Proteolytic cleavage of Podocin by Matriptase exacerbates podocyte injury.

Podocyte injury is a critical step toward the progression of renal disease and is often associated with a loss of slit diaphragm proteins, including Podocin. Although there is a possibility that the extracellular domain of these slit diaphragm proteins can be a target for a pathological proteolysis, the precise mechanism driving the phenomenon remains unknown. Here we show that Matriptase, a membrane-anchored protein, was activated at podocytes in CKD patients and mice, whereas Matriptase inhibitors slowed the progression of mouse kidney disease. The mechanism could be accounted for by an imbalance favoring Matriptase over its cognate inhibitor, hepatocyte growth factor activator inhibitor type 1 (HAI-1), because conditional depletion of HAI-1 in podocytes accelerated podocyte injury in mouse model. Matriptase was capable of cleaving Podocin, but such a reaction was blocked by either HAI-1 or dominant-negative Matriptase. Furthermore, the N terminus of Podocin, as a consequence of Matriptase cleavage of Podocin, translocated to nucleoli, suggesting that the N terminus of Podocin might be involved in the process of podocyte injury. Given these observations, we propose that the proteolytic cleavage of Podocin by Matriptase could potentially cause podocyte injury and that targeting Matriptase could be a novel therapeutic strategy for CKD patients.

Identification of children with chronic kidney disease through school urinary screening using urinary protein/creatinine ratio measurement: an observational study.

BACKGROUND: School urinary screening has been performed in Japan. METHODS: Ikeda City and Toyono Town introduced, in 2012 and 2013, urinary protein/creatinine (Cr) ratio measurement into the urine-screening protocols designed for students aged between 4 and 15 years. For each student whose urinary protein/Cr ratio was ≥ 0.15 g/gCr (positive case), an appointment was made with a specialist at Ikeda City Hospital. The results of these screening urinalyses conducted through 2018 are summarized. RESULTS: 14,606 junior high and elementary school students aged between 6 and 15 years were included. On average, they underwent 4.16 screening tests. 77 positive cases were detected, and seven students were diagnosed with high-risk chronic kidney disease (CKD). Of these, four underwent renal biopsy, and two, one, and one were diagnosed with IgA nephropathy, MPGN, and FSGS, respectively. In three students, detection of CKD would have been difficult without urinary screening. Incident rates of high-risk CKD and IgA nephropathy are estimated as 11.5 and 3.3 cases/100,000 students/year. 78.0% of positive cases without high-risk CKD showed no urinary abnormality after one year. 2301 kindergarten students aged between 4 and 6 years received an average of 1.74 screening urinalyses; none was positive or high-risk CKD. The estimated cost of detecting one high-risk CKD student whose detection would have been difficult without this screening was 3,156,711 Japanese yen. CONCLUSION: School urinary screening using the urinary protein/Cr ratio can efficiently refer to a specialist. It detects a few children with high-risk CKD early with spending high cost.

Renal impairment during the treatment of telaprevir with peginterferon and ribavirin in patients with chronic hepatitis C.

AIM: Renal damage has been reported as an important complication during combination treatment of peginterferon (PEG IFN), ribavirin (RBV) and telaprevir (TVR) for chronic hepatitis C. However, very little is known about this complication. We investigated the role TVR plays in renal damage during this triple therapy. METHODS: Twenty-five chronic hepatitis C patients with genotype 1 and high viral load received TVR in combination with PEG IFN and RBV for 12 weeks followed by treatment with PEG IFN and RBV. Renal function of these patients was prospectively evaluated for 16 weeks. RESULTS: Creatinine clearance decreased significantly during PEG IFN/RBV/TVR treatment. Consequently, serum creatinine and cystatin C significantly rose during PEG IFN/RBV/TVR treatment. Serum creatinine returned to pretreatment levels after the termination of TVR. The increase of serum creatinine and cystatin C from baseline significantly correlated with serum TVR level at day 7, which was determined by starting dose of TVR per bodyweight . When the patients were classified according to the starting dose of TVR per bodyweight, renal impairment was observed only in the high-dose (TVR ≥33 mg/kg per day) group, not in the low-dose (TVR <33 mg/kg per day) group. CONCLUSION: These results suggest that TVR dose per bodyweight is important for the occurrence of renal impairment in PEG IFN/RBV/TVR treatment.

Anticipated deaths with physician care (mitori) at home in one town in Japan: A preliminary report.

Background: There are few reports on the numbers of anticipated deaths (mitori [り]) at home in Japan. Method: We used the Japanese death certificate system (shiboukohyou []) for Toyono town citizens who died between 2020 and 2022 and judged a death to constitute mitori when the certificate was not written by a doctor referred from the police. Results: Among 756 deaths, 109 (14.4%) were mitori at home. Deaths at home were 144 and mitori at home accounted for 75.7%. Conclusion: Shiboukohyou appear to provide numbers of mitori at home. Death certificate should include a space which shows mitori or not.

Withdrawal of Glucocorticoid Therapy is Difficult in Women with Polymyalgia Rheumatica: An Observational Study.

OBJECTIVE: A total of 105 patients (64 women) who were started on glucocorticoid (GC) treatment for polymyalgia rheumatica (PMR) and/or remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome at Ikeda City Hospital from July 2004 to December 2019 were reviewed (PMR: 81, overlap: 20, pure RS3PE syndrome: 4). Then, 32 cases that had stopped GC and 17 cases that had continued GC for 7.5 years or longer were evaluated (women:men, stopped GC 12:20, continued GC 13:4, respectively) (PMR:overlap:pure RS3PE syndrome, stopped GC 26:6:0, continued GC 14:2:1, respectively). METHODS: The GC continuation rate in all patients was examined using the Kaplan-Meier method. The following were compared between the two groups: age at starting GC; sex; erythrocyte sedimentation rate, C-reactive protein, hemoglobin, ferritin, aspartate aminotransferase, and alanine aminotransferase before starting GC; days from the onset of symptoms to GC initiation; GC maximum dose; GC dose half a year after its start; presence of relapse; and existence of concomitant malignant disease. RESULTS: The GC continuation rate 7.5 years after GC initiation was 52.5%, higher in women (69.2%), than in men (27.1%). The rates then remained unchanged for 15 years. Hemoglobin was high, and relapse was uncommon in the group that stopped GC. There were no differences in other items. CONCLUSION: It is difficult to stop GC therapy for PMR in women in Japan, especially in cases with severe anemia.

A double-lumen catheter for hemodialysis dislocated into the mediastinum.

The insertion of a catheter into the mediastinum can occur in any patient as a complication. We must check for blood regurgitation not only in the blood removal line but also in the blood return line.

Case report: Gastric cancer-associated membranous nephropathy that recurred after complete remission and formation of peritoneal dissemination.

Membranous nephropathy associated with malignant neoplasm may remit completely with treatment of the underlying disease. In such cases, recurrence is very rare. However, after a recurrence, attention should be paid to the possible recurrence of the underlying disease.

Sjögren's syndrome concurrent with protein-losing gastroenteropathy with secondary systemic capillary leak syndrome : A case report.

Sjögren's syndrome concurrent with protein-losing gastroenteropathy can develop into secondary systemic capillary leak syndrome. Thus, it is important to diagnose the condition as soon as possible and simultaneously administer treatment for Sjögren's syndrome, protein-losing gastroenteropathy, and systemic capillary leak syndrome.

First-visit patients without a referral to the Department of Internal Medicine at a medium-sized acute care hospital in Japan: an observational study.

PURPOSE: We sought to profile first-time patients without a referral who sought medical care at the Department of Internal Medicine at a medium-sized acute care hospital in Japan. We anticipated that the analysis would highlight the demand for medical care needs from acute care hospitals and help confirm one of the problems associated with primary care in Japan. PATIENTS AND METHODS: The study population comprised 765 patients who sought outpatient consultation without a referral at "the Department of General Internal Medicine" at the Ikeda City Hospital on Fridays over 4 years. Data on the following variables were collected: age, sex, examination date, reason for encounter (RFE), diagnosis, as well as history of consultation with or without antibiotic treatment at another medical institution for the same RFE. We used the International Classicication of Primary Care, Revised Second edition (ICPC-2-R) codes for RFEs and diagnoses. RESULTS: The main RFE fields were digestive (ICPC-2-R Chapter D), general and unspecified (A), and respiratory (R). The main diagnosis fields were digestive (D), respiratory (R), general and unspecified (A), and musculoskeletal (L). In total, 27.6% of patients had sought consultation at another medical institution for the same RFE. Of these, 64.7% of patients for whom the RFE was cough (ICPC-2-R code, R05), and 72.0% for whom the RFE was fever (A03) were prescribed antibiotics. In total, 62.4% of patients underwent emergency investigations and waited for the results; 4.3% were hospitalized on the same day; and 60.5% were medicated at the initial examination. In 11.5%, the main underlying problem appeared to be psychosomatic. CONCLUSION: We used the ICPC-2-R to analyze the state of first-visit patients without a referral visiting the Department of Internal Medicine at a medium-sized acute care hospital in Japan. Common RFEs were abdominal pain, cough, and fever. A tendency toward overprescription of antibiotics was observed among primary care physicians.

Impaired Podocyte Autophagy Exacerbates Proteinuria in Diabetic Nephropathy.

Overcoming refractory massive proteinuria remains a clinical and research issue in diabetic nephropathy. This study was designed to investigate the pathogenesis of massive proteinuria in diabetic nephropathy, with a special focus on podocyte autophagy, a system of intracellular degradation that maintains cell and organelle homeostasis, using human tissue samples and animal models. Insufficient podocyte autophagy was observed histologically in patients and rats with diabetes and massive proteinuria accompanied by podocyte loss, but not in those with no or minimal proteinuria. Podocyte-specific autophagy-deficient mice developed podocyte loss and massive proteinuria in a high-fat diet (HFD)-induced diabetic model for inducing minimal proteinuria. Interestingly, huge damaged lysosomes were found in the podocytes of diabetic rats with massive proteinuria and HFD-fed, podocyte-specific autophagy-deficient mice. Furthermore, stimulation of cultured podocytes with sera from patients and rats with diabetes and massive proteinuria impaired autophagy, resulting in lysosome dysfunction and apoptosis. These results suggest that autophagy plays a pivotal role in maintaining lysosome homeostasis in podocytes under diabetic conditions, and that its impairment is involved in the pathogenesis of podocyte loss, leading to massive proteinuria in diabetic nephropathy. These results may contribute to the development of a new therapeutic strategy for advanced diabetic nephropathy.

Two brothers with collagenofibrotic glomerulopathy.

Collagenofibrotic glomerulopathy is a rare glomerular disease characterized by extensive accumulation of atypical type III collagen fibers within the mesangial matrix and subendothelial space. Laboratory evaluation of this disease shows a marked increase in serum procollagen III peptide (P III P) levels. Here, we report the case of two brothers with collagenofibrotic glomerulopathy confirmed by histology. Patient 1 presented with proteinuria and hypertension and patient 2 presented with nephrotic-range proteinuria. Immunohistochemistry revealed strong staining for antibodies to type III collagen in the widened subendothelial spaces in both patients. Electron microscopy revealed numerous collagenous fibers in the mesangium and subendothelial space. P III P levels were elevated in both patients. Most reported cases of collagenofibrotic glomerulopathy, including the adult-onset type, have been sporadic. Within the limits of our literature search, this is only the third report of adult siblings with collagenofibrotic glomerulopathy confirmed by histology. This report indicates that it may be beneficial to measure serum P III P levels in the siblings of patients diagnosed with adult-onset collagenofibrotic glomerulopathy.

Restructuring the Ikeda City school urinary screening system: report of a screening survey.

BACKGROUND: Annual urinary screening is conducted at municipal kindergartens, elementary schools, and junior high schools in Ikeda City, Osaka, Japan (Ikeda City School System), and the results are reviewed by a general physician, but standards for when to recommend specialist referral have not been clear. METHODS: In all children attending the Ikeda City School System in 2012, dipstick urinalysis of a first-morning urine specimen was recommended once or twice, and if a second urinalysis showed proteinuria (≥1+), the urinary protein/creatinine ratio was measured. If this showed ≥0.2 g/g of creatinine (g/gCr), it was recommended that the child be evaluated by a specialist at Ikeda City Hospital. RESULTS: Urinary screening was performed in about 20% (388) of kindergarten, about 90% (5363) of elementary school, and about 86% (2523) of junior high school children living in Ikeda City. Urine samples were obtained from 387, 5349, and 2476 children, respectively. The urinary protein/creatinine ratio was ≥0.2 g/gCr in 13 children, including 1 elementary and 12 junior high children. In these 13 children, chronic nephritic syndrome (CNS) was suspected in 6 junior high school children, and of these, this was a new finding in 5, and renal biopsy was indicated in 3. In Ikeda City, the prevalence of CNS in elementary school children was <0.03%, the prevalence of CNS in junior high school children was 0.29%, and a renal biopsy was indicated in 0.14%. By eliminating the costs associated with assessment of the results by the Ikeda Medical Association, and by directly contracting with the testing company, the expenses paid by Ikeda City for the system itself decreased from 2,508,619 yen to 966,157 yen. CONCLUSIONS: Incorporating the urinary protein/creatinine ratio into the school urinary screening system in the Ikeda City School System and clarifying standards for specialist referral has enabled restructuring of the system so that is efficient and its effectiveness can be assessed.