Development and validation of a machine learning model to predict time to renal replacement therapy in patients with chronic kidney disease.

BACKGROUND: Predicting time to renal replacement therapy (RRT) is important in patients at high risk for end-stage kidney disease. We developed and validated machine learning models for predicting the time to RRT and compared its accuracy with conventional prediction methods that uses the rate of estimated glomerular filtration rate (eGFR) decline. METHODS: Data of adult chronic kidney disease (CKD) patients who underwent hemodialysis at Oita University Hospital from April 2016 to March 2021 were extracted from electronic medical records (N = 135). A new machine learning predictor was compared with the established prediction method that uses the eGFR decline rate and the accuracy of the prediction models was determined using the coefficient of determination (R2). The data were preprocessed and split into training and validation datasets. We created multiple machine learning models using the training data and evaluated their accuracy using validation data. Furthermore, we predicted the time to RRT using a conventional prediction method that uses the eGFR decline rate for patients who had measured eGFR three or more times in two years and evaluated its accuracy. RESULTS: The least absolute shrinkage and selection operator regression model exhibited moderate accuracy with an R2 of 0.60. By contrast, the conventional prediction method was found to be extremely low with an R2 of -17.1. CONCLUSIONS: The significance of this study is that it shows that machine learning can predict time to RRT moderately well with continuous values from data at a single time point. This approach outperforms the conventional prediction method that uses eGFR time series data and presents new avenues for CKD treatment.

Nephrotic Syndrome Associated with Buerger's Disease.

We herein report a 43-year-old woman with Buerger's disease who presented with nephrotic syndrome, renal dysfunction, and mild hypertension. A kidney biopsy revealed focal segmental glomerulosclerosis (FSGS), but there were no findings associated with frequent secondary FSGS or a history of long-term hypertension. A small focal renal infarction was seen on 99mTc-dimercaptosuccinic acid renal scintigraphy, suggesting that FSGS was due to renal microinfarction associated with Buerger's disease. After the commencement of angiotensin-converting enzyme inhibitor therapy, the hypertension immediately improved, along with significant attenuation of proteinuria. Renal ischemia by vasoconstriction of the glomerular efferent arterioles in association with Buerger's disease may result in glomerular hyperfiltration followed by FSGS.

[Carfilzomib-induced renal impairment with albuminuria in a patient with relapsed/refractory multiple myeloma].

A 70-year-old woman was diagnosed with multiple myeloma in 2014. She achieved complete remission (CR) after bortezomib, cyclophosphamide, dexamethasone (VCD) therapy and lenalidomide, dexamethasone (Rd) therapy; however, she relapsed in 2017. Although she achieved second CR by carfilzomib, dexamethasone (Kd) therapy, serum creatinine levels increased with urinary protein after 17 courses of Kd therapy. Urinary protein test revealed albuminuria, whereas M-protein was undetectable. Carfilzomib-induced renal impairment was suspected due to absence of other causes, such as progression of myeloma or autoimmune disease. On discontinuation of Kd therapy, urinary protein decreased rapidly with improvement of serum creatinine levels within a month. Carfilzomib-induced nephrotoxicity is a rare but important adverse event.

Effects of Sleeve Gastrectomy on Blood Pressure and the Renal Renin-Angiotensin System in Rats with Diet-Induced Obesity.

OBJECTIVE: Sleeve gastrectomy (SG) has been reported to decrease blood pressure (BP), although the reason has not been revealed. The present study aimed to establish the reason why SG decreases BP. METHODS: Male Sprague-Dawley rats were subjected to surgical (sham operation or SG) and dietary interventions (fed a normal diet or high-fat diet ad libitum or fed by pair-feeding [PF]). Systolic BP (SBP), urinary sodium excretion, and endocrine parameters were examined 4 weeks after surgery. RESULTS: Both SG and PF rats had reduced body weight compared with SO rats fed normal diet or high-fat diet ad libitum. SG rats exhibited a reduction in SBP compared with PF, which was associated with a reduction in renal renin, angiotensin II, and catechol-O-methyltransferase levels (P < 0.01 for each). SG increased plasma cholecystokinin (CCK) levels compared with PF (P < 0.0001 for each), whereas glucagon-like peptide 1 and peptide YY were not changed in fasting. Exogenous administration of CCK reduced renal catechol-O-methyltransferase (P = 0.0233), renin (P < 0.0001), and angiotensin II (P < 0.0001) levels and SBP (P = 0.0053). CONCLUSIONS: SG reduced SBP, at least in part, through suppression of sympathetic nerve action by elevation of CCK, which was followed by suppression of the intrarenal renin-angiotensin system.

Treatment of metastatic refractory colorectal cancer following regorafenib failure.

At present, there is no set strategy for the treatment of patients with colorectal cancer subsequent to the failure of standard treatment, other than the use of regorafenib (RGR) and TAS-102. The best order in which to use these drugs, and their safety and efficacy in combination with other drugs, are currently under investigation. It has been reported that RGR has a resensitizing effect on tumors that have previously failed to respond to anticancer drugs; this makes it a promising salvage therapy for colorectal cancer. The present report describes the results of a retrospective study on 17 patients with metastatic colorectal cancer who received RGR treatment following the failure of standard therapy. Following RGR failure, 71% of the patients were fit for further anticancer treatment, and these patients survived longer than those who did not receive further treatment. Furthermore, this intervention did not shorten the period of best supportive care. As a considerable number patients were fit for further anticancer therapy after RGR treatment, which resulted in prolonged survival without shortening the period of best supportive care, it may be beneficial for future research to focus on finding the optimal time at which to switch from RGR to further anticancer therapy.

[A case of hemangioma at the left renal papilla of the calix with anemia and gross hematuria].

An 18-year-old man was admitted to our hospital due to gross hematuria and proteinuria after a marathon race. Contrast-enhanced CT showed no remarkable findings. His gross hematuria and proteinuria disappeared with- out treatment. One year later, he was admitted to our hospital due to reburrent gross hematuria and anemia (serum hemoglobin level of 8.0 g/dL). Both contrast-enhanced CT and renal arteriography revealed no remarkable find- ings; however, cystoscopy showed that his hematuria came from the left ureteral orifice. Ureteroscopy revealed hemorrhage from a large hemangioma at the left renal papilla of the calix. He presented with intermittent gross hematuria, proteinuria, and hypocomplimentemia, suggesting the possibility of glomerulonephritis. His gross hematuria and proteinuria improved after laser coagulation was performed.

A randomized controlled trial of Japanese patients with obsessive-compulsive disorder--effectiveness of behavior therapy and fluvoxamine.

BACKGROUND: The aim of this study was to confirm and compare the efficacy of fluvoxamine (the only licensed SSRI for treatment for OCD in Japan) and behavior therapy in treating Japanese patients with OCD. In addition, we investigated predictors of these treatments. METHODS: Thirty-one outpatients meeting the DSM-III-R criteria for OCD without any axis I disorder were randomly assigned to one of three treatment conditions: BT (behavior therapy +/- pill placebo), FLV [autogenic training (a psychological placebo for OCD) +/- fluvoxamine] and control group [autogenic training (psychological placebo) +/- pill placebo] for 12 weeks of treatment. The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and the Clinical Global Impression-Improvement Scale (CGI-I) were administered blindly at baseline and week 4, 8 and 12. RESULTS: Twenty-eight patients completed this study. Patients in the BT and FLV groups showed significantly more improvement than those in the control group in the mean score of total Y-BOCS; moreover, the BT group showed significantly more reduction in total Y-BOCS score at the end of treatment than the FLV group (BT > FLV, p < 0.01). Patients with lower baseline total Y-BOCS, past history of a major depressive episode and absence of cleaning compulsion improved more with fluvoxamine. CONCLUSIONS: We confirmed the effectiveness of behavior therapy and fluvoxamine for Japanese patients with OCD. Behavior therapy improved the condition of OCD patients more than fluvoxamine.