Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0240066 (iron deficiency)
 7,156 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Anemia is one of the most serious complications in patients on dialysis. Erythropoietin improves the anemia. However, erythropoietin resistance is sometimes encountered from causes such as functional iron deficiency, secondary hyperparathyroidism, blood loss, or interaction with other drugs. To clarify the interaction between erythropoietin and the renin-angiotensin system, we studied the maintenance dose of recombinant human erythropoietin (rHuEPO) in patients on continuous ambulatory peritoneal dialysis (CAPD) with and without angiotensin converting enzyme inhibitor (ACEIs), angiotensin II type I receptor blockers (ARBs), and calcium channel blockers. We divided 36 hypertensive patients on CAPD into three groups--an ACEI group (n = 12), an ARB group (n = 12), and a Ca channel blocker group (n = 12)--and then we compared the doses of rHuEPO required to maintain the patients' hematocrit (Hct) above 30%. In the Ca channel blocker group, the weekly dose of erythropoietin had not changed significantly at the end of the study (74 +/- 7 U/kg at the end vs. 76 +/- 8 U/kg at the start). The (oral) ACEI group needed a significantly higher weekly dose of erythropoietin at the end of the study (89 -/+ 9 U/kg at the end vs. 74 -/+ 8 U/kg at the start, p < 0.01). The (oral) ARB group also needed a significantly higher weekly dose of erythropoietin at the end of the study (82 -/+ 10 U/kg at the end vs. 76 +/- 8 U/kg at the start, p < 0.05). Furthermore, the weekly dose of erythropoietin required in the ACEI group was significantly larger than that required in the ARB group. We conclude that treatment with ACEIs and ARBs induces erythropoietin resistance in patients on CAPD. The inhibitory effect of ARBs on erythropoiesis is less than that of ACEIs.
Adv Perit Dial 2004
PMID:Erythropoietin resistance in patients on continuous ambulatory peritoneal dialysis. 1538 8

The guideline committee of Japanese Society for Dialysis Therapy (JSDT), chaired by Professor F. Gejyo of Niigata University, now publishes an original Japanese guideline entitled 'Guidelines for Renal Anemia in Chronic Hemodialysis Patients'. It includes the re-evaluation of the usage of recombinant human erythropoietin (rHuEPO) with the medical and economical arguments regarding the prognosis and the quality of life of Japanese hemodialysis patients. This guideline consists of 7 sections. The first section comprises the general definition and the differential diagnosis of anemia. The hemoglobin (Hb) level of the Japanese population seemed to be low when compared with that of the European and American populations. The second section describes the target Hb level in hemodialysis patients. Multivariate analysis of the data that were collected from dialysis institutions throughout the country showed that an Hb level of 10-11 g/dL (Ht level 30-33%) at the first dialysis session in a week is the ideal range for chronic hemodialysis patients in terms of the 3-5 year survival rate. The supine position at blood sampling and the sampling timing at the first dialysis session in a week might affect the lower setting of target Hb hematocrit (Ht), compared to that of European and American guidelines. However, we particularly recommended that an Hb level of 11-12 g/dL (Ht level from 33 to 36%) at the first dialysis session in a week is desirable in relatively young patients. In the third section, the markers of iron deficiency are discussed. The Transferin saturation test (TSAT) and serum ferritin were emphasized as the standard markers. The routes of administration of rHuEPO and its dosages are written in the fourth section. The subcutaneous route was associated with the occurrence of secondary red cell aplasia due to anti-rHuEPO antibodies; however, secondary red cell aplasia was seldom observed in the venous injection. From this fact we recommend venous injection for chronic hemodialysis patients. We advocate an initial dosage of 1500 U three times per week. The fifth section deals with the factors refractory to treatment with rHuEPO. If the patient shows an inadequate response to the usage of 9000 U per week, this condition defines the inadequate response to rHuEPO in Japan. Blood transfusion must be avoided where possible. The reasons for this and the adverse effects are interpreted in section six. In the final section, the adverse effects of rHuEPO are listed. Among them, hypertension, thrombotic events and secondary red cell aplasia were emphasized as the major complications.
Ther Apher Dial 2004 Dec
PMID:2004 Japanese Society for Dialysis Therapy guidelines for renal anemia in chronic hemodialysis patients. 1566 44

The medical care of renal anaemia has received much attention over the past decade, as nephrologists have recognized the increased therapeutic value of erythropoiesis-stimulating agents. The European Best Practice Guidelines and the US National Kidney Foundation's Kidney Disease Outcome Quality Initiative Guidelines have provided evidence-based advice on the optimal treatment of renal anaemia, and have recommended a target haemoglobin (Hb) level of 11 g/dl or 11-12 g/dl. Achieving this target Hb level has been shown to improve quality of life and reduce the rate of hospitalization; there is also good evidence to suggest that achieving adequate Hb levels reduces morbidity and mortality in patients with end-stage renal disease. In recent years, a number of factors have been identified that may counteract the positive action of epoetin therapy. These treatment-influencing factors include inadequate haemodialysis, absolute and functional iron deficiency, anticoagulant use, inflammation and infection. Each factor on its own may result in a substantial decrease in Hb levels, or an increase in epoetin requirements of up to 100%. Therefore, optimal and cost-effective treatment can only be achieved by adequately managing all of the factors that potentially can influence anaemia in patients with chronic kidney disease. Large-scale, cross-sectional surveys, such as the European Survey on Anaemia Management and the Dialysis Outcomes and Practice Patterns Study, have shown that there is still room for improving the efficacy and efficiency of anaemia therapy. The Optimal Treatment of Renal Anaemia (OPTA) initiative aims to help both physicians and nurses improve renal anaemia management by "translating" the standards set in published guidelines into practical clinical advice.
Nephrol Dial Transplant 2005 May
PMID:Optimal treatment of renal anaemia (OPTA): improving the efficacy and efficiency of renal anaemia therapy in haemodialysis patients receiving intravenous epoetin. 1582 27

The European Survey of Anaemia Management 2003 (ESAM 2003) was a 1 day randomized survey conducted to assess anaemia management in dialysis patients 4 years after the introduction of the European Best Practice Guidelines. The survey included 8100 patients from 11 European countries and Israel. Overall, haemoglobin (Hb) levels > or =11.0 g/dl, as recommended by the guidelines, were achieved in 66% of patients. Only 48% of patients had adequate iron status, with transferrin saturation values missing for 27% and functional or absolute iron deficiency reported for 17 and 9%, respectively. In order to identify factors affecting epoetin dose and Hb levels, the countries were divided into two groups based on the percentage of patients with Hb levels > or =11.0 g/dl (>70% in group 1 and 60-70% in group 2). The most probable causes for better management in group 1 were administration of higher epoetin doses and better monitoring and management of iron status. In patients with Hb <11.0 g/dl, mean epoetin-alpha/beta doses were significantly lower for subcutaneous than intravenous (i.v.) administration, whereas mean doses were similar for both routes in patients with Hb > or =11.0 g/dl. When standardized for Hb levels, the dose ratio of i.v. epoetin-alpha/beta to i.v. darbepoetin alfa was 176:1 (95% confidence interval, 166:1-189:1). Limited comparisons between the eight countries that participated in ESAM 2003 and the original ESAM revealed that many patients still have haemoglobin levels below the current recommendations despite significant improvements in management of renal anaemia over the last 5 years.
Nephrol Dial Transplant 2005 May
PMID:Results of the European Survey on Anaemia Management 2003 (ESAM 2003): current status of anaemia management in dialysis patients, factors affecting epoetin dosage and changes in anaemia management over the last 5 years. 1582 28

Current guidelines give evidence-based advice on how best to manage anaemia in patients with renal disease, but these guidelines do not consider individual patient needs, so tailoring anaemia management to each patient still remains a challenge for the treating physician. Two case studies are described that illustrate some of the key factors that need to be considered. The first case emphasizes that haemoglobin (Hb) targets recommended in current guidelines may not suit all patients. The patient had been stably maintained on subcutaneous epoetin therapy with an average Hb concentration of >13.0 g/dl because he developed angina symptoms when his Hb level fell to 12.2 g/dl. Iron deficiency was identified as the likely cause of falling Hb in this patient. After the patient's iron supplementation was increased, his Hb level was normalized back to >13.0 g/dl without increasing the epoetin dose, and the angina symptoms were resolved. The second case involved a pre-dialysis patient with diabetes, who required a higher dose of epoetin after beginning concomitant antihypertensive treatment with an angiotensin-converting enzyme inhibitor. Previously, the treatment of renal anaemia in pre-dialysis patients has not been the focus of attention. Two ongoing randomized controlled trials have been designed to study early initiation of epoetin treatment in pre-dialysis patients and will provide much needed information in this area.
Nephrol Dial Transplant 2005 Jun
PMID:Individualizing anaemia treatment: a discussion of case histories. 1595 26

The anemia of chronic kidney disease is associated with cardiovascular disease, decreased quality of life, and mortality. The introduction of recombinant human erythropoietin (rHuEPO) has transformed the management of this condition. However, a significant proportion of patients fail to respond to even high doses of rHuEPO. Several factors have been implicated in the hyporesponsiveness to rHuEPO. Iron deficiency, whether absolute or functional, is considered the most important, and maintenance of adequate iron stores reduces rHuEPO requirements among patients on hemodialysis. However, traditional indices of iron that are currently utilized may not reflect iron stores accurately, and there is also increasing concern regarding the potential long-term toxicity of parenteral iron therapy. Infection and inflammation also influence the response to rHuEPO, both by disruption of iron metabolism and by eliciting the release of cytokines that inhibit erythropoiesis. Oxidative stress may contribute to rHuEPO hyporesponsiveness directly by promoting lipid peroxidation in cell membranes, leading to increased erythrocyte fragility and reduced life span and also through its strong association with inflammation. Severe hyperparathyroidism can lead to a reduced number of erythroid progenitor cells. Inadequate dialysis dose, aluminum overload, nutritional factors such as deficiencies of carnitine, vitamin B12, folic acid, and vitamin C can also reduce the efficacy of rHuEPO therapy. Hyporesponsiveness to rHuEPO presents a challenge to both diagnosis and management in an era where optimizing response to rHuEPO is critical both in limiting the burgeoning costs of anemia management and improving clinical outcomes in the dialysis population.
Semin Dial
PMID:Managing erythropoietin hyporesponsiveness. 1655 Dec 93

Sleep complaints are very common in patients with end-stage renal disease (ESRD) and contribute to their impaired quality of life. Both obstructive and central sleep apnea syndromes are reported more often in patients on dialysis than in the general population. Impaired daytime functioning, sleepiness, and fatigue, as well as cognitive problems, are well known in patients with sleep apnea. Increasing evidence supports the pathophysiological role of sleep apnea in cardiovascular disorders, which are the leading cause of death in ESRD patients. Uremic factors may be involved in the pathogenesis of sleep apnea in this patient population and optimal dialysis may reduce disease severity. Furthermore, treatment with continuous positive airway pressure may improve quality of life and may help to manage hypertension in these patients. Secondary restless legs syndrome is highly prevalent in patients on maintenance dialysis. The pathophysiology of the disorder may also involve uremia-related factors, iron deficiency, and anemia, but genetic and lifestyle factors might also play a role. The treatment of restless legs syndrome involves various pharmacologic approaches and might be challenging in severe cases. In this article we review the diagnosis and treatment of sleep apnea and restless legs syndrome, with a focus on dialysis patients. We also briefly review current data regarding sleep problems after transplantation, since these studies may indirectly shed light on the possible pathophysiological role of uremia or dialysis in the etiology of sleep disorders. Considering the importance of sleep disorders, more awareness among professionals involved in the care of patients on dialysis is necessary. Appropriate management of sleep disorders could improve the quality of life and possibly even impact upon survival of renal patients.
Semin Dial
PMID:Diagnosis and management of sleep apnea syndrome and restless legs syndrome in dialysis patients. 1668 72

Resistance to erythropoietin therapy is a common complication of the modern management of anemia in chronic kidney disease. Iron deficiency, deficiency of other nutrients, toxins, infections, and inadequate dialysis account for the vast majority of episodes of such resistance.
Semin Dial
PMID:Erythropoietin resistance in the treatment of the anemia of chronic renal failure. 1689 3

We examined whether the use of non-steroidal anti-inflammatory drugs (NSAIDs) can affect the anemia and iron status of hemodialysis patients. We recruited patients from six dialysis centers who had undergone maintenance hemodialysis for at least four months. We examined the use of NSAIDs during the past three months based on their medical records and assigned the patients to three groups (group A, non-NSAID group; group B, aspirin group; and group C, non-aspirin NSAID group). Of the 446 patients, 95 (21.3%) were treated with aspirin and 103 (23.1%) were treated with non-aspirin NSAIDs. The serum iron level and transferrin saturation (TSAT) were significantly lower in group C patients than those in group A. However, the ratio of the patients who were administrated iron preparations during the past three months was significantly higher than that in the other two groups. The incidences of positive fecal occult blood tests did not differ substantially between the three groups. The ratios of the patients who were administrated recombinant human erythropoietin were the same between three groups. Using a multiple regression analysis, the administration of non-aspirin NSAIDs was identified as an independent factor for the decreased serum iron and the decreased TSAT levels. A multiple logistic regression analysis revealed that the patients using non-aspirin NSAIDs had an increased the requirement for iron preparation therapy (OR 2.03, 95% CI, 1.28-3.22). The use of non-aspirin NSAIDs may therefore increase the risk of the iron deficiency in patients undergoing hemodialysis.
Ther Apher Dial 2007 Jun
PMID:Iron status and the use of non-steroidal anti-inflammatory drugs in hemodialysis patients. 1749 4

Under normal conditions, reticulocytes are the youngest erythrocytes released from the bone marrow into circulating blood. They mature for 1-3 days within the bone marrow and circulate for 1-2 days before becoming mature erythrocytes. Measurement of cellular hemoglobin concentration has long been reported by automated hematology analyzers as one of the red blood cell indices. The reticulocyte hemoglobin content (CHr or Ret-He) provides an indirect measure of the functional iron available for new red blood cell production over the previous 3-4 days. Measurement of reticulocyte hemoglobin content in peripheral blood samples is useful for diagnosis of iron deficiency in adults (Mast et al., Blood 2002;99:1489-1491) and children (Brugnara et al., JAMA 1999;281:2225-2230; Ullrich et al., JAMA 2005;294:924-930; Bakr and Sarette, Eur J Pediatr 2006;165:442-445). It provides an early measure of the response to iron therapy increasing within 2-4 days of the initiation of intravenous iron therapy (Brugnara et al., Blood 1994;83:3100-3101). Sequential measurements of reticulocyte hemoglobin content in patients with iron deficiency anemia provide a rapid means for assessing the erythropoietic response to iron replacement therapy (Brugnara et al., Blood 1994;83:3100-3101). It is also an early indicator or iron-restricted erythropoiesis in patients receiving erythropoietin therapy (Fishbane et al., Kidney Int 1997;52:217-222; Fishbane et al., Kidney Int 2001;60:2406-2411; Mittman et al., Am J Kidney Dis 1997;30:912-922; Tsuchiya et al., Clin Nephrol 2003;59:115-123; Chuang et al., Nephrol Dial Transplant 2003;18:370-377). Thus, reticulocyte hemoglobin content is a recent addition to an expanding list of biomarkers that can be used to differentiate iron deficiency from other causes of anemia.
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PMID:Reticulocyte hemoglobin content. 1802 35


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