outcomes in IgAN. We were interested in whether platelet-related parameters are risk factors for ESKD and CV events in IgAN patients. Methods: In a monocentric retrospective study, 124 IgAN patients were divided into two groups based on the cut-off value of the PAR. All-cause mortality, major CV events, and end-stage renal disease were the primary combined endpoints. Secondary endpoints, such as CV or renal endpoints, were also analyzed separately. Results: The patients' mean age was 43.7 ± 13.5 years, and the follow-up time was 124 ± 67 months. The K-M curve showed that the PLR, PAR, and PLT were strongly associated with primary combined (p = 0.002, p = 0.004, p = 0.001) and renal outcomes (p < 0.001, p < 0.001, p < 0.001), but not with CV outcomes in IgAN. However, when combined with left ventricular hypertrophy (LVH) or metabolic syndrome (MetS), the PAR was found to be a significant predictor of both primary (p < 0.001, p < 0.001) and secondary outcomes (p = 0.001 and p = 0.038; p = 0.001 and p = 0.015). Additionally, the PLR correlated with albuminuria (r = -0.165, p = 0.033) and LVH (r = -0.178, p = 0.025), while PLT correlated with eGFR (r = 0.158, p = 0.040). Conclusions. Elevated PARs and PLRs may predict progression to end-stage kidney disease, but in combination with LVH and MetS, they were related to CV events in IgAN. The determination of PARs and PLRs can be useful and cost-effective parameters for assessing both cardiovascular and renal risks in IgAN.

The predictive value and response to immunosuppressive therapy of IgA nephropathy patients with crescents in a large retrospective Chinese cohort

Background

The prognostic value and response to immunosuppressive therapy (IST) of patients with crescents in the different backgrounds of pathological presentations in immunoglobulin A nephropathy (IgAN) is unclear.

Methods

A total of 1262 IgAN patients were enrolled. Crescents (C, 0/1/2), fibrinoid necrosis (FN, 0/1) and endocapillary hypercellularity (E, 0/1) were integrated into different degrees of glomerular activity (0-4 points): mild (0), moderate (1-2) and severe (≥3). The effect of IST on patients with different glomerular activity scores and chronic tubular and interstitial lesions (T, 0/1/2) were analysed using Cox regression analysis. The kidney outcome was defined as an estimated glomerular filtration rate decrease ≥30% or end-stage kidney disease.

Results

C2 was an independent risk factor for kidney outcomes {overall cohort: hazard ratio [HR] 1.85 [95% confidence interval (CI) 1.03-3.31], P = .040; T0 patients: HR 6.52 [95% CI 2.92-14.54], P < .001; reference to C0} in those without IST, while the HR decreased to 0.83 (95% CI 0.54-1.27; P = .396) in the overall cohort and 2.39 (95% CI 1.00-5.67; P = .049) in T0 patients with IST. For patients with severe glomerular activity, IST decreased the risk of kidney outcomes by 70% in the overall cohort [HR 0.30 (95% CI 0.12-0.74), P = .009; reference to those without IST] and 86% in T0 patients [HR 0.14 (95% CI 0.04-0.54), P = 0.005; reference to those without IST].

Conclusions

IST could reduce the risk for kidney outcomes in IgAN patients with C2 and T0 lesions together, as well as in those with crescents and at least one other active lesion, including FN and E1 lesions.

Detection of N‑glycoprotein associated with IgA nephropathy in urine as a potential diagnostic biomarker using glycosylated proteomic analysis

The aim of the present study was to elucidate the potential diagnostic value of urinary N-glycoprotein in patients with IgA nephropathy (IgAN) using mass spectrometry (MS). All procedures were performed between June 2021 and June 2023 at Guangan People's Hospital (Guangan, China). Fresh mid-morning fasting midstream urine samples were collected from a total of 30 patients with IgAN and 30 sex- and age-matched healthy volunteers. Data acquired from 6 participants are available through ProteomeXchange with the identifier PXD041151. By comparison between the IgAN group (n=3) and healthy controls (n=3) and selection criteria of P<0.05 and |log fold-change|>2, a total of 11 upregulated and 22 downregulated glycoproteins in patients with IgAN were identified. The results of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses suggested that glycoproteins are involved in various functions, such as the regulation of cell growth, cell adhesion, cellular component organization and protein binding, as well as multiple pathways, including p53, Notch and mTOR signaling pathways. The urine levels of afamin were further measured by ELISA in a validation cohort to assess the diagnostic performance of the single indicator model. In conclusion, MS-based proteomics of urinary glycoproteins may be an alternative option for diagnosing patients with IgAN. Biomarkers of IgAN may include, but are not limited to, CCL25, PD-L1, HLA-DRB1, IL7RD and WDR82. In addition, the levels of urinary AFM indicators are of diagnostic value for IgAN.

Validation of the international IgA nephropathy prediction tool in a French cohort beyond 10 years after diagnosis

INTRODUCTION

The International IgA Nephropathy Network developed a tool (IINN-PT) for predicting the risk of end-stage renal disease (ESRD) or a 50% decline in the estimated glomerular filtration rate (eGFR). We aimed to validate this tool in a French cohort with longer follow-up than previously published validation studies.

METHODS

The predicted survival of patients with biopsy-proven immunoglobulin A nephropathy (IgAN) from the Saint Etienne University Hospital cohort was computed with IINN-PT models with or without ethnicity. The primary outcome was the occurrence of either ESRD or a 50% decline in eGFR. The models' performances were evaluated through c-statistics, discrimination and calibration analysis.

RESULTS

There were 473 patients with biopsy-proven IgAN, with a median follow-up of 12.4 years. Models with and without ethnicity showed areas under the curve (95% confidence interval) of 0.817 (0.765; 0.869) and 0.833 (0.791; 0.875) and R2D of 0.28 and 0.29, respectively, and an excellent discrimination of groups of increasing predicted risk (P < .001). The calibration analysis was good for both models up to 15 years after diagnosis. The model without ethnicity exhibited a mathematical issue of survival function after 15 years.

DISCUSSION

The IINN-PT provided good performances even after 10 years post-biopsy as showed by our study based on a cohort with a longer follow-up than previous cohorts (12.4 versus <6 years). The model without ethnicity exhibited better performances up to 15 years but became aberrant beyond this point due to a mathematical issue affecting the survival function. Our study sheds light on the usefulness of integrating ethnicity as a covariable for prediction of IgAN course.

Effect of high density lipoprotein cholesterol (HDL-C) on renal outcome in patients with nephrotic syndrome complicated with steroid-induced diabetes mellitus(SIDM)

OBJECTIVE

We aimed to investigate the renal prognosis of patients with idiopathic nephrotic syndrome (INS) complicated with steroid-induced diabetes mellitus (SIDM), the association of high-density lipoprotein cholesterol (HDL-C) before glucocorticoid treatment with renal prognosis, and the risk for persistent diabetes among patients with INS who had withdrawn from steroid therapy.

MATERIALS AND METHODS

We retrospectively analyzed 239 patients with INS complicated with SIDM at the National Clinical Research Center of Kidney Diseases, Jinling Hospital, from January 2008 to December 2019. The primary endpoint was the composite renal outcome defined as the development of end-stage renal disease (ESRD) or a 50% decrease in estimated glomerular filtration rate (eGFR) for more than 24 months after glucocorticoid withdrawal. The secondary endpoint was persistent diabetes, defined as fulfilling the criteria for diagnosing diabetes or using antidiabetic medications for at least 24 months after glucocorticoid withdrawal.

RESULTS

After glucocorticoid withdrawal for over 24 months, 35 (14.6%) patients reached the composite renal endpoint: end-stage renal disease (n = 14) or a 50% decrease in eGFR (n = 21). Before glucocorticoid therapy, a level of HDL-C greater than 1.45 mmol/L worsened renal survival in patients with INS complicated with SIDM. The log₁₀ the level of HDL-C before glucocorticoid treatment was an independent risk factor for the renal outcome. A prediction model was generated: Hazard ratio (renal outcome) = 0.94 * hypertension before glucocorticoid therapy + 2.29 * log₁₀ level of HDL-C before glucocorticoid treatment + 0.90 * the grade of interstitial tubule injury (AUROC, 0.75; 95% CI, 0.63 to 0.87; P < 0.01). Meanwhile, a level of fasting plasma glucose (FPG) before glucocorticoid treatment greater than 5.2 mmol/L enhanced the likelihood of persistent diabetes for at least 24 months after glucocorticoid withdrawal.

CONCLUSIONS

Increased level of HDL-C before glucocorticoid therapy was independently associated with a higher risk for renal outcome and thus may be useful in the renal prognosis of patients with INS complicated with SIDM.

Relationship between Traditional Chinese Medicine Syndrome Elements and Prognosis of Patients with IgA Nephropathy

Objective

It is not clear which Traditional Chinese Medicine- (TCM-) related elements affect primary IgA nephropathy (IgAN) progression. Here, we explored the risk factors, based on TCM syndrome elements, related to the prognosis of primary IgAN patients.

Methods

We analyzed patients with newly diagnosed, biopsy-proven IgAN at a single institution from December 2013 to September 2021. Basic clinical and pathological characteristics were assessed at the time of renal biopsy. The study endpoint was end-stage renal disease (ESRD: eGFR <15 ml/min per 1.73 m², dialysis, or kidney transplantation) and/or eGFR decreased by >30% from baseline. Kaplan‒Meier survival analysis was used to explore the role of TCM syndrome elements in IgAN progression. Multivariate Cox regression analysis with adjustment for traditional risk factors was performed to explore TCM syndrome elements that may influence patient prognosis. The factors correlated with TCM syndrome elements in IgAN patients were further evaluated by logistic regression analysis.

Results

During a median follow-up of 22.0 months, 53 (12.5%) of the 423 included IgAN patients reached the study endpoint. The main IgAN disease location elements were the kidney, liver, and spleen. The main IgAN disease nature elements were Yin-deficiency and Qi-deficiency, dampness, Yang-deficiency, phlegm, and Blood-deficiency. Kaplan‒Meier analysis identified three disease locations (liver, spleen, and kidney) and four disease natures (Qi-deficiency, Yang-deficiency, phlegm, and dampness) as elements associated with poor renal survival in IgAN patients. In multivariate Cox regression analysis, baseline Yang-deficiency was an independent risk predictor of poor prognosis in primary IgAN patients (hazard ratio 2.338; 95% confidence interval [CI]: 1.208–4.525; P=0.012) after adjustment for traditional risk factors. Furthermore, logistic regression analysis identified being female (odds ratio [OR] 2.518; 95% CI: 1.538–4.122; P < 0.001), older age (OR 1.043; 95% CI: 1.022–1.065; P < 0.001), low hemoglobin levels (OR 0.984; 95% CI: 0.971–0.996; P=0.013), and cellular/fibrocellular crescents (OR 1.706; 95% CI: 1.068–2.728; P=0.026) as factors affecting Yang-deficiency in IgAN patients.

Conclusions

Yang-deficiency independently predicts the risk of poor prognosis in primary IgAN patients. Being female, older age, low hemoglobin levels, and cellular/fibrocellular crescents were independently associated with Yang-deficiency in IgAN patients.

A noninvasive artificial neural network model to predict IgA nephropathy risk in Chinese population

Renal biopsy is the gold standard for Immunoglobulin A nephropathy (IgAN) but poses several problems. Thus, we aimed to establish a noninvasive model for predicting the risk probability of IgAN by analyzing routine and serological parameters. A total of 519 biopsy-diagnosed IgAN and 211 non-IgAN patients were recruited retrospectively. Artificial neural networks and logistic modeling were used. The receiver operating characteristic (ROC) curve and performance characteristics were determined to compare the diagnostic value between the two models. The training and validation sets did not differ significantly in terms of any variables. There were 19 significantly different parameters between the IgAN and non-IgAN groups. After multivariable logistic regression analysis, age, serum albumin, serum IgA, serum immunoglobulin G, estimated glomerular filtration rate, serum IgA/C3 ratio, and hematuria were found to be independently associated with the presence of IgAN. A backpropagation network model based on the above parameters was constructed and applied to the validation cohorts, revealing a sensitivity of 82.68% and a specificity of 84.78%. The area under the ROC curve for this model was higher than that for logistic regression model (0.881 vs. 0.839). The artificial neural network model based on routine markers can be a valuable noninvasive tool for predicting IgAN in screening practice.

Acute kidney injury in patients with primary nephrotic syndrome: influencing factors and coping strategies

Background

Acute kidney injury (AKI) is a frequent and serious complication in patients with primary nephrotic syndrome (PNS). We aimed to evaluate the influencing factors of AKI in patients with PNS, to provide implications for the clinical management and nursing care of patients with PNS.

Methods

PNS patients who were treated in the Department of Nephrology in our hospital from January 1, 2020 to July 31, 2021 were included. The clinical characteristics and pathological type of PNS patients were evaluated. Pearson correlation and Logistic regression analysis were performed to analyze the related risk factors of AKI in patients with PNS.

Results

A total of 328 patients with PNS were included, the incidence of AKI in PNS patients was 28.05%. Pearson correlation analysis showed that diabetes(r = 0.688), pulmonary infection (r = 0.614), albumin (r = 0.779), serum creatinine (r = 0.617), uric acid (r = 0.522), blood urea nitrogen (r = 0.616), renal tubular casts (r = 0.707) were correlated with AKI in PNS patients (all P < 0.05). Logistic regression analysis indicated that diabetes (OR2.908, 95%CI1.844 ~ 4.231), pulmonary infection(OR3.755, 95%CI2.831 ~ 4.987), albumin ≤ 24 g/L (OR1.923, 95%CI1.214 ~ 2.355), serum creatinine ≥ 90 μmol/L (OR2.517, 95%CI2.074 ~ 3.182), blood urea nitrogen ≥ 6.5 mmol/L (OR1.686, 95%CI1.208 ~ 2.123), uric acid ≥ 390 μmol/L (OR2.755, 95%CI2.131 ~ 3.371), renal tubular casts(OR1.796, 95%CI1.216 ~ 2.208) were the independently influencing factors of AKI in PNS patients (all P < 0.05).

Conclusions

AKI is common in PNS patients. Actively controlling diabetes and pulmonary infection, strengthening nutrition support and renal function monitoring are essential to reduce the occurrence of AKI in PNS patients.