Exercise instruction during haemodialysis treatment after changes to the insurance regime: a nationwide questionnaire survey in Japan

In April 2022, an additional medical fee for exercise instruction during haemodialysis treatment was approved for insurance claims in Japan. We conducted a questionnaire survey to investigate the current situation regarding exercise therapy during haemodialysis treatment after this change. Questionnaires were mailed to 4257 haemodialysis facilities, almost all the haemodialysis facilities in Japan, on January 31, 2023. In total, 1657 facilities responded, of which 550 (33%) provided exercise instruction during haemodialysis treatment, and 65% of these claimed the new fee. Of the 550 facilities that had claimed the fee at the time of survey, 245 (55%) started exercise instruction in April 2022 or later. Exercise instruction focused on resistance training (81%) and aerobic exercise (62%) for 20-30 min (66%) three times a week (80%). The instructors included physicians in 45% of facilities, nurses in 74%, and physical therapists in 36%. Efficacy was evaluated in 76% of the facilities providing instruction, mainly by assessing change in muscle strength (49%). Overall, 39% of facilities had experienced some adverse events, but none were life-threatening. In conclusion, after the change in the insurance regime, exercise instruction during haemodialysis treatment has become more popular, and more patients on haemodialysis are undergoing exercise therapy.

Renal outcome of living kidney donors aged more than 70 years

BACKGROUND

The number of marginal living kidney donors has increased. Medically complex donors who have hypertension, older age, or low estimated glomerular filtration rate (eGFR) have been more likely to be used.

METHODS

We conducted a retrospective cohort study of living kidney donors at a single center. We analyzed 309 living donors and divided them into three groups: group with older donors (aged ≥70 years) (n = 41), middle-aged (aged 46-69 years) (n = 239), and young donors (aged <46 years) (N = 29). Donor factors associated with chronic kidney disease (CKD) stage 3b or worse within 5 years post-donation were investigated.

RESULTS

Of the 309 live donors, 86 (27.8%) developed CKD stage3b or worse within 5 years post-donation. The incidence of CKD stage3b or worse within 5 years post-donation was significantly higher in older donor (p < 0.01). Cox regression models revealed that older donor ages and lower eGFR were significantly related to the development of CKD stage3b or worse, independent of comorbidities such as obesity and hypertension [hazard ratio (95% CI); 4.59 (1.02-20.6), p = 047, 0.95 (0.94-0.96), p ≤ 0.01, respectively]. However, recovery of eGFR 4-5 years after donation was noted in the middle-aged and older donor groups, whereas the level of eGFR remained unchanged in the young group.

CONCLUSIONS

Older donors tend to develop CKD stage3b within 5 years post-donation but with the potential of recovery. Healthy older people (aged ≥70 years) could be candidates for living donors under careful monitoring of kidney function after donation.

Diagnostic value of 18F-fluorodeoxyglucose positron emission tomography and computed tomography for differentiating polymyalgia rheumatica and rheumatoid arthritis: Using classification and regression tree analysis

OBJECTIVES

Determining which sites were important to differentiate polymyalgia rheumatica (PMR) from rheumatoid arthritis (RA) using 18F-fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET-CT) is challenging.

METHODS

Patients with PMR or RA who were undergoing PET-CT were recruited at two mutual-aid hospitals in Japan between 2009 and 2018. Classification and regression tree (CART) analyses were performed to identify FDG uptake patterns that differentiated PMR from RA.

RESULTS

We enrolled 35 patients with PMR and 46 patients with RA. Univariate CART analysis showed that FDG uptake in the shoulder joints, spinous processes of the lumbar vertebrae, pubic symphysis, sternoclavicular joints, ischial tuberosities, greater trochanters, and hip joints differentiated PMR from RA. Multivariate CART analysis revealed that FDG uptake by at least one of the ischial tuberosities had the highest diagnostic value for distinguishing PMR from RA (sensitivity, 77.1%; specificity, 82.6%). We performed the same CART analysis to patients who had not undergone treatment (PMR, n = 28; RA, n = 9). Similar results were obtained, and sensitivity and specificity were increased (sensitivity, 89.3%; specificity, 88.8%).

CONCLUSIONS

In PET-CT, FDG uptake by at least one of the ischial tuberosities best discriminates between PMR and RA.

Health-related Quality of Life in 10 years Long-term Survivors of Chronic Kidney Disease: A From-J Study

OBJECTIVE

The Chronic Kidney Disease (CKD) practice facilitation program in the Frontier of Renal Outcome Modifications in Japan study reduced cardiovascular disease (CVD) events in patients with CKD. 10-year long-term survivors with CKD lived with serious complications, including end-stage kidney disease and CVD. This study aimed to measure health-related quality of life in 10-year long-term CKD survivors and examine the predictors and determinants of clinical indices for measured quality of life (QOL) scores.

METHODS

The EQ-5D-5L, a generic preference-based instrument, was administered to 1,473 CKD survivors enrolled in the Frontier of Renal Outcome Modifications in JapanFrontier of Renal Outcome Modifications in JapanFrontier of Renal Outcome Modifications in Japan study. The 10th-year data collection was performed by either primary care physicians or participants who filled out questionnaires from October 2018 to March 31, 2019.

RESULTS

The response rate was 38.2% (423/1,473). The mean QOL score was 0.893 (95% confidence interval (CI), 0.880-0.906), and the median QOL score was 1.000 (interquartile range (IQR), 0.826-1.000). The mean QOL score in participants with renal replacement therapy was 0.824 (95% CI, 0.767-0.881), and the median was 0.828 (IQR, 0.755-1.000). The mean QOL score in participants with CVD was 0.877 (95% CI, 0.811-0.943), and the median was 1.000 (IQR, 0.723-1.000). The mean QOL score in participants with 50% decline in estimated glomerular filtration was 0.893 (95% CI, 0.860-0.926), and the median was 0.889 (IQR, 0.825-1.000). The decrease in QOL scores with baseline CKD stages was significant according to the Jonckheere-Terpstra test for trend (P = .002). Baseline age, systolic blood pressure, and history of hyperuricemia were significant predictors of 10th-year QOL scores.

CONCLUSION

We suggest that CKD complications negatively affect the QOL scores in 10-year long-term survivors with CKD. CKD guideline-based practices, prevention of end-stage kidney disease/CVD and management of hypertension, diabetes and hyperuricemia, might contribute to future health-related quality of life in patients with CKD.

PLA2R-positive membranous nephropathy in IgG4-related disease

BACKGROUND

IgG4-related disease (IgG4-RD) is a fibroinflammatory disease that affects multiple organs, including the pancreas, lacrimal glands, salivary glands, periaortic/retroperitoneum, and kidney. Interstitial nephritis is a typical renal disorder associated with IgG4-RD, but membranous nephropathy is also seen in some cases.

CASE PRESENTATION

Herein we report on the case of a 77-year-old male patient with nephrotic syndrome and IgG4-related lung disease. His serum phospholipase A2 receptor (PLA2R) antibody was positive. His renal biopsy specimen was also positive for PLA2R. The renal biopsy specimen showed membranous nephropathy with equal IgG3 and IgG4 immunofluorescence staining and no interstitial nephritis, suggesting IgG4-RD manifesting as membranous nephropathy.

CONCLUSIONS

Nephrotic syndrome caused by membranous nephropathy is sometimes associated with IgG4-RD. In such cases, even if serum PLA2R antibody is positive, it should be considered that the membranous nephropathy may be secondary to IgG4-RD.

Factors associated with early-onset intracranial aneurysms in patients with autosomal dominant polycystic kidney disease

BACKGROUND

Recently, the importance of attribute-based medicine has been emphasized. The effects of early-onset intracranial aneurysms on patients can be significant and long-lasting. Herein, we compared the factors associated with intracranial aneurysms in patients with autosomal dominant polycystic kidney disease (ADPKD) according to age categories (≥ 50 years, < 50 years).

METHODS

We included 519 ADPKD patients, with a median age of 44 years, estimated glomerular filtration rate of 54.5 mL/min/1.73 m2, and total follow-up duration of 3104 patient-years. Logistic regression analyses were performed to determine factors associated with intracranial aneurysms.

RESULTS

Regarding the presence of intracranial aneurysm, significant interactions were identified between the age category (age ≥ 50 years), female sex (P = 0.0027 for the interaction) and hypertension (P = 0.0074 for the interaction). Female sex and hypertension were associated with intracranial aneurysm risk factors only in patients aged ≥ 50 years. The presence of intracranial aneurysm was significantly associated with chronic kidney disease (CKD) stages 4-5 (odds ratio [OR] = 3.87, P = 0.0007) and family history of intracranial aneurysm or subarachnoid hemorrhage (OR = 2.30, P = 0.0217) in patients aged < 50 years. For patients aged ≥ 50 years, in addition to the abovementioned factors [OR = 2.38, P = 0.0355 for CKD stages 4-5; OR = 3.49, P = 0.0094 for family history of intracranial aneurysm or subarachnoid hemorrhage], female sex (OR = 4.51, P = 0.0005), and hypertension (OR = 5.89, P = 0.0012) were also associated with intracranial aneurysm.

CONCLUSION

Kidney dysfunction and family history of intracranial aneurysm or subarachnoid hemorrhage are risk factors for early-onset intracranial aneurysm. Patients aged < 50 years with a family history of intracranial aneurysm or subarachnoid hemorrhage or with CKD stages 4-5 may be at an increased risk of early-onset intracranial aneurysm.

Minimum-incision transsubclavian transcatheter aortic valve replacement with balloon-expandable valve for dialysis patients

BACKGROUND

Dialysis patients undergoing transcatheter aortic valve replacement (TAVR) face increased risk and have poorer outcomes than non-dialysis patients. Moreover, TAVR in dialysis patients using an alternative approach is considered extremely risky and little is known about the outcomes. We routinely perform minimum-incision transsubclavian TAVR (MITS-TAVR), which is contraindicated for transfemoral (TF) TAVR. This study aimed to evaluate the outcomes of MITS-TAVR compared with those of TF-TAVR in dialysis patients.

METHODS

This single-center, observational study included 79 consecutive dialysis patients who underwent MITS-TAVR (MITS group, n = 22) or TF-TAVR (TF group, n = 57) under regional anesthesia.

RESULTS

The rates of peripheral artery disease (MITS vs. TF, 72.7 % vs. 26.3 %; p < 0.01), shaggy aortas (MITS vs. TF, 63.6 % vs. 5.26 %; p < 0.01), and tortuous aortas (MITS vs. TF, 13.6 % vs. 1.75 %; p = 0.031) were significantly higher in the MITS group. The 30-day mortality was 2.53 % and comparable between the two groups (MITS vs. TF, 4.54 % vs. 1.75 %; p = 0.479). In the MITS group, 14 patients had ipsilateral dialysis fistulas, and three patients had patent in situ ipsilateral internal thoracic artery grafts; however, no vascular complications were observed. Kaplan-Meier survival curves for the two groups showed no significant difference in the survival rate (at 2 years; MITS vs. TF, 77.3 % vs. 68.8 %; p = 0.840) and freedom from cardiovascular mortality (at 2 years; MITS vs. TF, 90.9 % vs. 96.5 %; p = 0.898). The multivariable Cox proportional hazard model also indicated that survival in the MITS group was not significantly different from that in the TF group (hazard ratio 1.48; 95 % confidence interval, 0.77-2.85, p = 0.244). The patency rate of ipsilateral dialysis fistula was 100 % during follow-up.

CONCLUSION

The outcome of MITS-TAVR was comparable to that of TF-TAVR in dialysis patients, despite the higher risk of patient characteristics.

Secondary spontaneous pneumothorax in a patient with resistant Mycobacterium abscessus infection and systemic sclerosis-associated interstitial lung disease: A case report

Mycobacterium abscessus subsp. abscessus (MABA) is refractory and sometimes fatal especially in an immunocompromised patient. Also, MABA-associated pneumothorax is an extremely rare complication. We report a case of MABA pulmonary infection complicated pneumothorax treated successfully. A 69-year-old Japanese female with immunosuppressed systemic sclerosis-associated interstitial lung disease experienced left-sided secondary spontaneous pneumothorax. MABA was detected in the pleural effusion and blood culture. Microbial sensitivity test showed the MABA was sensitive to only amikacin, sitafloxacin, and clofazimine. Combination therapy with these antibiotics including azithromycin achieved remission within three weeks. In the treatment of MABA infection, compliance with microbial sensitivity test is crucial.

Immediate drop of urine osmolality upon tolvaptan initiation predicts impact on renal prognosis in patients with ADPKD

BACKGROUND AND HYPOTHESIS

Tolvaptan, a vasopressin V2 receptor antagonist, is used for treating autosomal dominant polycystic kidney disease (ADPKD). We focused on changes in urinary osmolality (U-Osm) after tolvaptan initiation to determine whether they were associated with the therapeutic response to tolvaptan.

METHODS

This was a single-centre, prospective, observational cohort study. Seventy-two patients with ADPKD who received tolvaptan were recruited. We analysed the relationship between changes in U-Osm and annual estimated glomerular filtration rate (eGFR) in terms of renal prognostic value using univariable and multivariable linear regression analyses.

RESULTS

The mean value of U-Osm immediately before tolvaptan initiation was 351.8 ± 142.2 mosm/kg H2O, which decreased to 97.6 ± 23.8 mosm/kg H2O in the evening. The decrease in U-Osm was maintained in the outpatient clinic 1 month later. However, the values of U-Osm showed higher variability (160.2 ± 83.8 mosm/kg H2O) than did those in the first evening of tolvaptan administration. Multivariate analysis revealed that the baseline eGFR, baseline urinary protein, and U-Osm change in the evening of the day of admission (initial U-Osm drop) were significantly correlated with the subsequent annual change in eGFR.

CONCLUSIONS

U-Osm can be measured easily and rapidly, and U-Osm change within a short time after tolvaptan initiation may be a useful index for the renal prognosis in actual clinical practice.

Polar vasculosis is associated with better kidney outcome in type 2 diabetes with biopsy-proven diabetic kidney disease: A multicenter cohort study

AIMS/INTRODUCTION

This multicenter cohort study retrospectively assessed the association between polar vasculosis and the progression of diabetic kidney disease (DKD) in type 2 diabetes.

MATERIALS AND METHODS

We enrolled 811 patients with type 2 diabetes, biopsy-proven DKD, and proteinuria (≥0.15 g/g creatinine [g/day]). The association between polar vasculosis and other kidney lesions was explored. The outcome was DKD progression defined as a composite of renal replacement therapy initiation or 50% decline in estimated glomerular filtration rate (eGFR) from baseline.

RESULTS

Of the 811 cases, 677 (83.5%) had polar vasculosis. In multivariate logistic regression analysis, subendothelial widening of the glomerular basement membrane, glomerulomegaly, glomerular class in the Renal Pathology Society classification ≥IIb, vascular lesions, age, eGFR, and hemoglobin A1c were positively associated with polar vasculosis, whereas interstitial fibrosis and tubular atrophy (IFTA) was negatively associated with polar vasculosis. During a median follow-up of 5.2 years, progression of DKD occurred in 322 of 677 (7.4 events/100 person-years) and 79 of 134 (11.4 events/100 person-years) cases with and without polar vasculosis, respectively. Kaplan-Meier analysis showed that polar vasculosis was associated with lower cumulative incidences of DKD progression. Multivariate Cox regression analyses showed that polar vasculosis was associated with a lower risk of DKD progression, regardless of eGFR or proteinuria subgroups. These associations between polar vasculosis and better kidney outcome were unchanged considering all-cause mortality before DKD progression as a competing event.

CONCLUSIONS

This study showed that polar vasculosis of DKD was associated with less advanced IFTA and a better kidney outcome in type 2 diabetes with proteinuria.

Serum oxalate concentration is associated with coronary artery calcification and cardiovascular events in Japanese dialysis patients

Coronary artery calcification (CAC) is associated with cardiovascular disease (CVD). CAC might contain calcium oxalate, and a high serum oxalate (SOx) concentration is associated with cardiovascular mortality in dialysis patients. We assessed the associations between SOx and CAC or CVD events in Japanese hemodialysis patients. This cross-sectional and retrospective cohort study was done in 2011. Seventy-seven hemodialysis patients' Agatston CAC score was measured, and serum samples were collected. SOx concentrations were measured in 2021 by using frozen samples. Also, new-onset CVD events in 2011-2021 were retrospectively recorded. The association between SOx concentration and CAC score ≥ 1000, and new-onset CVD events were examined. Median SOx concentration and CAC score were 266.9 (229.5-318.5) µmol/L and 912.5 (123.7-2944), respectively. CAC score ≥ 1000 was associated with SOx [adjusted odds ratio (OR) 1.01, 95% confidence interval (CI), 1.00-1.02]. The number of new-onset CVD events was significantly higher in patients with SOx ≥ median value [hazard ratio (HR) 2.71, 95% CI 1.26-6.16]. By Cox proportional hazard models, new-onset CVD events was associated with SOx ≥ median value (adjusted HR 2.10, 95% CI 0.90-4.91). SOx was associated with CAC score ≥ 1000 and new-onset CVD events in Japanese hemodialysis patients.

Chapter 2:indications and dosing of anticancer drug therapy in patients with impaired kidney function, from clinical practice guidelines for the management of kidney injury during anticancer drug therapy 2022

This comprehensive review discusses the dosing strategies of cancer treatment drugs for patients with impaired kidney function, specifically those with chronic kidney disease (CKD), undergoing hemodialysis, and kidney transplant recipients. CKD patients often necessitate dose adjustments of chemotherapeutic agents, e.g., platinum preparations, pyrimidine fluoride antimetabolites, antifolate agents, molecularly targeted agents, and bone-modifying agents, to prevent drug accumulation and toxicity due to diminished renal clearance of the administered drugs and their metabolites. In hemodialysis patients, factors such as drug removal from hemodialysis and altered pharmacokinetics demand careful optimization of anticancer drug therapy, including dose adjustment and timing of administration. While free cisplatin is removed by hemodialysis, most of the tissue- and protein-bound cisplatin remains in the body and rebound cisplatin elevations are observed after hemodialysis. It is not recommended hemodialysis for drug removal, regardless of timing. Kidney transplant patients encounter unique challenges in cancer treatment, as maintaining the balance between reduction of immunosuppression, switching to mTOR inhibitors, and considering potential drug interactions with chemotherapeutic agents and immunosuppressants are crucial for preventing graft rejection and achieving optimal oncologic outcomes. The review underscores the importance of personalized, patient-centric approaches to anticancer drug therapy in patients with impaired kidney function.

Chapter 3: Management of kidney injury caused by cancer drug therapy, from clinical practice guidelines for the management of kidney injury during anticancer drug therapy 2022

Cisplatin should be administered with diuretics and Magnesium supplementation under adequate hydration to avoid renal impairment. Patients should be evaluated for eGFR (estimated glomerular filtration rate) during the treatment with pemetrexed, as kidney injury has been reported. Pemetrexed should be administered with caution in patients with a CCr (creatinine clearance) < 45 mL/min. Mesna is used to prevent hemorrhagic cystitis in patients receiving ifosfamide. Febuxostat is effective in avoiding hyperuricemia induced by TLS (tumor lysis syndrome). Preventative rasburicase is recommended in high-risk cases of TLS. Thrombotic microangiopathy could be triggered by anticancer drugs and there is no evidence of efficacy of plasma exchange therapy. When proteinuria occurs during treatment with anti-angiogenic agents or multi-kinase inhibitors, dose reductions or interruptions based on grading should be considered. Grade 3 proteinuria and renal dysfunction require urgent intervention, including drug interruption or withdrawal, and referral to a nephrologist should be considered. The first-line drugs used for blood pressure elevation due to anti-angiogenic agents are ACE (angiotensin-converting enzyme) inhibitors and ARBs (angiotensin receptor blockers). The protein binding of drugs and their pharmacokinetics are considerably altered in patients with hypoalbuminemia. The clearance of rituximab is increased in patients with proteinuria, and the correlation with urinary IgG suggests similar pharmacokinetic changes when using other antibody drugs. AIN (acute interstitial nephritis) is the most common cause of ICI (immune checkpoint inhibitor)-related kidney injury that is often treated with steroids. The need for renal biopsy in patients with kidney injury that occurs during treatment with ICI remains controversial.

Public support for patients with intractable diseases in Japan: impact on clinical indicators from nationwide registries in patients with autosomal dominant polycystic kidney disease

BACKGROUND

Clinical practice guidelines recommend antihypertensive and tolvaptan therapies for patients with autosomal dominant polycystic kidney disease (ADPKD) in Japan. However, tolvaptan therapy may pose an economic burden. The Japanese Ministry of Health, Labour and Welfare supports patients with intractable diseases. This study aimed to confirm the impact of the intractable disease system in Japan on the clinical treatment of ADPKD.

METHODS

We analyzed the data of 3768 patients with ADPKD having a medical subsidy certificate from the Japanese Ministry of Health, Labour and Welfare in 2015-2016. The following quality indicators were use: the adherence rate to the 2014 clinical practice guideline for polycystic kidney disease (prescription rates of antihypertensive agents and tolvaptan in this cohort) and the number of Japanese patients with ADPKD nationwide started on renal replacement therapy in 2014 and 2020.

RESULTS

Compared with new applications from 2015 to 2016, the prescription rates of antihypertensives and tolvaptan for the indicated patients at the 2017 renewal application increased by 2.0% (odds ratio = 1.41, p = 0.008) and 47.4% (odds ratio = 10.1, p > 0.001), respectively. These quality indicators improved with antihypertensive treatment, especially in patients with chronic kidney disease stages 1-2 (odds ratio = 1.79, p = 0.013) and in those aged < 50 years (odds ratio = 1.70, p = 0.003). The number of patients with ADPKD who were started on renal replacement therapy in Japan decreased from 999 in 2014 to 884 in 2020 in the nationwide database (odds ratio = 0.83, p < 0.001).

CONCLUSIONS

The Japanese public intractable disease support system contributes to improvement of ADPKD treatment.

Chapter 4: CKD treatment in cancer survivors, from Clinical Practice Guidelines for the Management of Kidney Injury During Anticancer Drug Therapy 2022

Chronic kidney disease (CKD) is one of the most disabling disorders with significant comorbidity and mortality. Incidence and prevalence of CKD in cancer survivors are remarkably high in both adults and pediatric patients. The reasons for this high incidence/prevalence are multifold but kidney damage by cancer itself and cancer treatment (pharmacotherapy/surgery/radiation) are the main reasons. Since cancer survivors commonly have significant comorbidities, risk of cancer recurrence, limited physical function or life expectancy, special attentions should be paid when considering the treatment of CKD and its complications. Especially, shared decision-making should be considered when selecting the renal replacement therapies with as much information/facts/evidence as possible.

Chapter 1: Evaluation of kidney function in patients undergoing anticancer drug therapy, from clinical practice guidelines for the management of kidney injury during anticancer drug therapy 2022

The prevalence of CKD may be higher in patients with cancer than in those without due to the addition of cancer-specific risk factors to those already present for CKD. In this review, we describe the evaluation of kidney function in patients undergoing anticancer drug therapy. When anticancer drug therapy is administered, kidney function is evaluated to (1) set the dose of renally excretable drugs, (2) detect kidney disease associated with the cancer and its treatment, and (3) obtain baseline values for long-term monitoring. Owing to some requirements for use in clinical practice, a GFR estimation method such as the Cockcroft-Gault, MDRD, CKD-EPI, and the Japanese Society of Nephrology's GFR estimation formula has been developed that is simple, inexpensive, and provides rapid results. However, an important clinical question is whether they can be used as a method of GFR evaluation in patients with cancer. When designing a drug dosing regimen in consideration of kidney function, it is important to make a comprehensive judgment, recognizing that there are limitations regardless of which estimation formula is used or if GFR is directly measured. Although CTCAEs are commonly used as criteria for evaluating kidney disease-related adverse events that occur during anticancer drug therapy, a specialized approach using KDIGO criteria or other criteria is required when nephrologists intervene in treatment. Each drug is associated with the different disorders related to the kidney. And various risk factors for kidney disease associated with each anticancer drug therapy.

Adolescent-onset TAFRO Syndrome with Malignant Nephrosclerosis-like Lesions

A 16-year-old Japanese girl developed a fever, thrombocytopenia, and renal dysfunction. Treatment was started with steroids, but cervical lymphadenopathy and ascites developed. A lymph node biopsy indicated TAFRO syndrome. The patient's renal function deteriorated, and dialysis was started. Refractory hypertension and subsequent encephalopathy developed. Treatment was started with an anti-IL-6 receptor antibody and an anti-CD20 monoclonal antibody. A kidney biopsy showed malignant nephrosclerosis-like microangiopathy and glomerular collapse due to narrowing of the small arteries. The majority of TAFRO syndrome cases are adult-onset, with glomerular microangiopathy. To our knowledge, this is the first report of adolescent-onset TAFRO syndrome presenting with malignant nephrosclerosis-like lesions associated with hypertension.

Apolipoprotein E-associated Lipoprotein Glomerulo-tubulopathy

A 32-year-old man was admitted for the evaluation of proteinuria (5.69 g/day). A light microscopic examination showed markedly dilated glomerular capillary loops with vacuolated areas in many glomeruli, and vacuolated areas were seen on peritubular capillaries in the tubulointerstitium. When electron microscopy specimens prepared by pre-fixation with glutaraldehyde and post-fixation with osmium tetroxide were used for oil red staining, the deposition was confirmed on the affected areas. A genetic analysis of apoE showed that the lipoprotein glomerulopathy was due to apoE-Sendai (Arg145Pro, p.R163P) heterozygosity, which was found in not only the patient but also his mother and twin brother.

Glomerular hyperfiltration and hypertrophy: an evaluation of maximum values in pathological indicators to discriminate "diseased" from "normal"

The success of sodium-glucose cotransporter 2 inhibitors and bariatric surgery in patients with chronic kidney disease has highlighted the importance of glomerular hyperfiltration and hypertrophy in the progression of kidney disease. Sustained glomerular hyperfiltration and hypertrophy can lead to glomerular injury and progressive kidney damage. This article explores the relationship between obesity and chronic kidney disease, focusing on the roles of glomerular hyperfiltration and hypertrophy as hallmarks of obesity-related kidney disease. The pathological mechanisms underlying this association include adipose tissue inflammation, dyslipidemia, insulin resistance, chronic systemic inflammation, oxidative stress, and overactivation of the sympathetic nervous system, as well as the renin-angiotensin aldosterone system. This article explains how glomerular hyperfiltration results from increased renal blood flow and intraglomerular hypertension, inducing mechanical stress on the filtration barrier and post-filtration structures. Injured glomeruli increase in size before sclerosing and collapsing. Therefore, using extreme values, such as the maximal glomerular diameter, could improve the understanding of the data distribution and allow for better kidney failure predictions. This review provides important insights into the mechanisms underlying glomerular hyperfiltration and hypertrophy and highlights the need for further research using glomerular size, including maximum glomerular profile, calculated using needle biopsy specimens.

Can Takayasu Arteritis Cause Hydronephrosis?

A 74-year-old woman was admitted because of malaise and a low-grade fever. Her C-reactive protein level was 0.96 mg/dL. Computed tomography (CT) revealed diffuse uniform thickening of the arterial wall from the abdominal aorta to the common iliac artery and right hydronephrosis. ¹⁸F-fluordesoxyglucose positron emission tomography-CT showed an accumulation in the same area. These findings suggested Takayasu arteritis and retroperitoneal fibrosis as differential diagnoses. Takayasu arteritis is characterized by thickening of the arterial walls, and retroperitoneal fibrosis is characterized by membranous lesions covering the outer surface of the arterial walls. Thus, Takayasu arteritis was deemed the most likely diagnosis. Steroid treatment was effective.

Crescentic Glomerulonephritis with Fibrinoid Vasculitis after Administration of Influenza Vaccine

A 66-year-old man was admitted to our hospital because of a low-grade fever and arthralgia. The symptoms started on the third day after influenza vaccine administration and persisted for two months. Serum creatinine was 1.0 mg/dL; C-reactive protein, 16.1 mg/dL; and myeloperoxidase antineutrophil cytoplasmic antibodies (MPO-ANCA), 4,170 IU/mL. A kidney biopsy showed crescentic glomerulonephritis with fibrinoid necrosis of small arteries. Microscopic polyangiitis was diagnosed. After five months of steroid pulse therapy and rituximab administration, the patient entered remission. There have been very few reports of this condition after influenza vaccine administration.

Successful Discontinuation of Glucocorticoid Treatment after Administration of a Calcineurin Inhibitor for Nephrotic Syndrome in a Patient with Lupus Nephritis

Systemic lupus erythematosus was diagnosed in a patient at 43 years old. When proteinuria recurred at 57 years old, the first kidney biopsy was performed, and class IV-G (A) +V lupus nephritis was diagnosed. The prednisolone dose was increased to 40 mg/day, and cyclosporine A was introduced. After 1 year, proteinuria had decreased to 0.1 g/day. Prednisolone was discontinued three years later, and cyclosporine A was continued. Thereafter, proteinuria did not reoccur. At 67 years old, a second kidney biopsy showed complete remission of lupus nephritis. Cyclosporine A enabled permanent discontinuation of glucocorticoids in a patient with lupus nephritis.

A Half-Century Dialysis Survivor: Clinical and Autopsy Findings

A man in his 20s initiated intermittent peritoneal dialysis in the late 1960s. He subsequently transitioned to hemodialysis and survived for more than 50 years, spanning low-flux and high-flux hemodialysis eras. He underwent surgery for cervical and lumbar spinal canal stenosis after 30 and 35 years, respectively, and both surgeries revealed similar degrees of severe amyloid deposition. At autopsy, significant improvement was seen in lumbar amyloid deposition. During the previous 25 years, serum β2 microglobulin levels had decreased from 40 mg/L and been maintained at 20 mg/L. This case indicates that advances in dialysis therapy aimed at lowering β2 microglobulin concentrations have reduced highly deposited amyloid.

Citric acid-based bicarbonate dialysate attenuates aortic arch calcification in maintenance hemodialysis patients: a retrospective observational study

BACKGROUND

Progression of aortic calcification is associated with all-cause and cardiovascular mortality in hemodialysis patients. Blood calciprotein particle (CPP) levels are associated with coronary artery calcification and were reported to be inhibited when using citric acid-based bicarbonate dialysate (CD). Therefore, this study aimed to examine the effect of CD on the progression of the aortic arch calcification score (AoACS) and blood CPP levels in hemodialysis patients.

METHODS

A 12-month retrospective observational study of 262 hemodialysis patients was conducted. AoACS was evaluated by calculating the number of calcifications in 16 segments of the aortic arch on chest X-ray (minimum score is 0; maximum score is 16 points). The patients were divided into the following groups according to their baseline AoACS: grade 0, AoACS = 0 points; grade 1, AoACS 1-4 points; grade 2, AoACS 5-8 points; grade 3, AoACS 9 points or higher. Patients on bisphosphonates or warfarin or with AoACS grade 3 were excluded. Progression, defined as ΔAoACS (12-month score - baseline score) > 0 points, was compared between the CD and acetic acid-based bicarbonate dialysate (AD) groups before and after adjusting the background using propensity score matching.

RESULTS

The AoACS progression rate was significantly lower in the CD group than in the AD group (before matching: P = 0.020, after matching: P = 0.002). Multivariate logistic regression analysis showed that CD was significantly associated with AoACS progression (odds ratio 0.52, 95% confidence interval 0.29‒0.92, P = 0.025).

CONCLUSION

CD may slow the progression of vascular calcification in hemodialysis patients.

Acute renal intracystic hemorrhage in patients with autosomal dominant polycystic kidney disease

BACKGROUND

Renal cyst bleeding is a frequent problem in patients with autosomal dominant polycystic kidney disease (ADPKD). However, information is still limited on its frequency, causative factors, and effects on enlargement of polycystic kidneys in ADPKD.

METHODS

We investigated the total volume of acute renal intracystic hemorrhage and its association with total kidney volume (TKV) in a large series of patients with ADPKD on dialysis, referred for renal transcatheter arterial embolization. All patients had undergone CT scan and MRI scan before the procedure. We evaluated factors potentially associated with acute renal intracystic hemorrhage. The association between the  volume of acute renal intracystic hemorrhage and the potential predisposing and associated factors was analysed by univariable and multivariable regressions.  RESULTS: We enrolled 199 patients who underwent renal transcatheter arterial embolization from 2014 to 2018 (107 men, 92 women; mean age 59.1 ± 8.6 years). The median volume of acute renal intracystic hemorrhage was 97.3 ml (interquartile range 36.6-261.7 ml). Multivariable analysis revealed that body weight, kidney stones, systolic blood pressure, and total volume of acute renal intracystic hemorrhage were significantly associated with TKV; age, body mass index, smoking, renal cyst infection, serum alkaline phosphatase, and TKV were significantly associated with the volume of acute renal intracystic hemorrhage ; and sex, age, dialysis vintage, TKV, and total volume of acute renal intracystic hemorrhage were significantly associated with the number of microcoils required to achieve renal  transcatheter arterial embolization. Total volume of acute renal intracystic hemorrhage was significantly associated with TKV (r = 0.15, p = 0.0325) and was greater in younger patients (r= - 0.32, p < 0.0001). Total volume of acute renal intracystic hemorrhage was also correlated with the number of microcoils required for renal transcatheter arterial embolization (r = 0.23, p = 0.0012).

CONCLUSION

Acute renal intracystic hemorrhage is frequent among ADPKD patients on dialysis, and total volume of acute renal intracystic hemorrhage significantly associated with  TKV. Total volume of acute renal intracystic hemorrhage  was greater in younger patients with higher renal artery luminal size. These results suggest that renal cyst bleeding and renal artery blood flow may synergistically accelerate the enlargement of polycystic kidneys in ADPKD patients on dialysis.

A case of malignant nephrosclerosis occurring with serum renin in the normal range

A 37-year-old Japanese man was admitted to our hospital for evaluation of severe hypertension and visual impairment. His serum creatinine was 4.16 mg/dL. Plasma renin activity was normal (2.7 ng/mL/h), but plasma aldosterone concentration was elevated (27.2 ng/dL). A kidney biopsy showed concentric subendothelial edematous thickening of the arterioles (onion skin pattern) with luminal narrowing or obstruction, and malignant nephrosclerosis was diagnosed. Antihypertensive therapies, including an angiotensin II receptor blocker and spironolactone, were administered and effectively preserved kidney function and normalized blood pressure. This case indicates that hyperaldosteronemia in the presence of normal renin levels might also cause malignant hypertension.

Development of an enterocutaneous fistula from an intestinal perforation in a patient with autosomal dominant polycystic kidney disease

We herein report a case of enterocutaneous fistula in a patient with autosomal dominant polycystic kidney disease (ADPKD). A 37-year-old Japanese man was admitted to our hospital. Three months prior to transfer to our hospital, he developed intense flank pain with gross hematuria. His serum creatinine had decreased to 7.8 mg/dL and hemodialysis was started, but gross hematuria persisted and he developed hypotension. Upon admission, plain chest radiography did not reveal any free air, but computed tomography (CT) showed generalized ventral subcutaneous air from the head to the lower extremities and enlarged kidneys. Enterography showed leakage of contrast medium from the descending colon into the subcutaneous area. C-reactive protein was 23.1 mg/dL. A colostomy was placed in the transverse colon proximal to the perforation, and systemic subcutaneous drainage was performed. The fever subsequently resolved, and the C-reactive protein test became negative. Three months later, renal artery embolization was performed, and 12 months thereafter, CT showed a marked decrease in kidney size. We assume that a markedly enlarged kidney leaded to intestinal perforation, which developed into an enterocutaneous fistula. Consequently, intestinal fluid leaked into the subcutaneous cavity of the abdominal wall and spread systemically, resulting in extensive subcutaneous abscesses.

Kidney Histology Findings in a Patient with Autosomal Dominant Tubulointerstitial Kidney Disease Subtype Hepatocyte Nuclear Factor 1β

We evaluated kidney histology in a 43-year-old woman with autosomal dominant tubulointerstitial kidney disease subtype hepatocyte nuclear factor 1β. Magnetic resonance imaging showed multiple cysts in the renal medullary area, and computed tomography showed hypoplasia of the pancreatic body and tail. A kidney biopsy showed thinning of the cortex, size reduction of glomerular tuft area, proximal tubule clustering, fibrosis around the tubules, loss of peritubular capillaries, and multilayered epithelial cells of cortical collecting ducts; this last finding was consistent with so-called medullary dysplasia specific to congenital disease, in which the renal pelvic epithelial cells enter the collecting duct.

Long-term effectiveness of a primary care practice facilitation program for chronic kidney disease management: an extended follow-up of a cluster-randomized FROM-J study

BACKGROUND

Practice facilitation program by multidisciplinary care for primary care physicians (PCPs) is expected to improve chronic kidney disease (CKD) outcomes, but there is no clear evidence of its long-term effectiveness. We have previously performed a cluster-randomized controlled trial for 3.5 years (the Frontier of Renal Outcome Modifications in Japan (FROM-J) study) with two arms-group A without the program and group B with the program. We aimed to assess the long-term effectiveness of the practice facilitation program on CKD outcomes via an extended 10-year follow-up of the FROM-J study.

METHODS

We enrolled patients who were in the FROM-J study. The primary composite endpoint comprised cardiovascular disease (CVD), renal replacement therapy initiation and a 50% decrease in the estimated glomerular filtration rate (eGFR). The secondary endpoints were survival rate, eGFR decline rate and collaboration rate between PCPs and nephrologists.

RESULTS

The occurrence of the primary composite endpoint tended to be lower in group B (group A: 27.1% versus group B: 22.1%, P = 0.051). Furthermore, CVD incidence was remarkably lower in group B (group A: 10.5% versus group B: 6.4%, P = 0.001). Although both mortality and the rate of eGFR decline were identical between both groups, the eGFR decline rate was significantly better in group B than in group A only in patients with stage G3a at enrollment (group A: 2.35 ± 3.87 mL/min/1.73 m2/year versus group B: 1.68 ± 2.98 mL/min/1.73 m2/year, P = 0.02). The collaboration rate was higher in group B.

CONCLUSIONS

The CKD practice facilitation program for PCPs reliably decreases CVD events and may reduce the progression of cases to end-stage kidney disease.

Changes in Kidney and Liver Volumes in Patients With Autosomal Dominant Polycystic Kidney Disease Before and After Dialysis Initiation

Objective

To examine the changes in total kidney volume (TKV) and total liver volume (TLV) before and after dialysis initiation in patients with autosomal dominant polycystic kidney disease.

Patients and Methods

This was a retrospective, single-center cohort study to investigate the changes in TKV and TLV before and after dialysis initiation, along with influencing factors, using linear mixed models. We enrolled 95 patients with autosomal dominant polycystic kidney disease (85 receiving hemodialysis [HD] and 10 receiving peritoneal dialysis [PD]) who began receiving dialysis at Toranomon Hospital from January 1, 2008, to December 31, 2020.

Results

The least squares mean TKV ratio (TKV at each time point/TKV at dialysis initiation) was 63.8% (95% confidence interval [CI], 54.7%-72.9%) at 6 years before dialysis initiation and 95.5% (95% CI, 82.9%-108.2%) at 6 years after dialysis initiation (P<.001). A multivariate linear mixed model analysis revealed that dialysis style (HD or PD) had the strongest effect on changes in TKV (P=.002). The least squares mean TLV ratio was 98.2% (95% CI, 88.4%-108.0%) at 6 years before dialysis initiation and 95.7% (95% CI, 85.2%-106.2%) at 6 years after dialysis initiation (P=.01). Although PD did not have significant effects on changes in TLV (P=.27), the changes in TLV were greater in patients on PD than in those on HD.

Conclusion

The TKV increased until dialysis initiation and generally decreased after dialysis initiation. The TLV continued to increase even after dialysis initiation, however, changes in the TLV significantly decreased after dialysis initiation. The increases in TKV and TLV were greater in patients on PD than in those on HD.

A Bone Histomorphometric Analysis of Hypophosphatasia-related Osteoporosis after Teriparatide Treatment

A 79-year-old man was admitted with a compression fracture of the first lumbar vertebra. His alkaline phosphatase (ALP) level was 35 IU/L, and his dual energy X-ray absorptiometry T score was -3.7 standard deviations, indicating osteoporosis. A genetic analysis showed a mutation of the alkaline phosphatase biomineralization-associated gene encoding tissue-nonspecific alkaline phosphatase. Hypophosphatasia-related osteoporosis was diagnosed. Alendronate, teriparatide, and minodronate were administered in that order. The ALP level increased during teriparatide use. A bone biopsy performed after three years of teriparatide treatment showed that cancellous bone was adynamic. In cortical bone, tetracycline double-labeling indicates enhanced bone formation. Teriparatide may thus be a viable treatment option even in patients with hypophosphatasia.

Visceral fat and attribute-based medicine in chronic kidney disease

Visceral adipose tissue plays a central role in obesity and metabolic syndrome and is an independent risk factor for both cardiovascular and metabolic disorders. Increased visceral adipose tissue promotes adipokine dysregulation and insulin resistance, leading to several health issues, including systemic inflammation, oxidative stress, and activation of the renin-angiotensin-aldosterone system. Moreover, an increase in adipose tissue directly and indirectly affects the kidneys by increasing renal sodium reabsorption, causing glomerular hyperfiltration and hypertrophy, which leads to increased proteinuria and kidney fibrosis/dysfunction. Although the interest in the adverse effects of obesity on renal diseases has grown exponentially in recent years, the relationship between obesity and renal prognosis remains controversial. This may be attributed to the long clinical course of obesity, numerous obesity-related metabolic complications, and patients' attributes. Multiple individual attributes influencing the pathophysiology of fat accumulation make it difficult to understand obesity. In such cases, it may be effective to elucidate the pathophysiology by conducting research tailored to individual attributes from the perspective of attribute-based medicine/personalized medicine. We consider the appropriate use of clinical indicators necessary, according to attributes such as chronic kidney disease stage, level of visceral adipose tissue accumulation, age, and sex. Selecting treatments and clinical indicators based on individual attributes will allow for advancements in the clinical management of patients with obesity and chronic kidney disease. In the clinical setting of obesity-related nephropathy, it is first necessary to accumulate attribute-based studies resulting from the accurate evaluation of visceral fat accumulation to establish evidence for promoting personalized medicine.

Pregnancy Complications and Impact on Kidney Allograft After Kidney Transplantation in IgA Nephropathy

Pregnancy in kidney transplantation (KT) recipients has been challenging because of the high risk of maternal, fetal, and renal complications. Although patients with immunoglobulin A nephropathy (IgAN)-chronic kidney disease (CKD) are at a high risk for hypertension in pregnancy (HIP), the maternal risk in KT recipients with IgAN as the etiology remains unclear. We retrospectively reviewed the medical records of pregnant KT recipients who delivered at our hospital. The incidence of maternal and fetal complications and the impact on kidney allografts between the group with IgAN as the primary kidney disease and the group with other primary diseases were compared. The analysis included 73 pregnancies in 64 KT recipients. The IgAN group had a higher incidence of HIP than the non-IgAN group (69% vs. 40%, p = 0.02). IgAN as primary kidney disease and interval from transplantation to conception were associated with HIP (OR 3.33 [1.11-9.92], p = 0.03, OR 0.83 [0.72-0.96], p < 0.01, respectively). The 20-year graft survival or prevention of CKD stage 5 in group with IgAN was lower than that in the group with other primary disease (p < 0.01). KT recipients should be informed of the risk of HIP and possibility of long-term worsening of postpartum renal function.

A Case of Rapidly Progressive Diabetic Nephropathy Induced by Osimertinib

The number of patients with diabetic nephropathy is increasing worldwide and it is important to understand the underlying pathological mechanisms of the disease. In early stage diabetic nephropathy, the hyperglycemic environment leads to vascular endothelial cell damage, resulting in overexpression of vascular endothelial growth factor (VEGF) in podocytes and renal pathology of glomerular hypertrophy, glomerular basement membrane thickening, and mesangial hyperplasia. In diabetic nephropathy, renal thrombotic microangiopathy (TMA) develops and the nephropathy progressively worsens in some cases of severe glomerular podocyte damage. Further, receptor tyrosine kinase inhibitors (RTKIs) may suppress VEGF secretion via VEGF receptor-2 tyrosine kinase inhibition in podocytes, which results in renal TMA and rapid deterioration of diabetic nephropathy. Osimertinib, a third-generation irreversible epidermal growth factor receptor (EGFR)-TKI, is approved as a first-line treatment agent for metastatic or locally advanced EGFR mutation-positive non-small cell lung cancer. We encountered a case of a patient with diabetic nephropathy with lung adenocarcinoma treated with osimertinib, whose condition deteriorated from early nephropathy to end-stage renal disease in approximately 4 months. The patient had early diabetic nephropathy, but the use of a RTKI suppressed VEGF expression in podocytes, resulting in the induction of renal TMA and the development of rapidly progressive diabetic nephropathy.

Endothelial Damage-dominant Nephritis Related to IgA Vasculitis after 11 Years' Use of Infliximab for Rheumatoid Arthritis

A 43-year-old Japanese woman with rheumatoid arthritis treated by infliximab and methotrexate for 11 years was admitted for proteinuria and purpura. A kidney biopsy revealed endothelial damage-dominant nephritis with IgA deposition. Infliximab and methotrexate were discontinued, and tocilizumab was started; however, proteinuria persisted. Therefore, tocilizumab was discontinued, and oral prednisolone and methylprednisolone pulse therapy were administered. After 6 months, urinary protein was less than 0.1 g/day, and purpura subsided. To our knowledge, this is the first case of endothelial damage-dominant nephritis related to IgA vasculitis involving the skin and kidney after long-term use of infliximab and methotrexate.

Synergistic deterioration of prognosis associated with decreased grip strength and hyporesponse to erythropoiesis-stimulating agents in patients undergoing hemodialysis

Introduction

We examined the combined effect of erythropoietin (EPO) hyporesponsiveness and low handgrip strength (HGS) on the prognosis of patients undergoing hemodialysis (HD).

Methods

We recruited patients with chronic kidney disease (CKD) Stage 5, who were undergoing HD at our dialysis clinic between January 2015 and March 2015 (n = 182). Patients of ≥20 years of age and who had been undergoing HD for ≧3 months at enrollment were eligible for inclusion. Seven patients treated with epoetin-β pegol were excluded. First, the erythropoietin resistance index (ERI) and HGS were measured. The patients were stratified by the ERI of 9.44 (U/kg/week/g/dL), and by the HGS of 28 kg for men and 18 kg for women. We then observed death and cardiovascular disease (CVD), composite endpoint (deaths or CVD) for a median of 2 years.

Results

A total of 175 patients (male, n = 122; female, n = 53; age, 34–92 years) were included in the analysis. During the observation period of 24 months, 57 events (14 deaths and 43 CVD) were observed. High ERI and low HGS were associated with a high incidence of endpoints compared to low ERI and high HGS. Among the four groups classified by ERI and HGS values, the highest risk group was the high ERI/low HGS group (HR: 4.20 95% CI 2.12–8.33).

Conclusions

EPO hyporesponsiveness combined with low HGS were found to be significant predictors of a poor outcome, and the synergistic effects of the two factors had stronger predictive ability than either single factor.

Microbiome of infected cysts, feces and saliva in patients with autosomal dominant polycystic kidney disease

Cyst infection is a frequent and serious complication of autosomal dominant polycystic kidney disease (ADPKD). Hematogenous spread via bacterial translocation in the intestine is considered to be the main cause, so intestinal flora may be involved. However, the exact role of the intestinal flora in cyst infection in ADPKD is unknown. We report a 66-year-old woman and a 56-year-old man with ADPKD who had severe hepatic cyst infection. We analyzed the microbiome of infected cyst content, feces, and saliva in these two patients. The microbiome of patient 1 showed various bacteria in an infected cyst, whereas that of patient 2 showed only one bacterium. In both patients, the composition of the microbiome of the cyst content was quite different from those of feces and saliva, and the main bacteria in the infected cyst content represented a small proportion of those in feces and saliva. Lactobacilli were not almost detected in the infected cyst content though some lactobacilli are endemic in the gastrointestinal tract and the saliva. The association between bacteria in cysts and those in feces or saliva remains uncertain, and further research on this topic is needed.

Glomerular Microangiopathy with Cellular Crescent-like Formation and Endotheliopathy Due to Ramucirumab Treatment for Metastatic Sigmoid Colon Cancer

We encountered a 77-year-old Japanese man who presented with nephrotic-range proteinuria 20 days after receiving ramucirumab treatment for metastatic sigmoid colon cancer. A kidney biopsy showed two characteristic histological findings. The first finding was podocyte injury with cellular crescent-like formation, although focal segmental glomerulosclerosis (FSGS) (collapsing variant) according to the Columbia classification may have been a more appropriate name for this injury, as hypertrophy and hyperplasia of epithelial cells, presumably resulting from podocyte injury, were seen between Bowman's capsule and the glomerular basement membrane (GBM); these changes appeared to be due to the collapse of the GBM rather than to GBM destruction with fibrinoid necrosis. The second finding was endotheliopathy characterized by prominent mesangial interposition via enlargement of the mesangial matrix with mesangiolysis. Proteinuria and renal dysfunction subsided after discontinuation of ramucirumab. Bevacizumab has been reported to induce glomerular microangiopathy with endothelial damage and swelling six months after treatment, but in this case, ramucirumab may have induced focal segmental glomerulosclerosis (FSGS) collapsing variant and glomerular microangiopathy with endotheliopathy via mesangial damage within 1 month. We believe that the damage to the glomerular podocyte and endothelial cells via mesangial damage secondary to ramucirumab in our patient was a different type of glomerular microangiopathy than the endothelial cell damage with enlargement of the subendothelial space caused by bevacizumab.

Machine learning for morbid glomerular hypertrophy

A practical research method integrating data-driven machine learning with conventional model-driven statistics is sought after in medicine. Although glomerular hypertrophy (or a large renal corpuscle) on renal biopsy has pathophysiological implications, it is often misdiagnosed as adaptive/compensatory hypertrophy. Using a generative machine learning method, we aimed to explore the factors associated with a maximal glomerular diameter of ≥ 242.3 μm. Using the frequency-of-usage variable ranking in generative models, we defined the machine learning scores with symbolic regression via genetic programming (SR via GP). We compared important variables selected by SR with those selected by a point-biserial correlation coefficient using multivariable logistic and linear regressions to validate discriminatory ability, goodness-of-fit, and collinearity. Body mass index, complement component C3, serum total protein, arteriolosclerosis, C-reactive protein, and the Oxford E1 score were ranked among the top 10 variables with high machine learning scores using SR via GP, while the estimated glomerular filtration rate was ranked 46 among the 60 variables. In multivariable analyses, the R² value was higher (0.61 vs. 0.45), and the corrected Akaike Information Criterion value was lower (402.7 vs. 417.2) with variables selected with SR than those selected with point-biserial r. There were two variables with variance inflation factors higher than 5 in those using point-biserial r and none in SR. Data-driven machine learning models may be useful in identifying significant and insignificant correlated factors. Our method may be generalized to other medical research due to the procedural simplicity of using top-ranked variables selected by machine learning.

Cystic Kidney Diseases That Require a Differential Diagnosis from Autosomal Dominant Polycystic Kidney Disease (ADPKD)

Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary cystic kidney disease, with patients often having a positive family history that is characterized by a similar phenotype. However, in atypical cases, particularly those in which family history is unclear, a differential diagnosis between ADPKD and other cystic kidney diseases is important. When diagnosing ADPKD, cystic kidney diseases that can easily be excluded using clinical information include: multiple simple renal cysts, acquired cystic kidney disease (ACKD), multilocular renal cyst/multilocular cystic nephroma/polycystic nephroma, multicystic kidney/multicystic dysplastic kidney (MCDK), and unilateral renal cystic disease (URCD). However, there are other cystic kidney diseases that usually require genetic testing, or another means of supplementing clinical information to enable a differential diagnosis of ADPKD. These include autosomal recessive polycystic kidney disease (ARPKD), autosomal dominant tubulointerstitial kidney disease (ADTKD), nephronophthisis (NPH), oral-facial-digital (OFD) syndrome type 1, and neoplastic cystic kidney disease, such as tuberous sclerosis (TSC) and Von Hippel-Lindau (VHL) syndrome. To help physicians evaluate cystic kidney diseases, this article provides a review of cystic kidney diseases for which a differential diagnosis is required for ADPKD.

[Management of Chronic Kidney Disease in Cancer Survivors]

Chronic kidney disease(CKD)associated with cancer and its treatment affects life after cancer treatment. There is inconclusive opinion on whether CKD treatment in survivors after cancer treatment needs special care differently than in the general population with CKD. Several topics were discussed by nephrologists, urologists and medical oncologists, pediatricians, pharmaceutical specialists, and others based on the results of a literature search, and the consensus was documented in the "Clinical Practice Guidelines for the Management for Kidney Injury During Anticancer Drug Therapy, 2022". The prevalence of CKD among adult cancer survivors is reported to be 4-7%. The characteristics include(1)elderly and physically impaired patients(, 2)a high risk of cancer recurrence, and(3)frequently cancer treatment-related CKD. Although there are no cancer survivor-specific indications or contraindications in the selection of renal replacement therapy, renal transplantation is often preferred in pediatric cancer survivors. It was determined that it is not appropriate to recommend or not recommend the administration of erythropoietin stimulating agents for renal anemia in cancer survivors based on a systematic review and discussion between panelists. When used in individual cases, its application should be well examined and consideration should be given to avoiding high hemoglobin level and to monitoring for cancer development.

Glycated albumin to glycated hemoglobin ratio and mortality in diabetic patients on dialysis: a new association

Hemoglobin A1c (A1c) and glycated albumin (GA) are two blood glycated proteins commonly used to monitor glycemic control in dialysis patients with diabetes. However, little is known about the association between the GA/A1c ratio and mortality in these populations. Here, we examine these associations using a nationwide cohort.

We enrolled 28 994 dialysis patients with diabetes who met our inclusion criteria (female, 32.9%; mean age, 67.4 ± 11.6 years; mean dialysis duration, 6.3 ± 5.8 years). After dividing the patients into groups based on GA/A1c quantiles and adjusting for 18 potential confounders, adjusted hazard ratios and 95% confidence limits were calculated for 3-year mortality and cause-specific mortalities. Additionally, propensity score matching analyses were used to compare mortalities between the low and high GA/A1c groups.

After adjusting for possible confounders, significantly increased mortality was found in patients with GA/A1c ratios of 3.6–4.0 (HR 1.21 (1.10–1.34)) or higher (HR 1.43 (1.30–1.58)) than in those with GA/A1c ratios of 3.0–3.3. The risks of infectious and cardiovascular death were higher in these patients regardless of their nutritional status. In the propensity score matching analyses, significantly increased mortality was consistently found in those with a higher ratio (≥3.3) (HR 1.23 (1.14–1.33)) than in those with a lower ratio.

The GA/A1c ratio was significantly associated with 3-year mortality, especially infectious and cardiovascular mortality, in dialysis patients with diabetes. This ratio may be a promising new clinical indicator of survival in these patients, independent of their current glycemic control and nutritional markers.

Thrombotic Microangiopathy, Podocytopathy, and Damage to the Renal Tubules with Severe Proteinuria and Acute Renal Dysfunction Induced by Lenvatinib

Lenvatinib, a tyrosine kinase inhibitor (TKI), is a stronger inhibitor of vascular endothelial growth factor receptor, fibroblast growth factor receptors 1 to 4, and platelet-derived growth factor receptor (PDGFR) than other TKIs. We herein report a 77-year-old Japanese woman who received the minimum dose of lenvatinib for treatment of hepatocellular carcinoma. Within one month of starting treatment, she developed severe proteinuria, hypertension, and renal dysfunction. A kidney biopsy showed drug-induced thrombotic microangiopathy, podocytopathy, and polar vasculosis. We also observed damage to the renal tubules, where PDGFR is located. To our knowledge, this is the first report of lenvatinib-induced damage to the renal tubules.

Vincristine, Doxorubicin, and Dexamethasone Induction before Autologous Stem Cell Transplantation in Patients with AL Amyloidosis: A Retrospective Comparison with Frontline Stem Cell Transplantation

Objective High-dose melphalan and autologous stem cell transplantation (ASCT) therapy for AL amyloidosis are now associated with reduced mortality based on the application of strict criteria. However, there is no long-term evidence concerning the performance of induction therapy with newer agents, such as bortezomib or daratumumab. Concerns regarding long-term relapse despite treatment with ASCT exist, and missing the opportunity to perform ASCT might occur if induction proves to not be efficacious and cardiac amyloidosis progression deprives the patients of a chance to receive ASCT. We herein report good amyloid control by vincristine, doxorubicin, and dexamethasone (VAD) induction therapy and argue the importance of induction therapy before ASCT. Methods We compared patients who underwent VAD induction and ASCT (VAD+ASCT) with patients who underwent frontline ASCT in our hospital. Patients A total of 26 patients with histologically proven AL amyloidosis were included (18 in the VAD+ASCT group and 8 in the frontline ASCT). Results In the VAD+ASCT group, the 10-year overall survival and renal response rates were 82% and 43%, respectively. The renal response rate at two years in the VAD+ASCT group was significantly better than that in the frontline ASCT group. Although there was no significant difference in the survival rates between the two groups, the time to next treatment or death was significantly better in the VAD+ASCT group than in the the frontline ASCT group. Acute kidney injury was the most frequent reason for failure to receive two courses of VAD, and early mortality was mainly due to gastrointestinal complications. Conclusion Considering that only those who underwent 2 courses of VAD experienced a 10-year renal response, induction therapy was deemed to be directly related to the long-term control of AL amyloidosis.

Activity of daily life dependency predicts the risk of mortality in patients with COVID-19 undergoing hemodialysis: a retrospective analysis of a single center with nosocomial outbreak

Background

We experienced a nosocomial outbreak of coronavirus disease 2019 (COVID-19) from November 2020 to February 2021, during the third wave of the pandemic in Japan.

Methods

We retrospectively assessed the characteristics and data of 20 inpatients undergoing hemodialysis who were hospitalized for treatment of diseases other than COVID-19 during the COVID-19 nosocomial outbreak (“inpatient,” IP), and of 10 outpatients undergoing hemodialysis who were hospitalized for the care of COVID-19 under outpatient visits (“outpatient,” OP).

Results

Eleven patients in the IP group (55%) and one in the OP group (10%) died. Kaplan–Meier analysis showed that the IP group died more rapidly than the OP group (p = 0.02). Multivariate analysis among all hemodialysis patients showed that the IP group was not at risk of mortality independently; however, the activity of daily life (ADL) dependency was found to be an independent factor in increasing the risk of mortality (hazard ratio: 7.618).

Conclusion

Our findings show that the nosocomial infected group has a worse prognosis, although it is not an independent predictor for the risk of mortality. ADL dependency could predict the risk of mortality in all hemodialysis patients with COVID-19 during the third wave pandemic in Japan.