Glomerular expression and urinary excretion of fatty acid-binding protein 4 in IgA nephropathy

BACKGROUND

Fatty acid-binding protein 4 (FABP4) is secreted from adipocytes and macrophages in adipose tissue and acts as an adipokine. It has recently been reported that FABP4, but not liver-type FABP (L-FABP/FABP1), is also expressed in injured glomerular endothelial cells and infiltrating macrophages in the glomerulus and that urinary FABP4 (U-FABP4) is associated with proteinuria and kidney function impairment in nephrotic patients. However, the link between glomerular FABP4 and U-FABP4 has not been fully addressed in IgA nephropathy (IgAN).

METHODS

We investigated the involvement of FABP4 in human and mouse IgAN.

RESULTS

In patients with IgAN (n = 23), the ratio of FABP4-positive area to total area within glomeruli (G-FABP4-Area) and U-FABP4 were positively correlated with proteinuria and were negatively correlated with eGFR. In 4-28-week-old male grouped ddY mice, a spontaneous IgAN-prone mouse model, FABP4 was detected in glomerular endothelial cells and macrophages, and G-FABP4-Area was positively correlated with urinary albumin-to-creatinine ratio (r = 0.957, P < 0.001). Endoplasmic reticulum stress markers were detected in glomeruli of human and mouse IgAN. In human renal glomerular endothelial cells, FABP4 was induced by treatment with vascular endothelial growth factor and was secreted from the cells. Treatment of human renal glomerular endothelial cells or mouse podocytes with palmitate-bound recombinant FABP4 significantly increased gene expression of inflammatory cytokines and endoplasmic reticulum stress markers, and the effects of FABP4 in podocytes were attenuated in the presence of an anti-FABP4 antibody.

CONCLUSION

FABP4 in the glomerulus contributes to proteinuria in IgAN, and U-FABP4 level is a useful surrogate biomarker for glomerular damage in IgAN.

Successful renal recovery from multiple myeloma-associated crystalline light chain cast nephropathy and accompanying acute kidney injury with early use of bortezomib-based therapy: a case report and literature review

Crystalline light chain cast nephropathy is a rare distinct morphologic variant of light chain cast nephropathy which is the most common renal lesion associated with multiple myeloma. It is often related to high myeloma tumor burden, severe acute kidney injury, and an unfavorable prognosis. A 79-year-old Japanese man was referred to our medical center with anemia, proteinuria, and acute exacerbation of the serum creatinine accompanying anuria. A renal biopsy showed crystalline cast filling the tubular lumens, injured tubular cells, and inflammatory cells infiltration of interstitium. Serum and urine immunofixation detected a monoclonal protein (IgA-λ and Bence-Jones Protein-λ, respectively), and bone marrow examination observed 64% of plasma cells. IgA-λ type multiple myeloma-associated crystalline light chain cast nephropathy and accompanying acute kidney injury were confirmed. Hydration and emergency hemodialysis were immediately introduced, and the treatment with bortezomib and dexamethasone was initiated. The patient showed successful recovery in renal manifestations. We suggest that early use with bortezomib-based therapy should be considered for patients with acute kidney injury caused by multiple myeloma-associated crystalline light chain cast nephropathy.

Seasonal variation of serum 25-hydroxyvitamin D level in hemodialysis patients in the northernmost island of Japan

BACKGROUND

Serum vitamin D level shows a seasonal variation, being lower in winter than in summer in healthy subjects. The aim of this study was to determine whether there is presence of such a seasonal variation in hemodialysis patients.

METHODS

A total of 102 patients on hemodialysis were enrolled in February 2017 (winter) for analyses of serum levels of 25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D [1,25(OH)₂D] and treatments for chronic kidney disease-mineral and bone disorder (CKD-MBD). The examinations were repeated in August 2017 (summer). After exclusion of patients with malignancy, loss of follow-up and missing data, 78 patients contributed to the analyses.

RESULTS

Serum level of 25(OH)D, but not that of 1,25(OH)₂D, was significantly lower in winter (14.0 ng/mL) than in summer (15.5 ng/mL), though there was no significant difference in regimen for CKD-MBD treatment including vitamin D receptor activators (VDRAs) between the two seasons. Serum intact parathyroid hormone level tended to be higher and alkaline phosphatase was significantly higher in winter than in summer. Linear mixed-effects model analysis showed that level of 25(OH)D, but not that of 1,25(OH)₂D, was significantly associated with season (winter and summer) after adjustment of age, sex, dialysis vintage, albumin level and use of drugs for CKD-MBD.

CONCLUSION

Serum 25(OH)D has a seasonal variation, being lower in winter than in summer, independent of CKD-MBD treatment including treatment with VDRAs in Japanese hemodialysis patients. The impact of the seasonal variation on risk of vitamin D deficiency and its effect on prognosis remain to be investigated.

Association Between Renal Adverse Effects and Mortality in Patients With Hepatocellular Carcinoma Treated With Lenvatinib

BACKGROUND/AIM

Lenvatinib, a multitargeted tyrosine kinase inhibitor, was recently approved for hepatocellular carcinoma (HCC) treatment in Japan; however, the association between proteinuria following lenvatinib administration in HCC patients and early mortality is unknown. This study aimed to examine the association between nephrotic-range proteinuria (NRP) and mortality and evaluated the risk factors for NRP among Japanese HCC patients treated with lenvatinib.

PATIENTS AND METHODS

We retrospectively analyzed 45 consecutive patients receiving lenvatinib from 2018-2019. Primary outcome was overall survival. Cox proportional hazards regression was used to evaluate the association between NRP and overall survival. Logistic regression analyses were used to identify NRP risk factors after lenvatinib initiation.

RESULTS

The median age was 66 years, 56% were women, and 20% had pre-existing proteinuria. During a 1-year median follow-up, 24 died, and 5 developed NRP. Univariable logistic regression showed that pre-existing proteinuria was associated with higher NRP risk; however, the association was not significant after covariate adjustment. Following multivariable Cox analysis, NRP did not affect overall survival in advanced HCC patients receiving lenvatinib.

CONCLUSION

Urinalysis findings should be monitored regularly in patients receiving lenvatinib because NRP incidence was comparable to that of prior studies. Identifying the predictors of NRP after lenvatinib initiation warrants further investigation.

Light Chain Deposition Disease Diagnosed Using Computed Tomography-Guided Kidney Biopsy

Light chain deposition disease (LCDD) is characterized by the deposition of monoclonal immunoglobulin light chains in the kidney, which can cause end-stage kidney disease if not treated. While kidney biopsy is required for definitive diagnosis, choosing an appropriate biopsy method may be problematic when examining patients with atrophic kidneys. A 66-year-old Japanese man was referred to our institution with a three-month history of leg edema. Clinical investigations revealed proteinuria levels of 7.5 g/day. CT-guided percutaneous kidney biopsy was selected as the biopsy method because atrophic kidneys were poorly visualized on ultrasonography. Kidney biopsy revealed nodular glomerulosclerosis, exclusive deposition of the κ chain, and powdery electron-dense deposits, all of which were indicative of LCDD. Bence-Jones protein was detected in the urine. The patient also had an abnormal serum-free light chain ratio. Bone marrow biopsy revealed multiple myeloma; therefore, the patient was diagnosed to have LCDD with multiple myeloma. The patient was treated with daratumumab, bortezomib, cyclophosphamide, and dexamethasone. After a one-year follow-up, the patient had hematological and renal responses without any treatment-related adverse effects. Our case demonstrates the effectiveness of daratumumab as a treatment for LCDD with nephrotic-range proteinuria. Additionally, we suggest that CT-guided kidney biopsy should be considered as a diagnostic test in patients with kidney atrophy when making a definitive diagnosis.

Association between diuretic administration before diagnosis and incidence of acute kidney injury in patients with minimal change disease: A single-center observational study

We examined the association between diuretic administration before the diagnosis of minimal change disease and the incidence of acute kidney injury. Moreover, we examined whether the use of diuretics affected the time to complete remission in adults with such disease.The present study was a single-center, retrospective, observational cohort study. We included 107 patients with biopsy-proven minimal change disease who were treated at a tertiary referral center in Japan between January 1, 2000 and March 31, 2019. All biopsy specimens were examined by a board-certified renal pathologist. The patients were considered to have minimal change disease when the kidney biopsy specimen had no glomerular lesions or only mild focal mesangial prominence (not exceeding 3 or 4 cells per segment) by light microscopy and/or foot process effacement by electron microscopy. Logistic regression and Kaplan-Meier curve analyses were performed, comparing the data of patients who received diuretics or not.The median age was 47 (28-66) years, 52% of patients were women, and the median proteinuria dosage was 8.3 (5.3-11.2) g/d. When minimal change disease was diagnosed, 27% of patients were taking diuretics. Within 30 days after the diagnosis, acute kidney injury occurred in 27% of patients. On multivariable logistic regression analysis, the use of diuretics was significantly associated with a higher risk of acute kidney injury. The use of diuretics was also associated with a longer time to complete remission.Diuretic administration can be associated with an elevated acute kidney injury risk and longer remission time in adult patients with newly diagnosed minimal change disease.

Selective immunoglobulin M deficiency complicated by systemic lupus erythematosus and antiphospholipid syndrome: a case report and review of literature

Selective immunoglobulin M deficiency (SIgMD) is the isolated absence of serum immunoglobulin M (IgM) with normal levels of other serum immunoglobulins. SIgMD is associated with infections and autoimmune diseases. While there are few reports on SIgMD complicated by systemic lupus erythematosus (SLE), there are no reports on SIgMD complicated by SLE and antiphospholipid syndrome (APS); we present the first report of this kind. A 61-year-old Japanese woman presented with microscopic hematuria and proteinuria. Clinical investigations revealed an elevated serum creatinine level, an undetectable serum IgM level, and seropositivity of antinuclear antibody, anti-Smith antibody, and double-stranded DNA antibody. Radiological investigations were unremarkable. Renal biopsy revealed focal and segmental mesangial cell proliferation; thickened glomerular capillary walls; and IgG, IgA, C3, and C1q deposition, which indicated class III (A/C) lupus nephritis (Renal Pathology Society/International Society of Nephrology classification). Furthermore, anti-CLβ2GP1 antibody positivity and deep vein thrombosis were noted, which fulfilled the revised Sapporo classification criteria for the diagnosis of APS. Thus, she was diagnosed with SIgMD complicated by SLE and APS. The patient was treated with prednisolone, mycophenolate mofetil, and warfarin. After a 1-year follow-up, she achieved clinical remission of SLE and APS without infectious complications; however, the serum IgM level remained undetectable. In conclusion, SIgMD can be complicated by autoimmune disorders. Although rare, we recommend that SLE and APS be considered in patients with SIgMD who present with hematuria, proteinuria, and deep vein thrombosis. We also recommend measuring the titers of antinuclear antibodies, double-stranded DNA antibodies, and anti-CLβ2GP1 antibodies.

Intradialytic exercise in the treatment of social frailty: a single-center prospective study-preliminary results during the unexpected COVID-19 pandemic

Background

Social frailty—the lack of a connection to society and infrequent social activities—has been reported to be associated with future declines in physical function in elderly individuals. This study aimed to evaluate both the association of social frailty with the physical function and the efficacy of intradialytic exercise as a therapy for social frailty among hemodialysis patients.

Methods

All 16 outpatient hemodialysis patients in the hemodialysis department of a single medical center were enrolled in this single-center prospective single-arm interventional study. Patients received five questions which asked about going out infrequently, lack of visiting friends, feeling unhelpful to friends or family, living alone, and lack of talking with someone. Those to whom two or more of the above were applicable were categorized as socially frail. All patients were placed into exercise therapy to be performed during their thrice-weekly hemodialysis visits. Participants’ physical function (walking speed), muscle strength (grip strength), muscle mass (appendicular skeletal muscle mass index), and social frailty were evaluated at baseline and after 3 months of therapy.

Results

Four (25%) of the 16 participants (median age 71.5 years, 8 women) were categorized as being socially frail. In comparison to the non-socially frail group (non-SF), the socially frail group (SF) had a significantly lower walking speed (0.70 ± 0.12 m/s vs 1.15 ± 0.26 m/s, p = 0.005) and significantly worse performance on the Short Physical Performance Battery. Three months of intradialytic exercise therapy significantly improved their walking speed, from 1.04 ± 0.30 m/s to 1.16 ± 0.29 m/s (p = 0.003). intradialytic exercise therapy significantly improved walking speed in both the SF group and the non-SF group. The 2019 coronavirus disease pandemic unexpectedly occurred in the middle of the intervention period of this study, and although it was not statistically significant, the number of socially frail individuals among our participants increased to seven (43.8%, p = 0.248).

Conclusions

Social frailty was associated with reduced physical function among hemodialysis patients. Intradialytic exercise therapy improved physical function regardless of the presence of social frailty.

Trial registration

UMIN-CTR, UMIN-CTR000038313. Registered November 1, 2019, https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000043639.

Incidence and risk factors of acute kidney injury, and its effect on mortality among Japanese patients receiving immune check point inhibitors: a single-center observational study

BACKGROUND

Immune checkpoint inhibitors (ICPis) are associated with multi-organ immune-related adverse effects. Here, we examined the incidence rate, recovery rate, and risk factors of acute kidney injury complicated with ICPis (ICPi-AKI) and evaluted the association between ICPi-AKI and mortality in Japanese patients.

METHODS

We analyzed 152 consecutive patients receiving ICPis between 2015 and 2019. A logistic regression analysis was performed to identify risk factors for ICPi-AKI incidence and Cox regression analysis was performed to evaluate the association between ICPi-AKI and mortality.

RESULTS

The mean patient age was 67 ± 10 years, with the median baseline serum creatinine level of 0.78 mg/dL. Twenty-seven patients (18%) developed ICPi-AKI, and 19 (73%) of them recovered. Pembrolizumab use and liver diseases were significant risk factors for the ICPi-AKI incidence. During the follow-up, 85 patients (59%) died, 17 patients (63%) with ICPi-AKI and 68 (54%) patients without ICPi-AKI, respectively. The ICPi-AKI incidence was not independently associated with mortality (adjusted hazard ratio, 0.85; 95% confidence intervals, 0.46-1.61).

CONCLUSIONS

Our finding suggest that pembrolizumab use and liver diseases are associated with a higher risk of ICPi-AKI development, but ICPi-AKI did not affect mortality. Future multi-center studies are needed to develop optimal management and prevention strategies for this complication in patients receiving ICPis.

Clinical and immunologic characteristics of Japanese patients with anti-glomerular basement membrane disease: case reports and literature review

Background

Clinical studies of anti-glomerular basement membrane (GBM) disease were limited because of the low incidence. We aimed to report the characteristics, treatments, and outcomes of patients with anti-GBM disease at a tertiary reference medical center in Japan and review the literature of mortality in patients with anti-GBM disease.

Case presentation

Case 1 was a 72-year-old Japanese man that was referred with worsening of the serum creatinine (from 1.1 to 27.3 mg/dL). Anti-GBM disease was confirmed by renal biopsy, and treatments with oral prednisolone and plasmapheresis were initiated. Although his anti-GBM antibody decreased (from 476 to 18 units/mL) after the treatments, the patient died from lung abscess. Case 2 was a 32-year-old Japanese man that presented with fever and macroscopic hematuria. At presentation, his serum creatinine was 4.2 mg/dL, and anti-GBM antibody was 265 units/mL. Renal biopsy confirmed the diagnosis of anti-GBM disease, and intensive treatments with plasmapheresis and methyl prednisolone were started, followed by oral prednisolone. Living-donor kidney transplantation was performed because his anti-GBM antibody had remained undetectable for 1 year after diagnosis. In the main text, clinicopathological characteristics of 12 patients with anti-GBM disease at our institution were summarized.

Conclusions

We found that the 1-year survival rate of patients with anti-GBM disease was 88% in our cohort, which was comparable to previous studies. Multicenter, nationwide studies are expected to evaluate prognosis of Japanese patients with this rare entity.

Association of blood pressure with mortality in hemodialysis patients with a tunneled cuffed catheter: A single-center observational study

The use of tunneled cuffed catheters (TCCs) for permanent blood access is increasing as the hemodialysis population ages. However, the higher mortality and complication rates associated with their use have been significant concerns. This single-center observational cohort study aimed to investigate clinical factors affecting mortality and complications in Japanese hemodialysis patients with a TCC.We enrolled 64 consecutive patients receiving hemodialysis through a TCC between 2012 and 2019. The primary outcome was all-cause mortality and the secondary outcome was the incidence of catheter-related complications at 2 years. Cox proportional hazards models were used to examine variables associated with these outcomes.At 2 years, death from any cause and catheter-related complications occurred in 27/64 (42%) and 23/64 (36%) patients, respectively. There were 14 bacteremia events, 7 catheter obstructions, and 8 instances of restricted blood flow. Multivariate analysis showed that systolic blood pressure (SBP) < 100 mm Hg at the time of catheter insertion was associated with higher all-cause mortality (hazard ratio, 2.59; 95% confidence interval, 1.05-6.41) and catheter-related complications (hazard ratio, 2.57; 95% confidence interval, 1.52-22.2). The Kaplan-Meier analyses also showed that patients with SBP <100 mm Hg had higher mortality (P = .001) and a higher incidence of catheter-related complications (P = .0068).SBP <100 mm Hg at the time of catheter insertion is associated with mortality and catheter-related complications in hemodialysis patients using a TCC. Further multi-center studies are required to validate our results.

Unusual etiology of persistent fever after urinary tract infection: Papillary renal cell carcinoma

This manuscript presents a case report of type 2 papillary renal cell carcinoma presenting with persistent fever and abdominal tenderness after treatment for urinary tract infection. The purpose of this article is to aid physicians in understanding that papillary renal cell carcinomas should be considered in patients with a persistent fever after urinary tract infection and computed tomography was useful to diagnose this entity.

Developments in the Histopathological Classification of ANCA-Associated Glomerulonephritis

BACKGROUND AND OBJECTIVES

The histopathologic classification for ANCA-associated GN distinguishes four classes on the basis of patterns of injury. In the original validation study, these classes were ordered by severity of kidney function loss as follows: focal, crescentic, mixed, and sclerotic. Subsequent validation studies disagreed on outcomes in the crescentic and mixed classes. This study, driven by the original investigators, provides several analyses in order to determine the current position of the histopathologic classification of ANCA-associated GN.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A validation study was performed with newly collected data from 145 patients from ten centers worldwide, including an analysis of interobserver agreement on the histopathologic evaluation of the kidney biopsies. This study also included a meta-analysis on previous validation studies and a validation of the recently proposed ANCA kidney risk score.

RESULTS

The validation study showed that kidney failure at 10-year follow-up was significantly different between the histopathologic classes (P<0.001). Kidney failure at 10-year follow-up was 14% in the crescentic class versus 20% in the mixed class (P=0.98). In the meta-analysis, no significant difference in kidney failure was also observed when crescentic class was compared with mixed class (relative risk, 1.15; 95% confidence interval, 0.94 to 1.41). When we applied the ANCA kidney risk score to our cohort, kidney survival at 3 years was 100%, 96%, and 77% in the low-, medium-, and high-risk groups, respectively (P<0.001). These survival percentages are higher compared with the percentages in the original study.

CONCLUSIONS

The crescentic and mixed classes seem to have a similar prognosis, also after adjusting for differences in patient populations, treatment, and interobserver agreement. However, at this stage, we are not inclined to merge the crescentic and mixed classes because the reported confidence intervals do not exclude important differences in prognosis and because an important histopathologic distinction would be lost.

Clinical and genetic characterization of nephropathy in patients with nail-patella syndrome

Nail-patella syndrome (NPS) is a multi-system disorder characterized by hypoplastic nails, hypoplastic patella, skeletal deformities, and iliac horns, which is caused by heterozygous variants of LMX1B. Nephropathy ranging from mild urinary abnormality to end-stage renal disease occurs in some individuals with NPS. Because of the low prevalence of NPS and the lack of longitudinal studies of its kidney involvement, the clinical, pathological, and genetic features characterizing severe nephropathy remain unclear. We conducted a Japanese survey of NPS with nephropathy, and analyzed their clinical course, pathological features, and factors associated with severe renal phenotype. LMX1B gene analysis and luciferase reporter assay were also performed. Among 13 NPS nephropathy cases with genetic validation, 5 patients who had moderate-to-massive proteinuria progressed to advanced chronic kidney disease or end-stage renal disease. Pathological findings in the early phase did not necessarily correlate with renal prognosis. Variants associated with deteriorated renal function including a novel variants were confined to the N-terminal region of the LIM domain and a short sequence in the LMX1B homeodomain, which were distinct from reported variants found in isolated nephropathy without extrarenal manifestation (LMX1B-associated nephropathy). Luciferase reporter analysis demonstrated that variants in patients with severe renal phenotype caused haploinsufficiency, but no dominant-negative effects on promoter activation. A distinct proportion of NPS nephropathy patients progressed to end-stage renal disease in adolescence or young adulthood. Patients with moderate or severe proteinuria, especially those with variants in specific regions of LMX1B, should be monitored for potential deterioration of renal function.

Association between Functional Independence Measure and mortality in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis: A single-center observational study

OBJECTIVES

Previous studies have identified several predictors of mortality in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). However, functional dependence as a predictor of mortality has never been reported. In this study, we investigated whether Functional Independence Measure (FIM) was associated with mortality in AAV patients.

METHODS

We analyzed 52 adults with biopsy-proven AAV in Teine Keijinkai Medical Center between January 2000 and March 2019. Adjusted Cox regression analyses were conducted to evaluate the association between three FIM-based groups and all-cause mortality. Estimates were calculated as hazard ratios with 95% confidence intervals (95% CIs).

RESULTS

During a median follow-up of 2.3 years (interquartile range, 0.7-4.6 years), death occurred in 15 patients (29%). Compared to the highest-FIM group (91-126 points), the adjusted hazard ratios for the intermediate- (55-90 points) and lowest-FIM (18-54 points) groups were 3.59 (95% CIs, 0.40-32.0) and 15.7 (95% CIs, 2.07-119) for all-cause mortality, respectively. In addition, the lower-FIM groups were associated with higher mortality (p=.0179).

CONCLUSION

This study suggested that the FIM score is a predictor of all-cause mortality in AAV patients. Future studies will have to investigate whether FIM assessment leads to better outcomes.

Gastrointestinal bleeding is associated with renal prognosis in adult patients with IgA vasculitis with nephritis

Background

Although the prediction of renal prognosis in patients with IgA vasculitis with nephritis (IgAVN) is important, the association between gastrointestinal bleeding (GIB) and its renal prognosis is unknown. This study investigated the effect of GIB on the progression to end‐stage kidney disease (ESKD) in patients with IgAVN.

Methods

We compared the clinicopathological findings at diagnosis, therapy, and clinical outcomes between 10 patients with GIB and 20 patients without GIB in 30 patients with IgAVN aged ≥18 years at the renal biopsy. The primary outcome was the incidence of ESKD. Secondary outcomes included clinical remission and all‐cause mortality. The outcomes and factors affecting the progression to ESKD were evaluated using the Kaplan‐Meier method with log‐rank test and Cox proportional hazards models.

Results

End‐stage kidney disease, clinical remission, and deaths from any related cause occurred in 6, 17, and 2 patients, respectively. In Kaplan‐Meier analyses, the GIB group showed a higher incidence of ESKD (50% vs 5%, P = .003) and a lower incidence of clinical remission (20% vs 75%, P = .003). Although the numbers were not statistically significant, this group tended to have a greater number of deaths than the non‐GIB group (7% vs 0%, P = .07). In a multivariable Cox model adjusted for hypertension and urinary proteinuria, GIB could not demonstrate a significant association with ESKD (hazard ratio, 4.51; 95% confidence interval, 0.39‐52.7; P = .23).

Conclusion

IgAVN with GIB has worse renal outcome, but GIB does not have a statistically significant association with progression to ESKD.

Immunoglobulin A nephropathy secondary to Wilson's disease: a case report and literature review

Immunoglobulin A nephropathy is the most common primary glomerulonephritis worldwide, and it can be associated with liver disease. However, cases of Immunoglobulin A nephropathy secondary to Wilson's disease are very rare. A 20-year-old Japanese man presented with microscopic hematuria, proteinuria, and renal dysfunction. A renal biopsy showed mesangial cell proliferation, immunoglobulin A deposition, and electron-dense deposit in the mesangial areas, all of which are consistent with Immunoglobulin A nephropathy. Computed tomography of the abdomen showed liver atrophy and splenomegaly, and the diagnosis of Wilson's disease was confirmed with decreased serum ceruloplasmin levels, increased urinary copper excretion, Kayser-Fleischer rings and copper deposition in the liver biopsy. The patient was treated successfully with trientine hydrochloride and zinc acetate and showed improvement in renal manifestations. Wilson's disease is a rare cause of secondary Immunoglobulin A nephropathy. We recommend that Wilson's disease should be considered the cause of secondary Immunoglobulin A nephropathy in juvenile patients with hematuria, proteinuria, and splenomegaly and suggest measuring the serum ceruloplasmin concentrations, urinary copper excretion, and evaluating Kayser-Fleischer rings in these patients.

Palmoplantar pustulosis and IgA nephropathy

We present a case of IgA nephropathy complicated with palmoplantar pustulosis. The skin lesion improved with tonsillectomy. The purposes of this article were to aid physicians in understanding that (a) IgA nephropathy should be considered in patients with palmoplantar pustulosis and (b) patients with these diseases should be referred to otolaryngology specialists for tonsillectomy.

Anti-glomerular basement membrane disease accompanied by systemic lupus erythematosus presenting central nervous system involvement

We report a case of rapidly progressive glomerulonephritis caused by anti-glomerular basement membrane (GBM) disease accompanied by systemic lupus erythematosus (SLE) presenting central nervous system involvement in a 32-year-old Japanese male. He was admitted to our hospital because of a 3-week history of fever and rapidly failing renal function requiring hemodialysis (HD). Laboratory tests showed anti-GBM antibody elevation with a value of 16,385 units/ml. On day 85, he had generalized tonic-clonic seizure. Brain magnetic resonance T2 Flair imaging showed multiple high intensity lesions in a broad area. We made a diagnosis of central nervous system involvement in SLE based on positivity for antinuclear and anti-DNA antibodies, hypocomplementemia, and discoid skin rash. After combined therapy consisting of plasma exchange, HD, and steroid pulse, the patient made a good recovery without any residual neurological sequelae, though kidney dysfunction requiring maintenance HD remained. Anti-GBM antibody finally became undetectable on the 144th hospital day.

Stable neutral radicals of planar N2O2-type dipyrrin platinum complexes: hybrid radicals of the delocalized organic π-orbital and platinum d-orbital

Neutral radicals of N2O2-dipyrrin platinum complexes were synthesized by the reaction of dipyrrin ligands with PtCl2(cod) and successive one-electron oxidation. The radicals are very stable even under aerobic and ambient conditions. X-ray crystallographic analysis revealed the stacking array of the planar dipyrrin complex moieties. The ESR signals were broadened and significantly downfield shifted. The absorption spectra exhibited NIR bands. These results indicated a delocalized radical character with a contribution by the platinum d-orbital.

Optimal blood pressure in patients with peripheral artery disease following endovascular therapy

This study examined the associations between blood pressure (BP) and event incidence to define optimal BP after endovascular therapy (EVT) in patients who underwent EVT. BP was monitored every 6 months for 5 years, and the patients were divided into two groups by average BP: ≥ 140/90 mmHg and < 140/90 mmHg. The association of BP with several events was examined. Although no significant differences in total mortality were observed between the groups, restenosis rates were significantly higher among patients who did not achieve target BP (36.2%) than among those who did (18.2%) (p < 0.01). The percentage of patients with glycosylated haemoglobin > 7.0% was significantly higher among those who did not achieve target BP in the restenosis group (42.9%) than in the other group (10.8%) (p < 0.01). In the restenosis group, there was a significantly higher percentage of patients taking metformin (p < 0.01) than in the other group. Metformin seemed to be administered to patients with more severe diabetes mellitus. In conclusion, it is important to manage hypertension and diabetes to prevent restenosis after EVT.

[The Impact That SPECT Collection Angle and Collection Orbit Gives to an Image: Myocardial Digital Phantom Study]

PURPOSE

We evaluated the effect that collection angle and collection orbit condition gave to an image quantitatively by simulating the single photon emission computed tomography (SPECT) system.

METHOD

Using the Software Package of the Nuclear Medicine Data Processor for Research, we performed making of the myocardial digital phantom, three ways of different simulation of the collection angle and collection orbit, and making of reference of the uniform picture element level. We calculated NMSE for uniformity evaluation and calculated myocardial thickness full width at half maximum (FWHM) for a spatial resolution evaluation.

RESULTS

360 degrees circular orbit collection had best uniformity. 180 degrees noncircular orbit collection had best spatial resolution.

CONCLUSION

By using the digital phantom, we focused on only collection angle and collection orbit condition, and focused on two indexes of the uniformity and the spatial resolution and were able to show a quantitative index.

Urinary angiotensin-converting enzyme 2 in hypertensive patients may be increased by olmesartan, an angiotensin II receptor blocker

BACKGROUND

Angiotensin-converting enzyme 2 (ACE2) is highly expressed in the kidney and converts angiotensin (Ang) II to Ang-(1-7), a renoprotective peptide. Urinary ACE2 has been shown to be elevated in patients with chronic kidney disease. However, the effects of antihypertensive agents on urinary ACE2 remain unclear.

METHODS

Of participants in the Tanno-Sobetsu cohort study in 2011 (n = 617), subjects on no medication (n = 101) and hypertensive patients treated with antihypertensive agents, including the calcium channel blockers amlodipine and long-acting nifedipine; the ACE inhibitor enalapril; and the Ang II receptor blockers losartan, candesartan, valsartan, telmisartan, and olmesartan, for more than 1 year (n = 100) were enrolled, and urinary ACE2 level was measured.

RESULTS

Glucose and hemoglobin A1c were significantly higher in patients treated with enalapril, telmisartan or olmesartan than in the control subjects. Urinary albumin-to-creatinine ratio (UACR) was significantly higher in patients treated with enalapril than in the control subjects. Urinary ACE2 level was higher in the olmesartan-treated group, but not the other treatment groups, than in the control group. Urinary ACE2 level was positively correlated with systolic blood pressure (r = 0.211; P = 0.003), UACR (r = 0.367; P < 0.001), and estimated salt intake (r = 0.260; P < 0.001). Multivariable regression analysis after adjustment of age, sex, and the correlated indices showed that the use of olmesartan was an independent predictor of urinary ACE2 level.

CONCLUSIONS

In contrast with other antihypertensive drugs, olmesartan may uniquely increase urinary ACE2 level, which could potentially offer additional renoprotective effects.

Tubulointerstitial nephritis and uveitis syndrome complicated by IgA nephropathy and Graves' disease: a case report

Introduction

Tubulointerstitial nephritis and uveitis syndrome is a disorder characterized by a combination of acute tubulointerstitial nephritis and uveitis. Immunoglobulin A nephropathy is defined by the presence of immunoglobulin A deposits in glomerular mesangial areas. In this report, we describe a rare case of tubulointerstitial nephritis and uveitis syndrome complicated by immunoglobulin A nephropathy and Graves’ disease, which was successfully treated with corticosteroids. To the best of our knowledge, this is the first time such a case has been documented since tubulointerstitial nephritis and uveitis syndrome was first described.

Case presentation

A 64-year-old Japanese woman presented with tubulointerstitial nephritis and uveitis syndrome accompanied by immunoglobulin A nephropathy and Graves’ disease. She had renal dysfunction, proteinuria, and hematuria. Two weeks after her admission, she developed anterior chamber uveitis. She received corticosteroids, resulting in significant clinical improvement.

Conclusion

Tubulointerstitial nephritis and uveitis syndrome is a relatively uncommon cause of tubulointerstitial nephritis. Clinicians should recognize that tubulointerstitial nephritis and uveitis syndrome with immunoglobulin A nephropathy can occur in the presence of Graves’ disease. Additionally, this report may provide important clues in terms of the management of a concomitant case of these diseases.

Abstract 550: Plasma Angiotensin-(1-12) Level Is Elevated And Correlates With Proteinuria In Patients With Chronic Kidney Diseases

Angiotensin-(1-12) [Ang-(1-12)], C-terminally extended form of Ang I, is an alternative precursor of Ang II. Although angiotensinogen, a precursor of both Ang I and Ang-(1-12), is reportedly one of markers of kidney disease, little is known about role of Ang-(1-12) in pathological status especially in human. To address this issue, we measured plasma and urinary Ang-(1-12) by enzyme immunoassay in 4 healthy volunteers and 15 patients with biopsy-proven chronic kidney diseases (CKD). CKD group included minor glomerular abnormality (n=3), IgA nephropathy (n=8), minimal change nephritic syndrome (n=4). Ang-(1-12) level was 55-fold higher in urine than in plasma (Figure; 4.12±1.55 vs 0.075±0.006 ng/mL, P<0.05). Neither plasma Ang-(1-12) nor urinary Ang-(1-12) was correlated with blood pressure. Plasma Ang-(1-12) was positively correlated with urinary protein and tended to be negatively correlated with estimated glomerular filtration ratio (eGFR; Figure). Plasma Ang-(1-12) was higher in the CKD group than in the control (Figure; 0.083±0.006 vs 0.045±0.005 ng/mL, P<0.01). On the other hand, urinary Ang-(1-12) was correlated with neither urinary protein nor eGFR. Urinary Ang-(1-12) tended to be higher in the CKD group than in control (4.94±1.9 vs 1.05±0.6 ng/mL, respectively). The present study showed for the first time that plasma Ang-(1-12) level is elevated in patients with CKD and suggests that increased plasma Ang-(1-12) plays a nephropathic role.

The impact of elevation of serum uric acid level on the natural history of glomerular filtration rate (GFR) and its sex difference

BACKGROUND

The impact of elevation of the serum uric acid level (SUA) on the natural history of glomerular filtration rate (GFR) remains controversial.

METHODS

If elevation of SUA is a result, rather than a cause, of a decline in GFR, the relationship between SUA and GFR should be the same in the same population over years except for shifts by age-dependent reduction of GFR. We tested this hypothesis using data from two cohorts and a group of allopurinol-treated patients.

RESULTS

In Cohort 1 consisting of urban residents aged 40.6 ± 9.0 years (n = 3 446), SUA was inversely correlated with estimated GFR (eGFR) in both men and women, and the slope of the SUA-eGFR relationship was steeper in women than in men. The slopes of the regression lines became significantly steeper after a 6-year interval in both sexes, and the change in the slope was larger in women. A similar sex difference in the SUA-eGFR relationship and 6-year change in the slope were observed in Cohort 2 consisting of rural town residents aged 61.7 ± 12.2 years (n = 404). Multiple regression analyses showed that explanatory factors of eGFR after a 6-year interval were age and SUA at baseline in both cohorts, and partial regression coefficients of SUA were more negative in women than in men. The SUA-eGFR relationship in allopurinol-treated patients (n = 346, 63.5 ± 13.3 years old) was similar to that in Cohort 2.

CONCLUSIONS

The results indicate that elevation of SUA accelerates the yearly decline in eGFR and that women are more susceptible to urate-induced decline in eGFR.

Abstract 604: Renin Independent Ang-(1-12) Production in both the Systemic and Coronary Circulation

Although angiotensin-(1-12) [Ang-(1-12)] is recognized as an alternate precursor for Ang

II, the biochemical pathways by which the substrate is released from

angiotensinogen (Aogen) are not yet described.

We examined the role of renin on Ang-(1-12) formation from synthetic icosapeptide

[Ang-(1-20)] in the systemic and coronary circulation of Wistar Kyoto rats

(WKY). In experiment 1, rats underwent bilateral

nephrectomy (BNX) or sham operation.

After 48 hours, rats were assigned to sham+saline, sham+Ang-(1-20), or

BNX+Ang-(1-20). Ang-(1-20) (20 nmol/kg/min)

or saline was infused for 15 minutes. At

the end of the study blood was collected for measuring Ang-(1-12), Ang I and

Ang II by RIA. Ang-(1-20) infusion increased

arterial pressure in both sham and BNX compared to sham+saline (P<0.001). Plasma Ang-(1-12), Ang I, and Ang II were significantly

higher in sham+Ang-(1-20) compared to sham+saline. BNX+Ang-(1-20) showed significant increase in

Ang I and a tendency for augmented Ang-(1-12) and Ang II compared to sham+saline

(Figure). In experiment 2, the hearts extracted

from WKY were mounted on Langendorff apparatus.

After recovery, 10 nmol or 100 nmol of Ang-(1-20), or 100 nmol of

Ang-(1-20) with WFML-1 (a rat renin inhibitor) were perfused in the coronary

circulation. Buffer was recirculated

after addition of Ang-(1-20) and WFML-1.

Perfusate was collected at 0, 5, 15, 30, and 60 min for measurement of angiotensins

by RIA. The 100 nmol of Ang-(1-20)

increase Ang-(1-12), Ang I, and Ang II compared to 10 nmol both in the absence

and in the presence of WFML-1 (Figure).

We conclude that Ang-(1-12) is cleaved from Aogen by an enzyme that is

not renin in both systemic and coronary circulation.

A case report of the anti-glomerular basement membrane glomerulonephritis with mesangial IgA deposition

A 46-year-old Japanese male with a past medical history of microscopic hematuria presented with nausea, vomiting, and abdominal pain for which he had been diagnosed with rapidly progressive glomerulonephritis with a peak serum creatinine of 6.6 mg/dL and anti-glomerular basement membrane antibody of 214 EU. Light microscopy showed cellular crescent formation, and immunofluorescence illustrated both linear staining of IgG along the glomerular basement membrane and granular staining of IgA and C3 in the mesangial area; however, the PAS staining of mesangial expansions and mesangial proliferations were not observed. Clinical and histological findings suggested anti-glomerular basement membrane glomerulonephritis with mesangial IgA deposition, suggesting IgA nephropathy, a rare condition.