Zeev Katzir

Evidence for tissue iron overload in long-term hemodialysis patients and the impact of withdrawing parenteral iron

Erythropoiesis in long‐term hemodialyzed (LTH) patients is supported by erythropoietin (rHuEpo) and intravenous (IV) iron. This treatment may end up in iron overload (IO) in major organs. We studied such patients for the parameters of IO in the serum and in major organs.

Comparison of hemostatic factors and serum malondialdehyde as predictive factors for cardiovascular disease in hemodialysis patients

Hemodialysis (HD) patients have accelerated cardiovascular morbidity and mortality rates compared with the general population. Identifying the factors that predict major coronary events in this population can direct the focus on prevention. This cross-sectional study compares known and suspected cardiovascular risk factors in HD patients with and without prevalent cardiovascular disease (CVD). In 76 HD patients (prevalent CVD, 44 of 76 patients), serum lipid, lipoprotein, apolipoprotein (Apo), plasma fibrinogen, tissue plasminogen activator (TPA), plasminogen activator inhibitor (PAI-1), and factor VII levels were measured using standard kits. Serum malondialdehyde (MDA; a marker of oxidative stress) was measured using spectrophotometry. Predictor variables were compared using analysis of variance and chi-squared tests, as appropriate. CVD prevalence was modeled using multiple logistic regression analysis, and odds ratios (OR) were calculated. Serum lipid, lipoprotein, Apo, plasma TPA, PAI-1, and factor VII values did not differ significantly from laboratory norms or discriminate for prevalent CVD in HD patients. Plasma fibrinogen levels were significantly elevated in HD patients compared with laboratory norms (369.4 +/- 130.02 v 276.7 +/- 77.7 mg/dL; P < 0.0001) but were not significantly different in HD patients with and without prevalent CVD. Serum MDA levels, both before and after the midweek HD treatment, were significantly elevated in all HD patients compared with laboratory norms (pretreatment, 2.6 +/- 0.8 nmol/mL; posttreatment, 2.1 +/- 0.3 v 0.91 +/- 0.09 nmol/mL; P < 0.01) and were significantly elevated in HD patients with prevalent CVD versus those without (pretreatment, 2.8 +/- 0.6 v 2.4 +/- 0.4 nmol/mL; P < 0.01; posttreatment, 2.3 +/- 0.4 v 1.94 +/- 0.2 nmol/mL; P < 0.01). Only serum MDA levels, both before and after the midweek treatment, contributed to the explanation of variation in CVD prevalence. OR for CVD in the highest versus lowest tertile of pretreatment MDA level was 2.71 (95% confidence interval [CI], 1.42 to 5.19). ORs for CVD in the highest versus lowest tertile of posttreatment MDA level was 3.65 (95% CI, 1.6 to 8.32).

Pamidronate-induced nephrotoxic tubular necrosis--a case report.

Few cases of pamidronate (bisphosphonate class of drugs) nephrotoxicity in humans have been previously reported in the literature. In 7 patients, the pamidronate-related nephrotoxicity was attributed to focal collapsing glomerulosclerosis [Markowitz et al. 2001], and in 1 patient was related to tubulo-interstitial inflammatory nephritis [Van Doom et al. 2001]. We report herein on a 65-year-old Caucasian female patient who presented with acute chronic renal failure due to pamidronate-induced toxic proximal tubular necrosis without immunologic or inflammatory tubulo-interstitial involvement. The acute pattern of renal failure resolved following cessation of pamidronate administration in this patient for osteoporosis; the patient also had a monoclonal gammopathy of unspecific origin (MGUS).

Anti–HIV indeterminate Western blot in dialysis patients: A long-term follow-up

In a group of 520 patients undergoing chronic hemodialysis, 23 (4. 4%) were enzyme immunoassay (EIA) positive for human immunodeficiency virus (HIV) and indeterminate by Western blot (IWB) analysis. The antibodies were mostly directed against p24 and p55 antigens. A comparison between hemodialysis patients with and without IWB showed significant differences between the two groups with respect to number of units of blood transfused, history of renal transplant rejection, and Rh status. No significant differences were observed with respect to ethnic group, nature of renal disease, duration of hemodialysis, associated diseases, and ABO blood group. The HIV IWB phenomenon may represent abnormal immune reactivity as a result of transplantation antigens and/or autoantibody formation. Five-year follow-up of the HIV EIA-positive IWB patients showed that none had seroconverted to HIV-positive status.

Serious complications of routine ritual circumcision in a neonate: Hydro-ureteronephrosis, amputation of glans penis, and hyponatraemia

A 13-day-old infant developed bilateral hydroureteronephrosis, severe hyponatraemia, hyperkalaemia, and acidosis, as a result of urethral damage following circumcision. The hydroureteronephrosis and biochemical abnormalities normalized after resolution of the penile injury.ConclusionInfants with urinary retention following circumcision may develop hydro-ureteronephrosis and electrolyte disturbances. An awareness of the potential dangers of circumcision may help to limit its complications.

C-reactive protein and carotid and femoral intima media thickness: predicting inflammation.

BACKGROUND C-reactive protein (CRP) is a recognized marker of systemic inflammation. Its association with carotid and femoral intima media thickness (surrogate measures of atherosclerosis) may explain excess cardiovascular disease risk in hemodialysis patients. OBJECTIVES To estimate the association between CRP and both carotid and femoral IMT in hemodialysis (HD) patients; to predict CRP in these patients. METHODS The present cross-sectional study is nested in the Sevelamer hydrochloride and ultrasound-measured femoral and carotid intima media thickness progression in end-stage renal disease (SUMMER) clinical trial. Carotid (common, internal, and bifurcation) and femoral arteries were visualized in B-mode ultrasonography. CRP was measured in serum. RESULTS The study cohort included 144 HD patients (39.5% female, mean age 67.8 ± 11.5 years). All measures of both carotid and femoral IMT were significantly positively associated with CRP. Subjects with a history of smoking or coronary revascularization had significantly higher CRP levels, while subjects treated with sevelamer hydrochloride had significantly lower CRP. CRP was significantly positively associated with serum phosphorus, calcium, alkaline phosphatase, and PTH, and significantly inversely associated with HDL and albumin. CONCLUSIONS CRP is significantly positively associated with both femoral and carotid IMT. Treatment with sevelamer hydrochloride is associated with lower CRP in HD patients.

Effect of sevelamer hydrochloride exposure on carotid intima media thickness in hemodialysis patients.

Background: Elevated phosphorus (P) and calcium (Ca)-P product (Ca × P) are associated with vascular calcification and cardiovascular disease (CVD) morbidity and CVD and all-cause mortality. Objectives: This study examined the effect of sevelamer hydrochloride exposure (regardless of calcium carbonate exposure) on carotid and femoral intima media thickness (IMT), reliable surrogate measures of prospective intimal thickening, in end-stage renal disease patients on maintenance hemodialysis. Methods: The present cross-sectional study is nested in the Sevelamer hydrochloride and ultrasound-measured femoral and carotid intima media thickness progression in end-stage renal disease (SUMMER) clinical trial. Carotid and femoral arteries were visualized in B-mode ultrasonography. Log-transformed IMT was compared by sevelamer hydrochloride exposure and modeled using multiple linear regression. Results: Forty-five subjects were exposed to sevelamer hydrochloride and 130 were not. Exposed subjects had significantly lower carotid IMT, an association which persisted in the multiple linear regression model even after controlling for potentially confounding variables including serum Ca, history of CVD and body weight. Exposed subjects had lower low-density lipoprotein cholesterol levels and significantly higher parathyroid hormone, but no differences in P, Ca and Ca × P. Conclusions: Sevelamer hydrochloride was associated with lower carotid IMT. This association may be mediated through reduction in Ca load, low-density lipoprotein cholesterol lowering or some other pleiotropic effect.

CT findings in ten patients with failed renal allografts: comparison with findings in functional grafts.

Our aim is to report the computed tomography (CT) features of the long-term failed renal allograft. Ten patients with failed renal transplants in whom the graft was left in situ underwent CT for various unrelated indications. The majority of the failed grafts showed marked shrinkage and coarse punctate diffuse parenchymal calcifications. Small cysts were seen in four grafts. A long-term failed renal transplant appeared on CT as a small rounded soft tissue mass. The graft was almost always heavily calcified. Lack of awareness of the nature of such a mass may mislead the radiologist in interpreting it as a space-occupying lesion.

Pregnancy in membranous glomerulonephritis: course, treatment and outcome

BACKGROUND The effect and outcome of pregnancy in women with preexisting glomerulonephritis is a controversial issue. CASE We report the clinical course and treatment of a 23-year-old pregnant woman with biopsy-proven membranous glomerulonephritis. When she conceived, the patient had been in stable remission for 1 year. In the 14th week of pregnancy, the patient developed uncontrolled hypertension and nephrotic syndrome. Daily 1 g methylprednisolone intravenous pulses were administered for 3 days, followed by a 4-week course of oral prednisone, 50 mg/day. Clinical improvement and normalization of arterial blood pressure were achieved. Oral prednisone 60 mg was administered on alternate days for another 4 weeks following 3 days of pulse therapy. At the end of treatment (26th gestational week), we observed a decrease of proteinuria (from 10.6-4.8 g/24 h) and rise in serum albumin (from 2.1-2.9 g/100 ml). At this time, blood pressure was 130/85. In the 34th week, a normal healthy male newborn was delivered by cesarean section. One year later she felt well, her blood pressure was 140/90, serum albumin was 3.4 g/100 ml, urine protein was 1.65 g/24 h and renal function was normal. The patients child was healthy and well developed. CONCLUSION Judicious use of a specific therapy to the underlying renal disease during pregnancy, together with a continuous supervision, can improve outcomes of these particular high-risk conditions.

Patterns of Dietary Intake and Serum Lipids Interact with Proteinuria as Risk Factors for Progression of Chronic Renal Failure

UNLABELLED This prospective study assessed the interactions between patterns of nutrient intake and serum lipids with other risk factors for progression of chronic renal failure. The study cohort consisted of 52 individuals with documented chronic renal failure, 18 women and 34 men, with a mean age of 65 +/- 11 years at the time of recruitment. The dependent variable was the rate of progression of chronic renal failure, which was determined by the slope of the curve generated from five or more values of the reciprocal of serum creatinine (SCr-1) and divided by time (in months of follow-up) for each patient, and recorded in dung/month. The independent variables included dietary factors (phosphorus, protein); serum lipids (total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides); proteinuria; serum phosphorus; serum albumin; serum glucose; and blood pressure. Serum creatinine was drawn in a fasting state and determined using the picric acid technique on five or more occasions for each patient. The mean monthly rate of decline in dL/mg/month was calculated for each patient. The cohort was followed for 1.5 years. Descriptive statistics were determined for all variables. Analysis of principal components was used to generate variables representing patterns of nutrient intake and serum lipids. The outcome variable was modeled using stepwise linear regression which included principal components representing dietary and serum lipid patterns. The Students t test and the F test were used for hypothesis testing. All tests were significant at p < 0.05. RESULTS AND CONCLUSIONS Multicolinearity prevented the inclusion of more than one individual dietary or serum lipid variable into the multiple linear regression model of rate of decline in kidney function. Principal components representing patterns of dietary intake and serum lipids, contributed to the prediction of rate of decline in renal function together with proteinuria.