The possible impact of dialysis modality on cognitive function in chronic dialysis patients.

Chronic kidney disease (CKD) is a growing public health problem. Individuals in all stages of CKD are at higher risk for development of cognitive impairment and this may be a major determinant in their quality of life (QOL). The prevalence of cognitive deficits is particularly high in subjects with end-stage renal disease (ESRD). While it is sufficiently well documented that ESRD is linked with a change in cognitive function, little is known about the influence of different dialysis modalities on cognitive function. The effect of dialysis modality on risk of cognitive impairment is unclear. Some data suggest that patients with ESRD treated with chronic ambulatory peritoneal dialysis (CAPD) had consistently better cognitive function than patients treated with haemodialysis (HD). We concluded that the previously observed apparent difference between two modalities of dialysis treatments resulted either from very low dialysis delivery or comparison with poorly matched controls. Regarding these data from previous studies we hypothesised that well-dialysed, well-nourished and medically stable HD patients had no cognitive dysfunction in comparison with well-dialysed, well-nourished, medically stable and demographically matched CAPD patients. Also, future studies are needed to differentiate between modality as a risk factor from the factors contributing to selection bias among patients choosing CAPD over HD.

A long-lasting topical deltamethrin treatment to protect dogs against visceral leishmaniasis.

To develop long-lasting, topical pour-on insecticides for dogs to control zoonotic visceral leishmaniasis, two deltamethrin-based formulations (emulsifiable concentrate [EC] and suspension concentrate [SC]) were tested for their efficacy against the phlebotomine sandfly Lutzomyia longipalpis Lutz & Neiva (Diptera: Psychodidae), vector of Leishmania infantum Nicolle (Kinetoplastida: Trypanosomatidae). The entomological outcomes tested were anti-feeding effect (proportion of female sandflies unfed), lethal effect (24-h female sandfly mortality) and these two effects combined, and the insecticide persistence time at 50% (residual activity, RA50) and 80% (RA80) efficacy. On initial application, the proportions of female flies that demonstrated anti-feeding activity or were killed were similar for both formulations, at 0.93 (95% confidence interval [CI] 0.856-0.977) vs. 0.81 (95% CI 0.763-0.858) (anti-feeding) and 0.86 (95% CI 0.787-0.920) vs. 0.76 (95% CI 0.698-0.817) (24-h mortality) for EC and SC, respectively. The RA(50) rates for anti-feeding and mortality caused by the EC formulation were 4.7 months (95% CI 4.18-5.84) and 2.5 months (95% CI 2.25-2.90), respectively, compared with 1.1 months (95% CI 0.96-1.15) and 0.6 months (95% CI 0.50-0.61), respectively, for the SC formulation. The RA(50) for the combined anti-feeding and mortality effects of EC was 5.2 months (95% CI 4.73-5.96), compared with only 0.9 months (95% CI 0.85-1.00) for the SC formulation. The four- to six-fold superior residual activity of the EC formulation was attributed to the addition of a solvent-soluble resin in the formulation which improved fur adhesion and acted as a reservoir for the slow release of the active ingredient. These results identify the potential of such a low-cost formulation to reduce the inter-intervention interval to 5-6 months, similar to that recommended for deltamethrin-impregnated dog collars or for re-impregnation of conventional bednets, both of which are currently used to combat Leishmania transmission. Finally, a novel bioassay was developed in which sandflies were exposed to fur from treated dogs, revealing no detectable tolerance (24-h mortality) in wild-caught sandflies to the insecticide formulations up to 8 months after the initiation of communitywide application of the insecticides to dogs.

Two spent dialysate samples are sufficient for hemodialysis efficacy assessment.

INTRODUCTION: The measure of dialysis efficacy is expressed as Kt/V value (calculated from predialysis and postdialysis blood urea concentration). The aim of this study was to assess the possibility of direct calculation of Kt/V value from two spent dialysate samples by using the regular blood-based Kt/V calculation formula with dialysate samples used as surrogates for blood samples, and to detect the most appropriate couple of dialysate samples for Kt/V estimation. PATIENTS AND METHODS: Fifty-two single hemodialysis treatments in 34 anuric patients on chronic bicarbonate low-flux hemodialysis were observed. Kt/V values according to Daugirdas formula from two blood samples and from two dialysate samples were calculated. RESULTS: Kt/V values calculated according to Daugirdas 2 nd generation formula from blood samples (Kt/V sp Daugirdas) were in significant correlation with all Kt/V values obtained from two spent dialysate samples. The highest correlation coefficient (r = 0.74, p < 0.001) and the least standard error of mean of the differences were found between Kt/V sp Daugirdas and value obtained with substitution of urea concentration from dialysate samples taken 60 minutes after dialysis start and at the end of the dialysis into Daugirdas 2 nd generation formula (Kt/V D C D(60) -C D(e) ), which can be expressed as a equation of linear regression y = 0.47 + 0.86x. The highest correlation coefficient (r =0.74, p < 0.001) was found between Kt/V sp Daugirdas values equilibrated according to Daugirdas rate formula, and Kt/V D C D(60) -C D(e) value, which can also be expressed as an equation of linear regression y = 0.43 + 0.73x. CONCLUSION: The results of this study clearly show the sufficiency of only two spent dialysate samples for direct estimation of the Kt/V values, with no blood sample required.

Seasonal variations of clinical and biochemical parameters in chronic haemodialysis.

INTRODUCTION: Seasonal variations in clinical and laboratory variables occur commonly among chronic haemodialysis patients. In order to demonstrate seasonal differences, we prospectively compared biochemical and clinical parameters in a group of chronically haemodialysed patients living in South Croatia, a region with a Mediterranean climate. MATERIALS AND METHODS: Data were processed on 135 single dialysis treatments involving a group of 34 anuric chronic haemodialysis (HD) patients. Outcomes were measured at 3-month intervals, in March, June, September and December. RESULTS: The seasonal differences were found in phosphorus (P = 0.001), creatinine before HD (P <0.001), creatinine after HD (P = 0.005), alkaline phosphatase (P = 0.012), alanine aminotransferase (P = 0.042), urea before HD (P = 0.039), albumins (P <0.001), total cholesterol (P <0.001), low-density lipoprotein (LDL) cholesterol (P <0.001), high-density lipoprotein (HDL) cholesterol (P <0.001), glucose (P = 0.033), and ultrafiltration per HD (P = 0.037). When the data were grouped into cold (March and December) and mild (June and September) months, we found differences in phosphorus (1.48 +/- 0.47 versus 1.72 +/- 0.51, P = 0.005), alkaline phosphatase (119.46 +/- 69.03 versus 169.78 +/- 107.98, P = 0.002), urea before HD (27.13 +/- 5.35 versus 24.40 +/- 5.99, P = 0.006), albumins (37.92 +/- 5.17 versus 40.58 +/- 5.69, P = 0.006), total cholesterol (4.93 +/- 0.93 versus 5.30 +/- 0.93, P = 0.023), LDL cholesterol (2.85 +/- 1.04 versus 3.23 +/- 0.87, P = 0.046), glucose (4.62 +/- 1.15 versus 5.57 +/- 1.46, P = 0.004), and ultrafiltration per HD (3.57 +/- 1.18 versus 2.97 +/- 1.20, P = 0.004). CONCLUSION: In Mediterranean climates, seasonal differences in predialysis urea concentration and ultrafiltration rate per dialysis could be attributed to different food and water intake. The seasonal differences in blood concentration of phosphorus, alkaline phosphatase, total cholesterol, LDL cholesterol, and glucose might be the results of neurohormonal influences. This climate has no impact on haemoglobin and blood pressure levels.

HIV infection and risk behaviour of commercial sex workers and intravenous drug users in Slovakia.

INTRODUCTION: Aim of the study was to determine risk behaviour and HIV prevalence among commercial sex workers (CSWs) and intravenous drug users (IDUs) in streets of Bratislava and B. Bystrica, SR. METHODS: HIV antibodies were tested from saliva using ELISA test. Anonymous questionnaire was completed. RESULTS: 121 persons (61 men and 60 women) were involved in the sociological study. Mean age of the participants was 21.9 years. 185.1% of subjects were from Bratislava. 108 participants were tested for the presence of HIV-antibodies, one was confirmed HIV-positive (0.82%). In the past 47.9% of participants and 22.3% of their partners were tested for the presence of HIV-antibodies. 10.8% of subjects proclaimed that they suffered from other sexually transmitted infection (STI) in the past HIV testing of participants significantly correlated with the testing for other STI (p<0.002) as well as with HBV/HCV (p<0.001). 58 participants were using tattooing (47.9%). 46.3% of all participants never used condoms with partners. 31.4% of respondents proclaimed disruption of condom during sexual intercourse. Significant correlation was found between testing of participants for other STI and usage of condoms with their partners (p<0.013). Women used condoms more often by sexual contacts with partners than men used condoms (p<0.094). They were also significantly more tested for other STI in the past (p<0.021) and they suffered from other STI more often than men (p<0.033). 26.5% of person--only women--were involved in commercial sex work. 93.5% of them were taking drugs as well, 21.8% suffered for other STI in the past They were working in sex business on average for 26 months. The average number of their clients per week was 12.3. CSWs used condoms more often with clients than with partners. 98.2% of all participants were taking drugs, 93% of them intravenously. 24.6% of IDUs always used new or their own needles and syringes, while 69.4% shared equipments with the other users. IDUs drug users used condoms significantly less often with their partners than did CSWs (p<0.006). CSWs were significantly more often tested for other STI (p<0.001) and they also more often suffered for other STI than IDUs (p<0.045). CONCLUSION: More effort should be done to decrease risk behaviour revealed in the groups of CSWs and drug users.

Mean arterial pressure and pulse pressure are associated with different clinical parameters in chronic haemodialysis patients.

The mean arterial pressure (MAP) usually serves as an expression of blood pressure in patients on chronic haemodialysis (PCHD), instead of using solely systolic or diastolic pressure. Pulse pressure (PP) has been recognized as an important correlate of mortality in PCHD. We conducted this study in order to demonstrate clinical and biochemical determinants and variability of predialysis and postdialysis MAP and PP values. A total of 136 single haemodialysis (HD) treatments in 23 subjects (PCHD, 11 male and 12 female patients) were processed during 15 months. MAP before HD was in negative correlation with haemoglobin (P<0.001) and body mass index (BMI) (P<0.001), and in positive correlation with weekly erythropoietin dosage (P=0.017). MAP after HD was in negative correlation with haemoglobin (P<0.001), ultrafiltration per HD (P=0.015), and BMI (P=0.001), and in positive correlation with weekly erythropoietin dosage (P=0.003). PP before HD was in negative correlation with parathyroid hormone (PTH) level (P=0.020), haemoglobin (P<0.001), ultrafiltration per HD (P=0.001), and years on the chronic HD treatment (P=0.001), and in positive correlation with weekly erythropoietin dosage (P<0.001) and age (P<0.001). PP after HD was in significant negative correlation with PTH (P=0.015), haemoglobin (P=0.005), ultrafiltration per HD (P<0.001), BMI (P=0.003), and in positive correlation with weekly erythropoietin dosage (P<0.001) and age (P=0.004). Multiple regression analyses unveiled the strongest and negative correlations between MAP before HD and BMI (beta=-0.37, P=0.01); MAP after HD and haemoglobin (beta=-0.36, P=0.01); PP after HD and ultrafiltration/body weight ratio (beta=-0.41, P<0.001). The strongest and positive correlation was found between PP before HD and erythropoietin dosage per week (beta=0.51, P&<0.001). In conclusion, our findings support the assumption that PP and MAP are associated with different clinical parameters. PP values have advantages as the method of blood pressure expression.

Seasonal variations of chronic hemodialysis dose in South Croatia.

INTRODUCTION: The dialysis parameters are used for prescribing the dose of dialysis therapy. Delivered dialysis dose could be calculated from predialysis and postdialysis blood urea concentrations. Seasonal variations in some clinical and laboratory variables occur among chronic hemodialysis patients. Seasonal variations in chronic hemodialysis dose have not been investigated. We prospectively compared hemodialysis adequacy parameters in order to demonstrate its seasonal differences. SUBJECTS AND METHODS: Data were processed on 201 single dialysis treatments involving a group of 51 anuric chronic hemodialysis patients. The study period was 12 months. Four measurements per subject were obtained (in January, April, July, and October). RESULTS: We could not demonstrate seasonal variability in prescribed and delivered hemodialysis dose, in "delta" values (absolute differences between prescribed and delivered dialysis doses for the same hemodialysis treatment), or in ultrafiltration per hemodialysis. Seasonal differences were found in blood urea concentrations before and after hemodialysis (p = 0.001, p = 0.010). When the data were grouped into two groups: cold (January and October) and mild (April and July) months; we could not demonstrate significant differences in dialysis adequacy parameters, but there were differences in blood urea concentration before hemodialysis (26.06 +/- 14.73 vs. 24.35 +/- 4.50, p = 0.004), blood urea concentration alter hemodialysis (10.24 +/- 2.96 vs. 9.43 +/- 2.60, p = 0.019), and ultrafiltration per hemodialysis (3.36 +/- 1.13 vs. 3.10 +/- 1.11, p = 0.046). CONCLUSION: Based of the results of this investigation conducted on chronically hemodialyzed patients in the mild Mediterranean climate in South Croatia, Europe; we have concluded that clinicians should not pay attention to season when they prescribe hemodialysis dose or analyze delivered hemodialysis dose.

Oxidative modification of low-density lipoproteins and the outcome of renal allografts at 1 1/2 years.

BACKGROUND: Previous studies reported a significant association between hyperlipidemia of the recipient and chronic allograft nephropathy (CAN). However, the nature and the pathogenic mechanism of circulating lipid abnormalities in CAN remain unclear. METHODS: In a prospective study of 50 consecutive adult recipients of a cadaveric renal allograft, we investigated the impact of lipid abnormalities on the outcome of the graft at 1 1/2 years. Besides morphometric analysis of implantation and protocol biopsies, clinical and biochemical variables were studied at three-month intervals. Plasma concentrations of oxidized low-density lipoprotein (OxLDL) were determined by means of enzyme-linked immunosorbent assay. Immunohistochemical staining for OxLDL and macrophages was performed on paired renal biopsies. Study end points were the fractional interstitial volume and the 24-hour creatinine clearance at 11/2 years. RESULTS: High-density lipoprotein (HDL) cholesterol of the recipient < or =47 mg/dL was a risk factor for the functional (RR = 1.56; 95% CI, 0.978 to 2.497) and the morphological (RR = 2.75; 95% CI, 1.075 to 7.037) outcome of the graft, mainly in patients without acute rejection (RR = 2.03; 95% CI, 1.13 to 3.65, and RR = 4.67; 95% CI, 1.172 to 18.582, respectively). Interstitial accumulation of OxLDL was inversely associated with HDL cholesterol (R = -0.476, P = 0.019), and was associated with a higher density of tubulointerstitial macrophages (R = 0.656, P = 0.001) and a higher fractional interstitial volume at 11/2 years (P = 0.049). CONCLUSION: Decreased HDL cholesterol levels of the recipient adversely affect the outcome of renal allografts through the accumulation of OxLDL in the renal interstitium of the graft. Interstitial accumulation of OxLDL was associated with the presence of macrophages and the development of interstitial fibrosis.

Health status of Romanies (Gypsies) in the Slovak Republic and in the neighbouring countries.

Romanies belong to Indo-European race. The ethnography and anthropology locate their original home to Central Northern India. The highest concentration of Romanies in Europe is in the Balkan and Carpathian regions and they are the second most numerous minority in the Slovak Republic. The inner structure of Romanies shows clear marks former ancestry creation, which they brought from India. Their natural increase of population is 21-33 per mile, but their reproductive health is worse than in majority of Slovak population. Among Romany children there is generally a higher prevalence of infectious diseases, injuries, poisoning and burns caused by environmental hazards, to which they are often exposed. Total premature mortality in the Romanies are probably three times higher than in the total Slovak population. The main causality of a bad health status consists in long-term bad economical situation, low educational level and incorrect lifestyle of the Romany minority. Western authors and politicians claim that at the beginning of 21st Century it is not conceivable for European governments to ignore health needs of a great number of their citizens. The aim of this review is to react to this notice with an analysis of present situation and with presentation of data of our epidemiological investigation on health status, nutrition and lifestyle of Romanies. (Fig. 4, Ref. 35.)