Mass spectrometry-based proteomic analysis of proteins adsorbed by hexadecyl-immobilized cellulose bead column for the treatment of dialysis-related amyloidosis.

BACKGROUND: Dialysis-related amyloidosis (DRA) is a severe complication in end-stage kidney disease (ESKD) patients undergoing long-term dialysis treatment, characterized by the deposition of ß2-microglobulin-related amyloids (Aß2M amyloid). To inhibit DRA progression, hexadecyl-immobilized cellulose bead (HICB) columns are employed to adsorb circulating ß2-microglobulin (ß2M). However, it is possible that the HICB also adsorbs other molecules involved in amyloidogenesis. METHODS: We enrolled 14 ESKD patients using HICB columns for DRA treatment; proteins were extracted from HICBs following treatment and identified using liquid chromatography-linked mass spectrometry. We measured the removal rate of these proteins and examined the effect of those molecules on Aß2M amyloid fibril formation in vitro. RESULTS: We identified 200 proteins adsorbed by HICBs. Of these, 21 were also detected in the amyloid deposits in the carpal tunnels of patients with DRA. After passing through the HICB column and hemodialyzer, the serum levels of proteins such as ß2M, lysozyme, angiogenin, complement factor D and matrix Gla protein were reduced. These proteins acted in the Aß2M amyloid fibril formation. CONCLUSIONS: HICBs adsorbed diverse proteins in ESKD patients with DRA, including those detected in amyloid lesions. Direct hemoperfusion utilizing HICBs may play a role in acting Aß2M amyloidogenesis by reducing the amyloid-related proteins.

Fatal acute portal vein thrombosis associated with hepatic cysts in a patient with autosomal dominant polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD) often involves polycystic liver disease (PLD). In severe cases, PLD can develop various complications. However, fatal acute portal vein thrombosis (APVT) associated with PLD has not been reported. A 64-year-old male reported mild consciousness disorder. He had been under maintenance hemodialysis for end-stage renal disease due to ADPKD with PLD. Because of recurring hepatic cyst infections, he had sustained high levels of C-reactive protein. Regarding the mild consciousness disorder, a diagnosis of hepatic encephalopathy was made based on an elevation of serum ammonia without any other abnormal liver function tests. Several days after his admission, hepatobiliary enzymes elevated, and acute liver failure progressed. Enhanced abdominal computed tomography suggested the possibility of complete occlusion of the portal vein by a thrombus. Based on an absence of obvious portosystemic collaterals, a diagnosis of APVT was made. The patient died 19 days after admission. Patients with PLD with repeated cystic infections have been seen to develop liver failure, and APVT formation may be one cause of the rapid progression of fatal liver failure. In conclusion, this is the first paper to report on the involvement of APVT in patients with PLD.

Renal histopathological findings of retinal vasculopathy with cerebral leukodystrophy.

Retinal vasculopathy with cerebral leukodystrophy (RVCL) is a rare autosomal dominant systemic microvascular disease. Neurological disorders and visual disturbance are highlighted as manifestations of RVCL; however, there are few reports focused on nephropathy. Herein, we describe detailed renal histopathological findings in a daughter and father with RVCL, proven by TREX1 genetic analysis. A kidney biopsy of the daughter, 35-year-old with asymptomatic proteinuria, revealed unique and various glomerular changes. Atypical double contour (not tram track-like) of the capillary wall was widely found, an apparent characteristic finding. Glomerular findings were varied due to a combination of new and old segmental mesangial proliferative changes, mesangiolysis, and segmental glomerulosclerosis-like lesions; these changes may be related to endothelial cell damage. Collapsed tufts were also found and thought to be the result of ischemia due to arterial changes. Glomerular findings in a kidney biopsy of the father revealed similarity to the daughter's glomerulus at a relatively advanced stage, but the degree of variety in the glomerular findings was much less. Kidney biopsy findings suggesting endothelial cell damage of unknown etiology need to be considered for possible RVCL.

Malignant vaginal melanoma with metastases to the papilla of Vater in a dialysis patient: a case report.

Malignant vaginal melanoma is an extremely rare clinical condition, with less than 150 cases reported to date. A dialysis patient had primary vaginal melanoma with metastases to the papilla of Vater. Gastroduodenoscopy revealed a polypoid tumor. Histological findings revealed vimentin, S-100 protein, HMB45, MelanA-positive sarcoma-like cells. This staining pattern indicated that this tumor was a malignant melanoma of the papilla. Analysis of an autopsy specimen of the papilla of Vater revealed metastasis from the primary vaginal melanoma. Metastasis of a malignant tumor to the gastrointestinal tract, especially to the papilla, is uncommon. Melanoma should be considered in the differential diagnosis of primary gastrointestinal tract malignancy.

Membranoproliferative pattern of glomerular injury associated with complement component 9 deficiency due to Arg95Stop mutation.

BACKGROUND: Arg95Stop mutation of exon 4 in complement component 9 (C9) gene is common in individuals in Japan with C9 deficiency (C9D); however, understanding of the influences of C9D on human glomerulonephritis remains elusive. METHODS: A total of 1288 patients with chronic kidney disease (CKD) were recruited from the hospitals in Niigata prefecture. They were screened for the Arg95Stop mutation of C9 gene by allele-specific PCR. RESULTS: We identified two individuals with C9D among 1,288 CKD patients, a frequency comparable to that of the general Japanese population (0.16%). Case 1 involved a 44-year-old man presenting with nephrotic proteinuria. The hemolytic activity of CH50 was low, and the concentration of C9 was not detected. Sequencing of exon 4 of the C9 gene showed the Arg95Stop mutation. Renal biopsy revealed diffuse global mesangial proliferation with extensive duplication of glomerular capillary walls. Mesangial, subendothelial and subepithelial deposits were noticed with light and electron microscopy. Immunofluorescent study showed predominant mesangial IgA deposition. Case 2 involved a 62-year-old man presenting with proteinuria and hematuria. His CH50 level was decreased. Renal biopsy revealed diffuse global mesangial proliferation with extensive duplication of glomerular capillary walls. Immune deposits were also confirmed. The percentage of C9D among patients with mesangial proliferation and duplication of GBM in this study was 5.1%. CONCLUSION: These results suggested that the lack of membrane attack complex because of an Arg95Stop mutation of the C9 gene predisposed patients to pathognomonic glomerulonephritis.

[Changes in the prognosis for survival of patients with end-stage renal disease (ESRD) treated by hemodialysis].

UNLABELLED: We started dialysis treatment in our institution in 1966, and have improved hemodialysis (HD) treatment through the induction of a biocompatible dialysis membrane, recombinant human erythropoietin, activated vitamin D and purification of the dialysate. We verified improvement of the prognosis for survival of patients with ESRD during this forty-year period, retrospectively. A total of 1,690 patients who began dialysis therapy in our hospital between January 1966 and December 2005 was studied (men: 1,047, women: 643, age: 58.6 +/- 17.4 years. They were divided into four groups (A: patients who started dialysis in the period from 1966 to 1975; n = 280, B: 1976-1985; n = 455, C: 1986-1995; n = 499, D: 1996-2005; n = 456). The mean follow-up period was 8.48 +/- 8.53 years. Of the patients 1,588 were treated with HD, 78 with peritoneal dialysis (PD), and 24 with PD or HD. Age at the initiation of dialysis increased gradually (A: 40.1 +/- 14.2 y-o, B: 53.2 +/- 15.8 y-o, C: 60.0 +/- 16.0 y-o, D: 66.4 +/- 13.8 y-o), and diabetics increased (A: 6.4%, B: 19.5%, C: 25.6%, D: 33.4%). A total of 1,180 patients died; 48.5% of these patients died of cardiovascular disease, 21.3% of infectious disease, and 6.4% of malignancy. Only 13 patients had kidney-transplants. With the Cox proportional hazard model for HD cases, age at the initiation of dialysis, gender, cause of renal disease, and the periods were significant predictors of mortality. The relative risk of mortality compared with that in A was reduced progressively: 0.796 in period B (95% confidence interval [CI]: 0.659-0.961, p = 0.0178), 0.505 in period C (95% CI: 0.409-0.623, p < 0.0001), and 0.286 in period D (95% CI: 0.223-0.366, p < 0.0001). CONCLUSIONS: Although the number of high-aged patients or diabetics with ESRD increased in these 40 years, the survival of the patients with ESRD improved.

Renal function at the time of renal biopsy as a predictor of prognosis in patients with primary AL-type amyloidosis.

BACKGROUND: Amyloid light-chain (AL)-type amyloidosis is a plasma cell disorder with a poor prognosis for survival. Although prognostic factors, such as the number of organs involved and heart function or failure in respond to therapy have been clarified based on studies including a large series of patients, there are large interindividual differences in the prognosis of patients with primary AL-type renal amyloidosis. METHODS: To clarify the prognostic factors of AL-type renal amyloidosis, we retrospectively investigated the clinical manifestations, histopathological data, and prognosis of 21 patients with amyloidosis, who had been diagnosed by renal biopsy. RESULTS: Eleven patients died, at a mean observational time of 21.7 months after renal biopsy, whereas the mean observational time was 51.0 months for the 10 patients who survived. The creatinine clearance rate was significantly higher, and the serum creatinine concentration and the grade of interstitial damage were significantly lower in surviving patients (P < 0.05). The presence of amyloid fibrils in organs other than the kidney did not influence prognosis for survival. However, the intraventricular septum was thinner in surviving patients (P < 0.1). Thirteen patients had undergone melphalan-prednisolone therapy, but it did not affect prognosis for survival. Cox proportional hazard regression analysis revealed that the renal function at the time of diagnosis was a significant and independent prognostic factor for survival. CONCLUSIONS: Our study demonstrated that renal function at the time of biopsy and renal interstitial damage are the best predictors of survival in AL-type renal amyloidosis.

A clinicopathological study on the long-term efficacy of tonsillectomy in patients with IgA nephropathy.

Our study evaluated the clinical efficacy of tonsillectomy on the long-term renal survival in patients with primary IgA nephropathy (IgAN). Forty-six patients underwent tonsillectomy, and 74 patients did not. The mean of follow-up duration of all patients was 197.0+/-29.3 months (61-339 months). The baseline clinical and histological data at renal biopsy were not statistically different between the two groups with and without tonsillectomy. Five (10.9%) of the tonsillectomy group reached end stage renal failure (ESRF), whereas 19 (25.8%) of the non-tonsillectomy group did. The chi-square test between the two groups showed a significant difference (p <0.05). The renal survival of the tonsillectomy group was significantly higher than that of the non-tonsillectomy group by the Kaplan-Meier method with log-rank test (p <0.05). The Cox regression model also revealed that tonsillectomy had a significant favorable impact on the renal survival in long-term follow-up duration (p <0.05). Although our study was done by retrospective analyses, all the results proved that tonsillectomy had significant favorable effects on the long-term renal survival in patients with IgAN.

The efficacy of tonsillectomy on long-term renal survival in patients with IgA nephropathy.

BACKGROUND: Little information has been available until now about the clinical efficacy of tonsillectomy on long-term renal survival of patients with idiopathic immunoglobulin A nephropathy (IgAN). METHODS: To investigate the effect of tonsillectomy on long-term renal survival, we reviewed the clinical course of 118 patients with idiopathic biopsy-diagnosed IgAN from 1973 to 1980. Of those, 48 patients received tonsillectomy and 70 patients did not. The starting point of observation was defined as the time of the diagnostic renal biopsy, and the end point as when requiring the first dialysis. Up to 2001, the mean observation time was 192.9 +/- 74.8 months (48-326 months). Renal survival and impact of covariates were evaluated by Kaplan-Meier analysis and Cox proportional hazards regression model. RESULTS: Age, gender, amount of urinary protein excretion, serum creatinine, serum IgA, blood pressure, and histopathologic findings at the time of renal biopsy and treatments during the observation period were not significantly different between patients with and without tonsillectomy. Five (10.4%) of the patients with tonsillectomy and 18 (25.7%) of the patients without tonsillectomy finally required dialysis therapy (chi-square test, P = 0.0393). By Kaplan-Meier analysis, renal survival rates were 89.6% and 63.7% at 240 months in the patients with and without tonsillectomy, respectively, and were significantly different (log-rank test, P = 0.0329). In the multivariate Cox regression model, tonsillectomy (hazard ratio, 0.22; 95% CI, 0.06 to 0.76; P = 0.0164) had a significant effect on renal outcome. CONCLUSION: These results indicate that tonsillectomy has a favorable effect on long-term renal survival in patients with IgAN.

Patient with diffuse mesangial and endocapillary proliferative glomerulonephritis with hypocomplementemia and elevated anti-streptolysin O treated with prednisolone, angiotensin-converting enzyme inhibitor, and angiotensin II receptor antagonist.

A 24-year-old woman was admitted to Toyosaka Hospital with proteinuria, hematuria, lymphopenia, hypocomplementemia, positive anti-nuclear antibody (ANA), and elevation of anti-streptolysin O (ASO). Renal biopsy specimen revealed diffuse mesangial and endocapillary glomerulonephritis with crescent formation and duplication of the capillary loop on light microscopic examination. Mild to moderate proliferation of mesangial matrix and cells were observed. On immunofluorescence (IF) examination, deposition of IgG, IgA, IgM, C1q, C3, and C4 to the mesangium and capillary wall were observed. By electron microscopy (EM), mesangial, subendothelial, and subepithelial deposits were recognized. However, microtubular structure in glomerular endothelial cells, fingerprint structures, and circumferential mesangial interposition were not observed by EM. The patient was referred to our hospital, but there was no change in her proteinuria 3 weeks after admission. The elevation of ASO, hypocomplementemia, and endocapillary proliferation suggested acute glomerulonephritis, while lymphocytopenia, positive ANA, the persistent hypocomplementemia, and various deposits detected by IF and EM suggested lupus nephritis; however, she did not fulfill the classification criteria of systemic lupus erythematosus. We started prednisolone (40 mg/day) with the diagnosis of chronic glomerulonephritis revealing diffuse mesangial and endocapillary proliferative glomerulonephritis, but it was not effective for the proteinuria. Quinapril (10 mg/day) and losartan (25 to 50 mg/day) were administered and the proteinuria decreased. It is possible that this use of an angiotensin converting-enzyme inhibitor and an angiotensin II receptor antagonist was effective in reducing the proteinuria in this patient.

A(-20)C polymorphism of the angiotensinogen gene and progression of IgA nephropathy.

BACKGROUND: The M235T polymorphism of the angiotensinogen gene (AGT) is associated with an increased risk of primary hypertension, which may then lead to progressive renal disease. Recent studies showed that nucleotide substitution in the 5' upstream core promoter region of AGT affects the basal transcription rate of the gene. METHODS: To evaluate the role of AGT polymorphisms in the progression of IgA nephropathy (IgAN), we analyzed the association of A(-20)C and M235T polymorphisms with renal prognosis in histologically-proven IgAN patients using the Kaplan-Meier method and Cox proportional hazards regression model. RESULTS: The incidence of hypertension during the course was associated with T235, but not with C(-20). The renal survival rate for 137 patients with creatinine clearance (C(Cr)) of 70 mL/min or greater at the time of renal biopsy, and follow-up time of two years or more was significantly lower in the patients with C(-20) (P = 0.008). The Cox proportional hazards regression model showed an increased hazard ratio (HR) for urinary protein (more than 2 g/day) of 28.3 (95% CI, 7.3 to 109.8; P < 0.001), hypertension at the time of renal biopsy of 4.6 (95% CI, 1.8 to 11.9; P = 0.002), and C(-20) of 3.6 (95% CI, 1.5 to 8.7; P = 0.004). CONCLUSION: This work provides evidence that the C(-20) polymorphism of AGT, a subset of T235 alleles, is associated with progression of renal dysfunction in IgAN.