A Case of Atypical Hemolytic Uremic Syndrome Triggered by Acute Pancreatitis in a Patient with a Membrane Cofactor Protein (CD46) Genetic Variant.

Atypical hemolytic uremic syndrome (aHUS) is a type of HUS. We herein report a case of aHUS triggered by pancreatitis in a patient with a heterozygous variant of membrane cofactor protein (MCP; P165S), a complement-related gene. Plasma exchange therapy and hemodialysis improved thrombocytopenia and anemia without leading to end-stage kidney disease. This MCP heterozygous variant was insufficient to cause aHUS on its own. Pancreatitis, in addition to a genetic background with a MCP heterozygous variant, led to the manifestation of aHUS. This case supports the "multiple hit theory" that several factors are required for the manifestation of aHUS.

Acute Tubulointerstitial Nephritis in Rosai-Dorfman Disease Mimicking IgG4-related Disease.

Rosai-Dorfman-Destombes disease (RDD) is a non-Langerhans cell histiocytosis characterized by the accumulation of histiocytes inside the lymph nodes or extranodally. The association between RDD and IgG4-related disease (IgG4-RD) is discussed. We herein report a case of RDD manifesting as acute tubulointerstitial nephritis mimicking IgG4-RD. The first renal biopsy showed severe tubulointerstitial nephritis with infiltration of S100-positive histiocytes and IgG4-positive plasma cells; storiform fibrosis and obliterative phlebitis were not confirmed. After prednisolone therapy, IgG4-positive cells and S100-positive histiocytes were decreased, but the IgG4/IgG ratio increased despite clinical improvement. These findings indicated extranodal RDD in the kidney presenting as tubulointerstitial nephritis.

Two episodes of acute dyspnea that were induced by COVID-19 in a peritoneal dialysis patient.

Dialysis patients have an increased risk of coronavirus disease 2019 (COVID-19)-related mortality. Acute heart failure is a frequent, lethal complication of COVID-19, and it is a risk factor for mortality in hemodialysis patients. Therefore, it is crucial to rapidly distinguish heart failure from COVID-19 pneumonia. Here, we report a case of two episodes of acute dyspnea that were induced by COVID-19 in a peritoneal dialysis (PD) patient. The first episode of acute dyspnea was an exacerbation of heart failure caused by COVID-19 when the patient had a volume overload status due to a peritoneal dialysis catheter malfunction. Heart failure induced by a catheter malfunction was due to omental wrapping, and it was treated with ultrafiltration by hemodialysis and mini-laparotomy. The patient's acute dyspnea was immediately resolved. The second episode of acute dyspnea was caused by COVID-19 pneumonia, which occurred 1 week after the first episode. This case suggests the importance of identifying heart failure and beginning adequate treatment, in COVID-19 patients with PD.

Successful treatment with assisted automated peritoneal dialysis using 4.25% glucose dialysate for an elderly patient with refractory heart failure.

Refractory heart failure is a major cause of mortality and hospitalization, and peritoneal dialysis (PD) is one of the options for controlling volume overload. Although high glucose dialysate enables a large amount of ultrafiltration, the use of 4.25% glucose dialysate is generally avoided, because high glucose exposure leads to peritoneal damage. Here, we describe a patient who was successfully treated with assisted automated PD using 4.25% glucose dialysate for refractory heart failure. An 84-year-old woman developed heart failure due to severe mitral regurgitation with a low left-ventricular ejection fraction of 30%, and also developed progressive kidney deterioration. She had been refractory to diuretics and repeatedly hospitalized. PD was started to treat refractory heart failure. Since it was difficult for her to change the dialysis bags by herself, assistance with her PD from her family was needed. The use of 4.25% glucose dialysate markedly increased ultrafiltration and improved her condition. In addition, automated PD (APD) using 4.25% glucose dialysate enabled her family to have a break from PD once every 4 days. Thereafter, she had no episodes of hospitalization due to heart failure for approximately 18 months after her discharge.

A novel splice-site mutation of the HNF1B gene in a family with maturity onset diabetes of the young type 5 (MODY5).

SUMMARY: Maturity-onset diabetes of the young (MODY) is a form of monogenic diabetes mellitus characterised by early onset and dominant inheritance. Delayed diagnosis or misdiagnosis as type 1 or type 2 diabetes mellitus is common. Definitive genetic diagnosis is essential for appropriate treatment of patients with MODY. The hepatocyte nuclear factor 1-beta (HNF1B) gene is responsible for MODY type 5 (MODY5), which has distinctive clinical features including renal disease. MODY5 should always be considered by clinicians in patients with early onset diabetes and renal anomalies. We report a case of a 30-year-old Japanese male with early-onset diabetes mellitus, renal anomalies and family history of diabetes that was suggestive of MODY5. Renal histology showed no evidence of diabetic nephropathy. Genetic testing revealed a novel heterozygous splice-site mutation of the HNF1B gene in the family members. It was strongly suggested that the mutation could underlie our patient's MODY5. LEARNING POINTS: Genetic diagnosis of MODY is relevant for appropriate treatment. Dominantly inherited early-onset diabetes mellitus with renal cysts suggests MODY5. Scanning the non-coding regions is important for not missing a mutation in HNF1B.

A case of nephrotic syndrome showing contemporary presence of apolipoprotein E2 homozygote glomerulopathy and membranous nephropathy-like findings modified by apolipoprotein E Toyonaka.

A 79-year-old man was admitted to our hospital for proteinuria due to nephrotic syndrome. Renal biopsy revealed focal sclerosis and foam cell infiltration in the glomerulus. In addition, electron microscopic findings (EM) revealed peculiar electron-dense deposits (EDDs) in both sides of the glomerular basement membrane. Although subepithelial deposits had spike formation highly resembling those seen in membranous nephropathy (MN), immunoglobulins and complements were not identified by immunofluorescence study, and microbubbles appeared in high magnification of EM different from the immune disease. The analysis of apolipoprotein (Apo) E showed an elevated concentration of plasma ApoE. The phenotype, genotype, and DNA sequence studies revealed homozygous ApoE2/2 and a novel missense mutation called ApoE Toyonaka (Ser197Cys). This case may confirm the independent responsibility of ApoE2/2 and ApoE Toyonaka for ApoE2 homozygote glomerulopathy and MN-like EDD findings, respectively.

An integrative study of the genetic, social and environmental determinants of chronic kidney disease characterized by tubulointerstitial damages in the North Central Region of Sri Lanka.

OBJECTIVES: Previous investigations on chronic kidney disease of unknown etiology characterized by tubulointerstitial damages (CKDu) in the North Central Region (NCR) of Sri Lanka have supported the involvement of social, environmental and genetic factors in its pathogenesis. METHODS: We conducted a social-environmental-and-genetic epidemiology study on a male population in NCR to investigate the genetic and environmental contributors. We recruited 311 case-series patients and 504 control candidates. Of the 504 control candidates, 218 (43%) were eliminated because of the presence of hypertension, proteinuria, high HbA1c, high serum creatinine or high alpha-1 microglobulin in urine. RESULTS AND DISCUSSION: None of 18 metals measured (µg//) in urine, including Cd, As and Pb, showed significantly higher concentrations in cases compared with controls. As speciation results showed that 75-80% of total urinary As was in the form of arsenobetaine, which is non-toxic to humans. None of the metal concentrations in drinking water samples exceeded guideline values. A genome-wide association study (GWAS) was conducted to determine the genetic contributors. The GWAS yielded a genome-wide significant association with CKDu for a single nucleotide polymorphism (SNP; rs6066043; p=5.23 × 10(-9) in quantitative trait locus analysis; p=3.73 × 10(-9) in dichotomous analysis) in SLC13A3 (sodium-dependent dicarboxylate transporter member 3). The population attributable fraction and odds ratio for this SNP were 50% and 2.13. Genetic susceptibility was identified as the major risk factor for CKDu. However, 43% of the apparently healthy male population suffers from non-communicable diseases, suggesting their possible influence on CKDu progression.

[Case of pseudohypercreatininemia associated with monoclonal IgM gammopathy].

An 80-year-old man with well controlled hypertension for eight years and monoclonal IgM gammopathy was referred to our hospital in May 2010 due to persistent elevation of serum creatinine(s-Cr). At our hospital, urine and blood tests showed no abnormal findings as BUN and Cr were 15.0 mg/dL and 0.91 mg/dL, respectively. In contrast the referring hospital had obtained values of 10.4 mg/dL and 4.8 mg/dL, respectively. This discrepancy was replicated when s-Cr was measured in another sample from this patient using the enzyme assay kits employed by the referring hospital and our hospital. High-performance liquid chromatography (HPLC), which is the standard method for measuring s-Cr, gave a value in the normal range. After removing high molecular weight proteins (>3,000 D)from the serum sample, the s-Cr levels measured with the respective kits were similar. Since elevation of s-Cr was linked to that of IgM at the referring hospital, we diagnosed the patient as having pseudohypercreatininemia with monoclonal IgM gammopathy.

Evaluation of the newly proposed simplified histological classification in Japanese cohorts of myeloperoxidase-anti-neutrophil cytoplasmic antibody-associated glomerulonephritis in comparison with other Asian and European cohorts.

The prognostic value of renal biopsy in anti-neutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis is widely recognized; however, there is no consensus regarding its pathological classification. Berden et al. proposed a new classification of glomerulonephritis in ANCA-associated vasculitis (AAV) categorized into focal, crescentic, mixed, and sclerotic classes and showed its prognostic value in 100 international multicenter cohorts for 1- and 5-year renal outcomes. In order to evaluate whether this new classification has predictive value and reproducibility in Japanese AAV cases, 87 cohorts with only microscopic polyangiitis in 3 limited centers in Japan were analyzed. In addition, those from Japan, Europe (Berden's cohorts) and China were compared in a recent report.

[A case of hypomagnesemia linked to refractory hypokalemia and hypocalcemia with short bowel syndrome].

We report a case of a 59-year old Japanese woman with short bowel syndrome, whose hypokalemia and hypocalcemia were successfully treated with magnesium (Mg) supplementation. Two years previously, she underwent Mile's operation for advanced rectal cancer, which could have been the cause of subsequent extensive resection of the small intestine by strangulation. After serial resection, she gradually developed chronic diarrhea and anorexia. Three weeks before admission, she developed general fatigue and tetany, and was hospitalized at another hospital. On admission, her serum K and Ca were 2.5 mEq/L and 4.3 mg/dL, respectively, hence regular fluid therapy containing potassium (K) and calcium (Ca) was provided following admission. However, her hypokalemia and hypocalcemia persisted, and she also displayed renal dysfunction and thereafter was transferred to our department for further evaluation and treatment. Since the laboratory tests revealed severe hypomagnesemia (0.4 mg/dL), we started intravenous Mg supplementation together with fluid therapy containing K and Ca. After the combination therapy, her clinical symptoms and electrolyte disorders were remarkably improved within a week. As Mg is essential for PTH secretion in response to hypocalcemia and to inhibit the K channel activity that controls urinary K excretion, hypomagnesemia can cause hypocalcemia and hypokalemia, which is refractory to repletion therapy unless Mg is administered. Therefore, for patients who present with signs of Mg deficiency, early and accurate diagnosis of Mg deficiency should be made and corrected.

Risk factors associated with disease progression and mortality in chronic kidney disease of uncertain etiology: a cohort study in Medawachchiya, Sri Lanka.

BACKGROUND: The alarming rise in the prevalence of chronic kidney disease of uncertain etiology (CKDu) among the low socioeconomic farming community in the North Central Province of Sri Lanka has been recognized as an emerging public health issue in the country. METHODS: This study sought to determine the possible factors associated with the progression and mortality of CKDu. The study utilized a single-center cohort registered in 2003 and followed up until 2009 in a regional clinic in the endemic region, and used a Cox proportional hazards model. RESULTS: We repeatedly found an association between disease progression and hypertension. Men were at higher risk of CKDu than women. A significant proportion of the patients in this cohort were underweight, which emphasized the need for future studies on the nutritional status of these patients. CONCLUSIONS: Compared with findings in western countries and other regions of Asia, we identified hypertension as a major risk factor for progression of CKDu in this cohort.

Tubulointerstitial damage as the major pathological lesion in endemic chronic kidney disease among farmers in North Central Province of Sri Lanka.

Chronic kidney disease of uncertain etiology (CKDu) in North Central Province of Sri Lanka has become a key public health concern in the agricultural sector due to the dramatic rise in its prevalence and mortality among young farmers. Although cadmium has been suspected as a causative pathogen, there have been controversies. To date, the pathological characteristics of the disease have not been reported. Histopathological observations of 64 renal biopsies obtained at Anuradhapura General Hospital from October 2008 to July 2009 were scored according to Banff 97 Working Classification of Renal Allograft pathology. The correlations between the histological observations and clinical parameters were statistically analyzed. Interstitial fibrosis and tubular atrophy with or without nonspecific interstitial mononuclear cell infiltration was the dominant histopathological observation. Glomerular sclerosis, glomerular collapse, and features of vascular pathology such as fibrous intimal thickening and arteriolar hyalinosis were also common. Although hypertension was identified as one of the common clinical features among the cases, it did not influence the histopathological lesions in all the cases. This study concludes that tubulointerstitial damage is the major pathological lesion in CKDu. Exposure(s) to an environmental pathogen(s) should be systematically investigated to elucidate such tubulointerstitial damage in CKDu.

A case of acute rejection with adenovirus infection after ABO-incompatible kidney transplantation.

We report clinical and histopathologic findings of a case of acute rejection with adenovirus infection after kidney transplantation. A 63-yr-old woman with end-stage renal disease caused by lupus nephritis received an ABO-incompatible living kidney transplantation from her husband. On the 7th post-operative day (POD), she had fever, hematuria, and bladder irritation. Although she was treated with an antibiotic, the symptoms were not improved. We diagnosed adenovirus infection as positive with the urine shell vial method and blood PCR analysis. Cyclophosphamide was interrupted and immunoglobulin therapy was performed. However, urine output decreased and serum creatinine levels increased. An episode biopsy was performed on POD 20. We diagnosed acute antibody-mediated rejection. She was treated with plasma exchange for acute rejection and antiviral drug (rivabirin) for active adenovirus infection. However, the renal graft dysfunction was deemed irreversible and the renal graft was removed on POD 34. The graftectomy specimen showed acute rejection and acute tubular necrosis with adenovirus infection.

[Combining the use of dipstick protein and specific gravity accurately predicts pathological proteinuria in Japan].

UNLABELLED: Dipstick urine analysis is the most common and convenient examination in routine health care. The criteria for abnormal proteinuria is a level of more than (+). However, the interference of urine concentration should be considered in the judgement. OBJECTIVE: The purpose is to demonstrate the effect of the combined use of specific gravity (SG) in the dipstick judgement to evaluate pathological proteinuria in Japanese people. METHODS: The hospital laboratory database of Kitano hospital was searched for urine samples, for patients consulted at our nephrology department from Oct. 2004 to Sep. 2005 (n=1767), and simultaneously assayed for dipstick proteinuria(DSP), SG, urinary protein, urine creatinine (UC) and urinary protein-creatinine ratio (UPC ratio). To generate a model table, samples were stratified according to DSP and SG values. A DSP versus SG matrix (5 x 6)was created, and then all 30 cells were color-coded by the pathological proteinuria proportion (white: < 5%, gray: 5-95%, black: <95%). RESULTS: SG was positively associated with UC. In the patients, SG < or = 1.005 and DSP(-), 12/70 (17.1%) was > or =300 mg/gCr. Moreover in the patients, both 1.005 < SG < or = 1.010 and DSP(+/-), 21/32 (65.6%) had pathological proteinuria. We confirmed the consistency for this combination table in the urine samples of another 1111 out-patients. Moreover, the area under the curve in DSP(+/-) suggests that the patients whose SG was < or = 1.011 might have pathological proteinuria (sensitivity; 82.1%, specificity; 89.3%). CONCLUSION: We recognized that the combination of DSP and SG enhances a more accurate proteinuria judgement. DSP(- approximately +/-) in diluted urine (SG < or = 1.1011) has the potential for pathological proteinuria. Therefore, diluted urine samples should be re-examined.

Nephronophthisis complicated with hepatic fibrosis: an autopsy case with rupture of the splenic artery after renal transplantation.

Nephronophthisis (NPHP) is a disease characterized by a genetic cause of chronic renal failure in children and adolescents, complicated with several extra-renal manifestations such as retinal defect and/or liver fibrosis. Although it is difficult to establish the correct diagnosis, mutations in six genes (NPHP 1-6) have recently been identified. Here we report the case of a 25-year-old male with NPHP with congenital hepatic fibrosis. He showed microscopic hematuria and moderate proteinuria at 20 years. Renal biopsy revealed severe interstitial fibrosis, diffuse tubular atrophy and microcysts at this time with chronic kidney disease stage III (Cr 2.43 mg/dl). C3c was positive in glomeruli in direct immunofluorescent study. Although his mother belongs to a family with polycystic kidney disease, he did not have a novel genetic background of Arg585Cys mutation in exon 8 of the PKD1 gene. Magnetic resonance angiography (MRA) showed typical portal hypertension with spleno-renal shunt caused by biopsy-proven liver fibrosis. Thus, we diagnosed him as having undetermined renal cystic or tubulo-interstitial disease complicated with membranoproliferative glomerulonephritis (MPGN). Renal transplantation was performed in January 2005 after 2 years of dialysis therapy. He was transported to our emergency room because of severe abdominal pain in December 2005. A computed tomographic scan showed massive ascites, which were caused by rupture of the splenic artery. Despite full intensive care including intraluminal coiling of the ruptured aneurysm and extensive blood transfusion, we failed to rescue him on the next day. The autopsy findings revealed severe atrophy of the bilateral kidney with multiple cysts along the cortico-medullary border. Obvious portal hypertension, resulting from congenital hepatic fibrosis, could account for the rupture of the splenic artery with aneurysm formation under pressure/volume overload. This is the first report of a NPHP patient with the complication of hepatic fibrosis emerging from an ADPKD family. As it remains elusive on the phenotype-genotype of the Japanese NPHP population, a registration system of cystic disease of the kidney is required.

Clinicopathological influence of obesity in IgA nephropathy: comparative study of 74 patients.

The pathological role of obesity has rarely been studied in primary glomerular diseases. The purpose of this study is to examine the clinicopathological influence of obesity in IgA nephropathy (IgAN). 74 patients with IgA nephropathy in our institution from October 2000 to January 2004 were retrospectively divided into two groups according to body mass index (BMI): the non-obese group (group N) with BMI < 25 kg/m(2), and the obese group (group O) with BMI > or = 25 kg/m(2). There were 50 patients in group N and 24 patients in group O. Clinical analysis showed no significant difference between these two groups in blood pressure, serum cholesterol, creatinine clearances or grade of hematuria. However, urinary protein excretion and serum creatinine were significantly greater in group O than in group N. Although semiquantitative analysis of light-microscopical findings showed no significant differences in the severity of mesangial proliferation, matrix expansion, glomerulosclerosis or crescent formation, image analysis showed that total glomerular area and tuft area were significantly larger in group O. In addition, ultrastructural study revealed significantly higher glomerular basement membrane thickness in group O. 62 patients (46 patients, group N; 16 patients, group O) were followed in our institution for one year. Urinary protein was significantly decreased only in patients who received steroid in both groups. Although administration of ACE inhibitor or ARB tended to decrease urinary protein in group O, the change was not statistically significant. Our findings indicate that obesity may accelerate the increase of proteinuria in IgAN through ultrastructural modification of the glomerular basement membrane.