Search

A 60-year-old Japanese woman with polymyositis (PM) developed hemolytic anemia (hemoglobin of 7.3 g/dL), thrombocytopenia (platelet of 9.1×104/µL), and acute kidney injury (Cre of 4.7 mg/dL) at 14 days after starting steroid therapy. Renal biopsy revealed glomerular endothelial swelling with fibrin thrombi and fragmented erythrocytes in the capillary lumens. Hemolytic uremic syndrome (HUS) with thrombotic microangiopathy (TMA) was diagnosed. Hemodialysis and plasma exchange/plasma transfusion were initiated, but HUS did not subside. After 45 days, the patient died of hemorrhagic respiratory failure. Autopsy showed fibrin thrombi filling the glomerular vascular pole and the small arteries in most glomeruli, resulting in glomerular collapse and glomerular basement membrane (GBM) duplication. Although renal involvement by PM is rare, HUS/TMA should be remembered as one of the serious renal complications of PM.

A renal histology of an 81-year-old man with a 30-year history of diabetes mellitus (DM), as well as diabetic retinopathy and neuropathy, was examined. The patient’s blood pressure was controlled within the normal range (less than 140/75 mmHg) using antihypertensive agents including angiotensin receptor blocker. Edematous management was achieved by a strict salt diet (less than 6 g/per day). However, this patient’s glycemic control was poor with HbA1c 8–10%. Serum creatinine was 0.87 mg/dL and estimated globular filtration rate (eGFR) was 64 ml/min/1.73m2. Urinary protein excretion was 1.5 g/day. This patient’s renal biopsy showed linear staining for IgG along the GBM by immunofluorescence microscopy, but light microscopy showed almost intact glomeruli, and the GBM was not thickened as revealed by electron microscopy with a width of 288–368 nm (

BackgroundMethotrexate is widely used to treat rheumatoid arthritis (RA) but can cause very serious side effects, including pancytopenia, in patients with renal impairment who have an estimated glomerular filtration rate (GFR) of 2. In patients with low muscle volume such as elderly patients, GFR can be measured as higher value when calculated using serum creatinine [eGFR(cre)], so more accurate estimation using cystatin C [eGFR(cys)] is preferred.MethodWe evaluated 173 patients with RA who visited Toranomon Hospital in 2019 for factors that may contribute to the difference between eGFR(cre) and eGFR(cys) [eGFR(cre−cys)]. Activities of daily living (ADL) (walking, 1 point; using a cane, 2 points; using a wheelchair, 3 points) was added as a parameter.ResultsIn univariate analysis using Spearman's rank correlation coefficient, eGFR(cre−cys) was negatively correlated with body weight, height, body surface area (BSA), subcutaneous fat area (SFA)/BSA, albumin, and creatinine kinase, and positively correlated with age, erythrocyte sedimentation rate (ESR), and urinary protein. eGFR(cre−cys) was higher in patients who used a cane or wheelchair than those who could walk unaided. Multiple regression analysis showed that ADL and age contribute significantly to eGFR(cre−cys). ConclusionPatients using a cane or wheelchair are susceptible to the higher eGFR(cre−cys) values and overestimation of eGFR(cre), resulting in failed detect subclinical renal dysfunction. For such patients, eGFR(cys) should be evaluated to prevent serious side effects of methotrexate that are easily developed on patients with renal dysfunction.

Background and purpose We examined whether advances in treatment strategies from older disease-modifying antirheumatic drugs (DMARDs) to new biologic agents and methotrexate improved renal complications and outcome in patients with rheumatoid arthritis (RA). Methods We reviewed records of 156 patients with RA who underwent kidney biopsy at our institute between January 1990 and December 2019. All patients were assigned to one of three periods: period 1, 1990–1999 (n = 48); period 2, 2000–2009(n = 57); period 3, 2010–2019 (n = 51). Results Membranous nephropathy, nephrosclerosis, AA-amyloidosis, and IgA nephropathy were the four major renal manifestations of RA. AA-amyloidosis was diagnosed by kidney biopsy in 21 patients: period 1, 7 patients (15%); period 2, 10 patients (18%); and period 3, 4 patients (8%). The 4 patients in period 3 were in the years 2010–2014, and no new case of AA-amyloidosis was recorded from 2015 to 2019. In all 21 of the patients with AA-amyloidosis, neither a biologic agent nor methotrexate was administered. Fifteen of the 21 patients required dialysis, and 13 died in periods 1–3 because of amyloid-related cardiac dysfunction less than 2 years after the initiation of dialysis. Two of them are doing well using biologic agent despite dialysis. The remaining three patients who received a biologic agent or methotrexate does not progress to end-stage renal failure. In addition, the other renal complications showing progression to dialysis also decreased over time. Conclusion Advances in treatment strategies have improved renal outcome and reduced mortality in patients with RA.

Secukinumab is effective to treat plaque psoriasis. However, the safety and efficiency of secukinumab have not been clarified in patients on hemodialysis. We report a 60-year-old Japanese woman. Plaque psoriasis was diagnosed at the age of 25 years and hemodialysis was started at the age of 39 years. Her skin lesions persisted despite use of topical agents such as maxacalcitol and betamethasone. Accordingly, administration of secukinumab was started at a dose of 150 mg. The psoriasis area and severity index (PASI) score decreased from 49.8 to 14.8 after 2 weeks and to 0 after 6 weeks, with remission being maintained after 28 months. No adverse reactions were seen. This case indicates that secukinumab may be effective for severe psoriasis in patients on hemodialysis for end-stage renal disease.

We report a 58-year-old Japanese woman who presented with nephrotic syndrome. Steroid therapy and cyclosporine A administration were initiated, but hematological remission and renal response were not achieved. Renal biopsy revealed amyloid deposits in the mesangial region and the small arteries. Proteomic analysis based on laser microdissection and mass spectrometry showed that the amyloid deposits were composed of the constant region of the lambda light chain. She received vincristine, adriamycin, and dexamethasone therapy followed by high-dose melphalan and autologous stem cell transplantation, resulting in hematological complete remission and renal response with negative urinary Bence-Jones protein and proteinuria. Renal biopsy was performed four times during follow-up, demonstrating that amyloid deposits decreased gradually, while glomeruli showing global sclerosis increased from 3 to 62%. This case suggests that glomerular amyloid deposits can be cleared via tissue remodeling, if stem cells producing amyloid precursors are completely replaced by unrelated cells after stem cell transplantation.

In sarcoidosis, renal involvement includes hypercalcemia-related nephrocalcinosis and granulomatous tubulointerstitial nephritis. Hypercalcemia is thought to be due to increased production of 1,25 dihydroxyvitamin D (1-25D), but 1-25D levels have not been evaluated in sarcoidosis patients with renal dysfunction. We enrolled 9 sarcoidosis patients who underwent renal biopsy, and compared the serum 1-25D concentration and eGFR with those in 428 non-sarcoidosis patients who had renal dysfunction (stage 2 or higher CKD with an estimated glomerular filtration rate

An 88-year-old Japanese man received bevacizumab for colorectal cancer with liver and peritoneal metastasis, during which nephrotic range proteinuria occurred (7.66 g/day). Renal biopsy showed endothelial damage with subendothelial swelling and a double contour of the glomerular basement membrane, which indicated a diagnosis of thrombotic microangiopathy (TMA). After bevacizumab was stopped, proteinuria decreased to 1 g/day. During the clinical course, this patient had no extrarenal manifestations. This case suggests that renal injury induced by bevacizumab is characterized by nephrotic range proteinuria and histological TMA, and is a renal-limited condition that differs from systemic TMA related to thrombotic thrombocytopenic purpura.

Cholesterol crystal embolism (CCE) causes renal damage, and there is an extremely high risk of end-stage renal disease. However, the time course of CCE-related renal deterioration varies and little is known about the subsequent risk of dialysis among patients with biopsy-proven CCE. We performed a retrospective cohort study of 38 Japanese patients in whom a histological diagnosis of CCE was made from September 1992 to July 2005. Competing risk regression analysis was used to investigate the association between declining renal function ( ≥ 1.5 elevation of serum creatinine within 26 weeks after CCE) or its subtypes (acute [

Background This study was performed to determine whether the urinary albumin excretion rate (%UAE) could distinguish myeloma cast nephropathy (MCN) without glomerular amyloid deposition from MCN with glomerular amyloid deposition. Materials and methods We retrospectively reviewed clinicopathological data on 16 patients with MCN diagnosed by renal biopsy at Toranomon Hospital from 2004 to 2014. Results A total of 10 patients had pure MCN without glomerular amyloid deposition (group 1), and 6 patients had MCN with glomerular amyloid deposition (group 2). In all 10 patients from group 1, the underlying disease was multiple myeloma (MM), while 4 patients had MM, and 2 patients had lymphoplasmacytic lymphoma/Waldenstrom macroglobulinemia (LPL/WM) in group 2. Total protein did not show a significant difference between the two groups, but serum albumin was significantly higher in group 1 than group 2 (p = 0.0101). Serum-adjusted calcium did not show a significant difference between the groups, while serum creatinine (Cre) was significantly higher in group 1 than group 2 (p = 0.0343). Although urinary protein excretion did not differ significantly between the groups, the %UAE was significantly lower in group 1 than group 2 (p = 0.00198). In group 2, 3 of the 4 patients with MM died within 15 months of diagnosis, but the 2 patients with LPL/WM are alive after 32 months. In group 1, only 1 patient died (of unknown causes) within 15 months after diagnosis. Conclusion In patients with MCN, %UAE may be a useful marker for the detection of coexistence of glomerular lesions, such as amyloidosis, which are associated with a poor outcome.

A 32-year-old Japanese woman was admitted to our hospital for evaluation of microscopic hematuria with a positive family history. Percutaneous renal biopsy was performed under real-time ultrasound guidance using a 16-gauge automated needle and three specimens were obtained. She had no risk factors for hemorrhage. However, macroscopic hematuria developed from 5 days after biopsy and persisted for 4 days. Her Hb decreased markedly from 15.0 to 8.1 g/dL. Enhanced computed tomography revealed urinary tract hematoma, while the early arterial phase showed inflow of contrast medium into the left renal vein from a pseudoaneurysm on a branch left renal artery. Renal transcatheter arterial embolization was performed using platinum microcoils and the arteriovenous fistula was occluded. The patient did not require blood transfusion. Severe renal bleeding that causes urinary tract hematoma usually occurs within 24 h after renal biopsy, but the possibility of late-onset renal bleeding should be kept in mind.

A 74-year-old Japanese woman diagnosed with autosomal dominant polycystic kidney disease (ADPKD) was admitted to our institute for the further examination of right-side groin pain developing in the past week. The patient was diagnosed with polymyositis (PM). Diagnostic imaging showed a mass lesion measuring 8 cm and a renal stone in the right kidney. Immediately following surgical resection of the right kidney, the patient's serum CK decreased to the normal range. A histopathological analysis showed well-differentiated squamous cell carcinoma. In conclusion, this case showed a close relationship between the occurrence of squamous cell carcinoma and the development of PM in an ADPKD patient.

Background Increases in bone mineral density (BMD) following a single dose of denosumab and increased incidence of denosumab-associated acute hypocalcemia (DAAH) have been reported in chronic kidney disease patients. Little is known about clinical risk factors related to DAAH and the long-term effect of denosumab on BMD in hemodialysis patients. Methods An observational noncontrolled study involving 47 hemodialysis patients was conducted to determine the independent risk factors related to percentage changes in serum calcium (Ca) levels associated with denosumab using multivariate regression analysis. Optimal predictive markers for DAAH were explored by receiver operating characteristic analysis. Percentage changes of BMD at the lumbar spine (LS) and femoral neck (FN) at 24 months were investigated. Results The incidence of DAAH [serum corrected Ca (cCa) ≤8 mg/dL] following denosumab was 25.5%. Multivariate regression analysis showed that baseline bone alkaline phosphatase was independently related to percentage changes in cCa levels (β = −0.407, P = 0.008). Tartrate-resistant acid phosphatase-5b was found to be the most accurate marker to predict DAAH, with an area under the curve of 0.750 (95% confidence interval 0.546–0.954; P = 0.02), and the optimal cut-off level was 670 mU/mL with sensitivity: 0.727 and specificity: 0.733. BMD significantly increased by 5.9 ± 1.7% (P = 0.01) at LS and 4.2 ± 1.5% (P = 0.04) at FN at 24 months. Conclusions In hemodialysis patients, high bone turnover was an independent risk factor for the Ca declines induced by denosumab. Denosumab significantly increased BMD at LS and FN at 24 months.

Background and Aims Daily 20µg teriparatide (PTH1-34) is an osteoanabolic agent approved for use treating osteoporosis. However, there are few reports about concerning use of this agent in hemodialysis patients. Method We conducted an observational study, single centre study on 5 patients with low bone mineral density (BMD) and low iPTH levels defied as iPTH below 60 pg/mL, who were treated with recombinant human PTH1-34; teriparatide 20 µg 3 times per week between January 2012 and January 2015. All patients were 20 years of age or older, had undergone regular hemodialysis treatment and were without skeletal malignancies and bone metastasis. Low BMD in this study was defined either as BMD T-score -2.5 at the lumbar spine (LS) or /and femoral neck (FN) and distal one –third radius (RS) analyzed by dual-energy X-ray absorptiometry (DXA), or BMD T-score of -2.5 to -1.0 with history of fragility fractures. We analyzed the biochemical data including bone metabolic makers (intact amino-terminal propeptide of type I collagen (iP1NP), bone alkaline phosphatase (BAP), and tartrate-resistant acid phosphatase-5b (TRACP-5b) at baseline, and after 3, 6, and 12 months of teriparatide treatment. BMD at LS and FN were evaluated at 6months of treatment. Results Data from five patients (mean age: 69.2±7.4years; mean hemodialysis time: 23.2±6.2years) were reviewed. Laboratory data at baseline were iPTH: 34.2±24.2 pg/mL, BAP: 13.0±4.9 µg/L, iP1NP: 45.3±14.3 ng/mL, TRACP-5b: 350±201 mU/dL, corrected Ca (cCa): 9.7±0.3 mg/dL, and P:4.1±0.7 mg/dL. Baseline BMD T-score at LS and FN were -2.8±1.7 and -3.0±0.6, respectively. During a 12 month- teriparatide treatment, mean cCa levels significantly decreased from 9.7±0.3 to 9.1±0.2 mg/dL at 3 months (P < 0.05) and returned to 9.5±0.4 mg/dL at 12 months. As for bone metabolic markers, BAP and iP1NP significantly increased from baseline by 31.3±12.9 (P < 0.05) and 47.4±14.5% (P < 0.05) at 6 months of teriparatide treatment, while TRACP-5b significantly decreased by 10.5±2.5% at 3 months, which did not reach a statistical significance. BMD changes from baseline at LS and FN were 2.1±2.5% and 1.2±1.5% at 6 months of treatment with a significant change at LS. Pharmacokinetics of Teriparatide The time-course of changes in plasma teriparatide acetate concentration was evaluated in one patient who had undergone parathyroidectomy 20 years before enrollment in this study and her serum endogenous iPTH level was undetectable at baseline. After teriparatide injection, serum teriparatide acetate levels peaked at 30 minutes at 157.2 pg/mL, and then rapidly decreased to undetectable levels at 240 minutes. Conclusion We report that teriparatide improved LS and FN BMD in hemodialysis patients with low iPTH. Pharmacokinetics showed this agent might not accumulate in dialysis patients and can be used safely. Adequate Ca supplementation might be needed to adjust serum Ca levels.

Background: Tolvaptan is the only therapeutic drug for autosomal dominant polycystic kidney disease (ADPKD). The influence of mutations in polycystic kidney disease 1 and 2 genes (PKD1 and PKD2) on the treatment effects of tolvaptan is not well documented in the literature. Methods: We retrospectively evaluated the relationship between genotype and the efficacy of tolvaptan in 18 patients with ADPKD who had been treated at Toranomon Hospital and undergone genetic testing between April 2016 and February 2020. Results: The annual change in estimated glomerular filtration rate (ΔeGFR/y) from before to after tolvaptan was from a median of −5.5 to −2.5 mL/min/1.73 m2 in the PKD1 truncating group, −3.3 to −2.4 mL/min/1.73 m2 in the PKD1 non-truncating group, −3.1 to −1.6 mL/min/1.73 m2 in the PKD2 group, and −1.9 to −2.6 mL/min/1.73 m2 in the group with no PKD1/2 mutation. The median degrees of improvement of ΔeGFR/y were 2.5 (45%), 0.4 (10%), 0.6 (28%), and −0.7 (−37%) mL/min/1.73 m2, respectively. Compared with the group of patients with any PKD1/2 mutation, the group with no PKD1/2 mutation showed significantly less improvement in ΔeGFR/y with tolvaptan (0.6 vs. −0.7 mL/min/1.73 m2, respectively; p = 0.01) and significantly less improvement in the annual rate of increase in total kidney volume (TKV) with tolvaptan (−6.7 vs. −1.1%, respectively; p = 0.02). Conclusion: Patients with ADPKD and no PKD1/2 mutation showed less improvement in ΔeGFR/y and the annual rate of increase in TKV with tolvaptan. Detecting PKD1/2 mutations may be useful for predicting the effectiveness of tolvaptan.

ObjectivesTo investigate the association between chronic kidney disease (CKD) and dementia diagnosis in a real-world primary care setting in England.DesignMatched cohort study.SettingsEnglish primary care in the Clinical Practice Research Datalink.ParticipantsPeople aged ≥18 years with predialysis CKD (stages 3–5, defined as two measurements of estimated glomerular filtration rate 2 for 3 months) from 2004 to 2014, and people without known CKD who were matched on age, sex, general practice and calendar time in a 1:1 ratio.Primary and secondary outcome measuresFirst-ever diagnosis of dementia recorded by GPs. We also examined all-cause death as a secondary outcome to discuss potential competing risk of mortality in the association between CKD and dementia diagnosis.ResultsIn a matched cohort of 242 349 pairs with and without CKD (mean age 75.4±9.7 years, 39.3% male), the crude incidence rate of dementia diagnosis was 11.4/1000 and 9.4/1000 person-years, respectively. There was an association between CKD status and incident dementia diagnosis in the first 6 months of the follow-up (adjusted rate ratio (aRR) 1.58, 95% CI 1.44 to 1.74), which attenuated after 6 months (aRR 1.12, 95% CI 1.08 to 1.16). Among patients with CKD, there was no evidence of association between CKD stage and incident dementia diagnosis; compared with stage 3a, aRR (95% CI) was 1.04 (0.91 to 1.18) for stage 3b and 0.94 (0.74 to 1.20) for stages 4 or 5 in the first 6 months, and 0.97 (0.92 to 1.01) and 0.89 (0.80 to 0.98) thereafter. We found a strong association between worsening CKD stage and all-cause mortality.ConclusionWe identified a co-occurrence of detection of CKD and dementia in real-world clinical practice and a strong competing risk of mortality in the association between CKD stage and dementia, while a weak association between CKD status and dementia was suggested in the long term.

Objectives In lupus nephritis, the immune complex plays a very important role in kidney disease progression, and immunoglobulin G subclass 3 (IgG3) may play an important role in endothelial damage as lupus nephropathy progresses. We evaluated the association between IgG3 positivity and lupus nephritis activity. Materials and methods We identified 71 biopsies taken from 57 patients who had lupus nephritis with enough tissue to allow light and immunofluorescence microscopy. We compared the intensity of IgG subclass staining (on a scale of 0 - 3+) with IgG subclass dominance among lupus nephritis classes as defined by the ISN/RPS 2003 classification. Results The proportion of IgG3-positive patients with capillary loop lesion was significantly higher in the class IV group compared with other groups (p l 0.01). Interestingly, in most patients IgG1 was the strongest subclass; in class IV groups, IgG3 was the strongest in 21% of the biopsies. IgG3 deposition in capillary loops was significantly associated with C1q deposition in those loops. According to Kaplan-Meier analysis, renal survival rates in the patients with IgG3 deposition was lower (82.2%) than in patients without IgG3 deposition (93.3%), but the difference was not significant. Conclusion Our results suggest that capillary loop deposition of IgG3 is associated with disease activity in lupus nephritis. .

Background: Genetic characteristics of polycystic kidney disease (PKD) patients without apparent family history were reported to be different from those with a positive family history. However, the clinical course of PKD patients with no apparent family history is not well documented in the literature. Methods: We evaluated the relationship between genotype and the clinical course of 62 PKD patients with no apparent family history. Results: The annual decline of renal function was faster in the patients with PKD1/PKD2 mutation (PKD1 truncating [–3.08; 95% CI –5.30 to –0.87, p = 0.007], PKD1 nontruncating [–2.10; –3.82 to –0.38, p = 0.02], and PKD2 [–2.31; –4.40 to –0.23, p = 0.03]) than in the other patients without PKD1/PKD2 mutation. Similar results were obtained after adjustment for gender, age, estimated glomerular filtration rate (eGFR), height-adjusted total kidney volume (TKV), and mean arterial pressure (MAP). There was no significant difference in the annual decline of renal function among the different PKD1/PKD2 groups, but Kaplan-Meier analysis showed that progression to eGFR < 15 mL/min/1.73 m2 was significantly faster in PKD1 truncating group (p = 0.05). The annual rate of TKV increase was larger in the patients with PKD1/PKD2 mutation (PKD1 truncating [4.63; 95% CI 0.62–8.64, p = 0.03], PKD1 nontruncating [3.79; 0.55–7.03, p = 0.02], and PKD2 [2.11; –1.90 to 6.12, p = 0.29]) than in the other patients without PKD1/PKD2 mutation. Similar results were obtained after adjustment for gender, age, eGFR, and MAP. Conclusion: Detection of PKD1/PKD2 mutation, especially PKD1 truncating, is useful for predicting the renal outcome and rate of TKV increase in PKD patients with no apparent family history.

Background: Cyst infection is a frequent and serious complication of autosomal dominant polycystic kidney disease (ADPKD) that is often difficult to treat. However, the factors influencing cyst infection are still unknown. Therefore, we investigated clinical factors related to the duration of hospitalization and death due to cyst infection. Methods: All ADPKD patients undergoing cyst drainage or nephrectomy or partial hepatectomy at Toranomon Hospital from January 2004 to March 2016, in whom cyst fluid analysis showed bacteria or neutrophils indicating definite cyst infection, were reviewed retrospectively. Factors influencing the duration of hospitalization and death due to cyst infection were analyzed. Results: A total of 243 patients with cyst infection were enrolled, including 104 men and 139 women (mean age: 62.6 ± 10.0 years). Seventeen patients died of cyst infection. Multivariate logistic regression analysis revealed that hepatomegaly, positive cyst contents culture, and the maximum white blood cell (WBC) count were significantly associated with death from cyst infection. Death was significantly more likely if patients had massive hepatomegaly (≥5,113.2 mL) compared with mild hepatomegaly (< 1,898.7 mL; odds ratio 38.1; 95% CI 2.9–492.6, p = 0.0004). Multivariate Cox proportional hazards analysis revealed that older age, dialysis duration, hepatic transcatheter arterial embolization, maximum WBC count, and hepatomegaly were significantly associated with longer hospital stay for cyst infection, while female sex, nephrectomy, serum albumin, and serum cholinesterase were significantly associated with shorter hospital stay. Discharge alive from hospital was significantly associated with massive hepatomegaly versus mild hepatomegaly (hazard ratio 0.0072; 95% CI 0.0008–0.0659, p < 0.0001). Conclusions: Hepatomegaly was strongly associated with both death and longer hospital stay due to cyst infection.

A recent study demonstrated that tolvaptan slowed estimated glomerular filtration rate (eGFR) decline in later-stage autosomal dominant polycystic kidney disease (ADPKD) patients. However, Japanese patients were not included in that trial, therefore tolvaptan’s efficacy in Japanese patients with advanced chronic kidney disease (CKD) has remained unknown. In this prospective cohort study, 54 patients with ADPKD who had eGFR ≥ 15 ml/min/1.73 m2 and total kidney volume (TKV) ≥ 750 ml were treated with tolvaptan. The primary endpoint was the change in height-adjusted total kidney volume (htTKV) and eGFR after 1-year treatment with tolvaptan. Then, we compared the primary endpoint between later CKD stage (baseline eGFR

Diabetic kidney disease (DKD) is the major cause of end stage renal disease. Despite the best current treatment, it is difficult to stop the progression of DKD. We report a 77-year-old Japa...

A 72-year-old Japanese woman with a history of autoimmune hepatitis-associated liver cirrhosis and portosystemic shunt was admitted to our hospital for evaluation of renal dysfunction, nephrotic range proteinuria, a high titer of anti-double-stranded DNA antibody, and hypocomplementemia. Renal biopsy showed massive subendothelial deposits (wire loop lesions), and class IV-G (A/C) lupus nephritis was diagnosed. Immunosuppressants, such as steroids (including intravenous methylprednisolone pulse therapy) and mycophenolate mofetil, could not prevent renal dysfunction. It was assumed that circulating immune deposits produced in the gastrointestinal tract entered the systemic circulation from the portal vein via the portosystemic shunt without hepatic clearance, resulting in massive subendothelial and mesangial accumulation compared to lupus nephritis patients without a shunt and causing renal injury. Keywords: Lupus nephritis, Systemic lupus erythematosus, Autoimmune hepatitis-associated liver cirrhosis, Portosystemic shunt, Wire loop lesion

A 42-year-old woman with systemic lupus erythematosus (SLE) was admitted to our hospital for evaluation of severe thrombocytopenia. She was treated with steroids, intravenous cyclophosphamide, intravenous immunoglobulin, and plasma exchange, but her thrombocytopenia did not improve. Renal biopsy showed class IV-S(C) + V lupus nephritis, according to the classification of the International Society of Nephrology/Renal Pathology Society. The PA-IgG and serum thrombopoietin (TPO) levels were elevated. Her thrombocytopenia responded to off-label administration of eltrombopag, which was discontinued after 42 months. At 18 months after stopping eltrombopag, the platelet count was 19.3 × 104/μL. Eltrombopag may be a therapeutic option for SLE patients with severe thrombocytopenia refractory to conventional therapy.

Cryoglobulinemic vasculitis (CV) presents with systemic manifestations, including renal disease, arthritis, peripheral neuropathy, and muscle weakness. We encountered two patients who developed severe nephrotic range proteinuria; however, extrarenal manifestations were not noted during the clinical course. A renal biopsy revealed typical membranoproliferative glomerulonephritis (MPGN) with huge thrombus-like endothelial deposits and predominant IgM positivity, but electron microscopy did not reveal any definite microtubules. Immunosuppressive therapy and plasmapheresis were only partially effective, and the improvement was not durable. Biological therapy with rituximab (RTX) had no effect. Renal-limited CV should be recognized as a subset of essential CV.

We report a 38-year-old Japanese man in whom lupus membranous nephropathy was diagnosed by renal biopsy. Steroid therapy was initiated, followed by cyclophosphamide and calcineurin inhibitors. Alth...

We encountered 2 patients with symptomatic huge simple renal cysts. In case 1, 4,000 mL of cyst fluid was drained via a catheter, but intracystic bleeding occurred immediately afterwards. Transcatheter arterial embolization (TAE) was performed, after which the bleeding stopped, and cyst drainage was repeated successfully. After 2 years, the total cyst volume was reduced from 11,775 mL to 75.4 mL. In case 2, TAE was performed prophylactically before drainage. Subsequently, 9,400 mL of fluid was removed from multiple cysts. After 1 year, the total cyst volume was reduced from 9,215 mL to 633 mL without bleeding. Based on these 2 cases, prophylactic TAE before drainage may be useful in patients with huge renal cysts.

We report a 33-year-old Japanese man diagnosed with mixed connective tissue disease (MCTD) who developed nephrotic proteinuria. Both speckled antinuclear antibody (ANA) and anti-U1 ribonucleoprotein (RNP) antibody were positive, but anti-double-stranded DNA (dsDNA) antibody and anti-Smith (Sm) antibody were negative, while complement levels were normal. Renal biopsy revealed membranous glomerulonephritis (MGN) with diffuse thickening of the glomerular basement membrane (GBM) plus spike and bubble formation. Immunofluorescence demonstrated granular deposits of IgG and C3 along the GBM. Analysis of IgG subclasses showed predominant deposition of IgG1 and IgG4, unlike typical lupus nephritis in which there is predominant deposition of IgG1, IgG2, IgG3, and C1q. Electron microscopy identified numerous large electron-dense deposits (EDD) of various types in the subepithelial region of the GBM, but there were no EDD localized in the mesangium or subendothelium. Based on these findings, MGN was considered to be closely related to MCTD in this patient. Keywords: Membranous glomerulonephritis, Mixed connective tissue disease

A 59-year-old Japanese woman was admitted for evaluation of muscle weakness. Autosomal dominant polycystic kidney disease had been diagnosed at the age of 47 years, followed by primary aldosteronism at 53 years. At the age of 58, tolvaptan was started (60 mg/day) to treat her renal disease. After 8 months of tolvaptan therapy, hypokalemia-related muscle weakness became prominent, and hypertension became refractory. Finally, treatment with low-dose tolvaptan (30 mg/day) and high-dose spironolactone (100 mg/day) normalized serum potassium and the blood pressure. Tolvaptan can induce urinary excretion of potassium in patients with primary aldosteronism, and possible mechanisms are discussed.

A 55-year-old man was admitted to our institute to undergo evaluation for proteinuria (5.4 g/day) with lambda-type Bence-Jones protein (BJP). Primary amyloid light chain (AL) amyloidosis and acquired factor X deficiency were diagnosed. High-dose melphalan combined with autologous stem cell transplantation was performed. After three years, the patient's proteinuria normalized, he was negative for urinary BJP, and his factor X activity improved to 105%. Serial renal biopsy showed no progression of amyloid deposition at a biopsy after 5 years, but showed a slight increase in the amyloid deposition after 11 years. This therapy can improve the prognosis of AL amyloidosis; however, there are limitations to the strategy.

A 44-year-old Japanese woman with autosomal dominant polycystic kidney disease was admitted to our hospital for evaluation of abdominal distension. Her eGFR was 53.7 mL/min/1.73 m2. Total kidney volume was 2,614 mL. Tolvaptan (60 mg/day) was started to treat renal involvement. The patient’s abdominal fullness began to improve and liver volume, indicating advanced polycystic liver disease (PLD), decreased from 9,750 mL to 8,345 mL after 17 months of tolvaptan treatment, though there was no significant change in kidney volume. This case indicates that tolvaptan may be a therapeutic option for hepatomegaly in patients with symptomatic PLD.

A 54-year-old Japanese man presented with recurrent abdominal pain, fever lasting >5 days, and renal failure. AA amyloidosis was proven by renal and gastric biopsy. Symptoms subsided with the administration of colchicine, but a subsequent recurrence of symptoms did not respond to colchicine. Mediterranean fever gene (MEFV) analysis showed that he was heterozygous for mutations in exon 2 (E148Q/R202Q) and exon 3 (P369S/R408Q), although he had none of the exon 10 mutations known to be closely related to AA amyloidosis. He did not respond to infliximab, but tocilizumab therapy was successful. The present case is a rare report of AA amyloidosis associated with familial Mediterranean fever in Japan.

A 41-year-old man was referred to our hospital for the evaluation of hypergammaglobulinemia (IgG 2898 mg/dL and IgA 587 mg/dL), inflammation (CRP 6.7 mg/dL and serum interleukin-6 (IL-6) 15.1 ng/L), and anemia (Hb 10.9 mg/dL). Castleman's disease (CD) was diagnosed by axillary lymph node biopsy. Five months later, painful purpura (multiple palpable 5 mm lesions) developed on his legs, gradually spreading to the upper limbs, thighs, and trunk, accompanied by arthralgia of the wrists, ankles, and knees. Skin biopsy revealed leukocytoclastic vasculitis with IgA deposits in dermal vessels. Accordingly, IgA vasculitis (Henoch-Schönlein purpura) was diagnosed. Tocilizumab (an anti-IL-6 receptor antibody) was administered intravenously at 8 mg/kg and treatment was repeated at monthly intervals. His purpura and clinical findings specific to CD improved rapidly. CD is well known to cause various skin lesions. The findings in this case indicate that overproduction of IL-6 contributes to IgA vasculitis (Henoch-Schönlein purpura) as well as to the pathogenesis of CD.