B-type (brain) natriuretic peptide and pruritus in hemodialysis patients.

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 (ß=2.0, t=2.4, P=0.03), calcium (ß=4.4, t=5.2, P<0.0001), and ß2-microglobulin (ß=2.0, t=3.0, P=0.007), while it was eased by age (ß=-2.2, t=-3.2, P=0.0004). Nocturnal pruritus was severe in nondiabetic patients (ß=1.7, t=3.8, P=0.0005) and weakened by the total iron binding capacity (ß=-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.

Fluctuation of serum C3 levels reflects disease activity and metabolic background in patients with IgA nephropathy.

BACKGROUND: We focused on the fluctuations of serum C3 levels throughout the clinical course of patients and investigated the relationship between these fluctuations and clinical findings. METHODS: IgA nephropathy patients (n = 122) were enrolled in the present study. Serum C3 and other clinical markers were compared at the time of renal biopsy and at last follow-up (6.67 ± 2.07 years). Patients were divided into 3 groups based on serum C3 levels: Group I with first C3 levels below the mean -1 SD, which turned into an increase at last observation; group II with first C3 levels more than the mean +1 SD, which turned into a decrease at last observation; and group III, with first C3 levels more than the mean +1 SD, which turned into an increase at last observation. First and last levels of clinical markers were compared among the 3 groups. RESULTS: Serum C3 levels of the patients whose renal symptoms, including hematuria, proteinuria and estimated glomerular filtration rate (eGFR), were improved, were significantly increased at last observation (p<0.05, p<0.01, p<0.01, respectively). Age, total cholesterol and triglyceride levels in group III were significantly higher than those in group I. Group II showed a significant reduction of urinary protein. Groups I and II maintained renal function, but group III showed a significant deterioration of renal function. CONCLUSIONS: The levels and fluctuations of serum C3 might reflect the disease activity and metabolic alteration in patients with IgA nephropathy.

Campylobacter bacteremia in hemodialysis patients by eating raw meat - the importance of sanitary education.

In 2011, simultaneous, widespread outbreaks of food poisoning by contaminated enterohemorrhagic Escherichia coli in beef, which killed four and hospitalized more than 30 people, occurred in Japan. While the press was widely reporting this disaster, two maintenance hemodialysis patients were suffering from Campylobacter bacteremia by eating undercooked meat. One patient was infected with C. upsaliensis and the other with C. fetus. Although these patients could be successfully treated, they led us to consider the characteristics of C. upsaliensis and C. fetus as opportunistic pathogens, as well as changes in dietary behaviors and food markets. Moreover, they emphasized the need for hemodialysis patients to be not only educated in that they should restrict potassium, phosphate and water intake, but also that they should take care of food sanitation.

Effects of acetate-free citrate dialysate on glycoxidation and lipid peroxidation products in hemodialysis patients.

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.

One-year results of an open-label study on antiproteinuric effect of benidipine in elderly patients with chronic kidney disease.

BACKGROUND: The long-term antiproteinuric effects of benidipine, a calcium channel blocker (CCB), have not been evaluated in detail in hypertensive patients with chronic kidney disease (CKD). METHODS: Benidipine (4 mg/day) was administered to previously untreated hypertensive patients with CKD, or hypertensive patients with CKD not achieving target blood pressure (BP) despite taking an angiotensin II receptor blocker (ARB). The patients were followed up for 1 year. If target BP was not achieved by 2 weeks after the start of benidipine treatment, the dosage was increased to 8 mg/day. The urinary protein to creatinine (UP/cre) ratio was evaluated before and after benidipine treatment. RESULTS: This study evaluated 65 hypertensive patients with CKD. BP (systolic/diastolic) decreased from 154 ± 19 / 91 ± 12 mm Hg before treatment to 134 ± 16 / 78 ± 10 mm Hg at 1 year after treatment (p<0.001). The UP/cre ratio decreased significantly from 2.21 ± 2.47 g/g creatinine (g/g cre) before treatment to 1.43 ± 2.21 g/g cre after treatment (p<0.001). In both the untreated and ARB-treated groups, the BP and UP/cre ratio decreased significantly at 1 year after treatment. The percentage change in the UP/cre ratio was significantly greater in patients aged 65 years or older than in those less than 65 years (79.1% vs. 48.7%, p=0.038). CONCLUSIONS: Benidipine treatment reduced the UP/cre ratio in hypertensive patients with CKD, and the percentage decrease of the UP/cre ratio was greater in elderly patients, suggesting that benidipine may have more potent antiproteinuric effects in elderly hypertensive patients with CKD.

Usefulness of a body composition analyzer, InBody 2.0, in chronic hemodialysis patients.

The objective of the present study was to investigate whether InBody 2.0 might be useful in measuring the dry weight of chronic hemodialysis (HD) patients. Thirty-five HD patients (22 males and 13 females; mean age 62.6 +/- 14.0 years; mean HD duration 101.0 +/- 118.06 months) were examined. Multifrequency bioelectric impedance analysis was used to estimate the ratio of extracellular water (ECW) to total body water (TBW). The body resistance was measured at frequencies ranging from 1 kHz to 1 MHz. The impedance index was determined at a low frequency (5 kHz) and correlated closely with ECW, using sodium bromide dilution as standard comparison. The levels of serum albumin, prealbumin, total cholesterol (TC), triglycerides (TG), transferrin, and human atrial natriuretic peptide (hANP) were measured by routine methods in our hospital. The ECW/TBW ratio was significantly associated with the levels of hANP (p < 0.05). However, no associations between the levels of serum albumin, TC, TG, or transferrin and the ECW/TBW were observed. It appears that the body composition analyzer, InBody 2.0, may be useful for estimating the dry weight in chronic HD patients.

Relationship between renal anemia and prognostic stages of IgA nephropathy.

In 2002, the Joint Committee of the Special Study Group on Progressive Glomerular Diseases, Ministry of Health, Labor and Welfare of Japan newly revised the clinical guidelines for IgA nephropathy (Sakai et al.: Jpn J Nephrol 37:417-421, 1995; Tomino and Sakai: Clin Exp Nephrol, 7, 93-97, 2003). The prognostic stages were classified into four groups: the good prognosis group (Group I), relatively good prognosis group (Group II), relatively poor prognosis group (Group III), and poor prognosis group (Group IV). The relationship between the levels of Hb, Ht, and RBC in peripheral blood and the renal prognostic stages was determined in 62 patients with IgA nephropathy in the present study. The mean levels of Hb, Ht, and RBC were significantly lower in Group IV than in Group I (P<0.05). However, there were no significant changes in the levels of serum creatinine (s-Cr) or creatinine clearance (CCr) among these four groups. It appears that the levels of Hb, Ht, and RBC in peripheral blood may be important clinical parameters for the evaluation of prognostic stages in patients with IgA nephropathy.

A case of primary immunoglobulin light chain amyloidosis with a delayed appearance of Bence Jones protein in urine.

We report here a case of a 58-year-old man who had nephrotic syndrome and immunoglobulin light chain (AL) amyloidosis. This patient underwent a renal biopsy to confirm the diagnosis. Treatment with permanganate before Congo red staining showed systemic secondary amyloidosis (AA) fibrils, which were sensitive to permanganate oxidation. Although this patient was initially diagnosed as having AA amyloidosis, he did not have any chronic inflammatory disease and/or malignancy. The level of amyloid A protein (7.9 microg/mL) in sera was within the normal range (0-8.0 microg/mL). Therefore, we performed an immunostaining of the precursor protein (amino terminus of constant region: kappa and lambda light chains, and AA protein) using duodenal biopsy specimens for a precise diagnosis. Immunostaining was positive for the amino terminus of constant region of the lambda light chain, and negative for the amino terminus of constant region of the kappa light chain and AA protein. No plasma cell proliferation in the bone marrow was observed. We finally diagnosed this patient as having primary AL amyloidosis. It appears that a pathological diagnosis must be performed by immunostaining the precursor proteins with the permanganate digestion technique in tissue of patients with amyloidosis. There were no abnormalities in serum and urine immunoelectrophoresis at the time of renal biopsy in this patient. During the follow-up period, after discharge, Bence Jones protein appeared in the urine, but not in the serum. It is necessary to observe patients with primary AL amyloidosis carefully to determine if they their condition will progress to multiple myeloma.