Biomedical subjects

Ioannis Griveas

Publications and source records attributed to Ioannis Griveas.

9 recordsLinked to original sources

PubMed2006

Comparison of blood and peritoneal lymphocytes from continuous ambulatory peritoneal dialysis patients, asymptomatic and with peritonitis.

OBJECTIVE: The purpose of this study was to compare the characteristics of the blood immunophenotype of CAPD patients with and without peritonitis and to compare the phenotypes of peripheral blood lymphocytes (PBL) and peritoneal lymphocytes (PL) in CAPD patients with peritonitis. METHODS: Fifty-seven CAPD patients (20 with peritonitis and 37 without peritonitis) were recruited in the study (mean age 66,88 +/- 13,48, male/ female 16/21). Lymphocyte subsets (CD2+, CD3+, CD3+/4+, CD3+/8+, CD3-/16 + 56+, CD4/CD8 ratio) were quantitated by using monoclonal antibodies and dual-color flow cytometric analysis. With the above method we measured PBL in patients with and without peritonitis. In patients with peritonitis we also measured PL. RESULTS: CD2 were slightly decreased in patients with peritonitis. Those patients also had more intense CD3 + / CD4+ lymphopenia (p < 0.05) and larger expansion of NK cells (p < 0.05). Patients with peritonitis appeared to have a lower ratio of CD4/CD8 (p < 0.05). All the above results are shown to Table 2. Following the onset of peritonitis, a consistent finding in all patients was a significant increase in CD2 population of PL compared with PBL (85.71 +/- 9.20 versus 82.60 +/- 7.34, p < 0.05) as well as in CD3 population (77.01 +/- 13.09 versus 68.74 +/- 13.43, p < 0.05). An increased number of CD3/8 in PL compared with PBL (33.70 +/- 9.34 versus 27.98 +/- 10.77, p < 0.05) was also noted. CONCLUSIONS: In the present study, we found important immune activation in asymptomatic CAPD patients. The activation increases during peritonitis. The causes and the clinical consequences of chronic activation remain unknown.

Aged↗

PubMed2006

Biocompatibility study based on differential sequestration kinetics of CD14+CD16+ blood monocyte subsets with different dialyzers.

The immune defect in hemodialysis (HD) patients is associated with a monocyte dysfunction, including an increase in the production of proinflammatory cytokines. Blood membrane contact leads to an increase in cellular activation and sequestration into the capillary bed of the lung. The influence of the sequestration on the number of mature monocytes was studied by analyzing the fate of monocytes, particularly, the CD14+CD16+ subpopulation, during HD treatment. In thirty stable HD patients, the distinct cell populations were determined by differential blood counts and flow cytometry. Patients with diabetes or systemic vasculitis, those showing evidence of infectious complications or malignancy, or those taking immunosuppressive medications were excluded from the study. Cells from this study population were analyzed before the start, 30 min thereafter, and at the end of HD treatment, each time using a different dialyzer: hemophan, methylmethacrylate (PMMA), triacetate membrane, cuprophane/vitamin E, acrylonitrile, and sodium methallylsulfonate polymer (AN69). The CD14+CD16+ subset decreased at 30 min and remained suppressed for the course of dialysis. To examine whether currently used biocompatible membranes differ in their effect on the sequestration of monocyte subpopulations, temporal monocytic changes were comparatively analyzed during HD with a different dialyzer. The drop in the first 30 min until the end of HD treatment was significant (p<0.05), very uniform, and sharp in all patients, and was independent upon membrane type. The CD14+CD16+ monocyte subpopulation showed increased and longer margination from the blood circulation during HD. Given the fact that CD14+CD16+ monocytes represent a sensitive marker for inflammation or cellular activation, the depletion of these cells may offer an easily accessible parameter that is more sensitive than complement activation for biocompatibility studies on forthcoming, improved dialyzer membranes.

Aged↗

PubMed2005

Increase in serum magnesium level in haemodialysis patients receiving sevelamer hydrochloride.

BACKGROUND: Clinical studies have shown that sevelamer hydrochloride improves lipid profiles and attenuates the progression of the cardiovascular calcifications in haemodialysis patients. It is known that both of these properties are associated with increased magnesium levels. The effect of sevelamer on serum magnesium level is not well documented. The aim of this study was to determine the effects of sevelamer treatment on serum magnesium in haemodialysis patients and to assess the association of magnesium levels with lipid profiles and intact parathyroid hormone (iPTH). METHODS: Phosphate binders were discontinued during a two week washout period. Forty-seven patients, whose serum phosphate was greater than 6.0 mg/dl at the end of washout, received sevelamer hydrochloride for eight weeks. The patients were then washed off sevelamer for another two weeks. RESULTS: Mean serum phosphorus concentration declined from 7.5 +/- 1.3 to 6.4 +/- 1.2 mg/dl (P < 0.001), mean serum magnesium levels increased from 2.75 +/- 0.35 to 2.90 +/- 0.41 mg/dl (P < 0.001) and median serum iPTH levels decreased from 297 to 213 pg/ml (P=0.001) during the eight weeks of sevelamer treatment. After the two week post-treatment washout phosphorus levels increased to 7.3 +/- 1.3 mg/dl (P < 0.001), magnesium levels were reduced to 2.77 +/- 0.39 mg/dl (P < 0.001) and iPTH levels increased to 240 pg/ml (P=0.012). No change was observed in serum calcium levels during the sevelamer treatment period and the subsequent washout period. The mean decline in total and low density lipoprotein (LDL) cholesterol during sevelamer treatment was 16.3 and 28.3 (P < 0.001), respectively. The mean increase in high density lipoprotein (HDL) cholesterol and in apolipoprotein A1 was 2.9 +/- 5.8 mg/dl (P=0.004) and 6.8 +/- 11.1 mg/dl (P=0.001), respectively. Multivariate analysis showed that the rise in serum magnesium concentration significantly correlated with reductions in iPTH levels (r=-0.40, P=0.016), but did not have any significant correlation with the changes in lipid profiles. CONCLUSIONS: Our findings indicate that patients on haemodialysis receiving sevelamer have a significant increase in serum magnesium concentrations. This increase in serum magnesium is associated with reduction in iPTH levels. The changes in lipid profiles of these patients however are not related to changes in serum magnesium levels.

Female↗

PubMed2005

Cellular immunity and levels of parathyroid hormone in uremic patients receiving hemodialysis.

OBJECTIVE: The clinical relevance of altered lymphocyte function and the possible relation with uremic toxins, such as parathyroid hormone (PTH) is not well understood. We studied the changes in cellular immunity in patients in hemodialysis (HD) therapy and examined the relationship between T-lymphocyte function and plasma levels of PTH. PATIENTS AND METHODS: Thirty-four patients (14 male) were enrolled in this study (mean age: 63.20 +/- 10.01 years, M +/- SD, 12 h/week HD). Our study population was divided into two groups: 18 patients with increased levels of PTH and 16 patients with normal levels of PTH. Lymphocyte subsets (CD2+, CD3+, CD3+/4+, CD3+/8+, CD19+, CD3-/16+56+, CD4/CD8 ratio) were quantitated in both groups using monoclonal antibodies (Immunotech, Coulter) and flow cytometric analysis. Following analysis of variance (ANOVA) testing was performed to test differences between groups (SPSS version 10). RESULTS: A significant increase of CD2 was noticed in patients with increased levels of PTH (84.8 +/- 5.5 vs. 79.8 +/- 4, p<0.05). The CD3 population was also increased in patients with elevated PTH (72 +/- 8.6 vs. 68 +/- 9.2, p=NS). This group of patients had also significantly increased levels of CD3/8 (44.8 +/- 9.8 vs. 37.1 +/- 5.8, p<0.05). The CD4/CD8 ratio levels were higher in patients with elevated PTH compared with those who had normal PTH (2.2 +/- 1.5 vs. 1.5 +/- 0.8, p=NS). CONCLUSIONS: The elevated level of PTH seems to affect the lymphocyte function and is associated with changes in cellular immunity in the hemodialysis population. Our study is in progress in order to enlarge our study population and collect more data, which will lead us to more solid conclusions.

Biomarkers↗

PubMed2005

Comparative analysis of immunophenotypic abnormalities in cellular immunity of uremic patients undergoing either hemodialysis or continuous ambulatory peritoneal dialysis.

AIM: To investigate the abnormalities of cellular immune responses in patients on hemodialysis (HD) and in those on continuous ambulatory peritoneal dialysis (CAPD). PATIENTS AND METHODS: Forty-five (45) healthy volunteers, 34 patients on HD therapy, and 37 patients on CAPD were recruited for the present study. Lymphocyte subpopulations (CD2+, CD3+, CD3+/CD4+, CD3+/CD8+, CD3-/16+56+, CD19, and CD4/CD8) were determined by flow cytometry. RESULTS: Lymphopenia, decreased absolute counts, and altered percentage values of CD3+, CD3+/ 4+, and CD19+ subpopulations were found in both patient groups. The HD and CAPD patients showed increased percentages of natural killer cells (CD3-/16+56+) compared to controls but CD4+/CD8+ ratio showed no significant changes among uremic patients and controls. CONCLUSIONS: Replacement therapy may contribute to the quantitative alterations of immune subsets found in HD and CAPD patients compared to normal subjects. We speculate that these changes account, at least in part, for the immune dysregulation observed in patients with chronic renal failure. Analysis of lymphocyte subsets will help the research and the evaluation of the possible causes of immunodeficiency in uremic patients undergoing replacement therapy and will probably contribute to more efficient and preventive strategies.

Adult↗

PubMed2005

Relevance of procalcitonin levels in comparison to other markers of inflammation in hemodialysis patients.

PURPOSE: The objective of this study was to evaluate the diagnostic value of serum procalcitonin (PCT) in hemodialysis (HD) patients and its correlation to other traditional inflammatory markers. METHODS: We measured plasma PCT levels in 120 patients on maintenance HD. PCT levels were compared with C-reactive protein (CRP), interleukin-6 (IL-6), prealbumin, and albumin. We also examined the above parameters subgroups, especially in diabetics and the elderly. Relations between parameters were studied by Spearman's correlation. RESULTS: PCT concentrations were higher than the upper normal limit of 0.5 ng/ mL in 38% of the patients. All patients with increased CRP had PCT concentrations higher than the upper normal limit. Plasma CRP concentrations were positively correlated to IL-6 (r = 0.304). Prealbumin was negatively correlated with CRP (r = 0.259) and with IL-6 (r = 0.388). CONCLUSIONS: The combination of elevated IL-6 and CRP levels was associated with an altered nutritional status. The concomitant elevations in PCT, CRP, and IL-6 could be more sensitive in the evaluation of inflammation.

Aged↗

PubMed2004

Therapeutic apheresis of immune diseases in nephrology department.

OBJECTIVE: The clinical efficacy of therapeutic apheresis is still controversial. We undertook a retrospective review of apheresis treatment to ascertain its safety and efficacy. METHODS: We reviewed 31 patients (13 male, 18 female). Plasmapheresis was performed on 7 patients with hematologic disorders, 5 patients with neurologic disorders, 6 patients with systemic diseases, and 3 patients with Lyell syndrome. Immunoadsorption onto protein A sepharose was evaluated as rescue therapy in 7 patients. Low-density lipoprotein (LDL) apheresis was performed on 3 patients. RESULTS: There were five mortalities due to serious complications of their primary disease. Most complications were mild such as hypotension and hypocalcemia. Two patients who received LDL apheresis had severe anaphylactic reactions. Apheresis was effective in the remaining 24 patients. CONCLUSIONS: The therapeutic apheresis consists of a continuously improving therapeutic method for diseases with high mortality and morbidity, especially in cases with poor outcome by using current medications.

Adult↗

PubMed2004

Lymphocytes subsets in the course of continuous ambulatory peritoneal dialysis (CAPD).

BACKGROUND: We studied lymphocyte subset counts in comparison with normal subjects in order to clarify the abnormalities of cellular immune responses in uremic patients undergoing continuous ambulatory peritoneal dialysis (CAPD). METHODS: The study included 37 CAPD patients and 45 normal individuals, as the control group. For the study, CAPD patients were divided into four groups depending on duration of replacement therapy. Group I consisted of patients treated for 0-6 months (n=6), group II for 6-12 months (n=6), group III for 13-24 months (n=16), and group IV for more than 25 months (n=9). Flow cytometry was used for estimation of lymphocyte subsets (determination of CD2, CD3, CD3+/CD4+, CD3+/CD8+, CD3-/16+56+, CD19, CD4/CD8). RESULTS: Our patients started CAPD with decreased lymphocyte subset counts, slightly above the normal range (excluding CD3 -/16+56+, CD2). After 6 months of CAPD therapy, an increase in CD4/CD8 ratio was observed and all examined lymphocyte subset counts decreased (excluding CD2). In patients on CAPD for more than 25 months, CD3+/CD4+, CD19 counts were below the normal range, CD3 -/16+56+ exceeded the upper limit of normal range and at the same time mean total lymphocyte count (TLC) was maintained in the normal range. CONCLUSIONS: We recommend lymphocyte subset determinations for detection of immune abnormalities in the course of CAPD treatment.

Age Factors↗

PubMed2004

Immunoadsorption in lupus myocarditis.

Reduction of pathological autoantibodies may be useful in the treatment of systemic lupus erythematosus (SLE). On the other hand clinically manifested myocarditis in SLE, though uncommon, may be life-threatening and its pathogenesis has been ascribed to autoimmunity. The aim of this study is to present a rare case of a patient with severe lupus myocarditis, where immunoadsorption (IA) was evaluated as rescue therapy. A case of SLE with initial manifestation of myocarditis is reported in a 29-year-old male who presented with arthritis, fever, lymphadenopathy, joint swelling and morning stiffness. Laboratory evaluation revealed increased antinuclear antibody (ANA), slightly decreased complement and positive anticoagulant panel. From the above clinical and laboratory features, criteria of SLE seemed applicable. During his hospitalization, the patient developed pericardial effusion and cardiogenic shock. Although pericardiotomy was performed and was treated with immunosuppressive agents, plasmapheresis and supported with current medications, his clinical condition remained critical with an ejection fraction of 20%. At this point it was decided to receive IA onto staphylococcal protein A. After 6 sessions with IA and concomitant immunosuppression, the patient responded well, his condition improved and was dismissed with an ejection fraction of 50%. Fulminant lupus myocarditis is a severe and rare situation lacking a satisfying specific therapy available today. In our presented case, IA in addition to immunosuppressive therapy was beneficial. Considering the benefits of our case and the current knowledge, it might be useful to clarify the open question in scale pilot studies.

Adult↗