No abstract

Hereditary renal hypouricemia is characterized by hypouricemia with hyper-uric acid clearance due to a defect in renal tubular transport. Patients with hereditary renal hypouricemia have a higher risk of exercise-induced acute kidney injury (EAKI) and reduced kidney function. Although the best preventive measure is avoiding exercise, there are many kinds of jobs that require occupational exercise. A 27-year-old male police officer suffered from stage 3 AKI after performing a 20-m multistage shuttle run test. His mother had previously been diagnosed as having renal hypouricemia at another facility. The patient had reported having hypouricemia during a health check at a previous police station, but his serum uric acid concentration was within the normal range at our hospital. After treatment, he recovered from EAKI and exhibited low serum uric acid and hyper-uric acid clearance. Since the patient desired to continue his career requiring strenuous exercise, it was difficult to establish a preventive plan against the recurrence of EAKI. Patients with hereditary renal hypouricemia who must undergo strenuous occupational anaerobic exercise are at higher risk of developing EAKI than other workers. The risks of EAKI among patients with hypouricemia should be considered when undergoing physical occupational training.

Background/Aims: Previous studies have shown the presence of high levels of glycoxidation and lipid peroxidation products in association with atherosclerosis in patients with end-stage kidney disease. Acetates are commonly used buffer for correcting metabolic acidosis in hemodialysis (HD) patients. Since the toxic effects of acetates are well established, acetate-free citrate dialysate (AFD) has become available in Japan. The objective of the present study was to evaluate the suppressive effects of AFD on oxidative stress in maintenance HD patients by measuring plasma pentosidine and malondialdehyde-modified low-density lipoprotein (MDA-LDL) levels as markers for glycoxidation and lipid peroxidation products. Methods: Plasma pentosidine, MDA-LDL and other laboratory parameters were examined on maintenance HD at the Juntendo University Hospital before and after switching to AFD. Results: MDA-LDL levels divided by LDL cholesterol were significantly lower than those before switching to AFD. Furthermore, levels of plasma pentosidine were lower than those before switching to AFD. Stepwise multiple regression analysis revealed that the percent change of the calcium-phosphorus product in the nondiabetic group and that of phosphorus in the diabetic group were predictive variables for the percent change of MDA-LDL/LDL, whereas the percent change of log high-sensitive C-reactive protein and that of systolic blood pressure in the nondiabetic group and that of diastolic blood pressure in the diabetic group were predictive variables for the percent change of plasma pentosidine. Conclusions: It appears that AFD decreases glycoxidation and lipid peroxidation products when compared with acid citrate dextrose in HD patients. The reduction of oxidative stress by AFD during HD may have possible beneficial effects on atherosclerosis through calcium-phosphorus metabolism and blood pressure.

Introduction and objective:While pruritus is a common complication in hemodialysis patients, the pathophysiological mechanisms remain obscure. Recently, B-type (brain) natriuretic peptide (BNP) has been defined as an itch-selective neuropeptide in pruriceptive neurons in mice, and higher serum levels of BNP are frequently observed in hemodialysis patients. The objective of the present study was to evaluate the role of serum BNP in pruritus in patients undergoing hemodialysis. Patients and methods:The current cross-sectional study was performed on 43 patients undergoing maintenance hemodialysis. A visual analog scale (VAS) measuring the general severity of pruritus (values from 0 to 10, with higher values indicating more severe pruritus) in daytime and at night was self-reported by patients. Each patient's background and laboratory tests, including serum BNP in the post-hemodialysis period, were collected. The correlation between VAS and clinical parameters was evaluated. Results: Both daytime and nighttime VAS scores in diabetic patients were significantly less than those in nondiabetic patients. Multiple regression analysis revealed that pruritus in daytime was worsened by serum BNP (β=2.0, t=2.4, P=0.03), calcium (β=4.4, t=5.2, P,0.0001), and β 2 -microglobulin (β=2.0, t=3.0, P=0.007), while it was eased by age (β=-2.2, t=-3.2, P=0.0004). Nocturnal pruritus was severe in nondiabetic patients (β=1.7, t=3.8, P=0.0005) and weakened by the total iron binding capacity (β=-2.9, t=-3.1, P=0.004). Conclusion: It is suggested that a higher level of serum BNP increases the pruritus of hemodialysis patients in daytime and that diabetic patients are less sensitive to itch, especially at nighttime.

Background: Although deep hypothermic circulatory arrest (DHCA) is a useful option to protect the central nervous system during aortic arch operations, the influence of simultaneous renal ischemia remains controversial. Patients and Methods: This is a retrospective observational study. Sixty-three patients who underwent thoracic aortic surgery with DHCA and 24 patients who underwent cardiac surgery without DHCA were included in this study. The mean age, preoperative serum creatinine (Cr) level, preoperative estimated glomerular filtration rate (eGFR), peak serum Cr level up to 48 hrs post-operative, elevation rate of Cr compared to the preoperative serum Cr, urine volume rate up to 48 hrs post-operative and AKI staging using the KDIGO criteria were estimated for each patient. Clinical parameters for 3 months after the operation and the 3-month post-operative mortality rate were assessed. Mean values indicating kidney function or distribution of the AKI stages were compared between patients with and without DHCA. Patients with DHCA were further divided according to the duration of ischemia to compare the values for the kidney function of each group, distribution of AKI stages and mortality. Results:The parameters indicating AKI of the patients with DHCA were significantly more severe than those without DHCA. Patients who had undergone an ischemic state for more than 40 min revealed significantly higher peak serum Cr, elevation rate of serum Cr, less urine volume up to 48 hrs post-operative compared with those without DHCA. Distribution of the AKI stages was related to the duration of ischemia. The 3-month post-operative mortality of the patients with DHCA was significantly higher than those without DHCA. Limitations: This study had limitations such as its retrospective design and small number patients, and the data will be required confirmation with other prospective studies. Conclusion: DHCA is closely related to AKI up to 48 hrs post-operative and death during the 3 months following surgery.