The influence of hepatitis C infection activity on oxidative stress markers and erythropoietin requirement in hemodialysis patients

We sought to expose the possible effect of hepatitis C virus (HCV) infection on oxidative stress indicators, nutritional status, and erythropoietin (rHuEPO) requirements in maintenance hemodialysis (MHD) patients. A total of 111 MHD patients (69 males, 42 females; mean age 51.3 +/- 13.0 years; MHD duration 78.5 +/- 52.1 months) and 46 healthy controls were enrolled in the study. We excluded patients with hepatitis B infection or malignancy. Indicators for oxidative status were studied in plasma samples obtained at the beginning of a clinically stable MHD session. Measurements were performed for plasma superoxide dismutase, glutathione peroxidase (antioxidative agents), and malonyldialdehyde (MDA; oxidative agent) by spectrophotometric methods. All patients were analyzed for the presence of anti-HCV; positive patients were also evaluated for the presence of HCV RNA. MHD patients were divided into three groups according to HCV infection status: group I (anti-HCV-positive, HCV-RNA-negative; n = 22); group II (anti-HCV-positive, HCV-RNA-positive; n = 22), and group III (anti-HCV-negative; n = 67). According to the analyses, MHD patients showed higher plasma oxidative stress indicators and lower antioxidative indicator levels compared to controls (P < .0001). MHD patients also displayed lower albumin and higher C-reactive protein (CRP) levels compared to controls (P < .0001). Antioxidant levels were decreased significantly from group I to III (P < .0001). MDA levels significantly increased from group I to III (P < 0.01). HCV-RNA-positive patients showed lowest albumin and highest CRP levels and rHuEPO requirements. Although alanine transferase (ALT) levels were in the normal range, group II patients had significantly higher ALT levels than the other groups (P < .01). In conclusion, we observed negative effects of active HCV infection on oxidative stress and rHuEPO requirements. In contrast, we detected that clinically inactive HCV infection was associated with reduced oxidative stress and rHuEPO requirements compared with active HCV infection and HCV-negative patients.

An obesity drug sibutramine reduces brain natriuretic peptide (BNP) levels in severely obese patients

OBJECTIVES

Sibutramine is a selective inhibitor of the reuptake of monoamines. Plasma levels of brain natriuretic peptide (BNP) appear to be inversely associated with body mass index (BMI) in subjects with and without heart failure for reasons that remain unexplained. The aim of this study was to investigate the possible influence of sibutramine treatment on BNP levels in severely obese patients.

METHODS

Fifty-two severely obese female patients with BMI > 40 kg/m(2) were included to this study. The women were recommended to follow a weight-reducing daily diet of 25 kcal/kg of ideal body weight. During the treatment period, all patients were to receive 15 mg of sibutramine once a day. Blood chemistry tests were performed before the onset of the medication and after 12 weeks of treatment.

RESULTS

None of the subjects was withdrawn from the study because of the adverse effects of sibutramine. Body weight (108.8 +/- 13.3 kg vs. 101.7 +/- 15.6 kg, p < 0.001), BMI (44.6 +/- 4.6 kg/m(2) vs. 41.8 +/- 5.7 kg/m(2), p < 0.001) and BNP [8.6 (0.5-49.5) ng/l vs. 3.1 (0.2-28.6) ng/l, p = 0.018] levels were significantly decreased after 12 weeks of sibutramine treatment. Total cholesterol (5.19 +/- 0.90 mmol/l vs. 4.82 +/- 1.05 mmol/l respectively; p < 0.001), low-density lipoprotein-cholesterol (3.26 +/- 0.86 mmol/l vs. 2.99 +/- 0.40 mmol/l respectively; p = 0.008), levels were significantly decreased; however, there was no significant alteration in high-density lipoprotein-cholesterol and triglyceride levels.

CONCLUSION

This study has shown a decrease in BNP levels which may lead to improvement in cardiac outcome after sibutramine treatment. Further randomised studies are needed to be conducted to clarify the relationship between sibutramine and BNP.

Short-term isotretinoin treatment decreases insulin-like growth factor-1 and insulin-like growth factor binding protein-3 levels: does isotretinoin affect growth hormone physiology?

BACKGROUND

Isotretinoin is an effective treatment for acne vulgaris. However, it has numerous side-effects. It was previously reported that serum growth hormone (GH) levels decreased with isotretinoin treatment.

OBJECTIVES

To analyse whether isotretinoin has any effects on insulin-like growth factor-1 (IGF-1), insulin-like growth factor binding protein-3 (IGFBP3) and GH levels.

METHODS

Forty-seven patients aged 21.5 +/- 5.1 years (mean +/- SD) with acne vulgaris were included in this study. Isotretinoin therapy was initiated at a dose of 0.5-0.75 mg kg(-1) daily and then adjusted to 0.88 mg kg(-1) daily as maintenance dosage after 1 month. Screening for biochemical and hormonal parameters was performed just before initiation and after 3 months of isotretinoin treatment.

RESULTS

IGF-1 and IGFBP3 levels decreased significantly after treatment (P < 0.01), while GH levels did not change. Post-treatment, significant increases were seen in aspartate aminotransferase, total cholesterol, low-density lipoprotein cholesterol, triglycerides and low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio (P < 0.0001) while high-density lipoprotein cholesterol levels were significantly decreased (P < 0.0001).

CONCLUSIONS

Isotretinoin therapy may have an effect on GH physiology, and further studies are needed to understand this association.

Influence of oxidative stress and inflammation on rHuEPO requirements of hemodialysis patients with CRP values "in normal range"

AIMS

We sought to evaluate influences of oxidative stress (OS) on rHuEPO requirements in hemodialysis patients without chronic inflammation.

METHODS

Sixty-eight hemodialysis patients and 46 healthy controls underwent measurements plasma levels of antioxidative agents, such as glutathione peroxidase (GPX), superoxide dismutase (SOD), and oxidative compounds including malonyldialdehyde (MDA). We retrospectively analyzed the last 3 months' rHuEPO requirements, iron indices, and CRP levels.

RESULTS

Plasma levels for SOD, GPX, and MDA were 974.4+/-216.4 U/gHb, 44.4+/-13.6 U/gHb, 10.0+/-2.0 nmol/mL, respectively yielding results that were different from healthy controls (P<.0001). Increased OS negatively correlated with hemoglobin levels (P<.0001) and positively correlated with rHuEPO requirements (P<.01). Increased antioxidative capacity positively correlated with hemoglobin levels (P<.0001) and negatively correlated with rHuEPO requirements (P<.0001). For further analyses, hemodialysis patients were subgrouped according to rHuEPO requirements as group I (lowest 1/3, n=23), group II (moderate 1/3, n=23) and group III (highest 1/3, n=22). Group III displayed the highest MDA (P<.05), the lowest SOD (P<.0001), and comparable GPX (P<.05) levels. Group III also had the highest CRP and the lowest albumin levels compared with the others (P<.01).

CONCLUSION

OS has strong adverse influences on rHuEPO responses of HD patients with "normal" CRP levels, but it should not be forgotten that CRP levels in the "normal" range may still reflect ongoing microinflammation.

Transvaginal sonography in the diagnosis of adenomyosis: which findings are most accurate?

OBJECTIVES

To evaluate the accuracy of various transvaginal sonographic findings in adenomyosis by comparing them with histopathological results and to determine the most valuable sonographic feature in the diagnosis of adenomyosis.

METHODS

In this prospective study, 70 consecutive patients scheduled for hysterectomy underwent preoperative transvaginal sonography. If at least one of the following sonographic features was present, a diagnosis of adenomyosis was made: heterogeneous myometrial echotexture, globular-appearing uterus, asymmetrical thickness of the anteroposterior wall of the myometrium, subendometrial myometrial cysts, subendometrial echogenic linear striations or poor definition of the endometrial-myometrial junction. The sonographic features were compared with the histopathological results.

RESULTS

The prevalence of adenomyosis was 37.1% (26/70 patients). The sensitivity, specificity, positive (PPV) and negative (NPV) predictive values and accuracy of transvaginal ultrasound for the diagnosis of adenomyosis were 80.8%, 61.4%, 55.3%, 84.4% and 68.6%, respectively. We found that a regularly enlarged uterus with a globular appearance, subendometrial echogenic linear striations and myometrial cysts had the highest accuracy for the diagnosis of adenomyosis. Of all findings evaluated, heterogeneous myometrium was the most common in patients with adenomyosis (21/26 patients), but it had a poor specificity. The presence of subendometrial linear striations was the most specific sonographic feature (95.5%) and it had the highest PPV (80.0%) for the diagnosis of adenomyosis.

CONCLUSIONS

The presence of subendometrial echogenic linear striations, a globular configuration and myometrial cysts on transvaginal ultrasound supports the diagnosis of adenomyosis. Among the transvaginal ultrasound diagnostic findings of adenomyosis, subendometrial linear striations have the highest diagnostic accuracy.

Possible Influence of Vitamin D Receptor Gene Polymorphisms on Recombinant Human Erythropoietin Requirements in Dialysis Patients

BACKGROUND

Vitamin D receptor (VDR) gene polymorphisms have been widely studied, especially to analyze their effects on calcium-phosphorus metabolism and secondary hyperparathyroidism in patients on dialysis. In this study, we sought to investigate the possible effects of these polymorphisms on the anemia of renal failure and recombinant human erythropoietin (rHuEPO) responses among patients receiving hemodialysis.

METHODS

One hundred twenty-eight patients (52 females/76 males) underwent genotyping for the insertion/deletion Bsml (B-->b, restriction site, exon VIII-->IX) and Tagl (T-->t, 352 exon IX) VDR gene polymorphisms. The mean value of the last 6 months' monthly evaluated laboratory values (C-reactive protein, hemoglobin, iron indices, PTH, and albumin) and clinical findings (rHuEPO requirement, cumulative iron supplementation doses, and body weight) were analyzed retrospectively excluding patients with chronic inflammation, hemolytic anemia, or active blood loss such as gastrointestinal bleeding.

RESULTS

Mean age and dialysis durations were 41.5 +/- 11.8 years and 91.8 +/- 45.3 months, respectively. Polymorphism percentages were as follows: Bsml; BB/Bb/bb: 32.2/63.6/4.2 and Tagl; TT/Tt/tt: 40.5/55.4/4.1%, respectively. BB variant of Bsml gene was related to lower rHuEPO needs (P < .05) and also higher hemoglobin levels (P < .005) when compared with the Bb/bb variant. Considering Tagl variants, transferrin saturation levels were lower (P < .03) among patients with the Tt/tt variant, but there was no other significant difference in the mean values of other data between TT and Tt/tt variants.

CONCLUSION

The BB variant of Bsml was related to decreased rHuEPO requirements to achieve higher hemoglobin levels among maintenance hemodialysis patients without chronic inflammation.

Additional Effect of Hyperparathyroidism on Inflammatory Status and rHuEPO Requirements in Hemodialysis Patients

BACKGROUND

The aim of this study was to analyze the effects of elevated parathyroid hormone (iPTH) and C-reactive protein (CRP) on rHuEPO requirements and associated clinical and biochemical parameters of hemodialysis patients.

METHODS

A total of 127 hemodialysis patients were included. Laboratory values from the previous 3 months (monthly measured CRP, iPTH, albumin, prealbumin, calcium, phosphorus, and hemoglobin) and clinical findings (rHuEPO requirements, iron supplements, Kt/V) were recorded retrospectively. Patients were subgrouped according to presence of hyperparathyroidism (mean iPTH > 350 pg/mL) and chronic inflammation (mean CRP > 8.5 mg/L) as group I (low iPTH, low CRP, n = 32), group II (high iPTH, low CRP, n = 32), group III (low iPTH, high CRP, n = 32), and group IV (high iPTH, high CRP, n = 31).

RESULTS

We found that group IV had lowest hemoglobin (P < .0001, .0001, .01, respectively), albumin (P < .0001), prealbumin (P < .0001, .0001, .02, respectively), and highest rHuEPO requirements (P < .0001, .0001, .01, respectively) compared to other groups despite of similar iron indices. Group III also had lower albumin (P < .002, .0001, respectively), prealbumin (P < .001, .01, respectively), hemoglobin (P < .001, .005, respectively), but higher rHuEPO requirements (P < .01) compared to group I and group II.

CONCLUSIONS

We propose that hyperparathyroidism increases rHuEPO requirements and aggravates the negative effects of chronic inflammation in hemodialysis patients.

Hepatitis C infection in hemodialysis patients: Protective against oxidative stress?

Hepatitis C virus (HCV) infection is a common problem that increases morbidity and mortality in hemodialysis patients. These patients are also at risk of increased oxidative stress. The aim of this study was to evaluate possible interactions between HCV infection and oxidative stress indicators in a group of hemodialysis patients awaiting transplantation. We evaluated 73 patients (29 women, 44 men; ages, 49.3 +/- 13.3 years; dialysis duration, 81.7 +/- 48.8 months; Kt/V > or = 1.3). Indicators of plasma oxidative status were monitored at the beginning of a clinically stable hemodialysis session. Measurements were performed for plasma superoxide dismutase (SOD), glutathione peroxidase (GPX), and malonyldialdehyde (MDA) by spectrophotometric methods. We retrospectively recorded the prior year's monthly laboratory values for alanine aminotransferase (ALT), C-reactive protein (CRP), albumin, lipids, homocysteine, Lp(a), calcium, phosphorus, intact parathyroid hormone, and predialysis blood urea nitrogen (BUN) creatinine, as well as clinical findings of body mass index and pre- and postdialysis blood pressures. We excluded patients with chronic inflammation (mean CRP levels > or = 10 mg/L) or HCV infection of duration <12 months or clinically advanced liver failure. Twenty-six patients had HCV. The sex distribution, mean age, and dialysis duration were similar between groups. HCV-infected patients showed significantly lower levels of MDA, albumin, total cholesterol, triglyceride, predialysis creatinine, and phosphorus. Antioxidative indicator levels were also higher in the HCV group, but they were not statistically significant. In conclusion, HCV infection in dialysis patients is associated with decreased levels of plasma oxidative load.

Pulmonary Function in Renal Transplant Recipients and End-Stage Renal Disease Patients Undergoing Maintenance Dialysis

The aim of this study was to reveal the pulmonary function status of renal transplant recipients and chronic renal failure patients on hemodialysis or continuous ambulatory peritoneal dialysis. The study involved 73 subjects, including 49 patients who were either on peritoneal dialysis (n = 22) or hemodialysis (n = 27), and 24 renal transplant recipients. The spirometry results revealed significantly higher residual volume and total lung capacity in the hemodialysis and peritoneal dialysis groups than in the transplantation group. Forced expiratory flow between 25% and 75% of vital capacity was slightly below normal in the dialysis patients. Preservation of diffusion capacity of the lung for carbon monoxide was noted in the hemodialysis group (112.4%). Inspiratory and expiratory muscle strength was reduced in all groups. Only type of dialysis was correlated with this reduction. Inspiratory muscle strength in the peritoneal dialysis group (49.9%) was significantly lower than in the transplantation and hemodialysis groups (54.7% and 66.5%, respectively). The spirometry findings suggest that small-airway disease causes increased residual volume and total lung capacity (hyperinflation) in hemodialysis and peritoneal dialysis patients and that this airway obstruction subsides after renal transplantation. Preserved diffusion capacity in the hemodialysis group was attributed to the use of biocompatible dialyzer membranes. Renal failure complications may be the main explanation for global respiratory muscle weakness in dialysis patients, whereas corticosteroid therapy might be the primary cause in kidney graft recipients. Significantly lower inspiratory muscle strength in the peritoneal dialysis group suggests that presence of intra-abdominal dialysate might interfere with diaphragmatic contraction.

Prevalence and Etiology of Anemia in Renal Transplant Recipients

We aimed to define the prevalence of anemia and possible causes for it in a group of renal transplant recipients. A total of 229 recipients (65 women; age 36.1 +/- 11.8 years; minimum posttransplant duration, 3 years) were included. Patients with iron, vitamin B(12), and folic acid deficiencies were excluded. Patients were grouped according to number of posttransplant years completed with functioning grafts (3, 5, or 10 years). Demographic data, donor information, HLA mismatches, acute rejection episodes, biochemical parameters, and medications received during the 3 months before transplant and at 3, 5, and 10 years posttransplant were collected retrospectively. The anemia threshold was 13 g/dL for men and 12 g/dL for women. Anemia prevalence was 41.5%, 35.3%, and 93.2% at 3, 5, and 10 years, respectively. Anemic patients had higher creatinine levels for all years. In the anemic patients, hemoglobin values were lower in the pretransplant period than at 3 and 5 years. Anemic patients had higher HLA mismatches for the same years. Three-year hemoglobin levels were positively correlated with pretransplant hemoglobin and negatively correlated with creatinine levels and HLA mismatches. Five-year hemoglobin levels were positively correlated with pretransplant hemoglobin and albumin levels. Ten-year hemoglobin levels were positively correlated with pretransplant hemoglobin and albumin values but negatively correlated with creatinine levels and HLA mismatches. The prevalence of anemia in renal transplant recipients increases in parallel with posttransplant duration. Hemoglobin levels in these patients are closely related with pretransplant hemoglobin, follow-up creatinine levels, and HLA mismatches.

Angiotensin-Converting Enzyme and Endothelial Constitutive Nitric Oxide Synthase Polymorphisms in Turkish Renal Transplant Population and Possible Influence on Renal Artery Atherosclerosis and Graft Survival

BACKGROUND

Renal transplant recipients are prone to accelerated atherosclerosis secondary to immunosuppressants, which may decrease graft survival. We sought to analyze the effects on renal graft survival of atherosclerotic degeneration in the renal artery and the influence of angiotensin-converting enzyme (ACE) endothelial constitutive nitric oxide synthase (ecNOS) gene polymorphisms.

METHODS AND PATIENTS

Thirty three renal transplant recipients (25 men) of mean age 28.4 +/- 9.6 years, received organs from 11 living related donors and were followed for at least 36 months. Genotyping was performed for the insertion/deletion ACE (I/D), angiotensin (AGT) (M-->T, 235), angiotensine 1 receptor (A-->C, 1166), angiotensin 2-receptor (A-->G, 1223), and ecNOS (b-->a, intron4) gene polymorphisms. Renal artery biopsies were performed during transplantation surgery to analyze the presence of atherosclerosis.

RESULTS

Pathological examination indicated that 18 donor specimens and nine recipient specimens had atherosclerotic degeneration. Survival analysis (36 months) indicated that graft survival rates of recipients who had atherosclerosis in the renal artery and who received an organ from donors with an atherosclerotic renal artery were shorter than in their counterparts (P = .02, P = .04, respectively). Comparison of genetic variations of recipients revealed that CC/TC variation of AGT was higher in patients with atherosclerosis (81% vs 53%, P = .03). There was no significant difference between groups in means of other gene polymorphisms.

CONCLUSION

Renin-angiotensin system gene polymorphism analysis of patients in renal transplantation waiting list may provide information about allograft survival and posttransplant atherosclerotic degeneration at graft vasculature of young transplant recipients.

Vitamin D Receptor BsmI and TagI Gene Polymorphisms in a Turkish ESRD Population: Influences on Parathyroid Hormone Response

BACKGROUND

Clinical presentation and complications of end-stage renal disease patients are influenced by many environmental and genetic factors. In this study we sought to define the frequencies of BsmI and TagI vitamin D receptor gene polymorphisms and their influences on clinical presentations in the Turkish end-stage renal disease population.

METHODOLOGY AND PATIENTS

Hemodialyzed patients (n = 186; 111 male, 75 female) were genotyped for the insertion/deletion BsmI (B --> b, restriction site, exon VIII --> IX), TagI (T --> t, 352 exon IX) vitamin D receptor gene polymorphisms. The previous 12 months of laboratory values (C-reactive protein, intact parathyroid hormone, albumin, calcium, phosphorus, CaxP product) and clinical findings (vitamin D requirement, body weight) were analyzed retrospectively.

RESULTS

Mean age and follow-up periods were 42.1 +/- 12.6 years and 76.3 +/- 43.9 months, respectively. Polymorphism percentages were BsmI; BB/Bb/bb: 28.9/65.3/5.8% and TagI; TT/Tt/tt: 36.7/60.5/2.8%, respectively. Further analysis revealed that the TT variant of TagI was related to hyperparathyroidism (P < .05). Analysis of the data after regrouping patients according to iPTH levels (0 to 249; 250 to 499; > or =500 pg/mL) and hemodialysis duration (<60 versus > or =60 months) revealed an influence of TT variation on hyperparathyroidism as a function of increased hemodialysis duration and higher iPTH levels (P < .005).

CONCLUSION

TT variants of the TagI vitamin D receptor gene influence the development of hyperparathyroidism in hemodialysis patients, an influence that becomes more evident in patients with longer hemodialysis duration.