Performance of the New CKD-EPI Creatinine-and Cystatin C-based Glomerular Filtration Rate Estimation Equation in Living Kidney Donor Candidate.

Background: Accurate preoperative evaluation of renal function in living kidney donor candidates (LKDCs) is crucial to prevent kidney failure after nephrectomy. We examined the performance of various estimated glomerular filtration rate (eGFR) equations, including the new chronic kidney disease epidemiology collaboration (CKD-EPI) equation in LKDCs. Methods: We analyzed 752 LKDCs who were assessed for measured GFR by inulin clearance as part of routine pretransplant examination from 2006 to 2020. CKD-EPI2012 from cystatin C (CKD-EPI12cys), CKD-EPI2021 from creatinine (CKD-EPI21cr), CKD-EPI21cr-cys, Japanese modified (JPN) eGFRcr, and JPN eGFRcys were compared in determining the suitability for LKDCs. Results: CKD-EPI12cys had the lowest absolute and relative biases, with higher P30 and P10, followed by JPN eGFRcys, CKD-EPI21cr, and CKD-EPI21cr-cys. The root mean square error was least for CKD-EPI12cys, then JPN eGFRcys, CKD-EPI21cr-cys, CKD-EPI21cr, and JPN eGFRcr. CKD-EPI21cr, CKD-EPI12cys, and CKD-EPI21cr-cys estimated GFR higher, whereas JPN eGFRcr estimated GFR lower. At the threshold of 90 mL/min/1.73 m2, CKD-EPI21cr had the highest percentage of misclassification at 37.37%, whereas JPN eGFRcr had the lowest percentage of misclassification at 6.91%. Using the age-adapted approach, JPN eGFRcr had the lowest percentage of misclassification into overestimation at 7.31%. All eGFR had >5.0%, and CKD-EPI21cr had the highest percentage of misclassification at 21.94%. Conversely, CKD-EPI21cr-cys had the lowest percentage of misclassification into underestimation at 3.19%, both at the threshold of 90 mL/min/1.73 m2 and the age-adapted approach. JPN eGFRcr had the highest percentage at 33.38% and 40.69%, respectively. Conclusions: In evaluating the renal function of Japanese LKDCs, the new CKD-EPI equation had a lower rate of underestimation but a relatively high rate of overestimation. New GFR estimation formulas are needed to be tailored to each ethnic group to enhance the accuracy and reliability of donor selection processes.

MYH9-related disorder with sole presentation of end-stage kidney disease and long-term, recurrence-free living after living donor renal transplantation: a case report.

MYH9-related disorders are a group of autosomal dominant disorders caused by mutations in MYH9, and are characterized by thrombocytopenia, sensorineural hearing loss, cataracts, and renal failure. Here, we report a case of chronic renal failure due to MYH9-related disorder with renal symptoms in a patient who underwent living-donor renal transplantation. The patient was diagnosed with proteinuria during a health checkup at the age of 12 years. Her renal function gradually deteriorated, and hemodialysis was initiated at 34 years of age. No definitive diagnosis of renal disease was made through renal biopsy. At the age of 35, she underwent living-donor renal transplantation from her mother as the donor. Six years after transplantation, her renal function remained stable, and no evidence of recurrent nephritis was found during renal biopsies. The family history revealed that her father, uncle, and younger brother had end-stage kidney disease. Genetic testing revealed a mutation (p.E1653D) related to the MYH9 gene. As her father had a history of renal biopsy and was diagnosed with focal segmental glomerulosclerosis (FSGS), we diagnosed chronic renal failure due to FSGS associated with MYH9 disorder. There were no findings suggestive of hearing loss, cataracts, or thrombocytopenia in the recipient or their family members with renal failure, and no symptoms other than renal failure were noted.

Assessment of Tumor Markers in Renal Transplant Recipients.

Background/Aim: Malignant tumors are diagnosed using various methods, including diagnostic imaging methods. The measurement of tumor markers is commonly used because of its noninvasiveness and convenience. Furthermore, it is known that the excretion and metabolism of some tumor markers are affected by impaired renal function. In the present study, we investigated the effect of improved renal function on pre-and post-transplantation changes in tumor marker levels [carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), carbohydrate antigen 19-9 (CA19-9), and prostate-specific antigen (PSA)] in renal transplant recipients. Patients and Methods: A total of 116 renal transplant recipients, who had not been diagnosed with malignancies between January 2012 and December 2019, were included, and tumor markers were investigated. Results: CEA showed a significant decrease after kidney transplantation, regardless of the dialysis type (3.6→2.6 ng/ml, p<0.001), while other tumor markers showed a significant increase (AFP: 3.6→3.7 ng/ml; CA19-9: 16.2→19.5 U/ml; PSA: 0.95→1.05 ng/ml; all p<0.05). Pre- and postoperative eGFR ratios and postoperative liver function were identified as factors influencing the postoperative CEA and CA19-9 values, while PSA was influenced by the duration of dialysis. No statistically significant factors were found for AFP levels. Conclusion: Caution should be exercised when investigating tumor markers in patients with renal dysfunction, as tumor marker levels may vary depending on the pathophysiology of each patient.

Remarkable Improvement of Diabetic Nephropathy in Transplanted Allograft after Kidney Transplantation.

Although glomerular damage caused by diabetic nephropathy was thought to be irreversible, in recent years, there have been reports on improvement in glomerular damage with strict glycemic control. However, few reports are available on the pathologic course after renal transplantation of donor-derived grafts with findings of diabetic nephropathy. A 53-year-old woman underwent an ABO blood-type compatible living-donor renal transplant. The recipient had no history of diabetes, and fasting blood glucose and hemoglobin A1c levels were both normal. The donor was a 57-year-old male who had received treatment for type 2 diabetes mellitus for 10 years. Transplant renal biopsy performed 1 h after revascularization showed mesangial matrix expansion and arterial hyalinosis due to diabetic nephropathy. The blood glucose level was within the normal range after transplantation. Mesangial matrix expansion and arterial hyalinosis disappeared in allograft biopsy samples 7 years after transplantation. We observed significant improvement in the pathological findings of donor-derived diabetic nephropathy after renal transplantation in the subsequent follow-ups.

Lower Dose of 5 mL of 1% Lidocaine is More Suitable than the Conventional 10 mL for Caudal Block in Transrectal Prostate Biopsy: A Retrospective Cohort Study.

Objectives: In Japan, caudal block with 1% lidocaine is commonly used for transrectal prostate biopsy. Although 10 mL of 1% lidocaine is commonly used, the appropriate dosage of 1% lidocaine has not been studied. Our hospital routinely uses two different doses (5 or 10 mL) of 1% lidocaine for caudal block for transrectal prostate biopsy. Herein, we retrospectively evaluated the efficacy and safety of both doses of 1% lidocaine. Methods: This retrospective study included 869 patients who underwent transrectal prostate biopsy with caudal block at our hospital. The amount of 1% lidocaine was determined by the day of the week on which the biopsy was performed, and the patient voluntarily chose the day of the biopsy, unaware of the dose of 1% lidocaine used on that day. Pain, anal sphincter tonus, cancer diagnosis rate, and early complications were compared. Results: In total, 466 and 403 patients received 5 and 10 mL of 1% lidocaine for a caudal block, respectively. After propensity-score matching for patient characteristics, each group contained 395 patients. The pain score, anal sphincter tonus score, or prostate cancer diagnosis rate were not significantly different between the two groups. However, rectal bleeding was significantly more frequent and severe in the 10-mL than the 5-mL group (p=0.018 and p=0.0036, respectively). The incidence of other complications was not significantly different between the groups. Conclusions: Our results suggest that 5 mL of 1% lidocaine may be more suitable than 10 mL for caudal block during transrectal prostate biopsy.

D-Asparagine is an Ideal Endogenous Molecule for Measuring the Glomerular Filtration Rate.

Introduction: An ideal endogenous molecule for measuring glomerular filtration rate (GFR) is still unknown. However, a rare enantiomer of serine, d-serine, is useful in GFR measurement. This study explored the potential of other d-amino acids for kidney function assessment. Methods: This was a cross-sectional observational study of 207 living kidney transplant donors and recipients, for whom GFR was measured using clearance of inulin (C-in). Associations between levels of d-amino acids and GFR were analyzed using multivariate factor analysis. Fractional excretion (FE), a ratio of the clearance of a substance to C-in as a standard molecule, was calculated to monitor the excretion ratio after glomerular filtration. Dissociation from an ideal FE of 100% was assessed as a bias. Proportional bias against C-in was calculated using Deming regression. Results: Multivariate analysis identified the blood level of d-asparagine to reflect GFR. Means of blood d-asparagine and clearance of d-asparagine (C-d-Asn) were 0.21 µM and 65.0 ml/min per 1.73 m2, respectively. Inulin-based FE (FEin) of d-asparagine was 98.67% (95% confidence interval [CI]: 96.43-100.90%) and less biased than those of known GFR markers, such as FEin of creatinine (147.93 [145.39-150.46]; P < 0.001) and d-serine (84.84 [83.22-86.46]; P < 0.001). A proportional bias of C-d-Asn to C-in was -7.8% (95% CI, -14.5 to -0.6%), which was minor compared to those of clearance of creatinine (-34.5% [-37.9 to -31.0%]) and d-serine (21.2% [13.9-28.9]). Conclusion: D-Asparagine acts similar to inulin in the kidney. Therefore, d-asparagine is an ideal endogenous molecule that can be used for GFR measurement.

A Case Report of a Kidney Transplant Recipient With Organizing Pneumonia After Graft Loss.

We present a case of a 68-year-old male patient who underwent ABO-incompatible living kidney transplantation from his wife because of immunoglobulin A nephropathy 13 years ago. Over time, the patient showed a gradual decline in graft function and required reinitiation of hemodialysis because of fluid overload, which led to his admission to our hospital. An arteriovenous fistula was created, and subsequently, hemodialysis therapy was started. Because he had chronic cytomegalovirus retinopathy and thrombotic microangiopathy due to immunosuppressive therapy at admission, mycophenolate mofetil and tacrolimus were discontinued during hemodialysis initiation. Only low-dose prednisolone was continued. One week later, the patient had a fever, and chest computed tomography revealed bilateral pneumonia, which was not improved by antibiotics. The patient was diagnosed with organized pneumonia. After ruling out opportunistic infection, including pneumocystis pneumonia, increased doses of prednisolone resulted in the remission of organizing pneumonia.

Single-cell transcriptome analysis of a rat model of bilateral renal ischemia-reperfusion injury.

Ischemia-reperfusion injury (IRI) causes massive tissue damage. Renal IRI is the most common type of acute renal injury, and the defects caused by it may progress to chronic kidney disease (CKD). Rodent models of renal IRI, with various patterns, have been used to study the treatment of human kidney injury. A rat model of bilateral IRI, in which the bilateral kidney blood vessels are clamped for 60 min, is widely used, inducing both acute and chronic kidney disease. However, the molecular mechanisms underlying the effects of bilateral IRI on kidney cells have not yet been fully elucidated. This study aimed to perform a whole-transcriptome analysis of the IRI kidney using single-cell RNA sequencing. We found renal parenchymal cells, including those from the proximal tubule, the loop of Henle, and distal tubules, to be damaged by IRI. In addition, we observed significant changes in macrophage population. Our study delineated the detailed cellular and molecular changes that occur in the rat model of bilateral IRI. Collectively, our data and analyses provided a foundation for understanding IRI-related kidney diseases in rat models.

Remitting seronegative symmetrical synovitis with pitting edema syndrome induced by pembrolizumab in patient with urothelial carcinoma.

Introduction: Recent introduction of immuno-oncology drugs such as pembrolizumab has resulted in improved outcomes for urothelial carcinoma patients. However, immune-related adverse events generally show great variance and are often difficult to diagnose and control. Case presentation: An 84-year-old Japanese male with urothelial carcinoma metastasis to the lungs after a laparoscopic left radical nephroureterectomy procedure was treated with pembrolizumab, an immuno-oncology drug, as second-line therapy. At week 6, inflammatory arthralgia involving the hands and shoulder joints, and edema of the hands were presented. The diagnosis was remitting seronegative symmetrical synovitis with pitting edema syndrome. Pembrolizumab was discontinued, and oral corticosteroid therapy was started. Two months later, pembrolizumab treatment was resumed because of a significant improvement in patient condition. Conclusion: Although rare, immune-related adverse events are occasionally encountered during the use of immune-oncology drugs; thus, early diagnosis and appropriate treatment are important.

Rapid deterioration of renal function following coronavirus disease 2019 in a renal transplant recipient.

Introduction: The coronavirus disease 2019 pandemic emerged in December 2019. Renal transplant recipients receiving chronic immunosuppression are considered to be at a high risk of infection. Aside from upper respiratory tract symptoms, coronavirus disease 2019 has also been reported to cause acute kidney injury in 20-50% of infected cases. Case presentation: A 62-year-old male renal transplant recipient presented with high fever, diarrhea, and cough, concurrent with rapid deterioration of graft function. The patient tested positive for coronavirus disease 2019. The pathological findings of the graft biopsy revealed diffuse flattening of tubular epithelial cells and extensive loss of the brush border in proximal tubular cells. Mycophenolate mofetil was discontinued and sotrovimab, remdesivir, intravenous immunoglobulin, and intravenous methylprednisolone were administered, resulting in gradual improvements in clinical symptoms and renal function. Conclusion: We describe a case of a coronavirus disease 2019-infected kidney transplant recipient who developed severe acute kidney injury caused by severe acute tubular necrosis.

[Robot-Assisted Partial Nephrectomy for Renal Cell Carcinoma Complicated by Leriche Syndrome : A Case Report].

A 71-year-old man was referred to our hospital for treatment of a 2 cm-sized right renal mass incidentally found by computed tomography (CT) and was diagnosed with right renal cell carcinoma cT1aN0M0. Contrast-enhanced CT revealed that the aorta was completely occluded below the inferior mesenteric artery origin, and Leriche syndrome was diagnosed. CT angiography showed several collateral arteries along the abdominal wall. A robot-assisted laparoscopic partial nephrectomy was performed to treat renal cell carcinoma. Preoperatively, we marked the collateral arteries using ultrasonography to avoid injury during trocar insertion. We did not observe any decrease in blood flow in the right leg during the operation. The pathological diagnosis was clear cell renal cell carcinoma. Leriche syndrome is a chronic occlusive disease involving the infrarenal aorta and the iliac arteries. Since lower limb blood flow is dependent on collateral circulation, it is important to avoid injuring the collateral arteries during surgery.

[Ectopic Ureterocele of Adult Male with Urination Difficulty : A Case Report].

Ectopic ureteroceles is sometimes noted in children as an incidental finding in antenatal ultrasonography results or because of symptoms related to a urinary tract infection. In contrast, it is rarely noted in adults, with only 18 cases in Japan presented in literature. We report here a 30-year-old adult male with an ectopic ureterocele discovered due to urination difficulty. The patient noted a poor urine stream and macroscopic hematuria after exercise, and over time needed manual compression on the lower abdomen for urination. Computed tomography results revealed a 35 mm right ureterocele containing a 7.0 mm stone. Cystoscopy showed the ureterocele protruding into the prostatic urethra, which was thought to be the cause of urination difficulty. Transurethral resection of the ureterocele and lithotripsy for the stone were performed. The right ureteral orifice was not visualized during the operation. Resection was performed from the bladder neck side so that the ureterocele wall did not interfere with urination and the calculus was crushed with a pneumatic lithotripter (LithoClast®). Urination difficulty was improved following the procedures. Urinary cystourethrography performed two weeks postoperatively confirmed no vesicoureteral reflux. No symptoms of dysuria or fever were noted at a follow-up visit two months after the operation.

Perirenal fat metastasis of prostate cancer.

A 72-year-old male underwent an abdominal CT scan, which revealed a 17-mm nodular incidentaloma in fat tissue in the left perirenal space. Retroperitoneoscopic surgery was performed to remove the tumor and histopathological results revealed a PSA-positive adenocarcinoma, which was diagnosed as a metastatic lesion associated with prostate cancer. PSA was high at 30.083 ng/ml and MRI findings showed extracapsular extension of prostate cancer in the left peripheral zone of the prostate gland. Biopsy results with a Gleason score of 4 + 4 confirmed the diagnosis of prostate cancer. The case was diagnosed as prostate cancer metastasis in perirenal fat tissue.

The gut microbiota associated with high-Gleason prostate cancer.

We have found that intestinal bacteria and their metabolites, short-chain fatty acids (SCFAs), promote cancer growth in prostate cancer (PCa) mouse models. To clarify the association between gut microbiota and PCa in humans, we analyzed the gut microbiota profiles of men with suspected PCa. One hundred and fifty-two Japanese men undergoing prostate biopsies (96 with cancer and 56 without cancer) were included in the study and randomly divided into two cohorts: a discovery cohort (114 samples) and a test cohort (38 samples). The gut microbiota was compared between two groups, a high-risk group (men with Grade group 2 or higher PCa) and a negative + low-risk group (men with negative biopsy or Grade group 1 PCa), using 16S rRNA gene sequencing. The relative abundances of Rikenellaceae, Alistipes, and Lachnospira, all SCFA-producing bacteria, were significantly increased in high-risk group. In receiver operating characteristic curve analysis, the index calculated from the abundance of 18 bacterial genera which were selected by least absolute shrinkage and selection operator regression detected high-risk PCa in the discovery cohort with higher accuracy than the prostate specific antigen test (area under the curve [AUC] = 0.85 vs 0.74). Validation of the index in the test cohort showed similar results (AUC = 0.81 vs 0.67). The specific bacterial taxa were associated with high-risk PCa. The gut microbiota profile could be a novel useful marker for the detection of high-risk PCa and could contribute to the carcinogenesis of PCa.

[A Case of Prostate Adenocarcinoma Metastasis to the Bilateral Breasts].

A 67-year-old male came to our department with complaints of urinary retention and gross hematuria. The prostate specific antigen (PSA) level in the serum was elevated to 69.5 ng/ml. Thus a transperineal prostate biopsy was performed. The patient was diagnosed with prostate cancer, and lung and bone metastases were also revealed. Treatment for metastatic prostate cancer was performed for approximately 5 years with combined androgen blockade therapy followed by enzalutamide, docetaxel, estramustine, Ra-223 dichloride, estradiol, and then enzalutamide reintroduction. Thereafter, the patient presented with bilateral breast nodules and we referred him to our breast surgery department. Breast needle biopsy findings revealed breast metastasis from prostate cancer, that was not primary breast cancer. The patient underwent a bilateral mastectomy.

[Primary Ureteral Small Cell Carcinoma with Multiple Recurrences and Metastases in the Early Postoperative Period : A Case Report].

A 79-year-old woman who presented with right hydronephrosis was referred to our hospital. Abdominal computed tomography (CT) showed a right ureteral tumor (cT3N0M0). Right nephroureterectomy and partial cystectomy were performed. Pathological examination revealed small cell carcinoma (mixed type ; INFb, pT3, ly1, v1, u-rt0, ur0, RM0). Cystoscopy showed intravesical recurrence of the tumor 3 months after the surgery. Transurethral resection was performed, and histopathological examination revealed small cell carcinoma (pT2). We recommended postoperative chemotherapy ; however, the patient and her family refused consent for chemotherapy. Liver and lymph node metastases developed, and the patient died 2 months after the transurethral resection.

[TWO CASES OF FALSE POSITIVE 123I-MIBG SCINTIGRAPHY FINDINGS OF UPTAKE IN ADRENAL TUMORS].

Case 1 was a 71-year-old female who had been examined by her primary care physician for palpitation and hypertension. Urinary hormone test results revealed elevated urine metanephrine at 0.20 mg/day, urine normetanephrine at 0.45 mg/day and urine noradrenalin at 234.9 µg/day. 123I-MIBG scintigraphy showed uptake in the right suprarenal area, thus she was referred to our department because of pheochromocytoma. She underwent a laparoscopic right adrenalectomy and pathological results led to a diagnosis of adrenocortical adenoma. Case 2 was a 70-year-old female who had been examined at our hospital for hypertension. Blood hormone test results revealed elevated noradrenalin at 0.70 ng/ml. 123I-MIBG scintigraphy showed uptake in the left suprarenal area and she was referred to our department because of pheochromocytoma. She underwent a laparoscopic left adrenalectomy, thus pathological results showed no tumor lesion.

[A Case of Pericardial Effusion Induced by Nivolumab for Metastatic Renal Cell Carcinoma].

A 72-year-old female with left renal cell carcinoma and lymphadenopathy had undergone hand-assisted laparoscopic left nephrectomy and dissection of the lymph node (papillary renal cell carcinoma, type 2, pT3a pN2 M1). She had been treated with adjuvant chemotherapy with sunitinib, temsirolimus and pazopanib. However, the patient was started on nivolumab due to disease progression. After receiving 5 cycles of nivolumab, she was admitted to our emergency room for chest discomfort and appetite loss. Since computed tomographic (CT) scan showed pericardial effusion, we performed pericardiocentesis. Cytological examination of the pericardial effusion demonstrated leukocytes and no malignant cells. CT scan two weeks after cardiocentesis showed no recurrent pericardial effusion. She became stable with nivolumab, but the administration of nivolumab was discontinued and she started receiving axitinib.

[Empyema in Left Ureteral Stump Following Bilateral Nephrectomy and Living Renal Transplant-Case Report].

A 34-year-old male came to us with congenital spina bifida, vesicoureteral reflux and scoliosis. He had been on hemodialysis for chronic renal failure caused by reflux nephropathy since the age of 23 years. At the age of 24, he received bilateral nephrectomy and underwent living renal transplantation from his mother. Hemodialysis was started again at the age of 26, because the renal graft was not functioning. At the age of 34, the patient developed a fever that persisted for a few days. He received antibiotic medication from his physician, but since his condition did not improve he was refered to our hospital. A computed tomography scan examination revealed abscess formation in the left retroperitoneum. Magnetic resonance imaging findings also showed the abscess in the left retroperitoneum. The patient was diagnosed with empyema of the residual ureter and underwent a left ureterectomy procedure.