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Background: During haemodialysis (HD) treatment, increase of platelet (PLT) activation and induction of procoagulant activity is demonstrated. Although the role of the endothelium and its direct interaction with coagulation and homeostasis is known, it is not elucidated how PLT activation markers and activation of coagulation coincide with markers of endothelial integrity during HD treatment. In the present study uraemia and HD induced changes, with particular emphasis on PLT granules depletion, activation of coagulation and endothelial integrity were investigated. Methods: To detect depletion of PLT granules, peripheral blood slide smears were screened by light microscopy for qualitative evaluation of PLT granule containing cytoplasm, as indicated by its granules staining density. Activation of coagulation was investigated by establishement of thrombin-antithrombin (TAT) and fibrinogen concentrations. To evaluate endothelial integrity proendothelin (proET-1) plasma concentrations were established. Results: Results of our study demonstrate that proET-1 plasma concentrations were obviously increased in the subjects' group with end-stage chronic kidney disease (CKD) and renal failure if compared with a group of apparently healthy subjects. The amount of depleted PLT granules was obviously increased in the subjects' group with end-stage CKD if compared with the group with renal failure. Mean plasma concentrations of TAT and fibrinogen revealed results within the reference range. Conclusions: It is demonstrated that uraemia is associated with endothelial damage and aberrations in PLT granules morphology in subjects with HD treatment. We hypothesize that increased proET-1 concentrations reflect ongoing stress on endothelial cells amongst others due to uraemia. Biomarkers like proET-1 and aberrations in PLT granules morphology assist in the early detection of procoagulant activity of the endothelium. [ABSTRACT FROM AUTHOR]

Introduction. Patients with community-acquired pneumonia (CAP) often exhibit a declining hemoglobin (Hb) concentration. During inflammation pro-inflammatory cytokines and cells of the reticuloendothelial system induce disturbances in iron homeostasis. In this study inflammation markers and hepcidin-25 concentrations were monitored together with short-term alterations in reticulocyte hemoglobinization (RET-He). Methods. A total of 25 patients with CAP participated in the study. The assay for serum hepcidin-25 is based on a combination of weak cation exchange chromatography and time-of-flight mass spectrometry. Results. At hospital admission serum hepcidin-25 concentrations (14.6 ± 6.9 nMol/L, mean ± SD) were established in the upper level of the reference range (0.5-13.9 nMol/L). Results for C-reactive protein (CRP) and Interleukin-6 (IL-6) were obviously increased compared to the reference ranges. From admission until day 14 hepcidin-25, CRP and IL-6 steadily decreased towards the reference ranges. Hb concentrations declined from admission until day 4 from 8.1 ± 1.0 mMol/L to 7.4 ± 0.9 mMol/L. At admission Ret-He results were within the lower region of the reference range (1900-2300aMol) and results demonstrated a decline during admission from 1931 ± 241 aMol until 1845 ± 199 aMol (NS) at day 4. From a minimum Ret-He value at day 4 results increased towards 2129 ± 136 aMol at day14. Conclusion. A transient increase of cytokine-stimulated serum hepcidin-25 in combination with a temporary decrease of Hb and Ret-He is demonstrated in patients with CAP. Our results support the hypothesis that hepcidin-25 induces transient impairment of reticulocyte hemoglobin content (Ret-He). [ABSTRACT FROM AUTHOR]

For many years, application of RBC indices has been recommended for discriminating between subjects with iron deficiency from those with thalassemia. However, application of the algorithms resulted in only 30% to 40% of subjects being appropriately classified. The aim of the study was to establish the efficacy of algorithms for anemia screening including new hematologic parameters such as percentage of hypochromic and microcytic RBCs and hemoglobin content of reticulocytes. Subjects with iron deficiency anemia (IDA) (n = 142) and subjects with β-thalassemia (n = 34) were enrolled in a European multicenter study. Apparently healthy subjects were used as a reference group (n = 309). Hemocytometric investigations were performed on a Sysmex XE5000 hematology analyzer. The algorithms for IDA discrimination yielded results for area under the curve, sensitivity, specificity, and positive and negative predictive values of 0.88, 79%, 97%, 74%, and 98%, respectively. The algorithms for β-thalassemia discrimination revealed similar results (0. 86, 74%, 98%, 75%, and 99%, respectively). We conclude that the advanced algorithms, derived from extended RBC parameters provided by the Sysmex XE5000 analyzer, are useful as laboratory anemia screening devices. [ABSTRACT FROM AUTHOR]

Patients with mild-to-chronic kidney disease (CKD) exhibit a variety of haemostatic disorders, ranging from an increased clotting tendency and reductions in the levels of natural inhibitors of coagulation to defective fibrinolysis. In addition, platelet (PLT) abnormalities are common. In this minireview, we report on aspects of haemodialysis (HD)-induced PLT activation. It is demonstrated that PLTs from HD patients are exhausted due to repeated stimulation of HD treatment and recurrent release of PLT degranulation products. During HD, additional aberrations of the haemostatic process occur. Besides deviations of coagulation and fibrinolysis, PLT activation and a reduction in their granule content have been observed during HD treatment. As HD treatment is carried out three times per week, month after month, chronic HD patients may suffer persistently from coagulation defects and PLT disorders on top of the alterations induced by the uraemic state itself. PLT activation occurs together with thrombin and fibrin generation. However, macro fibrin depositions in clot devices are not demonstrated, microaggregates occur not only in the extracorporeal circuit (ECC) but are also present in the blood circulation. As vascular access thrombosis is a frequent complication in patients with HD treatment, it is believed that hypercoagulability could result from vascular changes combined with PLTs and activation of coagulation factors.

Although a mild degree of anemia is common in the third trimester of pregnancy, it remains a challenge to establish whether a decrease in hemoglobin (Hb) concentration is physiological or pathological. The World Health Organization suggested a Hb concentration of 110 g/L to discriminate anemia. Several European investigators recommended Hb cut-off values of between 101-110 g/L. The aim of this study was to establish short-term effects of iron supplementation on the hemoglobin content of reticulocytes (Ret-He) and red blood cells (RBC-He) in case of suspected iron deficient erythropoiesis (IDE) in the third trimester of pregnancy. Twenty-five subjects with suspected IDE during pregnancy (Hb ≤110g/L, Ret-He <29.6 pg, zinc protoporphyrin >75 mol/mol hem) participated in the study. After iron supplementation, reticulocyte counts increased from 0.061±0.015×10(12)/L to 0.079±0.026×10(12)/L and Ret-He increased from 23.6±2.8 pg to 28.3±2.6 pg (P=<0.001). RBC-He increased from 26.9±1.9 pg to 27.4±1.8 pg (not significant, NS) and Ret-He/RBC-He ratio increased from 0.97±0.06 towards 1.07±0.05 (P=<0.001). Hb concentrations demonstrated an obvious increase from 105±6 g/L towards 115±5 g/L (P≤0.001) after supplementation. An obvious increase in RBC distribution width was observed from 45.0±3.6 fL towards 52.3±7.0 fL (P≤0.001). We recommend that Ret-He and Ret-He/RBC-He ratio be integrated into the protocols for anemia screening and for monitoring effects of iron supplementation during pregnancy. In particular, the parameters should be considered in subjects with Hb results in the controversial range of 101-108 g/L.

During haemodialysis (HD), platelets (PLTs) are activated and release granule contents. As HD treatment occurs three times a week, it has been demonstrated that PLTs are exhausted due to the repetitive character of the treatment. To identify PLT depletion morphologically, PLT evaluation was performed by light microscopy and electron microscopy (EM) in a chronic HD subject and a healthy reference subject. Blood samples were taken before the start of HD treatment for measurement of PLT count, PLT volume and size parameters. Blood smears were screened by light microscopy for qualitative evaluation of PLT granule containing cytoplasm, as indicated by its staining density. Morphological PLT parameters of surface area and size of dense bodies were assessed by EM. Data were compared with results of a group of 20 chronic HD subjects and a group of 20 healthy reference subjects. With respect to the percentage of PLTs with appropriate staining density (>75%), light microscopic evaluation showed that this value (9%) was within the range of a group of chronic HD subjects, but considerably below the reference range (70%). EM evaluation revealed an average PLT surface area and dense bodies area of respectively 42% and 31%, if the healthy reference subject was set on 100%. PLTs from a chronic HD subject are considerably smaller and substantially less granular than PLTs from a healthy reference subject. These findings support the hypothesis of PLT depletion in chronic HD subjects due to frequent PLT activation and/or increased urea concentrations.

Background: Although platelet (PLT) activation and degranulation are well-known phenomena during hemodialysis (HD), controversies still exist about their nature and origin., Methods: PLT characteristics [PLT numbers, mean PLT volume (MPV), PLT distribution width (PDW), PLT large cell ratio (p-LCR), immature PLT fraction] and activation status [CD62p expression, platelet factor 4 (PF4) and beta-thromboglobulin (BTG) plasma levels] were estimated in 19 patients before and during HD. Blood was sampled from both the afferent and efferent lines. Additionally, the influence of low-molecular-weight heparin (LMWH) on PF4 and BTG concentrations was analyzed., Results: CD62p expression increased in the extracorporeal circuit (ECC) in the first 30 min. Simultaneously, PLT numbers dropped markedly within the ECC. MPV, PDW and p-LCR decreased over time. Like CD62p expression, BTG reached peak values at t30, was exclusively released within the ECC and was not influenced by the application of LMWH. In contrast, PF4 was significantly released outside the ECC in response to LMWH., Conclusions: PLTs are predominantly activated within the ECC and not on a remote distance. PLTs stick to the ECC, particularly after first passage. BTG is an appropriate marker for HD-induced PLT degranulation, whereas PF4 originates from both activated PLTs and LMWH-induced detachment from the endothelium. PLTs are not exhausted due to the repetitive stimulation of clinical HD. Hence, dialysis modalities with longer duration or greater frequency may be associated with a less beneficial PLT activation profile, which may counteract their clinical benefits., (Copyright 2009 S. Karger AG, Basel.)

Background: The etiology of intradialytic hemodynamic instability is multifactorial. Of the various factors involved, a rise in core temperature seems to be crucial. In this respect, the bioincompatibility of hemodialysis (HD) treatment might play an important role. The application of cool dialysate reduces the number of periods of intradialytic hypotension (IDH) considerably. In rats, roller pump perfusion caused hypotension by shear stress induced platelet aggregation and subsequent serotonin release. During clinical HD, citrate anticoagulation abolished platelet activation almost completely. Hence, citrate anticoagulation might reduce IDH, whereas the beneficial effect of cool dialysate might be partly explained by reduced platelet activation., Methods: In the present study, blood pressure, IDH episodes, platelet activation, platelet aggregation, and serotonin release were studied crossover in 10 patients during HD with dalteparin anticoagulation at normal and low dialysate temperatures and during HD with citrate., Results: Citrate strongly reduced platelet activation, but did not improve IDH. The blood pressure was best preserved during cool-temperature HD, despite manifest platelet activation. Platelet activation was not accompanied by a rise in the plasma serotonin concentration., Conclusions: Three major conclusions can be drawn: (1) it is unlikely that platelet activation and subsequent serotonin release underlie IDH in the clinical situation; (2) the protective effects of cool dialysate on IDH appear to be independent of HD-induced platelet activation, and (3) extrapolating results from rat experiments to the human situation requires uppermost prudence., (Copyright 2007 S. Karger AG, Basel.)

Microcytic erythropoiesis in case of anemia is frequently due to iron deficiency or may be due to alpha- and beta- thalassemia trait as a result of increased activity of erythropoiesis. The aim of the present study was to evaluate alterations with regard to the degree of hemoglobinization in reticulocytes in comparison with mature erythrocytes. Iron availability in subjects with anemia resulting from iron deficiency and alpha- or beta- thalassemia was studied by application of conventional as well hemocytometric parameters that have recently become available. Participants of the study were reference subjects (n=75), subjects with iron deficiency anemia (IDA, n=52) and alpha- (n=26) or beta-thalassemia trait (n=24). If compared with the reference group obviously increased RBC counts together with decreased values for RDW-sd and MCHC were established in case of alpha- and beta- thalassemia subjects. Deviations were demonstrated to be more pronounced in case of beta- thalassemia. Accelerated erythropoiesis in the case of subjects with IDA and beta-thalassemia is manifested by detection of increased results for immature reticulocyte counts. In particular in case of beta- thalassemia, elevated reticulocyte counts combined with slightly increased values for ZPP/heme ratio reflect increased activity of erythropoiesis. In the case of subjects with beta-thalassemia serum transferrin concentrations revealed slightly decreased results, whereas serum ferritin and iron concentrations demonstrated a tendency towards higher values if compared with the group of reference subjects. At a definitive MCV level, the hemoglobin content of reticulocytes is decreased in the case of IDA if compared with the alpha- or beta- thalassemia trait. For the ratio of hemoglobin content of reticulocytes and erythrocytes, obviously decreased results are demonstrated in the case of subjects with iron deficiency anemia (1.02 +/- 0.08, mean +/- SD) and in the case of beta-thalassemia (1.06 +/- 0.04) if compared with the group of reference subjects (1.11 +/- 0.02) and a-thalassemia (1.11 +/- 0.07). Evaluation of the hemoglobinization state should be performed by means of pattern recognition in concordance with characteristic profiles for parameters reflecting the actual iron state. In case of therapy the result of intervention can be appropriately monitored by longitudinal follow-up.

In hemodialysis subjects correction of anemia is facilitated by combined supplementation of intravenous iron and recombinant human erythropoietin. Reticulocyte hemoglobin content (RET-He) is considered to be an actual indicator reflecting functional iron availability for erythropoiesis. In the present study, interdependence between biochemical analytes reflecting iron status and hemocytometric parameters indicating the degree of hemoglobinization of reticulocytes and red blood cells, respectively, is established. Participants of the study were reference subjects (n=75), subjects with iron deficiency anemia (n=52), subjects with uremia (n=19) and subjects undergoing hemodialysis treatment (n=43). If compared with the reference subjects the results for RBC counts and MCHC are statistically significantly decreased in case of subjects with hemodialysis and uremia, whereas increased results are established with regard to RDW-sd values. Significantly increased results for absolute reticulocyte counts and immature reticulocyte fractions (IRF) are also observed in case of subjects with hemodialysis and uremia. Slightly increased values for the ZPP/heme ratio in combination with elevated reticulocyte count reflect increased activity of erythropoiesis. At a definite MCV value, decreased levels for the hemoglobin content of reticulocytes (RET-He) and hemoglobin content of red blood cells (RBC-He) are observed in case of subjects treated with hemodialysis and in subjects with uremia if compared with identical MCV values of the group of reference subjects. For the ratio of RET-He and RBC-He obviously decreased results are demonstrated in case of subjects with iron deficiency anemia (1.02 +/- 0.08, mean +/- SD), hemodialysis (1.05 +/- 0.05) and uremia (1.02 +/- 0.10) if compared with the group of reference subjects (1.11 +/- 0.02). From the combined interpretation of the MCV values within the reference range and decreased values for RET-He and RET-He/RBC-He ratios, respectively, a decreased degree of hemoglobinization is concluded in the case of subjects with hemodialysis or uremia. The conclusion implicating the presumption of reduced functional availability of iron for hemoglobin synthesis is supported by the detection of increased results for sTfR concentrations and ZPP/heme ratios.

In a longitudinal follow-up study the effect of pharmaceutical supplementation of nutrients (folate, vitamin B12, B6, B1, C, iron and proteins) was established in 25 psychogeriatric patients (subject group). A reference group of 30 apparently healthy elderly subjects was used for comparison and statistical evaluation. At the time of hospitalization percentages concerning the incidence of decreased serum concentrations reflecting an inappropriate nutrient state in the subject group amounted to 28% for vitamin B12, 20% for folate, 36% for iron, 12% for transferrin and 56% for albumin concentrations. Increased plasma concentrations of homocysteine combined with decreased folate concentrations were found in 16% of the psychogeriatric patients. If compared with the initial results at admission, after three weeks of nutrient supplementation the vitamin B12 and folate serum concentrations were increased. Results for serum iron concentrations remained below the reference range interval in 5 of the 25 subjects reflecting iron deficiency. Initially decreased serum transferrin concentrations did not return to the reference range. Serum albumin levels still further decreased after admission to the hospital, resulting after three weeks in albumin concentrations below the reference range for 68% of the subjects. It is concluded that supplementation of folate and vitamin B12 lowered homocysteine plasma concentrations successfully. Supplementation of protein nutrients is not appropriate in order to restore disturbances of protein metabolism. Persisting low concentrations of proteins in serum are indicative of irreversible decreased synthesis.

Background: In chronic hemodialysis (HD) patients, the repetitive induction of the acute phase response (APR) may induce a chronic micro-inflammatory state, leading to various long-term complications., Methods: The present prospective study was designed to assess the alterations in the APR in 74 patients who were randomized to HD with a high-flux polysulfone (PS; F 60S), a super-flux PS (F 500S), or a super-flux cellulosic tri-acetate (CTA and CTA with filtered dialysate, CTA(f)) dialyzer. Blood samples collected at the start of the study and after twelve weeks were analyzed for interleukin-6 (IL-6) and C-reactive protein (CRP). In addition to the microbiological quality of the dialysate, the appearance of a "clinical event" was assessed., Results: At baseline, mean IL-6 levels were within the reference range whereas mean CRP levels were slightly elevated. Mean values did not change after 12 weeks of HD with either modality. After subdividing the patients in quartiles with increasing change in plasma CRP, 23.0% of the patients showed a change of more than 8.0 mg/L. In a multiple regression analysis, CRP levels appeared to be independent of the degree of dialysate contamination, the material and the flux characteristics of the devices. In fact, the variable "clinical events" was the only significant predictor of the plasma CRP levels (P < 0.001)., Conclusions: Based on these results, both PS and CTA super-flux dialyzers appear safe for clinical use. Whether changes in CRP values, which are associated with intercurrent clinical events, influence the long-term prognosis of chronic HD patients remains to be established.