Hematocrit Measurements Research Articles

Comments on Lundby et al.'s “Testing for recombinant human erythropoietin in urine: problems associated with current anti-doping testing”

to the editor: Ideally, anti-doping testing is designed to ensure fair competition and prevent athletes' harm from unfair practices. While the former issue is questionable, since fairness in sports is mostly a chimera, the latter is foremost and theoretically viable ([1][1]–[3][2]). The recent

Multigate Doppler Measurements of Ultrasonic Attenuation and Blood Hematocrit in Human Arteries

A clinically applicable method for noninvasive measurement of hematocrit based on 20 MHz multigate Doppler ultrasound was developed. The ultrasound attenuation coefficient in blood is obtained by measuring the power of the signal coming from gates at different depths. A robust averaging method is introduced, which provides stable and repeatable results by using the echo signals from all depths inside the vessel. In vitro measurements have been done on porcine blood with hematocrit ranging from 3.0% to 65.0%. Steady and pulsatile flow conditions have been simulated using a peristaltic pump. The attenuation coefficient indicated the linear relation to hematocrit. The resulting correlation coefficient was R = 0.999 for the continuous blood flow and R = 0.992 for pulsatile flow. In vivo measurements have been performed in the brachial artery in 43 patients with hematocrit in the range of 32.0% to 49.3%. The mean absolute error has been 3.24% with a standard deviation of 3.72%. (E-mail: wsecom@ippt.gov.pl)

Recovery of hemoglobin mass after blood donation

Blood donation plays an important role in every health care system. Measurement of hemoglobin (Hb) concentration or hematocrit to assess hematologic recovery after donation may not adequately reflect the true amount of blood as they are affected by plasma volume fluctuations. Instead, total Hb mass (tHb) is the variable of choice and can be determined in routine clinical practice. Therefore, the purpose was to investigate the recovery of tHb after standard blood donation. The optimized CO rebreathing method was used for evaluation of tHb before and after 1-unit (erythrocyte concentrate) standard blood donation in 29 male volunteers (30 +/- 10 years, 181 +/- 7 cm, 76.6 +/- 11.2 kg). Subsequently, tHb measurements were performed in regular intervals until one of two termination criteria was met. After donation of approximately 550 mL of whole blood, the lost amount of tHb of 75 +/- 15 g (8.8 +/- 1.9%) was recovered after a mean of 36 +/- 11 days (range, 20-59 days). The results of this study confirm the minimal, recommended donation intervals (56 days for men) as adequate when, for the first time, judged upon by tHb as a direct marker of hematologic recovery.

Electronegative LDL and Lipid Abnormalities in Patients Undergoing Hemodialysis and Peritoneal Dialysis

Background: Oxidative modification of low-density lipoprotein (LDL) has been demonstrated in patients with end-stage renal disease, where it is associated with oxidative stress and plays a key role in the pathogenesis of atherosclerosis. In this context, the generation of minimally oxidized LDL, also called electronegative LDL [LDL(–)], has been associated with active disease, and is a detectable sign of atherogenic tendencies. The purpose of this study was to evaluate serum LDL(–) levels and anti-LDL(–) IgG autoantibodies in end-stage renal disease patients on dialysis, comparing patients on hemodialysis (HD), peritoneal dialysis (PD) and a control group. In addition, the serum lipid profile, nutritional status, biochemical data and parameters of mineral metabolism were also evaluated. Methods: The serum levels of LDL(–) and anti-LDL(–) IgG autoantibodies were measured in 25 patients undergoing HD and 11 patients undergoing PD at the Centro Integrado de Nefrologia, Rio de Janeiro, Brazil. Ten healthy subjects served as a control group. Serum levels of albumin, total cholesterol, triglycerides and lipoproteins were measured. Calculations of subjects’ body mass index and measurements of waist circumference, triceps skin fold and arm muscle area were performed. Measurements of hematocrit, serum blood urea nitrogen, creatinine, parathyroid hormone, phosphorus and calcium were taken. Results: Levels of LDL(–) were higher in HD patients (575.6 ± 233.1 µg/ml) as compared to PD patients (223.4 ± 117.5 µg/ml, p < 0.05), which in turn were higher than in the control group (54.9 ± 33.3 µg/ml, p < 0.01). The anti-LDL(–) IgG autoantibodies were increased in controls (0.36 ± 0.09 µg/ml) as compared to PD (0.28 ± 0.12 µg/ml, p < 0.001) and HD patients (0.2 ± 0.1 µg/ml, p < 0.001). The mean values of total cholesterol and LDL were considered high in the PD group, whereas the mean triceps skin fold was significantly lower in the HD group. Conclusion: Levels of LDL(–) are higher in renal patients on dialysis than in normal individuals, and are reciprocally related to IgG autoantibodies. LDL(–) may be a useful marker of oxidative stress, and this study suggests that HD patients are more susceptible to cardiovascular risk due to this condition. Moreover, autoantibodies reactive to LDL(–) may have protective effects in chronic kidney disease.

Nutritional Status and its Correlates in Equatorial Guinean Preschool Children: Results from a Nationally Representative Survey

In Equatorial Guinea, as a result of the recent growth of the oil industry, there is an opportunity to address important public health problems through public and private initiatives. To propose effective nutrition and public health strategies, it is important first to have reliable information on the nutritional status of the population and the underlying factors affecting it. To assess the nutritional status and the prevalence of anemia among Equatoguinean children in a nationally representative sample and to identify the risk factors associated with the nutritional problems detected. The study was a cross-sectional survey using a multistaged, stratified, cluster-selected sample. The survey included a sociodemographic, health, and dietary questionnaire and measurement of hematocrit and anthropometric features, from which nutritional indicators based on the National Center for Health Statistics (NCHS) reference and the World Health Organization (WHO) standards were calculated. Logistic regression models were used for the multivariate analysis. A total of 552 children aged 0 to 60 months were surveyed. The overall prevalence of stunting (< -2 height-for-age z-scores [HAZ]) was 29.7% based on the NCHS reference and 35.2% based on WHO standards; the risk factors associated with stunting were age (p < .0001), low socioeconomic status (p = .01), and fishing by a member of the household (p = .003) The prevalence of mild anemia (hemoglobin < 110 g/L) was 69.3%, and that of moderate or severe anemia (hemoglobin < 80 g/L) was 8.3%. The only significant risk factor associated with moderate to severe anemia was low household socioeducational level (p = .01). Stunting and anemia are public health problems in Equatorial Guinea. Integrated strategies, including fighting poverty and improving maternal education, should be undertaken.

Effect of Hemolysis and Free Hemoglobin on Optical Hematocrit Measurements in the Extracorporeal Circulation

Clinically significant hemolysis is a rare but serious problem in dialysis. Because hemolysis affects red blood cell count and optical density of plasma it has been speculated whether techniques used for online blood volume monitoring would be useful to detect hemolysis. In this study the influence of free hemoglobin on hematocrit and relative blood volume changes measured by optical means (CritLine, HemaMetrics, Kaysville, UT) were examined using an in vitro model with bovine blood. Free hemoglobin solutions were added in steps to circulating whole blood at baseline hematocrits covering a range from 30% to 60% and at blood flows of approximately 200 and 400 ml/min. The free hemoglobin concentration reached was in the range of 2 to 3 g/dl. The presence of free hemoglobin led to a relative increase in hematocrit in the range of 0.3% per 0.1 g of free hemoglobin per dl (+3% dl/g). As an increase in hematocrit is interpreted as a decrease in blood volume, this change referred to an apparent decrease in relative blood volume in the same order of magnitude (-3% dl/g). Effects were more pronounced at low baseline hematocrit. Thus, although optical hematocrit readings are affected by the presence of free hemoglobin the changes at levels associated with clinical symptoms appear to be too small to be accurately detected in the in vivo situation where the hematocrit and the resulting optical signal is affected by various physiological processes and therefore much noisier.

The effects of fin rot disease and sampling method on blood chemistry and hematocrit measurements of winter flounder, Pseudopleuronectes americanus from New Haven Harbor (1987–1990)

Winter flounder from New Haven, Connecticut were evaluated for fin rot disease. Blood samples collected from healthy and diseased fish were used to measure bilirubin, calcium, hematocrit, inorganic phosphorus, osmolality, and total protein. Blood measurements were significantly affected by the presence of fin rot disease and by sampling mode (bled immediately or after 18 h). A reduction in blood chemistry values was associated with fin rot disease. Logistic regression modeling was used to identify explanatory variables contributing to the fin rot outcome in winter flounder. Blood constituent levels were higher in fish bled immediately versus 18 h post-capture, especially among fish without fin rot, suggesting that a waiting period is necessary for blood values to stabilize following initial sampling stress. This study presents evidence that winter flounder blood chemistry and hematocrit measurements are affected by fin rot disease.

The Physician Quality Reporting Initiative: A Practical Approach to Implementing Quality Reporting

The Physician Quality Reporting Initiative (PQRI) is a voluntary program in which Medicare encourages eligible physicians in the United States to report on specific quality measures. This article is a case study of the implementation of PQRI reporting by Kidney Associates, a nephrology practice in Houston, TX. After reviewing and discussing 74 potential measures, the group narrowed the selection to 5 and chose 1 office measure and 2 dialysis measures. PQRI reporting was established through an Encounter Note template that forced a required entry for whether a patient was diabetic. For each diabetic, blood pressures were entered in the template and appropriate G-codes were created, which were then selected and linked with the diabetes International Classification of Diseases, Ninth Revision code and electronically submitted for billing. The dialysis measures were automatically selected from the urea reduction rate and hematocrit (hemoglobin x 3) measures that were received for each patient on a regular basis from a large dialysis chain. Software was developed to parse these data, evaluate them, and generate the appropriate G-codes. At the end of the billing cycle, these data were exported through a standard spreadsheet formatting along with the billing G codes, and claims were submitted. The system was cost-effective to implement, required minimal education, and achieved 100% cooperation through feedback education and rapid correction of systems issues. Kidney Associates was able to show that PQRI reporting is easy to implement with minimal expense and staff labor. Sharing these methods with other practices should facilitate the implementation of efficient reporting systems.

The Newly Identified Hypertensive Patient: Cost‐Effective Laboratory Investigation

The Newly Identified Hypertensive Patient: Cost‐Effective Laboratory Investigation

Acute Angle Closure Glaucoma Presented with Nausea and Epigastric Pain

A 78-year-old woman was admitted to our department with nausea, vomiting, epigastric pain, and intense headache of the left side of 1 day duration. She had suffered from diabetes mellitus for the last 7 years and was being treated with a combination of metoformin (850 mg twice daily) and glimepiride (1 mg/day). In addition, for the last 5 years she was being treated for atrial fibrillation with acenocoumarol 1 mg/day. The patient also suffered from lumbar pain due to osteoarthritis and was being treated with a combination of paracetamol plus orphenadrine citrate (Norgesic) (450 + 35 mg per day) for the last 10 days. On admission, the patient was afebrile and the clinical examination revealed obesity, high arterial blood pressure (170/95 mmHg), and epigastric pain without clinical signs of peritonitis. Her left eye was red, and the pupil was more dilated and less reactive to light compared to the right eye. Laboratory findings included a hematocrit measurement of 44.5%, WBC at 8,900/mm, C-reactive protein of 4 mg/l, and total bilirubin at 1.3 mg/dl (direct 0.5 mg/dl). An ultrasound of the upper abdomen was without abnormal findings. A CT scan of the head was normal. Antiemetics and proton pump inhibitors were initiated, and with the diagnosis of possible conjunctivitis, a tobramycin eye ointment was given. The next day, the patient’s nausea had improved, but her headache had worsened and she reported a blurred vision from her left eye and photophobia. After reevaluation of her history and clinical findings, a digital tonometer was used which revealed an opening pressure of 62 mmHg on the left and 32 mmHg on the right eye. The diagnosis of acute angle closure glaucoma (AACG) was made, treatment was immediately started (eye drops of pilocarpine 2% and timolol 0.5%, acetazolamide 250 mg per os, and mannitol 1.0 mg/kg IV), and the patient was transferred to the ophthalmology department for further evaluation and management. AACG is an acute increased pressure in the front chamber (anterior chamber) of the eye due to sudden blockage of the normal circulation of fluid within the eye [1]. The high intraocular pressure can damage the optic nerve and lead to blindness. It is more common in elderly people and women, and is considered an emergency because vision loss can occur within hours of the onset of the symptoms [2]. Prompt diagnosis needs high index of suspicion, and it is based on topical symptoms (ocular pain, redness, blurred vision with coloured halos) and clinical examination (dilated and fixed pupil) [1]. These findings must be differentiated from other ocular diseases such as keratitis and conjunctivitis. In our case, unfortunately, the initial findings were attributed to conjunctivitis. In addition, as was seen in our patient, there are systemic symptoms as well (intense headache, nausea, vomiting, abdominal pain), which may be so severe that patients are misdiagnosed as having a neurologic or gastrointestinal disease [2–4]. Another important issue is the patient’s recent medications because several classes of drugs, including anticholinergic agents, tricyclic antidepressants, and SSRIs can precipitate AACG [5]. Our patient had no known previous history of glaucoma, but we believe that orphenadrine citrate was the provocative agent. Orphenadrine is a muscle relaxant, which is extensively used in painful muscular conditions [6]. It is a well tolerated drug, There are no conflicts of interest. All the authors have read and approved the submitted manuscript. The study complies with current ethical considerations.

Elevated Risk of Thrombosis in Neonates Undergoing Initial Palliative Cardiac Surgery

Thrombotic events cause significant morbidity and mortality in children who undergo surgery for complex congenital cardiac disease. We prospectively evaluated the incidence of thrombosis and examined preoperative and postoperative laboratory tests of coagulation and inflammation in neonates experiencing initial surgical palliation for variations of single ventricle physiology. Neonates (<30 days) requiring initial surgical palliation were studied. All subjects received aspirin from postoperative day 1 onward. Thromboses were diagnosed by serial transthoracic echocardiograms, vascular imaging, and interstage cardiac catheterizations according to predefined criteria. Twenty-two neonates, age 1 to 11 days (mean 4 +/- 2.5) were studied. Follow-up ranged from three hours to 18 months (median, 212 days). Eight infants died. Four of the 14 subjects who survived (28%), and one of the eight who died (12.5%), had evidence of thrombosis identified over a range of four hours to nine months postoperatively (median 14 days). When compared with reference values established in healthy children, preoperative subject hematocrit (Hct), platelet count, factors II, V, VII, VIII, and X, antithrombin, protein C, and soluble CD40 ligand measures were significantly lower, and the prothrombin time and partial thromboplastin time were significantly higher. Postoperative C reactive protein (CRP) was significantly higher, and Hct and platelet count significantly lower, than preoperative values. Thrombotic events were significantly related to high preoperative CRP (p = 0.02). Thrombotic complications occur frequently in neonates undergoing initial palliative surgery, suggesting that aspirin therapy alone may constitute inadequate protection. Elevated preoperative CRP appears to be associated with increased thrombotic risk.

Influence of urbanisation on asymptomatic malaria in school children in Molyko, South Western Cameroon

To determine the impact of urbanisation on the prevalence of asymptomatic malaria in Molyko, a rapidly urbanising area of South West Cameroon. A cross-sectional study. Molyko, South West Province Cameroon. One hundred and sixty six and two hundred and forty four randomly selected children in Molyko in the rainy seasons of 2000 and 2004 respectively. Prevalence and geometric mean parasite density of asymptomatic malaria, measurement of axillary temperatures and haematocrit (PCV) values in 2000 and 2004. There was a significant association between axillary temperature and malaria parasitaemia in both years (p<0.05). Overall, the prevalence of asymptomatic malaria and parasite density values in all age groups in 2004 were lower than in 2000 while the reverse was the case with PCV values. Urbanisation in Molyko has likely reduced the level of malaria endemicity in the area. It is advisable to repeat this study over a period of time in order to assess the long-term effects of urbanisation in the study area.

Avaliação laboratorial da deficiência de ferro em doadoras de sangue

O objetivo deste estudo foi avaliar a freqüência da deficiência de ferro em doadoras de sangue do Hemocentro da Santa Casa de São Paulo segundo o tipo de doador, o número total de doações anteriores e a freqüência de doações realizadas nos últimos 12 meses. No período de 05 a 20 de outubro de 2004 foram estudadas 100 doadoras de sangue utilizando-se a determinação da ferritina sérica e dos índices eritrocitários. A freqüência de doadoras de sangue que apresentavam deficiência de ferro foi de 16,0 %. Para as doadoras de primeira vez, 10,5% delas já apresentavam deficiência de ferro à primeira doação de sangue e, para aquelas que não eram de primeira vez, essa freqüência foi de 17,7% (p<0,05). Observamos que quanto maior o número total de doações de sangue, maior a freqüência de doadores com deficiência de ferro. A freqüência encontrada foi estatisticamente significante somente para as doadoras com mais de quatro doações (p<0,05). Constatamos que quanto maior o número de doações realizadas nos últimos 12 meses, maior a freqüência de doadoras com deficiência de ferro. A freqüência observada foi estatisticamente significante para as doadoras com duas ou mais doações nos últimos 12 meses (p<0,05). Concluímos que a doação de sangue constitui-se numa causa importante de deficiência de ferro, particularmente nas doadoras de repetição. A elevada freqüência de doadoras de sangue com deficiência de ferro observada neste estudo sugere a necessidade de uma triagem laboratorial mais acurada, uma vez que a determinação isolada da hemoglobina ou do hematócrito não é suficiente para detectar e excluir as doadoras com deficiência de ferro sem anemia.

Left Ventricular Volume Measurement by the Conductance Catheter and Variations in the Hematocrit in Small Animals

Cardiac performance is quantitatively and continuously assessed from pressure-volume signals by using the conductance catheter technique even in small animals. Conductivity of blood, however, is dependent on hematocrit (Hct). Interdependence between hematocrit and volume measurement by the conductance catheter has been evaluated. In 12 male Wistar rats weighing 400-475 g, anesthetized and artificially ventilated, Hct was gradually lowered by isovolumic hemodilution ranging from 50% to 7%. Heparinized blood samples were drawn at decreasing Hct levels for centrifugation, for automated Hct measurement by a blood gas analyzer, and for conductance catheter volume measurements (CCV) in calibrated cuvettes. Substitution of about 2 ml colloid solution lowered the Hct initially from 47 +/- 2% to 36 +/- 3%; at the same time, CCV output rose by 36 +/- 14% for definite blood volume. There is a strong inverse linear relationship (absolute value of r > 0.96; P < 0.0001) between relative volume units (RVU) displayed by the volume acquisition device and the hematocrit for any calibrated blood cuvette. Slopes of the regression lines increase proportionally to the calibration volumes (28.3 microl: -0.25; 63.6 microl: -0.57; 113.1 microl: -0.92). These data document the direct interdependence between Hct and CCV. Consequently, careful Hct correction of the RVU recordings is necessary especially in small animals where even small amounts of substituted solutions result in a marked decrease in Hct and, thus, in pronounced blood volume misreadings.

Time course of c-fos, vasopressin and oxytocin mRNA expression in the hypothalamus following long-term dehydration.

1. This study presents a time course analysis of the messenger RNA (mRNA) levels of c-fos, vasopressin (VP), and oxytocin (OT) in the paraventricular (PVN) and supraoptic nucleus (SON), following acute and chronic dehydration by water deprivation. 2. Male Wistar rats were separated into five groups: nondehydrated (control group) and dehydrated for 6, 24, 48 and 72 h. Following water deprivation, animals were decapitated, their blood was collected for hematocrit, osmolality, and plasma sodium measurements, and brains were removed for dissection of both PVN and SON. 3. As expected, the hematocrit, osmolality, plasma sodium, and weight loss were increased after water deprivation. In SON, a significant increase in both VP and OT mRNA expression was observed 6 h after dehydration reaching a peak at 24 h and returning to basal levels of expression at 72 h. In the PVN, an increase in both VP and OTmRNA expression occurred 24 h after dehydration. At 72 h the VP and OT mRNA expression levels had decreased but they were still at higher levels than those detected in control animals. 4. These results suggest that SON is the first nucleus to respond to the dehydration stimulus. Additionally, we also observed an increase in c-fos mRNA expression in both PVN and SON 6 h after water deprivation, which progressively decreased 24, 48, and 72 h after the onset of water deprivation. Therefore, it is possible that c-fos may be involved in the modulation of VP and OT genes, regulating the mRNA expression levels on a temporally distinct basis within the PVN and SON.

An Imaging Spectroscopy Approach for Measurement of Oxygen Saturation and Hematocrit During Intravital Microscopy

Oxygen supply and partial pressure are key determinants of tissue metabolic status and are also regulators of vascular function including production of reactive oxygen species, vascular remodeling, and angiogenesis. The objective of this study was to develop an approach for the determination of oxygen saturation and hematocrit for individual microvessels in trans- and epi-illumination intravital microscopy. A spectral approach was used, taking advantage of the availability of commercial imaging systems that allow digital recording of intravital images at a number of predetermined wavelengths within a relatively short time. The dependence of validity and precision of saturation measurements on critical experimental variables (reference spectra, number and selection of wavelengths, exposure time, analysis area, analysis model) was evaluated. In addition, a software approach for two-dimensional analysis of images was developed. Exposure times per wavelength of about 200 ms and use of up to 50 wavelengths evenly spaced from 500 to 598 nm allow automatic discrimination of microvessels from tissue background (segmentation) with reliable determination of oxygen saturation (in trans- and epi-illumination) and hematocrit (in transillumination). The present imaging spectroscopy approach allows detailed assessment of oxygen transport and other functional parameters at the microcirculatory level.

Role of Blood- and Tissue-Associated Inducible Nitric-Oxide Synthase in Colonic Inflammation

There is evidence that inducible nitric-oxide synthase (iNOS)-derived NO contributes to the pathophysiology of intestinal inflammation. The aims of this study were to assess the role of iNOS in the development of dextran sodium sulfate (DSS)-induced colonic inflammation and to define the contribution of tissue-specific iNOS expression to this inflammatory response. Study groups included: 1) wild-type (WT) mice; 2) WT=>WT bone marrow chimeras with normal iNOS function; 3) WT=>iNOS-/- chimeras (with functional blood cell iNOS, but iNOS-deficient tissue); 4) iNOS-/-=>WT chimeras (with iNOS-deficient blood cells, but normal tissue iNOS activity); and 5) iNOS-deficient mice. In WT mice and WT=>WT chimeras, DSS-induced colonic inflammation was characterized by bloody diarrhea and a high disease activity index. However, WT=>iNOS-/- and iNOS-/-=>WT chimeras and iNOS-/- mice exhibited an attenuated disease activity index, with parallel changes in histopathology. Colonic myeloperoxidase (MPO) was comparably elevated in DSS-treated WT mice (30.1+/-1.7) and WT=>WT chimeras (29.0+/-1), whereas MPO was significantly reduced in iNOS-/- mice and iNOS-/-=>WT chimeras (9.5+/-1.7 and 15.6+/-2.2, respectively). WT=>iNOS-/- chimeras exhibited the lowest MPO activity (3.7+/-0.6). Our findings implicate both blood cell- and tissue-derived iNOS in DSS-induced colonic inflammation, with tissue-associated iNOS making a larger contribution to the recruitment of inflammatory cells.

51Cr-EDTA measurements of the glomerular filtration rate in patients with sickle cell anaemia and minor renal damage

Creatinine clearance has been reported to be inaccurate for the estimation of glomerular filtration rate (GFR) in patients with sickle cell anaemia (SCA). Inulin clearance, the reference method for GFR estimation, is impractical for routine use in these patients, and 51Cr-EDTA measurements of the GFR have been rarely reported in this disease. In order to obtain reference 51Cr-EDTA values in this disease, we studied 70 patients (40 females; 13-59 years of age, mean: 31.6 years) with homozygous SCA, normal serum creatinine and urinary albumin excretion < or =200 microg x min(-1). All patients were submitted to single-injection 51Cr-EDTA GFR, urinary albumin and haematocrit measurements. 51Cr-EDTA clearances were calculated in different age groups (<20, 20-29, 30-39, 40-49 and >50 years). The mean GFR (+/-standard deviation) obtained for the 70 patients was 111.5+/-23.1 ml x min(-1). Analysis of variance for evaluation of the possible interaction effect between 51Cr-EDTA clearance and sex, age, urinary albumin and haematocrit demonstrated patient age as the only factor influencing 51Cr-EDTA clearance (P < 0.001). The Spearman correlation coefficient showed a significant relationship between 51Cr-EDTA clearance and patient age (r = -0.44, P = 0.0001), but not between 51Cr-EDTA and urinary albumin (r = -0.17, P = 0.1546) or haematocrit (r = 0.079, P = 0.5121). The group aged 20-29 years presented the highest 51Cr-EDTA clearance mean value (126.7+/-20.4 ml x min(-1)), with a progressive reduction in the older groups. Young adults with homozygous SCA, normal serum creatinine and micro-albuminuria or normo-albuminuria present supranormal 51Cr-EDTA GFR values. These values rapidly decrease after 30 years of age. We did not find association between urinary albumin and GFR in these patients.

A Non-Invasive Evaluation of Hemoglobin with a New Optical Sensor.

Background: The performance of the NBM-100, a new non-invasive Hematocrit (Hct) measurement device, was tested in primary and secondary medical care environments. The device utilizes a finger sensor with Occlusion Red/Near-Infrared Spectroscopy (O-RNIRS) technology to non-invasively measure hemoglobin and Hct levels (Figure). A non-invasive Hct measurement has many potential advantages including the prevention of pain and potential transmission of infectious diseases, and the reduced need for trained technicians.Methods: In order to investigate the use of the device in both primary and secondary medical environments, clinical trials were conducted in a blood donation center (USA), an oncology clinic (USA) and a hematology clinic (Israel). The studies were carried out on a group of 304 subjects (155 Female, 149 Male), ages 18–96 (average age 54.9).After signing a written consent, all study volunteers were tested non-invasively with the NBM-100 device, and invasively, using a venous sample evaluated on a Cell-Dyn (Abbott) blood analyzer. At the blood donation center the NBM-100 measurements were performed before donation, and the venous blood sample was taken after donation. To neutralize the decrease in Hct occurring during blood donation, as described in published clinical trials, a value of 2.2% was added to the reference venous values obtained from the blood donation center.Results: The operating staff at all centers found the NBM-100 easy to use and appreciated by subjects. The venous Hct measurements ranged from 15% to 51%. The mean NBM-100 Hct was 36%, the same as the mean venous result. The mean absolute error (MAE) was 2.66% and the relative absolute error (RAE) was 7.9%. The standard deviation of the difference between the venous reference and noninvasive Hct readings was found to be 3.34% and the correlation between the two devices was r=0.9. The bias between the two methods was a negligible 0.40%.Conclusions: This study supports the use of the NBM-100 device as a useful, safe and accurate non-invasive method for measuring a wide range of Hct in both a hospital (e.g. surgery and blood transfusions) and ambulatory setting (e.g. blood banks). Good agreement was found between the non-invasive NBM-100 and the invasive Cell-Dyn Hct measurements. The non-invasive system was found to be environmentally - and user-friendly by the operating staff. These findings support the high clinical utility of a commercial application of the NBM-100 device.

Safety and Efficacy of Subcutaneous Epoetin Delta for the Management of Anemia in Patients with Chronic Kidney Disease - A One Year Study.

Epoetin delta (Dynepo®, Shire plc) is the only erythropoietin synthesized in a human cell line. Currently available erythropoietins are all synthesized in Chinese hamster ovary cell (CHO) lines with differences in glycosylation compared with human serum erythropoietin. We report on a trial to assess the safety and efficacy of subcutaneously (s.c.) administered epoetin delta for the treatment of anemia in patients with chronic kidney disease (CKD) over 1 year of therapy. This was a multicenter trial, including predialysis, hemodialysis and peritoneal dialysis patients in the US and Europe. Eligible patients had baseline hemoglobin levels of 9.6–12.4 g/dL and had been receiving an epoetin s.c. for at least 30 days before entering the study. All patients received epoetin delta 1, 2 or 3-times per week, with the initial dose of study medication identical to the last dose of epoetin received prior to study entry. Dose was then adjusted according to a predefined algorithm to maintain hemoglobin in the range of 10–12 g/dL. Treatments were planned to continue for 52 weeks. Efficacy assessments were based upon weekly evaluation of hematological parameters (hemoglobin, hematocrit, red blood cell [RBC] and reticulocyte count) with the primary objective to assess mean hemoglobin levels over Weeks 12, 16, 20 and 24 in the group of patients who had provided at least one hemoglobin measurement during this period. In total 478 patients were treated, with 86.0% (411/478) entered into the primary efficacy analysis, 76.6% (366/478) completing at least 24 weeks of study and 66.7% (319/478) completing the study. Requirement for a RBC transfusion was the next most common specified reason for withdrawal (27 patients; 5.6%). The group withdrawn for “other” reasons was the largest (38 patients; 7.9%); it included a cohort of 19 patients withdrawn when the study terminated in the UK. This was a precautionary measure taken after a sterility test failure for a batch of study drug, although subsequent investigations discovered no contamination. Average hemoglobin level over Weeks 12, 16, 20 and 24 was 11.31 g/dL and average hematocrit was 36.4%. Hemoglobin levels of > 10.0 g/dL were recorded in 83.9% of patients over this period and 92.3% of hematocrit measurements were over 30%. Mean dose over this period was 43.3 IU/kg (84.3 IU/kg/week) and there was a slight decrease in average dose from baseline (49.6 IU/kg). Control of anemia over 52 weeks was maintained with long term analyses showing maintenance of hemoglobin in the range of 10–12 g/dL and hematocrit above 30%. Adverse events were experienced at the expected levels considering the baseline characteristics of the patient population. Subcutaneously administered epoetin delta was effective for the management of anemia in patients with CKD. Hemoglobin was maintained in the target range of 10–12 g/dL regardless of dialysis requirement and once per week dosing was sufficient to maintain hemoglobin levels. Subcutaneous administration of epoetin delta was well tolerated for up to 1 year and no patient in this study developed neutralizing anti-erythropoietin antibodies.