Membranous nephropathy associated with multicentric Castleman's disease that was successfully treated with tocilizumab: a case report and review of the literature.

BACKGROUND: Multicentric Castleman's disease is a life-threatening disorder involving a systemic inflammatory response and multiple organ failure caused by the overproduction of interleukin-6. Although renal complications of Castleman's disease include AA amyloidosis, thrombotic microangiopathy, and membranoproliferative glomerulonephritis, membranous nephropathy is relatively rare. We experienced a case of secondary membranous nephropathy associated with Castleman's disease. CASE PRESENTATION: The patient was a 43-year-old Japanese man who had shown a high zinc sulfate value in turbidity test, polyclonal hypergammaglobulinemia, anemia, and proteinuria. A physical examination revealed diffuse lymphadenopathy, an enlarged spleen and papulae of the body trunk. A skin biopsy of a papule on the patient's back showed plasma cells in the perivascular area and he was diagnosed with multicentric Castleman's disease, plasma cell variant. Kidney biopsy showed the appearance of bubbling in the glomerular basement membranes in Periodic acid methenamine silver stain and electron microscopy revealed electron dense deposits within and outside the glomerular basement membranes. Since immunofluorescence study showed predominant granular deposition of IgG1 and IgG2, he was diagnosed with secondary membranous nephropathy associated with Castleman's disease. He was initially treated with prednisolone alone, however his biochemical abnormalities did not improve. After intravenous tocilizumab (700 mg every 2 weeks) was started, his C-reactive protein elevation, anemia, and polyclonal gammopathy improved. Furthermore, his urinary protein level declined from 1.58 g/gCr to 0.13 g/gCr. The prednisolone dose was gradually tapered, then discontinued. He has been stable without a recurrence of proteinuria for more than 6 months. CONCLUSIONS: Tocilizumab might be a treatment option for secondary membranous nephropathy associated with Castleman's disease.

Correction to: Clinical characteristics and genetic backgrounds of Japanese patients with atypical hemolytic uremic syndrome.

The original article can be found online.

The effect of an L/N-type calcium channel blocker on intradialytic blood pressure in intradialytic hypertensive patients.

BACKGROUND: Intradialytic hypertension (HTN), which is one of the poor prognostic markers in patients undergoing hemodialysis, may be associated with sympathetic overactivity. The L/N-type calcium channel blocker, cilnidipine, has been reported to suppress sympathetic nerves activity in vivo. Therefore, we hypothesized that cilnidipine could attenuate intradialytic systolic blood pressure (SBP) elevation. METHODS: Fifty-one patients on chronic hemodialysis who had intradialytic-HTN (SBP elevation ≥10 mmHg during hemodialysis) and no fluid overload were prospectively randomized into two groups: control and cilnidipine groups. Cilnidipine group patients took cilnidipine (10 mg/day) for 12 weeks. The primary endpoint was the change in the intradialytic SBP elevation before and after the 12-week intervention. RESULTS: Before the intervention, no differences were observed in age, sex or pre-dialytic SBP (148.5 ± 12.9 vs. 148.3 ± 19.3 mmHg) between the two groups. Intradialytic SBP elevation was unchanged in the control group. Cilnidipine significantly lowered the post-dialytic SBP with an attenuation of the intradialytic SBP elevation from 12.0 ± 15.4 mmHg to 4.8 ± 10.1 mmHg. However, the observed difference in the intradialytic SBP elevation by cilnidipine did not reach statistical significance (group×time interaction effect p = 0.25). Cathecolamine levels were unaffected by the intervention in both groups. CONCLUSION: Cilnidipine lowers both the pre- and post-dialytic SBP and might attenuate intradialytic SBP elevation. Therefore, cilnidipine may be effective in lowering SBP during HD in patients with intradialytic-HTN.

Clinical characteristics and genetic backgrounds of Japanese patients with atypical hemolytic uremic syndrome.

BACKGROUND: Atypical hemolytic uremic syndrome (aHUS) is caused by complement overactivation, and its presentation and prognosis differ according to the underlying molecular defects. The aim of this study was to characterize the genetic backgrounds of aHUS patients in Japan and to elucidate the associations between their genetic backgrounds, clinical findings, and outcomes. METHODS: We conducted a nationwide epidemiological survey of clinically diagnosed aHUS patients and examined 118 patients enrolled from 1998 to 2016 in Japan. We screened variants of seven genes related to complement and coagulation, as well as positivity for anti-CFH antibodies, and assessed clinical manifestations, laboratory findings, and clinical course. RESULTS: The most frequent genetic abnormalities were in C3 (31%) and the frequency of CFH variants was relatively low (10%) compared to Western countries. The predominant variant in this cohort was C3 p.I1157T (23%), which was related to favorable outcomes despite frequent relapses. A total of 72% of patients received plasma therapy, while 42% were treated with eculizumab. The prognosis of Japanese aHUS patients was relatively favorable, with a total mortality rate of 5.4% and a renal mortality rate of 15%. CONCLUSIONS: The common occurrence of genotype C3, especially the p.I1157T variant was the characteristic of the genetic backgrounds of Japanese aHUS patients that differed from those of Caucasian patients. In addition, the favorable prognosis of patients with the unique C3 p.I1157T variant indicates that understanding the clinical characteristics of individual gene alterations is important for predicting prognosis and determining therapeutic strategies in aHUS.

Spontaneous remission of adult-onset minimal change nephrotic syndrome associated with influenza B infection: a case report.

BACKGROUND: While the majority of adult-onset minimal change nephrotic syndrome (MCNS) is a primary or an idiopathic form of disease, it can also occur as a secondary form. Reports on the spontaneous remission of MCNS are rare since the condition is typically treated with corticosteroids. We herein describe the spontaneous remission of adult-onset MCNS in a patient who developed nephrotic syndrome after type B influenza infection. CASE PRESENTATION: A 50-year-old woman experienced fever, cough, malaise, and low back pain, which had persisted for 6 days before she presented to our hospital, and edema of the face and limbs, which had persisted for 5 days before her presentation. She was diagnosed with type B influenza infection and later exhibited an exacerbation of facial edema, decreased urine output, and a high level of proteinuria. She was referred to our department after the diagnosis of nephrotic syndrome. On admission, her proteinuria level was 20.88 g/gCr and her selectivity index value was 0.13. The examination of a kidney biopsy specimen obtained on the fourth day of hospitalization under a light microscope revealed minor abnormalities. An immunofluorescence showed only nonspecific granular IgM deposits in the mesangium. Electron microscopy showed extensive foot process effacement without any immune complex deposits. Based on these findings, the patient was diagnosed with MCNS. After admission, the proteinuria decreased to 0.06 g/gCr with rest and sodium restriction (6 g/day) alone; a complete remission from nephrotic syndrome was observed at approximately 2 weeks after the onset of symptoms. There have been no signs of recurrence of nephrotic syndrome in the one years since. CONCLUSION: We experienced a rare case in which spontaneous remission of MCNS occurred within a short period of 2 weeks after influenza B infection. When patients present with nephrotic syndrome after an infection, it is necessary to consider MCNS in the differential diagnosis, which also includes post-infectious glomerulonephritis and the acute exacerbation of IgA nephropathy.

Granulomatous interstitial nephritis due to chronic lymphocytic leukemia: a case report.

BACKGROUND: Renal failure due to the infiltration of chronic lymphocytic leukemia (CLL) cells into the tubulointerstitial area of the kidney is uncommon. Furthermore, granulomatous interstitial nephritis (GIN) is a rare histological diagnosis in patients undergoing a renal biopsy. We herein report a case of GIN due to the diffuse infiltration of CLL cells in a patient who developed progressive renal failure. CASE PRESENTATION: The patient was a 55-year-old man who had been diagnosed with CLL 4 years earlier and who had been followed up without treatment. Although his serum creatinine level had remained normal for three and a half years, it started to increase in the six months prior to his presentation. A urinalysis showed mild proteinuria without any hematuria at the time of presentation. A renal biopsy revealed the diffuse infiltration of CLL cells into the tubulointerstitial area with non-caseating epithelioid cell granulomas. Despite cyclophosphamide treatment, his renal function did not improve, and he ultimately required maintenance hemodialysis. CONCLUSION: When progressive renal failure is combined with CLL, GIN due to the direct infiltration of CLL cells should be considered as a differential diagnosis.

The relationship between sarcopenic obesity and changes in quadriceps muscle thickness and echo intensity in patients with stroke.

BACKGROUND: Research findings on skeletal muscle degeneration in post-stroke sarcopenic obesity are limited. Thus, this study aimed to investigate the association between post-stroke sarcopenic obesity and quantitative and qualitative changes in skeletal muscles. METHODS: This was a cross-sectional study conducted on patients with stroke admitted to the convalescent rehabilitation ward. For skeletal muscle assessment, an ultrasound system was used to measure quadriceps muscle thickness and echo intensity (QMT and QEI) on the paretic and non-paretic sides. Sarcopenic obesity was defined as the presence of both sarcopenia and obesity. Multiple regression analysis was performed to determine the relationships between sarcopenic obesity and QMT and QEI. RESULTS: A total of 130 patients with stroke were included in this study (mean age: 69.4 ± 12.7 years). The prevalence of sarcopenic obesity was 23.1%. The multiple regression analysis showed that sarcopenic obesity was significantly negatively associated with QMT on both the paretic and non-paretic sides (paretic side: ß = -0.28, p < 0.001; non-paretic side: ß = -0.37, p < 0.001) and significantly positively associated with QEI (paretic side ß = 0.21, p = 0.034; non-paretic side: ß = 0.20, p = 0.029). CONCLUSIONS: Post-stroke sarcopenic obesity was independently associated with quantitative and qualitative changes in skeletal muscles on both the paretic and non-paretic sides.

The Validity of Quadriceps Muscle Thickness as a Nutritional Risk Indicator in Patients with Stroke.

This study aimed to investigate whether quadriceps muscle thickness (QMT) is useful for nutritional assessment in patients with stroke. This was a retrospective cohort study. Nutritional risk was assessed using the Geriatric Nutritional Risk Index (GNRI), with GNRI < 92 indicating a risk of malnutrition and GNRI ≥ 92 indicating normal conditions. Muscle mass was assessed using QMT and calf circumference (CC). The outcome was Functional Independence Measure (FIM) effectiveness. The cutoff values of QMT and CC for discriminating between high and low GNRI were determined using the receiver operating characteristic curve. The accuracy of the nutritional risk discrimination model was evaluated using the Matthews correlation coefficient (MCC). Multiple regression analysis was performed to assess the relationship between nutritional risk, as defined by QMT and CC, and FIM effectiveness. A total of 113 patients were included in the analysis. The cutoff values of QMT and CC for determining nutritional risk were 49.630 mm and 32.0 cm for men (MCC: 0.576; 0.553) and 41.185 mm and 31.0 cm for women (MCC: 0.611; 0.530). Multiple regression analysis showed that only nutritional risk defined by QMT was associated with FIM effectiveness. These findings indicate that QMT is valid for assessing nutritional risk in patients with stroke.

Renal Medullary Angiitis Associated with Cutaneous Leukocytoclastic Vasculitis: A Case Report.

Renal medullary angiitis is characterized by interstitial hemorrhaging in the medulla with neutrophil infiltration. An 81-year-old man presented with a fever, kidney dysfunction, and purpura of the legs, which was diagnosed as leukocytoclastic vasculitis. Proteinase 3 antineutrophil cytoplasmic antibodies were weakly positive. A kidney biopsy showed severe tubulointerstitial hemorrhaging with neutrophilic infiltration in the perivascular areas surrounding the vasa recta in the medulla without crescent formation in the glomeruli. An immunofluorescence analysis was negative, and electron microscopy revealed no immune-dense deposits, ruling out immunoglobulin A vasculitis. Intravenous methylprednisolone for three days and plasma exchange followed by oral prednisolone improved his general condition.

Bullous Pemphigoid in X-linked Alport Syndrome.

Skin lesions in X-linked Alport syndrome (XLAS) are rarely observed. Bullous pemphigoid (BP) is caused by autoantibodies against BP180, also called α1 (XVII) chain, in the basement membrane zone (BMZ). A 48-year-old man with XLAS developed tense blisters. A skin biopsy showed a cleft between the basal cell layer and dermis, with the infiltration of neutrophils and eosinophils. α1 (XVII) staining was positive on the epidermal side of α2/5 (IV) staining. Oral prednisolone improved his symptoms gradually. Abundant tense blisters on the palms and soles might suggest an important role of the α5 (IV) chain in the integrity of BMZ.

Mutation Analysis of Thin Basement Membrane Nephropathy.

Thin basement membrane nephropathy (TBMN) is characterized by the observation of microhematuria and a thin glomerular basement membrane on kidney biopsy specimens. Its main cause is heterozygous mutations of COL4A3 or COL4A4, which also cause late-onset focal segmental glomerulosclerosis (FSGS) or autosomal dominant Alport syndrome (ADAS). Thirteen TBMN cases were analyzed using Sanger sequencing, multiplex ligation-dependent probe amplification (MLPA), and exome sequencing. Ten heterozygous variants were detected in COL4A3 or COL4A4 in nine patients via Sanger sequencing, three of which were novel variants. The diagnostic rate of "likely pathogenic" or "pathogenic" under the American College of Medical Genetics and Genomics guidelines was 53.8% (7 out of 13 patients). There were eight single nucleotide variants, seven of which were glycine substitutions in the collagenous domain, one of which was a splice-site single nucleotide variant, and two of which were deletion variants. One patient had digenic variants in COL4A3 and COL4A4. While MLPA analyses showed negative results, exome sequencing identified three heterozygous variants in causative genes of FSGS in four patients with no apparent variants on Sanger sequencing. Since patients with heterozygous mutations of COL4A3 or COL4A4 showed a wide spectrum of disease from TBMN to ADAS, careful follow-up will be necessary for these patients.

Elevated serum levels of bromine do not always indicate pseudohyperchloremia.

BACKGROUND: We encountered a case of bromism that was found to be due to pseudohyperchloremia. Hyperchloremia is known to be able to reveal existing bromism, but the fact that bromine (Br(-)) influences chloride (Cl(-)) in assays that use ion electrode machines is not widely known. METHODS: We assayed samples by an ion electrode method, using four types of machines. Different amounts of Cl(-) or Br(-) were added to each sample. RESULTS: With the addition of Cl(-) to the samples, the assayed Cl(-) concentrations were proportional to the amount of added Cl(-). With the addition of Br(-) to the samples, the assayed Cl(-) concentrations, as measured by all machines, were increased, but the amounts of the increase differed significantly, and were not proportional to the amount of Br(-) added. In particular, in the machine most markedly influenced by additional Br(-), the Cl(-) concentrations increased from 94.9 to 139.6 mEq/l with the addition of 10 mEq/l of Br(-). Conversely, in the least influenced machine, Cl(-) values increased from 95.0 to 103.0 mEq/l with the addition of 10 mEq/l of Br(-). CONCLUSION: The influence on the Cl(-) assay of the addition of Br(-) varied significantly between different ion electrode machines. Clinical nephrologists therefore need to be able to recognize the characteristics of the specific machines used in their hospitals.

A Kidney Transplant Recipient with Recurrent Henoch-Schönlein Purpura Nephritis Successfully Treated with Steroid Pulse Therapy and Epipharyngeal Abrasive Therapy.

There is no specific treatment for recurrent Henoch-Schönlein purpura nephritis (HSPN) in a transplanted kidney. We herein report a case of a kidney transplant recipient with recurrent HSPN that was successfully treated with steroid pulse therapy and epipharyngeal abrasive therapy (EAT). A 39-year-old Japanese man developed HSPN 4 years ago and had to start hemodialysis after 2 months despite receiving steroid pulse therapy followed by oral prednisolone, plasma exchange therapy, and cyclophosphamide pulse therapy. He had undergone tonsillectomy 3 years earlier in the hopes of achieving a better outcome of a planned kidney transplantation and received a living-donor kidney transplantation from his mother 1 year earlier. Although there were no abnormalities in the renal function or urinalysis 2 months after transplantation, a routine kidney allograft biopsy revealed evidence of mesangial proliferation and cellular crescent formation. Mesangial deposition for IgA and C3 was noted, and he was diagnosed with recurrent HSPN histologically. Since the renal function and urinalysis findings deteriorated 5 months after transplantation, 2 courses of steroid pulse therapy were performed but were ineffective. EAT using 0.5% zinc chloride solution once per day was combined with the third course of steroid pulse therapy, as there were signs of chronic epipharyngitis. His renal function recovered 3 months after daily EAT and has been stable for 1.5 years since transplantation. Daily EAT continued for >3 months might be a suitable strategy for treating recurrent HSPN in cases of kidney transplantation.

How long is strict bed rest necessary after renal biopsy?

BACKGROUND: No consensus exists on the amount of bed rest required after renal biopsy. Moreover, forced prolonged bed rest can be uncomfortable in patients undergoing renal biopsy. OBJECTIVE: To evaluate whether the length of strict bed rest affects the incidence of pain and other complications after renal biopsy. STUDY DESIGN, FACILITY, AND PATIENTS: This single-center retrospective observational study was conducted in 94 consecutive patients undergoing biopsy of a native kidney between November 2005 and December 2006 at Mie University Hospital. The control group was composed of 317 patients who underwent biopsy of a native kidney between January 2001 and October 2005. METHODS: The incidence of biopsy-related complications was compared between two periods of strict bed rest: 2 h of strict bed rest with no abdominal bandage (November 2005 to December 2006) and 7 h of strict bed rest with an abdominal bandage (January 2001 to October 2005). The primary outcome was the incidence of back pain requiring analgesics. The secondary outcomes were: need for transfusion or hemostatic intervention, decrease of >/=10% in hemoglobin (Hb) after biopsy, macroscopic hematuria, infection possibly related to biopsy, need for single or indwelling bladder catheterization, and other biopsy-related complications. RESULTS: The incidence of back pain requiring analgesics decreased with a shorter period of strict bed rest [7.5% versus 21.1%, odds ratio (OR) 0.30, 95% confidence interval (95% CI) 0.12-0.64, p = 0.004]. Even after adjustment for age, sex, perinephric hematoma size, and number of biopsy punctures, the incidence of back pain decreased significantly (OR 0.34, 95% CI 0.14-0.73, p = 0.01). With a shorter period of strict bed rest, there were no significant differences in bleeding complications (need for transfusion or other hemostatic intervention), decrease of >or=10% in Hb or macroscopic hematuria. However, the need for indwelling bladder catheterization decreased significantly (36.2% versus 50.5%, OR 0.55, 95% CI 0.34-0.88, p = 0.013). CONCLUSIONS: Shortening the period of strict bed rest after renal biopsy from 7 h to 2 h decreased the incidence of back pain, but there was no increase in bleeding or other biopsy-related complications. Our findings suggest that a shorter period of strict bed rest can safely reduce discomfort in renal biopsy patients.

Improvement of Alveolar Hemorrhaging in an Elderly and Renally Impaired Patient with Relapsing Anti-neutrophil Cytoplasmic Autoantibody-associated Vasculitis by Single Infusion of Rituximab.

Rituximab (RTX) has become a therapeutic option for inducing remission of anti-neutrophil cytoplasmic autoantibody-associated vasculitis (AAV). However, the optimum dosage of RTX to induce remission of AAV and reduce adverse events, such as infection, remains unclear. We herein report an elderly and renally impaired patient with alveolar hemorrhaging due to refractory AAV who was successfully treated with single infusion of RTX. Single infusion of RTX may be a therapeutic option in refractory AAV patients who are vulnerable to infections.

Clinical Manifestation of Patients With Atypical Hemolytic Uremic Syndrome With the C3 p.I1157T Variation in the Kinki Region of Japan.

The gain-of-function variation p.I1157T in C3 was previously identified in 8 patients with atypical hemolytic uremic syndrome (aHUS) at Mie University Hospital. In the present study, we identified another 11 patients with aHUS with this variation, including 10 pediatric patients (onset age: 1-16 years). The variation seems to be geographically concentrated around Mie Prefecture in Japan. Fifteen of the 19 patients with aHUS experienced infection as probable triggering events. All 19 patients had renal dysfunction. Seven patients, including 2 from the previous study and 5 from the present study, were treated with eculizumab, with all showing a good response with hematological normalization. Among the 5 eculizumab-treated patients in the present study, 3 had an ambiguous diagnosis of aHUS due to low-grade hemolysis even with elevated levels of lactate dehydrogenase and bilirubin. In those cases, in-house targeted DNA sequencing identified the C3 p.I1157T variation carriers, which enabled the early initiation of treatment with eculizumab. The present study supports the early introduction of eculizumab in patients with aHUS, especially pediatric patients.

Anti-albuminuric effect of losartan versus amlodipine in hypertensive Japanese patients with type 2 diabetes mellitus: A prospective, open-label, randomized, comparative study.

UNLABELLED: Abstract. BACKGROUND: The antiproteinuric effect of the angiotensin II receptor-antagonist losartan has been observed in patients with type 2 diabetes mellitus (T2DM). Proteinuria is considered to be a predictor of the progression of kidney disease. OBJECTIVE: The aims of the present study were to compare and examine the ability of losartan and amlodipine to ameliorate albuminuria in hypertensive Japanese patients (systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg) with T2DM and whether the change in albuminuria was associated with a change in glomerular filtration rate (GFR). METHODS: This prospective, open-label, randomized, comparative study was conducted over 3 months at the Kinki University School of Medicine, Osaka-Sayama, Japan. Hypertensive patients with T2DM were enrolled and randomly assigned to 1 of 2 study groups receiving either losartan (25-100 mg/d) or the calcium channel-blocker amlodipine (2.5-5 mg/d). Urinary albumin excretion (UAE), creatinine clearance, and GFR were recorded at study initiation (baseline) and study end (month 3). The GFR was measured from the fractional renal accumulation of (99m)Tc-diethylenetriaminepentaacetic acid. Adverse events (AEs) were monitored by a clinical research nurse during the examination. RESULTS: Fifty patients were asked to enroll and 38 returned the informed written consent. Thirty-five Japanese patients were included in the final study analysis. Seventeen patients were assigned to the losartan group (male sex, 10 [58.8%]; mean [SD] age, 58.1 [8.2] years) and 18 were assigned to the amlodipine group (male sex, 10 [55.6%]; mean [SD] age, 57.4 [8.9] years); no significant between-group difference in demographics was observed. A significant decrease from baseline to month 3 of mean (SD) UAE was observed in the losartan group (352.5 [556.6] mg/d vs 275.7 [466.1] mg/d; P = 0.048). No significant difference in mean (SD) UAE was observed in the amlodipine group for the same time period (298.2 [416.6] mg/d vs 322.7 [415.4] mg/d). There was a statistically significant difference found in the mean (SD) percent change of UAE from baseline to month 3 in the losartan group compared with the amlodipine group (-23.52 [28.42] vs +27.90 [63.51]; P = 0.004). Neither group was associated with a significant change in GFR during the course of the study. No patient discontinued the study due to AEs that were considered, by the investigator, to be possibly or probably associated with study treatment. CONCLUSIONS: Treatment with losartan, but not amlodipine, was associated with a reduction in albuminuria in these hypertensive Japanese patients with T2DM within a period as short as 3 months. Neither drug was associated with a significant change in GFR. Therefore, the reduction of UAE was independent of a change in the GFR.

Tocilizumab for uncontrollable systemic inflammatory response syndrome complicating adult-onset Still disease: Case report and review of literature.

RATIONALE: Adult-onset Still disease (AOSD) is a rare systemic inflammatory disease of unknown etiology characterized by evanescent salmon-pink rash, fever spikes, arthralgia, and lymphadenopathy. AOSD usually has a good prognosis, but it can sometimes be fatal, especially when it is complicated by systemic inflammatory response syndrome (SIRS) and multiple organ failure. PATIENT CONCERNS: A previously healthy 26-year-old woman was referred to our hospital for persistent high fever and mild systemic edema. Five days later, the patient presented with dyspnea, hypotension, and anuria. Anasarca developed with massive pleural effusion, ascites, and systemic edema, resulting in an increase of 47 kg in body weight. DIAGNOSES: The patient was diagnosed as AOSD after infection, malignancy, hematologic disorders, and other autoimmune diseases were excluded. INTERVENTIONS: We administered tocilizumab, an IL-6 receptor inhibitor, intravenously in addition to cyclosporine, prednisolone, plasma exchange, and continuous hemodiafiltration. OUTCOMES: The patient's systemic condition improved. After stabilization by all medications, the patient was managed and responded to tocilizumab alone. To the best of our knowledge, this was the first case of severe SIRS complicating AOSD that was successfully treated with an anti- IL-6 receptor antibody. LESSONS: SIRS should not be overlooked in a patient with steroid-resistant AOSD and edema. Inhibitors of the IL-6 receptor can be used safely and effectively to control AOSD complicated with severe SIRS.

Severe Intimal Thickening of Interlobular Arteries Revealed by a Renal Biopsy in an Adult with Prader-Willi Syndrome Complicated by IgA Nephropathy.

Renal complications are rare in patients with Prader-Willi syndrome (PWS). We herein experienced a 31-year-old woman with PWS, in whom a renal biopsy showed IgA nephropathy and severe intimal thickening of the interlobular arteries. The patient was admitted to our hospital due to proteinuria and microscopic hematuria after an upper respiratory infection. The occurrence of cardiovascular events has been reported as a cause of death in obese PWS patients. Because chronic kidney disease is generally a risk factor for cardiovascular disease, early detection checkups are essential in obese PWS patients to monitor the possible development of cardiovascular disease.