Occult hepatitis B virus infection in hemodialysis patients in Japan.

Hepatitis B surface antigen is widely used in hepatitis B virus surveillance; patients who test negative for the antigen are judged to be uninfected. However, occult hepatitis B virus infection has been confirmed with hepatitis B virus DNA at low levels in the liver and peripheral blood in patients positive for hepatitis B core antibody or hepatitis B surface antibody, even if they test negative for hepatitis B surface antigen. To investigate the prevalence of occult hepatitis B virus in hemodialysis patients, we performed cross-sectional analysis of 161 hemodialysis patients in two related institutions for hepatitis B surface antigen, hepatitis B core antibody, and hepatitis B surface antibody. Hepatitis B surface antigen, hepatitis B core antibody, or hepatitis B surface antibody was present in 45 patients (28.0%). Hepatitis B virus DNA was present in six patients (3.7%), all of whom also tested positive for hepatitis B core antibody. Hepatitis B surface antibody positivity was unrelated in only one of the six patients. Four of the six patients were positive for hepatitis B surface antigen; however, two (1.3%) of these with occult hepatitis B virus infection were found to be hepatitis B surface antigen negative. Occult hepatitis B virus infection may be missed in hepatitis B virus surveillance using hepatitis B surface antigen alone; therefore, routine hepatitis B core antibody screening is necessary. Patients who test positive for hepatitis B core antibody should undergo further hepatitis B virus DNA testing to enable accurate hepatitis B virus screening.

Optimum second screening point for detection of coronary artery disease in hemodialysis patients without advanced coronary artery disease.

BACKGROUND: Screening for coronary artery disease (CAD) at the initiation of dialysis is a K/DOQI recommendation. However, it remains unclear when screening for CAD should be repeated in patients without significant disease at the time of starting dialysis. The objectives of this study were to determine: (1) the survival of hemodialysis (HD) patients without CAD at the initiation of dialysis, (2) the major predictors of CAD events, and (3) the best time to repeat screening for CAD after the initiation of HD. METHODS: In order to assess the occurrence of de novo major adverse cardiac events (MACE) in HD patients without CAD, we prospectively followed patients who were normal according to screening tests for CAD performed at the initiation of HD. To detect CAD, 177 of 305 new HD patients underwent coronary angiography and/or pharmacologic stress thallium-201 single photon emission computed tomography within 1 month after starting HD. Among these 177 patients, 100 did not have significant CAD and they were followed for a median of 24 months. RESULTS: Five MACE occurred during follow-up, but no events were observed within 1 year after starting HD. All 5 events occurred during the second year of HD (two events occurred immediately after the end of the first year). An increased level of C-reactive protein (CRP) was the only independent predictor of MACE (hazard ratio: 1.39; 95% CI: 1.03-1.78, p = 0.008) according to Cox regression analysis. The optimum cut-off value of CRP for predicting MACE was 3.5 mg/l. The MACE-free rate at 2 years (99 vs. 79%, p = 0.0008) was significantly higher in patients with a CRP level (3.5 mg/l than in those with a level <3.5 mg/l). CONCLUSION: One year after the initiation of HD could be the optimum time to repeat screening for CAD in patients without disease at the initiation of HD. If the serum CRP level is less than 3.5 mg/l, postponing repeat screening for CAD could be considered.

Independent risk factors for progression of coronary atherosclerosis in hemodialysis patients.

Not uncommonly, hemodialysis patients with normal results in myocardial perfusion tests can still have a cardiac event within 2 years of evaluation. We examined possible risk factors for progression of coronary atherosclerosis in hemodialysis patients. We prospectively evaluated ability of myocardial perfusion imaging carried out under pharmacologic stress to predict 2-year outcomes in 77 hemodialysis patients, specifically thallium-201 single-photon emission computed tomography (SPECT) using high-dose adenosine triphosphate as the stressor. The primary end-point was a cardiac event (cardiac death, non-fatal acute coronary syndrome, or hospitalization for acute ischemic heart failure). Factors independently influencing duration until a cardiac event in hemodialysis patients were identified using stepwise multiple regression analysis. Myocardial perfusion defects were shown in 36 patients. Patients with a perfusion defect were more likely to have cardiac events than those with normal perfusion (78% vs. 15%, P < 0.001). Time until occurrence of a cardiac event in hemodialysis patients showed a significant, independent association with known coronary artery disease [regression coefficient (RC) = -3.391, P = 0.046], elevated C-reactive protein (RC = -5.813, P = 0.005), and a reversible myocardial perfusion defect (RC = -7.386, P < 0.001). An analysis based on the 'best cut-off' of CRP as identified on the basis of the ROC curve augmented the positive and negative predict value of CRP for the prediction of coronary events to 65 and 74%, respectively. Myocardial perfusion SPECT and measuring the plasma concentration of CRP might be useful for the prediction of hemodialysis patients with progression of coronary atherosclerosis.

Relationship between serum albumin level before initiating haemodialysis and angiographic severity of coronary atherosclerosis in end-stage renal disease patients.

BACKGROUND: In patients with chronic kidney disease (CKD), although strong associations have been observed between malnutrition and atherosclerosis, the relationship between serum albumin concentration and angiographic changes of coronary artery disease (CAD) remains poorly explored. The goal of the present study was, in patients with CKD, to clarify the relationship between the angiographic severity of CAD and serum albumin concentration reflecting either inflammation or nutrition or both. METHODS: In this study, 100 end-stage renal disease (ESRD) patients were enrolled, who commenced long-term dialysis therapy at our hospital and underwent coronary angiography within 3 months of the first haemodialysis (HD) session. Mean age was 63+/-11 years, 20% of the subjects were female and 62% had diabetes. Severity of CAD was evaluated in terms of (i) number of vessels exhibiting CAD (>or=75% stenosis) and (ii) Gensini score (GS). Clinical characteristics and laboratory findings were recorded at initiation of long-term HD therapy. We then evaluated a possible association with the presence and degree of CAD. RESULTS: Sixty-four patients exhibited signs of CAD. Forty-one among them (64%) had multivessel disease. On univariate logistic regression analysis, age, diabetes and hypoalbuminaemia were significantly associated with multivessel CAD. Univariate linear regression analysis demonstrated a positive correlation of age and diabetes with GS, and an inverse correlation of BMI and serum albumin level with GS. Stepwise regression analysis showed age and serum albumin level to be independently associated with multivessel CAD and GS. The ROC curves demonstrated best cut-off levels of age and albumin for predicting multivessel CAD to be 70 years and 3.15 g/dl, respectively. CONCLUSION: Hypoalbuminaemia at the initiation of dialysis is an important predictor of advanced CAD, particularly in male and in diabetic patients. It may reflect mainly a state of inflammation. However, malnutrition as a confounding factor cannot be entirely excluded.

[Regulation of phosphate balance in the kidney].

The reabsorption of phosphate filtered at glomeruli is mediated by sodium-dependent phosphate (Na/Pi) cotransporter families in the brush border membrane of the proximal tubuli. The type II a Na/Pi cotransporter plays the most important role for renal phosphate reabsorption and is regulated by several factors, e.g. parathyroid hormone (PTH) and fibroblastic growth factor-23. PTH induces endocytosis of the type II a Na/Pi cotransporter from the brush border membrane and subsequent lysosomal degradation, and the decrement of the type II a Na/Pi cotransporter in the brush border membrane leads the phosphate reabsorption inhibition.

Prognostic value of stress myocardial perfusion imaging using adenosine triphosphate at the beginning of haemodialysis treatment in patients with end-stage renal disease.

BACKGROUND: Non-invasive detection of coronary artery disease (CAD) remains difficult in patients with end-stage renal disease (ESRD). This study evaluated the ability of pharmacologic stress myocardial perfusion imaging to predict cardiac events in patients with ESRD. METHODS: A prospective study was carried out in 49 consecutive patients with ESRD. Thallium-201 single photon emission computed tomography (SPECT) using high-dose adenosine triphosphate (ATP) was performed within 1 month of the beginning of haemodialysis. The study end-point was a cardiac event or the 1-year anniversary of the SPECT study. RESULTS: Twenty-four patients (17 diabetics, 57% and seven non-diabetics, 37%) had myocardial perfusion defects. The remaining 25 patients had normal perfusion images. Fifteen patients had non-fatal cardiac events and two patients died of a cardiac cause. All patients who had non-fatal cardiac events underwent myocardial revascularization and survived until the end of follow-up. The 1-year cardiac event-free survival rate was 34% among patients with perfusion defects and 96% among patients without perfusion defects (P<0.001). The presence of a myocardial perfusion defect was the only independent predictor of 1-year cardiac events both in overall (HR, 49.91; 95% CI, 5.15-484.00; P<0.001) and in diabetic patients (HR, 33.72; 95% CI, 2.96-383.5; P = 0.005). Diabetes and an increased C-reactive protein were associated with the progression of CAD. CONCLUSIONS: Normal myocardial perfusion imaging by stress thallium-201 SPECT using high-dose ATP performed within 1 month after the beginning of haemodialysis treatment is a powerful predictor of cardiac event-free survival in patients with ESRD.

Combined assessment of cardiac systolic dysfunction and coronary atherosclerosis used to predict future cardiac deaths after starting hemodialysis.

BACKGROUND/AIMS: Identification of end-stage renal disease (ESRD) patients at high risk for cardiac events is important for clinical dialysis management. The present study determined whether the combination of cardiac function and coronary atherosclerosis could predict future cardiac events after starting renal replacement therapy (RRT). METHODS: We prospectively assessed left ventricle ejection fraction (EF) and Gensini score (GS) using angiographic severity of coronary atherosclerosis in 88 consecutive ESRD patients [mean age 62 years; 69 males (78%); 55 patients (64%) with diabetic nephropathy] at the initiation of RRT. EF was analyzed by echocardiogram, and GS was scored by coronary angiography within 3 months after starting RRT. The study end point was cardiac death. For analysis of the association between cardiac death and EF and GS measures, the univariate and multivariate Cox proportional hazards model was used. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value, and accuracy of event-free prediction were evaluated. RESULTS: Twenty-four patients (27%) had low cardiac function (EF <50%; low EF) and 44 patients (50%) had severe coronary atherosclerosis (GS >15; high GS). During a follow-up period of 3 years, cardiac death occurred in 21 patients (24%). The PPV of low EF and high GS was 42 and 39%, respectively; the highest PPV (53%) was obtained when low EF and high GS were combined. The cumulative survival rate at 5 years in patients with both low EF and high GS was significantly lower than those with high EF and low GS (91 vs. 22%, p < 0.0005). CONCLUSION: The combined assessment of cardiac function and coronary atherosclerosis at the initiation of RRT strongly predicts future cardiac events.

Angiographical severity of coronary atherosclerosis predicts death in the first year of hemodialysis.

BACKGROUND: Cardiac deaths and events tend to cluster within the early-phase after starting dialysis. Our goal is to clarify the influence of severity of coronary atherosclerosis on early-phase death after starting hemodialysis (HD) therapy. PATIENTS AND METHODS: Eighty-three consecutive patients [mean age 62 years; male/female 64/19; diabetic nephropathy in 50 (54%)] with end-stage renal disease who admitted to our hospital to initiate regular HD treatment, and then received coronary angiography within 3 months after first dialysis therapy, were eligible for this study. Angiographical severity of coronary atherosclerosis was scored by numerically using Gensini scoring system. The patients who died within one year from starting HD were compared with those who survived as control by means of logistic regression analysis. RESULTS: Of 83 patients, 12 (14%) died less than one year after starting dialysis therapy. Of these 12 patients, nine died for cardiac causes. Confirmed predictors of death from cardiac cause were older age (>70 years), lower mean blood pressure (<100 mmHg), presence of ischemic heart disease (IHD), myocardial infarction (MI), angina pectoris (AP), chronic heart failure (CHF), poor cardiac function, abnormal wall motion of left ventricule (LV) and angiographical severity of coronary atherosclerosis by univariate model. Adjusting for confounding variables by multivariate model, only severity of coronary atherosclerosis (Gensini score >40 points) had a powerful influence, increasing risk for cardiac cause of early-phase death by about 17 times. CONCLUSIONS: Severity of coronary atherosclerosis predicts death in the first year of HD. These findings suggest that the strategy for prevention of coronary atherosclerosis should be instituted during the early phase of chronic renal failure.