Effect of vitamin E-bonded dialyzer on eosinophilia in haemodialysis patients.

BACKGROUND: Eosinophilia in haemodialysis patients probably results from allergy to haemodialysis-related materials, including dialyzer membranes. We examined the effects of vitamin E-bonded dialyzers on eosinophil counts in haemodialysis patients. METHODS: We enrolled seven patients who were on regular haemodialysis and had sustained eosinophilia. White blood cell, eosinophil, CD4- and CD8-positive lymphocyte counts, and serum interleukin-5 (IL-5) and IgE levels were determined before, 2 and 4 weeks after switching to vitamin E-bonded dialyzers. RESULTS: Eosinophil and CD4-positive lymphocyte counts and serum IL-5 were significantly (P = 0.003, 0.003 and 0.031, respectively) decreased after switching to vitamin E-bonded dialyzers. CD8-positive lymphocyte counts and serum IgE levels were unaltered. Crossover tests in two cases reproduced the higher eosinophilia within 4 weeks after returning to the original non-vitamin E-bonded dialyzer. CONCLUSION: Vitamin E-bonded dialyzers may ameliorate eosinophilia through a mechanism mediated by a decrease in IL-5 secretion by CD4-positive lymphocytes.

A low-protein diet concomitant with high calorie intake preserves renal function and structure in diabetic OLETF rats.

BACKGROUND: Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a spontaneous type 2 diabetes model, were used to clarify whether and how a low-protein diet prevents progressive diabetic nephropathy, in terms of functional and structural parameters. METHODS: A low-protein diet (LPD) with 11% protein content, was compared to the normal 24% protein diet (NPD) without keeping isocaloric conditions. Daily food intake, body weight, and blood and urine chemistry were serially measured in rats from 10 through 60 weeks of age, and renal clearance studies and histological evaluations were performed at 40 and 60 weeks of age. RESULTS: Daily calorie intake was higher in the OLETF rats fed on the LPD than in those fed on the NPD throughout the experiment. Due to this hyperphagia, fasting blood glucose and hemoglobin (Hb)A1c were dramatically increased in the LPD-fed OLETF rats at 30 weeks and thereafter, whereas urinary protein excretion was decreased by more than half after 26 weeks in the LPD group. Plasma concentrations of total cholesterol and triglyceride were decreased in the LPD-fed OLETF rats at 40 and 60 weeks. Inulin clearance in the LPD group was higher only at 60 weeks of age. The glomerular sclerosis index (GSI) and tubulointerstitial index (TII) were preserved in the LPD group. The LPD induced a decrease in tubulointerstitial macrophage infiltration as compared with the NPD at both 40 and 60 weeks of age, but glomerular macrophage infiltration was not alleviated. CONCLUSIONS: A low-protein diet, despite the worsening hyperglycemia caused by hyperphagia, not only reduced proteinuria but also ameliorated hyperlipidemia in OLETF rats, thereby preserving renal function and structure in diabetic nephropathy, probably via a macrophage-mediated mechanism.

Gene expression of vitamin D hydroxylase and megalin in the remnant kidney of nephrectomized rats.

BACKGROUND: Regulation of vitamin D hydroxylase genes in the early stage of chronic renal failure is not fully understood. Using nephrectomized rats, we examined changes in mRNA levels of CYP27B1 (25-hydroxyvitamin D3-1 alpha-hydroxylase), CYP24 (25-hydroxyvitamin D3-24-hydroxylase), and vitamin D receptor in relation to megalin, recently found to participate in renal vitamin D metabolism. METHODS: A rat model of moderate renal failure was induced by 3/4 nephrectomy. Plasma parameters, including vitamin D metabolite concentrations, were measured at weeks 2, 4 and 8, and poly(A)+ RNA extracted from the remnant kidneys was subjected to Northern blot hybridization. RESULTS: Plasma creatinine concentration at week 2 was 0.40 +/- 0.02 mg/dL in the sham-operated and 0.93 +/- 0.15 mg/dL in the nephrectomized rats, and both values remained constant up to week 8. Plasma concentrations of 25(OH)D3, 1 alpha,25(OH)2D3, and 24,25(OH)2D3 were unchanged between nephrectomized and sham-operated rats at week 8. Intact parathyroid hormone (PTH) increased at week 8 in nephrectomized rats. CYP27B1 mRNA in nephrectomized rats did not vary at week 2, but increased approximately two- and four-fold at weeks 4 and 8, respectively, compared to the sham-operated rats. CYP24 and megalin mRNAs, on the other hand, began to decline as early as at week 2 in nephrectomized rats and kept decreasing throughout the experiment. The expression of vitamin D receptor was modestly but significantly decreased only at week 8. CONCLUSION: Coordinated and reciprocal alterations of the increase in CYP27B1 mRNA and the decrease in CYP24 mRNA may play a pivotal role in maintaining the plasma level of 1 alpha,25(OH)2D3 in the face of reduced nephron mass and/or megalin expression.

[A case of fulminant acute poststreptococcal glomerulonephritis showing mesangiolysis and crescent formation preceded by erysipelas].

A 66-year-old man with erysipelas was admitted with complaints of oliguria and massive proteinuria/hematuria. He was diagnosed as having acute poststreptococcal glomerulonephritis(APSGN) due to erysipelas infected by group A streptococcus pyogenes. On admission, his white cell count increased to 31,000, and CRP was 27.3 mg/dl. Serum urea nitrogen and creatinine were increased to 90.1 mg/dl and 4.5 mg/dl, respectively. He had diabetes mellitus(HbA1c 7.9%) and liver dysfunction(total bilirubin 3.5 mg/dl, AST 76 IU, ALT 41 IU) caused by alcoholic liver cirrhosis. Hypocomplementemia was found in addition to ASO 216 U/ml and ASK 10,240 x. After antibiotics treatment was initiated, inflammation of the erysipelas began to improve. Disseminated intravascular coagulation syndrome, probably due to sepsis, occurred on the 5th hospital day. He died of gastrointestinal bleeding on the 18th hospital day. Renal autopsy revealed 37% formation of fibrocellular crescents, and marked mesangiolysis was noted by light microscopy. Granular deposition of C3 and IgG was seen along the capillary walls on immunofluorescence study. Intramembranous deposits were scattered on electron microscopy. This case illustrates a fulminant type of APSGN, which was in part attributed to the presence of diabetes and alcoholic liver cirrhosis. Histological findings of crescent formation and marked mesangiolysis may account for the fulminant clinical course.