Long-term exposure to particulate matter has been increasingly implicated in the progression of chronic kidney disease (CKD). However, its impact on IgA nephropathy (IgAN), a leading cause of end-stage renal disease (ESRD), remains unclear. A total of 1768 IgAN patients, confirmed by renal biopsy were included in this cohort study. Long-term exposure to PM_2.5 and PM₁₀ was assessed using high-resolution satellite-based data from the China High Air Pollutants (CHAP) dataset. Cox proportional hazards models were used to estimate the associations between PM_2.5 or PM₁₀ and ESRD risk, adjusting for demographic, clinical, and biochemical covariates. Over a median follow-up of 3.63 years, 209 participants progressed to ESRD. Higher exposure to both PM_2.5 and PM₁₀ was significantly associated with an increased risk, with hazard ratios of 1.62 and 1.36 per 10 µg/m³ increase, respectively. A nonlinear dose-response relationship was observed, with risk increasing markedly beyond threshold levels. Trajectory modeling of prebaseline exposure identified a subgroup with persistently high and fluctuating particulate matter exposure that showed the highest risk. This study provides strong evidence that prolonged exposure to ambient particulate matter contributes to renal disease progression in individuals with IgAN.
Humans ; Glomerulonephritis, IGA/pathology* ; Particulate Matter/adverse effects* ; Male ; Female ; Kidney Failure, Chronic/epidemiology* ; Adult ; China/epidemiology* ; Disease Progression ; Environmental Exposure/adverse effects* ; Middle Aged ; Proportional Hazards Models ; Risk Factors ; Air Pollutants/adverse effects* ; Cohort Studies

Cardiovascular disease (CVD) is the most common cause of death in patients with chronic kidney disease (CKD). We report the baseline cardiovascular characteristics of 2,238 participants by using the data of the KoreaN Cohort Study for Outcomes in Patients With Chronic Kidney Disease (KNOW-CKD) study. The cohort comprises 5 subcohorts according to the cause of CKD: glomerulonephritis (GN), diabetic nephropathy (DN), hypertensive nephropathy (HTN), polycystic kidney disease (PKD), and unclassified. The average estimated glomerular filtration rate (eGFR) was 50.5 ± 30.3 mL/min⁻¹/1.73 m⁻² and lowest in the DN subcohort. The overall prevalence of previous CVD was 14.4% in all patients, and was highest in the DN followed by that in the HTN subcohort. The DN subcohort had more adverse cardiovascular risk profiles (higher systolic blood pressure [SBP], and higher levels of cardiac troponin T, left ventricular mass index [LVMI], coronary calcium score, and brachial-ankle pulse wave velocity [baPWV]) than the other subcohorts. The HTN subcohort exhibited less severe cardiovascular risk profiles than the DN subcohort, but had more severe cardiovascular risk features than the GN and PKD subcohorts. All these cardiovascular risk profiles were inversely correlated with eGFR. In conclusion, this study shows that the KNOW-CKD cohort exhibits high cardiovascular burden, as other CKD cohorts in previous studies. Among the subcohorts, the DN subcohort had the highest risk for CVD. The ongoing long-term follow-up study up to 10 years will further delineate cardiovascular characteristics and outcomes of each subcohort exposed to different risk profiles.
Adult* ; Blood Pressure ; Calcium ; Cardiovascular Diseases ; Cause of Death ; Cohort Studies* ; Diabetic Nephropathies ; Epidemiology ; Follow-Up Studies ; Glomerular Filtration Rate ; Glomerulonephritis ; Humans ; Hypertension ; Polycystic Kidney Diseases ; Prevalence ; Pulse Wave Analysis ; Renal Insufficiency, Chronic* ; Troponin T

The KoreaN Cohort Study for Outcomes in Patients With Chronic Kidney Disease (KNOW-CKD) was developed to investigate various clinical courses and risk factors for progression of Korean chronic kidney disease (CKD). The KNOW-CKD study consists of nine clinical centers in Korea, and patients aged between 20 and 75 years with CKD from stage 1 to 5 (predialysis) were recruited. At baseline, blood and urine samples were obtained and demographic data including comorbidities, drugs, quality of life, and health behaviors were collected. Estimated glomerular filtration rate (eGFR) was calculated by 4-variable Modification of Diet in Renal Disease (MDRD) equation using isotope dilution mass spectrometry (IDMS)-calibrated serum creatinine measured at a central laboratory. As a dynamic cohort, a total of 2,341 patients were enrolled during the enrollment period from 2011 until 2015, among whom 2,238 subjects were finally analyzed for baseline profiles. The mean age of the cohort was 53.7 ± 12.2 year and 61.2% were men. Mean eGFR was 50.5 ± 30.3 mL/min/1.73 m². The participants with lower eGFR had a tendency to be older, with more comorbidities, to have higher systolic blood pressure (BP) and pulse pressure, with lower income level and education attainment. The patients categorized as glomerulonephritis (GN) were 36.2% followed by diabetic nephropathy (DN, 23.2%), hypertensive nephropathy (HTN, 18.3%), polycystic kidney disease (PKD, 16.3%), and other unclassified disease (6.1%). The KNOW-CKD participants will be longitudinally followed for 10 years. The study will provide better understanding for physicians regarding clinical outcomes, especially renal and cardiovascular outcomes in CKD patients.
Blood Pressure ; Cohort Studies* ; Comorbidity ; Creatinine ; Diabetic Nephropathies ; Diet ; Education ; Epidemiology ; Glomerular Filtration Rate ; Glomerulonephritis ; Health Behavior ; Humans ; Hypertension ; Korea ; Male ; Mass Spectrometry ; Polycystic Kidney Diseases ; Quality of Life ; Renal Insufficiency, Chronic* ; Risk Factors

PURPOSE: Smoking reportedly exerts deleterious effects on renal function; however, its effects on histology have not been clarified in patients with IgA nephropathy (IgAN). MATERIALS AND METHODS: Renal histology was evaluated in a cohort of 397 patients diagnosed with IgAN according to smoking status and dose in relation to renal function. RESULTS: Among the study cohort, which was predominantly male (88.5%), 52 patients (13%) were current smokers. These current smokers demonstrated more frequent hypertension and higher serum creatinine levels than non/ex-smokers at the time of diagnosis, which was apparent with increased smoking dose. The percentages of global glomerulosclerosis and arteriolar hyalinosis increased with increased smoking dose, whereas tubulointerstitial fibrosis or arterial intimal thickening did not. Glomerular mesangial alpha-smooth muscle actin expression were similar between current and non/ex-smokers matched for age, gender, hypertension, and histologic severity, although the number of glomerular CD68+ cells was significantly fewer in smokers. Initial serum creatinine level, estimated glomerular filtration rate (eGFR), and global glomerulosclerosis were found to be risk factors of serum creatinine doubling in both smokers and non/ex-smokers by univariate analysis during a mean follow-up of 3.8 years. CONCLUSION: In addition to dose dependent renal functional decline and hypertension, smoking contributes to renal disease progression by eliciting microvascular injury in IgAN patients.
Adult ; Aged ; Case-Control Studies ; Cohort Studies ; Creatinine/blood ; Disease Progression ; Female ; Glomerulonephritis, IGA/blood/*diagnosis/epidemiology ; Humans ; Immunohistochemistry ; Kidney/*pathology ; Kidney Function Tests ; Kidney Glomerulus/*pathology ; Male ; Middle Aged ; Risk Factors ; Smoking/*adverse effects/epidemiology

Poststreptococcal glomerulonephritis (PSGN) is one of the most recognized diseases in pediatric nephrology. Typical clinical features include rapid onset of gross hematuria, edema, and hypertension, and cases are typically preceded by an episode of group A β-hemolytic streptococcus pharyngitis or pyoderma. The most common presenting symptoms of PSGN are the classic triad of glomerulonephritis: gross hematuria, edema, and hypertension . However, patients with PSGN sometimes present with unusual or atypical clinical symptoms that often lead to delayed diagnosis or misdiagnosis of the disease and increased morbidity. Additionally, the epidemiology of postinfectious glomerulonephritis (PIGN), including PSGN, has changed over the past few decades. This paper reviews atypical clinical manifestations of PSGN and discusses the changing demographics of PIGN with a focus on PSGN.
Delayed Diagnosis ; Demography ; Diagnostic Errors ; Edema ; Epidemiology ; Glomerulonephritis* ; Hematuria ; Humans ; Hypertension ; Nephrology ; Pharyngitis ; Pyoderma ; Streptococcus

To examine levels of M-type phospholipase A2 receptor (PLA2R) and its antibody in the patients with hepatitis B virus-associated membranous nephropathy (HBV-MN), and to explore the correlation of PLA2R with laboratory parameters and pathological characteristics.
 Methods: A total of 49 adult patients with biopsy-proved HBV-MN were enrolled in this study. Levels of anti-PLA2R antibody in serum and PLA2R in renal tissue were detected. Patients were assigned into two groups: a positive PLA2R group and a negative PLA2R group. Differences in laboratory parameters and pathological characteristics were compared between the two groups.
 Results: Of 49 patients with HBV-MN, 17 had positive PLA2R expression in renal tissues. In the positive PLA2R group, 10 patients were positive for serum anti-PLA2R antibody. Patients with positive PLA2R expression in renal tissues showed higher levels of 24 hour urinary protein [(4.6±3.9) g/d], serum HbsAg (70.5%) and renal HbsAg expression (71%), while lower level of serum albumin [(24.1±7.5) g/L] than those of the negative group.
 Conclusion: PLA2R is expressed in the renal tissues and serum anti-PLA2R antibody can be detected in some HBV-MN patients. Positive PLA2R expression in renal tissue might be related to HbsAg deposition in serum and renal tissues. Patients with positive PLA2R expression in renal tissue have more severe glomerular sclerosis.
Adult ; Antibodies ; Autoantibodies ; genetics ; physiology ; Biopsy ; Glomerulonephritis, Membranous ; complications ; etiology ; genetics ; Hepatitis B ; complications ; Hepatitis B Surface Antigens ; adverse effects ; Hepatitis B virus ; Humans ; Kidney ; blood supply ; chemistry ; physiopathology ; Kidney Diseases ; etiology ; genetics ; physiopathology ; Male ; Prognosis ; Proteinuria ; epidemiology ; genetics ; Receptors, Phospholipase A2 ; blood ; physiology ; Serum Albumin ; genetics

PURPOSE: The incidence of acute poststreptococcal glomerulonephritis (APSGN) in Korea has changed. This study aimed to evaluate the epidemiological and clinical changes of APSGN observed in a single Korean institution over two decades. METHODS: We retrospectively analyzed the data of 99 children (0-15 years of age) who were admitted to our institution with APSGN between 1987 and 2013. The patients were selected based on the depression of serum complement 3 (C3, <70 mg/dL) and elevated titer of antistreptolysin O (ASO, >250 IU/dL) as evidence of previous streptococcal infection. RESULTS: In the 99 patients, the mean age was 8.3 +/- 2.7 years, and the male-tofemale ratio was 2.2:1 (66:30). The annual number of cases fluctuated markedly, and most cases were observed during the late autumn and winter months. However, there have been few cases reported in the past 5 years. Clinical manifestations at presentation, including hypertension and generalized oedema, and the duration of hospitalization were higher and longer in patients admitted during the first half of the study period than during the most recent half-period, suggesting a more severe clinical course in the former group. CONCLUSIONS: APSGN has become a rare disease in Korea with a trend towards a less severe clinical course. This finding suggests that the prevalence of infection-related immune-mediated diseases could change over-time, together with environmental and possibly pathogen-host relationship changes.
Antistreptolysin ; Child ; Complement C3 ; Depression ; Epidemiology ; Glomerulonephritis* ; Hospitalization ; Humans ; Hypertension ; Incidence ; Korea ; Prevalence ; Rare Diseases ; Retrospective Studies ; Streptococcal Infections

BACKGROUNDIgA nephropathy (IgAN) is the most common primary glomerular disease. Transforming growth factor β1 (TGFβ1) plays an important role in pathogenesis of IgAN. Associations between the polymorphisms of TGFβ1 gene and the risk of IgAN remained inconsistent. A meta-analysis was conducted to investigate the association between polymorphisms in the TGFβ1 gene and IgAN susceptibility.

METHODSDatabases including Pubmed, EMBASE, ISI, et al. were searched to find relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to evaluate the strength of associations.

RESULTSTen studies involving 1770 cases and 1953 controls were included. Significant association between C509T polymorphism and IgAN risk was observed (OR 1.42, 95% CI 1.12-1.81, P = 0.0004; I(2) = 0%) in Caucasians by the overdominant model (CT vs. CC + TT), but no significant association was found (P = 0.200) in Asians by the dominant model (CC + CT vs. TT). Significant association between T869C polymorphism and IgAN susceptibility was found (OR 1.21, 95% CI 1.02-1.44, P = 0.030) in overall populations by the dominant model (TT + TC vs. CC). Subgroup analysis found T allele of T869C polymorphism was associated with IgAN susceptibility in Caucasians (P = 0.030), but not in Asians (P = 0.290).

CONCLUSIONBoth heterozygotes of C509T polymorphism and T allele of T869C polymorphism in TGFβ1 were associated with the risk of IgAN in Caucasians, but not in Asians.

Asian Continental Ancestry Group ; genetics ; European Continental Ancestry Group ; genetics ; Genetic Predisposition to Disease ; genetics ; Glomerulonephritis, IGA ; epidemiology ; genetics ; Humans ; Polymorphism, Genetic ; genetics ; Transforming Growth Factor beta1 ; genetics

PURPOSE: Behcet's disease (BD) theoretically affects all sizes and types of blood vessels and results in multi-organ involvement. However, renal BD has not been fully characterized, though the kidneys are histologically rich in blood vessels. MATERIALS AND METHODS: A total of 2007 patients who fulfilled the diagnostic criteria for BD were enrolled in this study. We reviewed the medical records and test results of the BD patients and used univariate and multivariate logistic regression analyses to determine the clinical significance of renal involvement in BD. RESULTS: Among the 2007 BD patients, we noted hematuria in 412 (20.5%) and proteinuria in 29 (1.4%). Univariate analysis showed that the BD patients with hematuria were predominantly female and older, had higher erythrocyte sedimentation rates (ESRs), and more frequently presented with genital ulcerations. BD patients with proteinuria had higher ESR levels compared to BD patients without proteinuria. In the multivariate analysis, age, sex, and ESR were found to be significantly associated with hematuria in BD patients, whereas only ESR was associated with proteinuria in BD patients. We also found that IgA nephropathy was the most common pathologic diagnosis in 12 renal BD patients who underwent renal biopsies. CONCLUSION: We suggest that routine urinalysis and serum renal function tests be performed for the early detection of renal BD, especially in older female BD patients with recurrent hematuria, high ESR levels, and frequent genital ulcers, as well as in BD patients with proteinuria and high ESR levels.
Adolescent ; Adult ; Age Factors ; Aged ; Aged, 80 and over ; Behcet Syndrome/*complications/epidemiology/*metabolism ; Biopsy ; Female ; Glomerulonephritis, IGA/complications/diagnosis ; Hematuria/complications/diagnosis ; Humans ; Kidney/*pathology ; Kidney Diseases/*diagnosis ; Logistic Models ; Male ; Middle Aged ; Multivariate Analysis ; Proteinuria/complications/diagnosis ; Republic of Korea ; Young Adult

BACKGROUND/AIMS: The recently published Oxford classification of IgA nephropathy (IgAN) proposed a split system for histological grading, based on prognostic pathological features. This new classification system must be validated in a variety of cohorts. We investigated whether these pathological features were applicable to an adult Korean population. METHODS: In total, 69 adult Korean patients with IgAN were analyzed using the Oxford classification system at Soonchunhyang University Hospital, Seoul, Korea. All cases were categorized according to Lee's classification. Renal biopsies from all patients were scored by a pathologist who was blinded to the clinical data for pathological variables. Inclusion criteria were age greater than 18 years and at least 36 months of follow-up. We excluded cases with secondary IgAN, diabetic nephropathy combined other glomerulopathies, less than 36 months of follow-up, and those that progressed rapidly. RESULTS: The median age of the patients was 34 years (range, 27 to 45). Mean arterial blood pressure was 97 +/- 10 mmHg at the time of biopsy. The median follow-up period was 85 months (range, 60 to 114). Kaplan-Meier analysis showed significant prognostic predictions for M, E, and T lesions. A Cox proportional hazard regression analysis also revealed prognostic predictions for E and T lesions. CONCLUSIONS: Using the Oxford classification in IgAN, E, and T lesions predicted renal outcome in Korean adults after taking clinical variables into account.
Adult ; *Asian Continental Ancestry Group ; Biopsy ; Chi-Square Distribution ; Disease Progression ; Female ; Fish Oils/therapeutic use ; Glomerulonephritis, IGA/classification/*diagnosis/ethnology/pathology/therapy ; Hospitals, University ; Humans ; Immunosuppressive Agents/therapeutic use ; Kaplan-Meier Estimate ; Kidney/*pathology ; Male ; Middle Aged ; Multivariate Analysis ; Predictive Value of Tests ; Prognosis ; Proportional Hazards Models ; Reproducibility of Results ; Republic of Korea/epidemiology ; Retrospective Studies ; Severity of Illness Index ; Time Factors