BACKGROUND: Immunoglobulin A nephropathy (IgAN) is the most common pathological type of glomerular disease. Kidney biopsy, the gold standard for IgAN diagnosis, has not been routinely applied in hospitals worldwide due to its invasion nature. Thus, we aim to establish a non-invasive diagnostic model and determine markers to evaluate disease severity by analyzing the serological parameters and pathological stages of patients with IgAN. METHODS: A total of 272 biopsy-diagnosed IgAN inpatients and 518 non-IgA nephropathy inpatients from the Department of Nephrology of Chinese People's Liberation Army General Hospital were recruited for this study. Routine blood examination, blood coagulation testing, immunoglobulin-complement testing, and clinical biochemistry testing were conducted and pathological stages were analyzed according to Lee grading system. The serological parameters and pathological stages were analyzed. The receiver operating characteristic (ROC) analysis was performed to estimate the diagnostic value of the clinical factors. Logistic regression was used to establish the diagnostic model. RESULTS: There were 15 significantly different serological parameters between the IgAN and non-IgAN groups (all P < 0.05). The ROC analysis was performed to measure the diagnostic value for IgAN of these parameters and the results showed that the area under the ROC curve (AUC) of total protein (TP), total cholesterol (TC), fibrinogen (FIB), D-dimer (D2), immunoglobulin A (IgA), and immunoglobulin G (IgG) were more than 0.70. The AUC of the "TC + FIB + D2 + IgA + age" combination was 0.86, with a sensitivity of 85.98% and a specificity of 73.85%. Pathological grades of I, II, III, IV, and V accounted for 2.21%, 17.65%, 62.50%, 11.76%, and 5.88%, respectively, with grade III being the most prevalent. The levels of urea nitrogen (UN) (13.57 ± 5.95 vs. 6.06 ± 3.63, 5.92 ± 2.97, 5.41 ± 1.73, and 8.41 ± 3.72 mmol/L, respectively) and creatinine (Cr) (292.19 ± 162.21 vs. 80.42 ± 24.75, 103.79 ± 72.72, 96.41 ± 33.79, and 163.04 ± 47.51 μmol/L, respectively) were significantly higher in grade V than in the other grades, and the levels of TP (64.45 ± 7.56, 67.16 ± 6.94, 63.22 ± 8.56, and 61.41 ± 10.86 vs. 37.47 ± 5.6 mg/d, respectively), direct bilirubin (DB) (2.34 ± 1.23, 2.58 ± 1.40, 1.91 ± 0.97, and 1.81 ± 1.44 vs. 0.74 ± 0.57 μmol/L, respectively), and IgA (310.35 ± 103.78, 318.48 ± 107.54, 292.58 ± 81.85, and 323.29 ± 181.67 vs. 227.17 ± 68.12 g/L, respectively) were significantly increased in grades II-V compared with grade I (all P < 0.05). CONCLUSIONS The established diagnostic model that combined multiple factors (TC, FIB, D2, IgA, and age) might be used for IgAN non-invasive diagnosis. TP, DB, IgA, Cr, and UN have the potential to be used to evaluate IgAN disease severity.
Adult ; Biomarkers ; blood ; Blood Urea Nitrogen ; Cholesterol ; blood ; Creatinine ; blood ; Female ; Fibrinogen ; metabolism ; Glomerulonephritis, IGA ; blood ; diagnosis ; pathology ; Humans ; Immunoglobulin A ; blood ; Logistic Models ; Male ; Middle Aged ; Multivariate Analysis ; ROC Curve

Female ; Glomerulonephritis, IGA ; metabolism ; pathology ; Glomerulonephritis, Membranous ; metabolism ; pathology ; Glomerulosclerosis, Focal Segmental ; metabolism ; pathology ; Humans ; Kidney ; metabolism ; pathology ; Male ; Renal Insufficiency, Chronic ; metabolism ; pathology

BACKGROUND/AIMS: Tubulointerstitial injury plays an important role in the progression of immunoglobulin A nephropathy (IgAN), and neutrophil gelatinase-associated lipocalin (NGAL) is among the most sensitive tubular biomarkers. We investigated whether serum or urine NGAL predicts prognosis in patients with IgAN. METHODS: The present study enrolled patients with biopsy-proven IgAN from January 2005 to December 2010, whose serum and urine samples at the time of kidney biopsy were preserved by freezing. We retrospectively reviewed patient clinical data and followed patients until October 2012. Serum and urine NGAL levels were measured using an enzyme-linked immunosorbent assay kit. Renal progression was defined as an estimated glomerular filtration rate decline by > 50% or progression to end-stage renal disease. RESULTS: There were 121 patients enrolled in this study. During the median follow-up period of 41.49 months, renal progression was found in nine patients (7.4%). Serum or urine NGAL alone could not predict renal progression; however, when serum and urine NGAL levels were combined, belonging to the high NGAL group independently predicted renal progression (hazard ratio [HR], 5.56; 95% confidence interval [CI], 1.42 to 21.73; p = 0.014), along with tubular damage graded according to the Oxford classification as T2 (HR, 8.79; 95% CI, 2.01 to 38.51; p = 0.004). In addition, a Kaplan-Meier curve of renal survival showed significantly higher renal progression in patients in the high NGAL group (log rank, p = 0.004). CONCLUSIONS: In patients with IgAN, high serum and urine NGAL levels at the time of kidney biopsy predict renal progression.
Acute-Phase Proteins/*urine ; Adult ; Biomarkers/blood/urine ; Biopsy ; Chi-Square Distribution ; Disease Progression ; Enzyme-Linked Immunosorbent Assay ; Female ; Glomerular Filtration Rate ; Glomerulonephritis, IGA/*blood/complications/pathology/physiopathology/*urine ; Humans ; Kaplan-Meier Estimate ; Kidney/*metabolism/pathology/physiopathology ; Lipocalins/*blood/*urine ; Male ; Middle Aged ; Multivariate Analysis ; Predictive Value of Tests ; Prognosis ; Proportional Hazards Models ; Proto-Oncogene Proteins/*blood/*urine ; Retrospective Studies ; Risk Factors ; Young Adult

BACKGROUND/AIMS: Neutrophil gelatinase-associated lipocalin (NGAL) is a well-known biomarker of acute kidney injury. We evaluated the value of plasma NGAL (pNGAL) as an independent predictor of prognosis in immunoglobulin A nephropathy (IgAN). METHODS: In total, 91 patients with biopsy-proven IgAN at a single center were evaluated. pNGAL was measured using a commercial enzyme-linked immunosorbent assay kit (R&D Systems). Adverse renal outcome was defined as chronic kidney disease (CKD) stage 3 or above at the last follow-up. Pearson correlation coefficient and Cox regression were used for analyses. RESULTS: The mean age of all patients (male:female, 48:43) was 35 years (range, 18 to 77). pNGAL ranged between 21.68 and 446.40 ng/mL (median, 123.97) and showed a correlation with age (r = 0.332, p = 0.001), creatinine (r = 0.336, p = 0.001), estimated glomerular filtration rate (r = -0.397, p < 0.001), uric acid (r = 0.289, p = 0.006), and the protein-to-creatinine ratio (r = 0.288, p = 0.006). During a mean follow-up period of 37.6 months, 11 patients (12.1%) had CKD stage 3 or above. In a multivariate Cox regression model, hypertension (hazard ratio [HR], 8.779; 95% confidence interval [CI], 1.526 to 50.496; p = 0.015), proteinuria > 1 g/day (HR, 5.184; 95% CI, 1.124 to 23.921; p = 0.035), and pNGAL (HR, 1.012; 95% CI, 1.003 to 1.022; p = 0.013) were independent predictors associated with adverse renal outcome. CONCLUSIONS: pNGAL showed strong correlations with other clinical prognostic factors and was also an independent predictor of adverse renal outcome. We suggest pNGAL as a potential predictor for prognosis in IgAN, while further studies are needed to confirm the clinical value.
Acute-Phase Proteins ; Adolescent ; Adult ; Aged ; Biomarkers/blood ; Biopsy ; Chi-Square Distribution ; Creatinine/blood ; Disease Progression ; Enzyme-Linked Immunosorbent Assay ; Female ; Glomerular Filtration Rate ; Glomerulonephritis, IGA/*blood/complications/pathology/physiopathology ; Humans ; Kidney/*metabolism/pathology/physiopathology ; Linear Models ; Lipocalins/*blood ; Male ; Middle Aged ; Multivariate Analysis ; Predictive Value of Tests ; Prognosis ; Proportional Hazards Models ; Proto-Oncogene Proteins/*blood ; Renal Insufficiency, Chronic/blood/etiology ; Republic of Korea ; Retrospective Studies ; Risk Factors ; Time Factors ; Young Adult

OBJECTIVETo investigate the clinical significance of transforming growth factor-beta 1 (TGF-β1) in children with primary IgA nephropathy (IgAN).

METHODSThirty children who were diagnosed with primary IgAN by renal biopsy between May 2008 and October 2012 were included in the study. Thirty healthy children were used as the control group. Urinary and blood TGF-β1 levels were measured using enzyme-linked immunosorbent assay, and the protein expression of TGF-β1 in the renal tissue was measured by immunohistochemistry. The correlation between TGF-β1 levels in blood, urine, and renal tissue and their relationship with clinical indices were analyzed.

RESULTSChildren with primary IgAN had significantly higher urinary and blood TGF-β1 levels than the control group (P<0.01). Urinary TGF-β1 level was positively correlated with the pathological grade of renal tissue (r=0.557, P=0.001), and a significant positive correlation was also found between the TGF-β1 expression in the renal tissue and the pathological grade of renal tissue (r=0.682, P<0.01). There was no correlation between TGF-β1 levels in blood and renal tissue (r=0.038, P=0.844).

CONCLUSIONSUrinary TGF-β1 level is significantly positively correlated with the pathological severity of disease in children with primary IgAN. Clinical measurement of urinary TGF-β1 may be of great practical value in predicting the progression and prognosis of chronic nephropathy.

Adolescent ; Child ; Female ; Glomerulonephritis, IGA ; metabolism ; pathology ; Humans ; Kidney ; chemistry ; pathology ; Male ; Transforming Growth Factor beta1 ; analysis ; physiology ; urine

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

Glomerulonephritis occurs as a rare form of renal manifestation in Plasmodium falciparum malaria. Herein, we report a case of falciparum malaria-associated IgA nephropathy for the first time. A 49-yr old male who had been to East Africa was diagnosed with Plasmodium falciparum malaria. Microhematuria and proteinuria along with acute kidney injury developed during the course of the disease. Kidney biopsy showed mesangial proliferation and IgA deposits with tubulointerstitial inflammation. Laboratory tests after recovery from malaria showed disappearance of urinary abnormalities and normalization of kidney function. Our findings suggest that malaria infection might be associated with IgA nephropathy.
Acute Kidney Injury/etiology/pathology ; Antimalarials/therapeutic use ; Creatinine/blood ; Glomerulonephritis, IGA/*diagnosis/*etiology ; Hematuria/etiology ; Humans ; Immunoglobulin A/*metabolism ; Malaria/*complications/drug therapy/*pathology ; Male ; Middle Aged ; Plasmodium falciparum/*isolation & purification ; Proteinuria/etiology ; Quinine/therapeutic use

OBJECTIVETo study the expression of neonatal Fc receptor in podocytes in human nephritis and immune-induced rat nephritis models: anti-Thy1.1 nephritis and Heymann nephritis.

METHODSThirty-nine cases of renal biopsies were enrolled from September 2009 to February 2010, including 8 cases of minimal change disease, 4 cases of focal segmental glomerulosclerosis, 9 cases of membranous nephropathy, 12 cases of IgA nephropathy and 6 cases of lupus nephritis. Five normal kidney tissue samples adjacent to renal clear-cell carcinoma were served as normal controls. Laser capture microdissection and real-time RT-PCR were used to assess the expression level of FcRn mRNA in glomeruli of various glomerulonephritides, and immunohistochemistry (IHC) of FcRn by SuperVision method was performed. In addition, rat models of mesangial proliferative nephritis (anti-Thy1.1 nephritis) and passive membranous nephropathy (Heymann nephritis) were established and FcRn was examined in renal tissues by IHC.

RESULTSThe FcRn mRNA level in lupus nephritis was statistically higher than that of normal controls (P < 0.05). FcRn protein expression by IHC was seen in lupus nephritis (6/6), membranous nephropathy (6/9) and IgA nephropathy (7/12), significantly higher than that of normal controls (0/5), P < 0.05. Minimal change disease and focal segmental glomerular sclerosis showed minimal or none expression of FcRn (1/8, 0/4 respectively) and not statistically difference from that of normal controls. Furthermore, FcRn expression in podocytes was detected in rat anti-Thy1.1 (3/5) and Heymann nephritis models (2/7) but was not detected in normal controls.

CONCLUSIONSExpression of FcRn in podocytes was up-regulated in immune-induced human nephritis and rat nephritis models of anti-Thy1.1 nephritis and Heymann nephritis. FcRn may play a role in the development of immune-induced glomerulonephritis.

Animals ; Glomerulonephritis, IGA ; metabolism ; pathology ; Glomerulonephritis, Membranous ; metabolism ; pathology ; Glomerulosclerosis, Focal Segmental ; metabolism ; pathology ; Histocompatibility Antigens Class I ; genetics ; metabolism ; Humans ; Laser Capture Microdissection ; Lupus Nephritis ; metabolism ; pathology ; Male ; Nephritis ; genetics ; immunology ; metabolism ; pathology ; Nephrosis, Lipoid ; metabolism ; pathology ; Podocytes ; metabolism ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction ; Receptors, Fc ; genetics ; metabolism ; Thy-1 Antigens ; immunology ; metabolism ; Up-Regulation

CD36 Antigens ; metabolism ; Cell Aggregation ; Cholesterol ; blood ; Foam Cells ; pathology ; Glomerulonephritis, IGA ; blood ; metabolism ; pathology ; Glomerulonephritis, Membranoproliferative ; blood ; metabolism ; pathology ; Glomerulonephritis, Membranous ; blood ; metabolism ; pathology ; Glomerulosclerosis, Focal Segmental ; blood ; metabolism ; pathology ; Humans ; Nephritis ; blood ; metabolism ; pathology ; Nephritis, Hereditary ; blood ; metabolism ; pathology

OBJECTIVETo examine the cellular components at different stages of the crescent formation in four most common types of human crescentic glomerulonephritis (CGN), including anti-GBM disease (GBM-CGN), crescentic IgA nephropathy (IgA-CGN), ANCA associated pauci-immune CGN (ANCA-CGN) and crescentic lupus glomerulonephritis (LN-CGN).

METHODSRenal biopsy specimens of patients with GBM-CGN (n = 10), IgA-CGN (n = 12), ANCA-CGN (n = 12), and LN-CGN (n = 11) were selected. Immunohistochemistry was adopted to identify the cellular components using different cell markers including cytokeratin (PEC), CD68 (macrophage), nestin (podocyte), podocalyxin (podocyte), CD3 (lymphocyte), CD15 (neutrophil) and PCNA.

RESULTSThere were different subtypes of cell components identified during the formation of a cellular crescent in 4 different types of human CGN. Mainly of PEC 11.4 (0.0, 95.0)%, macrophage 8.0 (0.0, 35.0)% and podocyte 5.5 (0.0, 22.0)% and their constitutive percentages were different among various CGNs (P < 0.01). In all the CGNs studied, there were 50% of cells were negative to all the cell markers adopted for this expeiment. Podocalyxin positive cells 0.5 (0.0, 9.6)% were significantly less than nestin positive cells 5.5 (0.0, 22.0)% in all CGNs. PCNA positive cells were 44.7 (16.7, 83.3)% in the cellular crescent of all CGNs and co-localized with nestin (38/45 cases), CK (42/45 cases) or CD68 (24/45 cases).

CONCLUSIONSPEC, macrophage and podocyte might play important roles in the formation of crescents. The staining disparity of nestin and podocalyxin indicates that podocyte dedifferentiation may occur during the crescent formation. PEC, podocytes and macrophages may participate in the formation of crescent in common CGNs through active cellular proliferation.

Anti-Glomerular Basement Membrane Disease ; metabolism ; pathology ; Antibodies, Antineutrophil Cytoplasmic ; metabolism ; Antigens, CD ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; Cell Proliferation ; Epithelial Cells ; metabolism ; pathology ; Glomerulonephritis ; classification ; metabolism ; pathology ; Glomerulonephritis, IGA ; metabolism ; pathology ; Humans ; Intermediate Filament Proteins ; metabolism ; Keratins ; metabolism ; Lupus Nephritis ; metabolism ; pathology ; Macrophages ; metabolism ; pathology ; Nerve Tissue Proteins ; metabolism ; Nestin ; Podocytes ; metabolism ; pathology ; Proliferating Cell Nuclear Antigen ; metabolism ; Sialoglycoproteins ; metabolism