Discriminating between iron deficiency anemia and anemia of chronic disease using traditional indices of iron status vs transferrin receptor concentration

Inflammation indices in association with periodontitis and cancer

Inflammation is a complex physiological process that plays a pivotal role in many if not all pathological conditions, including infectious as well as inflammatory diseases, like periodontitis and autoimmune disorders. Inflammatory response to periodontal biofilms and tissue destruction in periodontitis is associated with the release of inflammatory mediators. Chronic inflammation can promote the development of cancer. Persistence of inflammatory mediators plays a crucial role in this process. Quantification and monitoring of the severity of inflammation in relation to cancer is essential. Periodontitis is mainly quantified based on the severity and extent of attachment loss and/or pocket probing depth, in addition with bleeding on probing. In recent years, studies started to investigate inflammation indices in association with periodontal diseases. To date, only few reviews have been published focusing on the relationship between blood cell count, inflammation indices, and periodontitis. This review presents a comprehensive overview of different systemic inflammation indices, their methods of measurement, and the clinical applications in relation to periodontitis and cancer. This review outlines the physiological basis of inflammation and the underlying cellular and molecular mechanisms of the parameters described. Key inflammation indices are commonly utilized in periodontology such as the neutrophil to lymphocyte ratio. Inflammation indices like the platelet to lymphocyte ratio, platelet distribution width, plateletcrit, red blood cell distribution width, lymphocyte to monocyte ratio, delta neutrophil index, and the systemic immune inflammation index are also used in hospital settings and will be discussed. The clinical roles and limitations, relationship to systemic diseases as well as their association to periodontitis and treatment response are described.

The Relationship between Complement Components C1R and C5 Gene Polymorphism and the Values of Blood Indices in Suckling Piglets

The main mechanism of innate immunity is the complement system. Its components include the protein products of the C1R and C5 genes, which are involved in the classical activation pathway as well as the inflammatory and cytolytic immune responses, respectively. The aim of this study was to determine the relationship between PCR-restriction fragment length polymorphism in C1R (726T > C) and C5 (1044A > C) genes, and the values of hematological and biochemical blood indices in suckling crossbred (Polish Large White × Polish Landrace × Duroc × Pietrain) piglets (n = 473), considering their age (younger, 21 ± 3 days, n = 274; older, 35 ± 3 days, n = 199) and health status. The frequencies of the C5 genotypes deviated from the Hardy-Weinberg expectations. Younger piglets, healthy piglets, piglets that deviated from physiological norms and older piglets with the C1R TT genotype all had lower white and red blood cell indices. In piglets with the C5 CC genotype, younger piglets, piglets that deviated from physiological norms and older piglets, a greater number and/or percentage of monocytes were recorded in the blood. Older piglets also showed an increase in the number of leukocytes and granulocytes, along with a tendency for a decrease in the percentage of lymphocytes in their blood. We concluded that a polymorphism in the C1R gene may exhibit a functional association or genetic linkage with other genes involved in the process of erythropoiesis. Furthermore the relationship between the C5 gene polymorphism and the number and/or percentage of monocytes in the blood may modify the body's defense abilities. Piglets with the CC genotype, having an increased number/proportion of these cells in their blood, probably display a weakened immune response to pathogens or a chronic stimulation of the immune system.

Iron metabolism disorders of patients with chronic paracoccidioidomycosis

Paracoccidioidomycosis (PCM) is caused by Paracoccidioides spp.; during infection, some host mechanisms limit the availability of iron, thereby reducing its reproduction. However, Paracoccidioides spp. can evade the immune defense and, even under limited iron conditions, use this mineral for growth and dissemination. This study evaluated the iron metabolism of 39 patients who were diagnosed with chronic PCM from 2013 to 2021. The forms of iron before treatment and at the time of clinical cure were evaluated based on the following: serum ferritin levels (storage iron); total iron-binding capacity (TIBC) and transferrin saturation (TSAT) level (transport iron); red blood cell (RBC), hemoglobin (Hb), hematocrit (HCT), and soluble transferrin receptor (sTfR) levels; and sTfR/log ferritin ratio (functional iron). The mean age of the patients was 54.5 years (±6.7 years). Most patients were men (97.4%), rural workers (92.1%), and smokers (84.6%); furthermore, most had moderate disease severity (66.7%). After achieving clinical cure, we observed that serum ferritin levels decreased, and parameters of functional iron increased. The extent of alteration in these parameters were more pronounced in severe cases than in to mild or moderate cases. Furthermore, moderate correlations were observed between C-reactive protein and the Hb (r = -0.500; p = 0.002), RBC (r = -0.461; p = 0.005), HCT (r = -0.514; p = 0.001), and iron levels (r = -0.491; p = 0.002). However, it is possible to infer that PCM interferes with functional and storage iron because improvements in these parameters after treatment as well as associations with disease severity were observed. PCM can lead to anemia of inflammation, which can be differentiated from iron deficiency anemia by a careful investigation of the iron form parameters.

Effect of hemoglobin extracted from Tegillarca granosa on iron deficiency anemia in mice

Iron deficiency anemia (IDA) is the most common nutritional deficiency in the world. This study was aimed to evaluate the therapeutic effects of hemoglobin from Tegillarca granosa (T. granosa) on IDA in mice. Mice were randomly divided into five groups: a normal control group, an anemia model group, a positive (FeSO₄) control group, a low-dose and high-dose hemoglobin groups. After 4-week iron supplements administration, it was observed that hemoglobin at 2.0 mg iron/kg body weight had better restorative effective on IDA mice than that of FeSO₄ with regard to routine blood parameters and serum biochemical indicators. Meanwhile, the IDA-caused alterations of organ coefficients and liver morphology were ameliorated in mice after hemoglobin supplementation in a dose-dependent manner. Further correlation analysis of indicators showed that serum ferritin (iron storage protein) and soluble transferrin receptor (cellular iron uptake membrane glycoprotein) were susceptible to iron deficiency, indicating possibledisorder of iron metabolism caused by IDA. And levels of serum ferritin and soluble transferrin receptor were restored after administration of hemoglobin. These findings confirmed the safety and effectiveness of T. granosa derived hemoglobin in alleviating IDA in mice, suggesting its great potential as an alternative for iron supplementation.

Usefulness of Soluble Transferrin Receptor in the Diagnosis of Iron Deficiency Anemia in Rheumatoid Arthritis Patients in Clinical Practice

Aim. We analyzed the added value of sTfR measurement in routine clinical practice to standard parameters (SP) of iron deficiency in the detection of iron deficiency anemia (IDA) in patients with rheumatoid arthritis (RA). Methods. Blood samples from 116 patients with RA were analyzed in a prospective study. Based on biochemical parameters, patients were classified as having IDA, anemia of chronic disease (ACD), IDA with concomitant ACD (ACD/IDA), or “other anemia.” Sensitivity, specificity, positive (PPV), and negative predictive values (NPV) of sTfR and SP of iron status alone and in combination were calculated for the diagnosis of IDA in general, i.e., IDA or ACD/IDA. Results. In the whole sample, with regard to the diagnosis of iron deficiency (IDA or ACD/IDA), sTfR had a higher sensitivity compared both to the combined use of SP and to the combination of SP with sTfR (80.9% versus 66.7/54.8%). Specificity, PPV and NPV did not differ substantially. When patients were stratified in groups with high (CRP levels above the median, i.e., 24.1 mg/l) and low (CRP levels less or equal to the median) inflammation, the diagnostic superiority of sTfR was restricted to patients with high inflammation. In this group, the diagnostic performance of sTfR was superior both to the combined use of SP and the combination of SP with sTfR with higher sensitivity (100% versus 52.4%) and NPV (100% versus 77.7/76.7%) and comparable specificity and PPV. Conclusion. For the detection of iron depletion (IDA or ACD/IDA) in anemic RA patients, sTfR is superior to SP of iron deficiency only in highly inflammatory states.

The prognostic impact of preoperative mean corpuscular volume in colorectal cancer

OBJECTIVE

The relationship between preoperative mean corpuscular volume and postoperative prognosis has been reported in some cancers recently, but no certain consensus has been reached, especially for colorectal cancer. We evaluated the usefulness of mean corpuscular volume as a prognostic factor in colorectal cancer patients.

METHODS

This study included 1003 patients with colorectal cancer who underwent curative surgery in a single institution. The relationship between mean corpuscular volume values and postoperative recurrence was evaluated by fractional polynomial model. Based on the result, patients were divided into groups according to mean corpuscular volume values. Clinicopathological factors and long-term outcomes were compared between the groups.

RESULTS

The risk of postoperative recurrence according to mean corpuscular volume value showed a J-shaped curve, suggesting that both low and high mean corpuscular volume have high risk. Low mean corpuscular volume (≤84 fl) group was oncologically advanced in terms of pathological tumor stage, histological grade and lymphatic invasion with higher inflammation markers. High mean corpuscular volume (>95 fl) group had higher frequency of drinking habit with higher values of aspartate aminotransferase, alanine aminotransferase and γ-glutamyl transpeptidase. Abnormal mean corpuscular volume group including these two groups showed significantly worse disease-free survival than the other (P < 0.001). Multivariate analysis suggested that abnormal mean corpuscular volume was an independent risk factor for postoperative recurrence (hazard ratio, 1.344; 95% confidence interval, 1.005-1.796; P = 0.046). Furthermore, its prognostic impact was more significant in pStage III than in other stages.

CONCLUSION

Preoperative low and high mean corpuscular volume is a poor prognostic factor in colorectal cancer patients. It could be a predictive marker to estimate worse survival outcome after surgery.

Plant-Based Dietary Practices and Socioeconomic Factors That Influence Anemia in India

While rates of malnutrition have declined over the last decade in India due to successful government interventions, the prevalence of anemia remains high. Staple foods provide almost 70% of the daily iron intake. As staple foods are a rich source of phytate, this ingested iron is poorly absorbed. Currently, 59% of children below 3 years of age, 50% of expectant mothers and 53% of women aged 15-19 years are anemic. The most common intervention strategy has been through the use of iron supplements. While the compliance has been low and supplies irregular, such high rates of anemia cannot be explained by iron deficiency alone. This review attempts to fit dietary and cooking practices, field-level diagnostics, cultural beliefs and constraints in implementation of management strategies into a larger picture scenario to offer insights as to why anemia continues to plague India. Since the rural Indian diet is predominantly vegetarian, we also review dietary factors that influence non-heme iron absorption. As a reference point, we also contrast anemia-related trends in India to the U.S.A. Thus, this review is an effort to convey a holistic evaluation while providing approaches to address this public health crisis.

A clinical calculator for predicting intraoperative blood loss and transfusion risk in spine tumor patients

BACKGROUND CONTEXT

Surgery for vertebral column tumors is commonly associated with intraoperative blood loss (IOBL) exceeding 2 liters and the need for transfusion of allogeneic blood products. Transfusion of allogeneic blood, while necessary, is not benign, and has been associated with increased rates of wound complication, venous thromboembolism, delirium, and death.

PURPOSE

To develop a prediction tool capable of predicting IOBL and risk of requiring allogeneic transfusion in patients undergoing surgery for vertebral column tumors.

STUDY DESIGN/SETTING

Retrospective, single-center study.

PATIENT SAMPLE

Consecutive series of 274 patients undergoing 350 unique operations for primary or metastatic spinal column tumors over a 46-month period at a comprehensive cancer center OUTCOME MEASURES: IOBL (in mL), use of intraoperative blood products, and intraoperative blood products transfused.

METHODS

We identified IOBL and transfusions, along with demographic data, preoperative laboratory data, and surgical procedures performed. Independent predictors of IOBL and transfusion risk were identified using multivariable regression.

RESULTS

Mean age at surgery was 57.0±13.6 years, 53.1% were male, and 67.1% were treated for metastatic lesions. Independent predictors of IOBL included en bloc resection (p<.001), surgical invasiveness (β=25.43 per point; p<0.001), and preoperative albumin (β=-244.86 per g/dL; p=0.011). Predictors of transfusion risk included preoperative hematocrit (odds ratio [OR]=0.88 per %; 95% confidence interval [CI, 0.84, 0.93]; p<0.001), preoperative MCHgb (OR=0.88 per pg; 95% CI [0.78, 1.00]; p=0.048), preoperative red cell distribution width (OR=1.32 per %; 95% CI [1.13, 1.55]; p<0.001), en bloc resection (OR=3.17; 95%CI [1.33, 7.54]; p=0.009), and surgical invasiveness (OR=1.08 per point; [1.06; 1.11]; p<0.001). The transfusion model showed a good fit of the data with an optimism-corrected area under the curve of 0.819. A freely available, web-based calculator was developed for the transfusion risk model (https://jhuspine3.shinyapps.io/TRUST/).

CONCLUSIONS

Here we present the first clinical calculator for intraoperative blood loss and transfusion risk in patients being treated for primary or metastatic vertebral column tumors. Surgical invasiveness and preoperative microcytic anemia most strongly predict transfusion risk. The resultant calculators may prove clinically useful for surgeons counseling patients about their individual risk of requiring allogeneic transfusion.

Insulin Resistance and Chronic Hepatitis C: Relationship With Serum Iron and Hepcidin

Backgrounds and aim

Besides the clinical evidence supporting insulin resistance in chronic hepatitis C (CHC) patients, the exact mechanism elucidating insulin resistance is still under discussion. The present study aimed to observe any relationship between serum hepcidin, serum iron, and insulin resistance in CHC patients.

Methodology

A total of 54 individuals were recruited in this study, assorted into group A (CHC population with diabetes) and control group B (CHC population without diabetes). Both groups were tested for serum hepcidin, iron, ferritin, and serum glycemic indices (fasting blood glucose, serum insulin, and insulin resistance). Serum parameters were compared between diabetic and non-diabetic CHC patients by using the Mann-Whitney U test. Correlation analysis was done between serum hepcidin and serum iron, serum hepcidin, and insulin resistance, and serum iron and insulin resistance by applying the Spearman correlation test.

Results

Diabetic and non-diabetic CHC populations exhibited an iron profile of chronic illness, i.e., low serum iron and hepcidin along with normal ferritin levels. Also, the diabetic and non-diabetic CHC population exhibited normal serum insulin and insulin resistance. However, the fasting serum glucose of the diabetic CHC population was higher than normal. Correlation analysis indicated a negative significant correlation (rho=-0.404, p=0.036) between serum iron and insulin resistance among the diabetic CHC population.

Conclusion

Our study could not provide any mounting evidence in favor of insulin resistance in the chronic hepatitis C population via serum iron or hepcidin. Hepatitis C virus causing diabetes mellitus may have some etiology other than iron metabolism.

Predictors of iron-deficiency anemia in primary care older adults: a real-world European multi-country longitudinal study

BACKGROUND

Iron deficiency is a major cause of anemia in older people. Increasing the knowledge on the predictors of iron-deficiency anemia (IDA) may facilitate its timely diagnosis.

AIM

To investigate the predictors of IDA in older people in four European countries.

DESIGN AND SETTING

Retrospective longitudinal study. Primary care patients aged 65 or older (N = 24,051) in four European countries.

METHODS

IDA predictors were estimated using multivariate Cox regression based on information gathered from national primary care databases: Italy (years 2002-2013), Belgium, Germany and Spain (years 2007-2012). Adjusted hazard ratios (aHR) with 95% confidence intervals (CIs) were estimated.

RESULTS

In Spain and Belgium, men were at greater risk of IDA than women, while they had a lower risk in Italy. Weakness, irritability, alopecia and xerostomia were signs and symptoms significantly associated with IDA. Concurrent diseases, potential causes of anemia, positively associated with IDA were small bowel polyposis, stomach cancer, obesity, gastritis and peptic ulcer, esophagitis, Crohn's disease, celiac disease, lymphangiectasis, gastrectomy or gastric atrophy, gut resection or bypass, and cardiac prosthetic valve. Aspirin users had a 12-35% higher hazard of IDA than non-users. Similarly, corticosteroids and anti-acids were positively associated with IDA. A higher level of comorbidity was associated with an increased hazard of IDA in all countries.

CONCLUSIONS

Specific signs and symptoms, chronic conditions, a greater comorbidity burden, and specific pharmacological treatments registered in primary care databases represent relevant predictors and correlates of incident IDA in older people in Europe. General practitioners might employ this information to obtain early diagnosis of IDA in community-dwelling older adults.

Prevalence and Risk Factors for Iron Deficiency in Adults With Cystic Fibrosis

BACKGROUND

Iron deficiency is common in cystic fibrosis (CF), but previous prevalence studies often reported results confounded by acute exacerbations. This single-center retrospective study aimed to identify the prevalence of iron deficiency in a stable adult CF population, identify the risk factors associated with iron deficiency, and compare common laboratory indicators of iron status.

METHODS

Medical charts of 105 patients aged 18-67 were reviewed to determine the prevalence of anemia. Of these patients, a subgroup of 67 were included in analyses of iron deficiency, defined as serum ferritin < 12 ng/mL and/or percent transferrin saturation (TSAT) < 16%. Data on sex, age, body mass index, anemia status, vitamin deficiencies, presence of comorbidities, colonization with Pseudomonas aeruginosa, and use of acid blockers and CF transmembrane conductance regulator modulators were collected to evaluate relationship of iron deficiency with these clinical factors. κ agreements between serum iron, ferritin, transferrin, and TSAT were compared.

RESULTS

In this stable CF population, the prevalence of iron deficiency was 41.8% (n = 67), and the prevalence of anemia was 33.3% (n = 105). Iron deficiency was associated with presence of anemia (P < .001), vitamin A deficiency (P = .012), and moderate (P = .047) and severe lung disease (P = .045) compared with mild lung disease. Transferrin agreed poorly with other iron status indicators.

CONCLUSION

Iron deficiency is common in CF, although prevalence rates can vary widely depending on the laboratory parameters used. CF centers should consider routine screening for iron deficiency.

Gender differences in determinants of iron-deficiency anemia: a population-based study conducted in four European countries

Iron-deficiency anemia (IDA) was the main condition contributing to higher rates of years lived with disabilities in women in 2016. To date, few studies have investigated gender differences in determinants of IDA in Europe. The aim of the present study was to evaluate the determinants of IDA among females and males in four European countries. IDA determinants were estimated using multivariable Cox regression based on information gathered from national primary care databases, namely Italy (for years 2002-2013), Belgium, Germany, and Spain (for years 2007-2012). Adjusted hazard ratios (aHR) with 95% confidence intervals (CIs) were estimated. Age was significantly associated with IDA in females of childbearing age in all four countries, as well as pregnancy, for which the aHR ranged from 1.20 (95% CI 1.15-1.25) in Italy to 1.88 (95% CI 1.53-2.31) in Germany. In males, the aHR increased with age starting from the 65-69 age group. Menometrorrhagia was associated with IDA in Germany (aHR 2.71, 95% CI 1.96-3.73), Italy (aHR 1.80, 95% CI 1.60-2.03), and Spain (aHR 1.52, 95% CI 1.31-1.76). A greater risk for women with alopecia was also observed. Weakness and headache indicated a higher risk in both men and women. Patients with diseases characterized by blood loss or gastrointestinal malabsorption were also at significantly increased risk. Physicians should encourage women of childbearing age to adhere to dietary recommendations regarding iron intake and regularly prescribe screening of iron status. Upper and lower gastrointestinal investigations should be recommended for patients with a confirmed diagnosis of IDA.

[Anemia and dysregulation of iron metabolism in multiple sclerosis]

Anemia is one of the common diseases comorbid with multiple sclerosis (MS). This article reviews the prevalence and types of anemia in MS patients. It has been shown that anemia is often accompanied by a decrease in serum iron level. The authors present the data on iron metabolism in patients with MS and MRI findings concerning deposits of iron in the gray matter of the brain. The causal relationship between abnormalities in iron metabolism and MS remains unclear; this study allows to approach the understanding of the MS pathogenesis and to increase the efficacy of therapy for this disease.

Investigation and management of a raised serum ferritin

Serum ferritin level is one of the most commonly requested investigations in both primary and secondary care. Whilst low serum ferritin levels invariably indicate reduced iron stores, raised serum ferritin levels can be due to multiple different aetiologies, including iron overload, inflammation, liver or renal disease, malignancy, and the recently described metabolic syndrome. A key test in the further investigation of an unexpected raised serum ferritin is the serum transferrin saturation. This guideline reviews the investigation and management of a raised serum ferritin level. The investigation and management of genetic haemochromatosis is not dealt with however and is the subject of a separate guideline.

The Saudi Diabetic Kidney Disease study (Saudi-DKD): clinical characteristics and biochemical parameters

BACKGROUND

Saudi Arabia is facing an epidemic of type 2 diabetes that is complicated by a high rate of chronic complications such as kidney disease, which have a major impact on the healthcare system and economy. The Saudi diabetic kidney disease (SAUDI-DKD) study was launched to understand the implications of chronic diabetic kidney disease .

OBJECTIVES

Examine the hematological, biochemical and metabolic parameters of the selected cohorts to look for biomarkers of diabetic nephropathy.

DESIGN

Cross-sectional, hospital-based.

SETTING

Four general hospitals and two dialysis centers in Riyadh.

PATIENTS AND METHODS

We recruited adult type 2 diabetic patients aged between 35 and 70 years, with a duration of diabetes > 10 years, including subjects with microalbuminuria, macroalbuminuria and end stage renal disease (ESRD). They were compared with subjects with normal albumin excretion classified according to American Diabetes Association (ADA) criteria.

MAIN OUTCOME MEASURES

The effect of different stages of diabetic nephropathy on hematological and biochemical parameters.

RESULTS

Of 427 subjects with nephropathy, 184 (43%) had microalbuminuria, 83 (19%) had macroalbu.minuria and 160 (37%) had end stage renal disease (ESRD). The remaining 213 (50%) subjects did not have nephropathy. Patients with nephropathy were older with a mean age (SD) of 55.62 (6.00) years and had a longer duration of diabetes (mean [SD], 19.04 [6.33]) years), and had a lower monthly income and body mass index (BMI) than patients without nephropathy. Insulin resistance, elevated uric acid level, low red blood cells (RBCs) count and low hemoglobin level were associated with significantly increased risk of macroalbuminuria and ESRD. Elevated uric acid and LDH were associated with significantly increased risk of microalbuminuria and ESRD, while elevated red blood cell distribution width was significantly associated with an increased risk of ESRD.

CONCLUSION

Diabetic nephropathy is associated with insulin resistance, changes in liver enzymes and uric acid in addition to abnormalities in the red blood cell count and red blood cell shape that warrant frequent monitoring among patients with diabetic kidney disease.

LIMITATIONS

Cross-sectional study design and exclusion of patients with some risk factors.

Dietary Composition Influences Incidence of Helicobacter pylori-Induced Iron Deficiency Anemia and Gastric Ulceration

Epidemiologic studies have provided conflicting data regarding an association between Helicobacter pylori infection and iron deficiency anemia (IDA) in humans. Here, a Mongolian gerbil model was used to investigate a potential role of H. pylori infection, as well as a possible role of diet, in H. pylori-associated IDA. Mongolian gerbils (either H. pylori infected or uninfected) received a normal diet or one of three diets associated with increased H. pylori virulence: high-salt, low-iron, or a combination of a high-salt and low-iron diet. In an analysis of all infected animals compared to uninfected animals (independent of diet), H. pylori-infected gerbils had significantly lower hemoglobin values than their uninfected counterparts at 16 weeks postinfection (P < 0.0001). The mean corpuscular volume (MCV) and serum ferritin values were significantly lower in H. pylori-infected gerbils than in uninfected gerbils, consistent with IDA. Leukocytosis and thrombocytosis were also detected in infected gerbils, indicating the presence of a systemic inflammatory response. In comparison to uninfected gerbils, H. pylori-infected gerbils had a higher gastric pH, a higher incidence of gastric ulcers, and a higher incidence of fecal occult blood loss. Anemia was associated with the presence of gastric ulceration but not gastric cancer. Infected gerbils consuming diets with a high salt content developed gastric ulcers significantly more frequently than gerbils consuming a normal-salt diet, and the lowest hemoglobin levels were in infected gerbils consuming a high-salt/low-iron diet. These data indicate that H. pylori infection can cause IDA and that the composition of the diet influences the incidence and severity of H. pylori-induced IDA.

Generalized, severe, chronic periodontitis is associated with anemia of chronic disease: a pilot study in urban, Indian males

AIM

Anemia of chronic disease, a cytokine-mediated anemia, is a frequent complication of many chronic inflammatory conditions. The present case-control study was aimed to evaluate levels of systemic hematological markers indicative of anemia in patients with generalized, severe, chronic periodontitis.

METHODS

A convenience quota sample of 30 systemically-healthy, urban, male patients comprised two groups, based on full mouth periodontal examination: group A patients (n=15) were diagnosed with generalized, severe, chronic periodontitis, and group B patients comprised the control group (n=15), which included patients with a clinically-healthy periodontium. Laboratory blood investigations included hemoglobin (g%), total number of erythrocytes (red blood cells), hematocrit/packed cell volume, erythrocyte sedimentation rate, mean corpuscular volume of erythrocytes, and mean corpuscular hemoglobin concentration. An analysis of covariance using age as a covariate was done to compare the mean values of hematological parameters within groups.

RESULTS

The mean values of hemoglobin, red blood cells, packed cell volume, and mean corpuscular hemoglobin concentration were significantly lower, while the mean corpuscular volume of erythrocytes and erythrocyte sedimentation rate were significantly higher in group A patients compared to those in group B, indicating mild anemia.

CONCLUSIONS

Severe periodontal disease can be linked with anemic status.

The early detection of anaemia and aetiology prediction through the modelling of red cell distribution width (RDW) in cross-sectional community patient data

Red cell distribution width (RDW) is a marker of iron-deficient anaemia that can also assist differentiation of other anaemias. RDW also has been suggested as an effective marker for earlier anaemia detection. The RDW-anaemia relationship was investigated in cross-sectional community patient data, and the capacity of RDW to predict the diagnostic value of second tier anaemia markers assessed.

Routine and second tier assay data were provided by the laboratory Sullivan Nicolaides Pathology. The cohort was divided into male and female groups stratified by age, and correlation analyses assessed associations of RDW to haemoglobin and ferritin. Analysis of covariance (ANCOVA) was performed for both routine and second tier markers to investigate their significance for RDW prediction.

RDW had statistically significant negative correlation with haemoglobin for both sexes and age ranges (p<0.01). The RDW relationship with serum ferritin was non-linear, representing two populations. ANCOVA showed categorical ferritin as a significant RDW predictor for younger females, with vitamin B12 a significant RDW predictor for older men. Haemoglobin, mean corpuscular haemoglobin (MCH) and second tier iron markers (e.g., transferrin) were significant RDW predictors for both sexes and ages investigated. An individual longitudinal female case study showed RDW as very sensitive to haemoglobin decrease, with ferritin not as responsive.

RDW had a significant negative association with haemoglobin in cross-sectional community patient data. ANCOVA showed ferritin as a significant RDW predictor for younger females only. This study confirms the utility of RDW as a marker for early anaemia detection, and useful to accelerated diagnoses of anaemia aetiology.

Pre-operative anaemia

Pre-operative anaemia is a relatively common finding, affecting a third of patients undergoing elective surgery. Traditionally associated with chronic disease, management has historically focused on the use of blood transfusion as a solution for anaemia in the peri-operative period. Data from large series now suggest that anaemia is an independent risk associated with poor outcome in both cardiac and non-cardiac surgery. Furthermore, blood transfusion does not appear to ameliorate this risk, and in fact may increase the risk of postoperative complications and hospital length of stay. Consequently, there is a need to identify, diagnose and manage pre-operative anaemia to reduce surgical risk. Discoveries in the pathways of iron metabolism have found that chronic disease can cause a state of functional iron deficiency leading to anaemia. The key iron regulatory protein hepcidin, activated in response to inflammation, inhibits absorption of iron from the gastrointestinal tract and further reduces bioavailability of iron stores for red cell production. Consequently, although iron stores (predominantly ferritin) may be normal, the transport of iron either from the gastrointestinal tract or iron stores to the bone marrow is inhibited, leading to a state of 'functional' iron deficiency and subsequent anaemia. Since absorption from the gastrointestinal tract is blocked, increasing oral iron intake is ineffective, and studies are now looking at the role of intravenous iron to treat anaemia in the surgical setting. In this article, we review the incidence and impact of anaemia on the pre-operative patient. We explain how anaemia may be caused by functional iron deficiency, and how iron deficiency anaemia may be diagnosed and treated.

Adolescent life-event stress in boys is associated with elevated IL-6 and hepcidin but not hypoferremia

OBJECTIVE

The link between stress-related increases in inflammatory markers, hepcidin, and iron status are poorly understood, especially in developing countries like India. The aim of the study was to examine the relationship between adolescent life-event stress (ALES), inflammatory markers, and its association with hepcidin and biomarkers of iron status among adolescent boys.

METHODS

Data pertaining to a subsample of 145 participants from a cross-sectional, school-based study recruiting 370 adolescent boys aged 15-19 years, from 5 schools in Hyderabad, India, were analyzed. Stress was assessed using the ALES scale, psychological distress by the General Health Questionnaire-2 (GHQ-12), and approach and avoidance coping using the Coping Strategies Scale. Biomarkers of iron and concentrations of other micronutrients, hepcidin, IL-6 and C-reactive protein (CRP) in plasma were analyzed. Data were subjected to regression, path analyses, and analysis of covariance (ANCOVA).

RESULTS

ALES was a significant predictor of interleukin (IL)-6 (β = 0.196, p = 0.012), CRP (β = 0.217, p = 0.010), and log hepcidin (β = 0.228, p = 0.006). Hepcidin correlated significantly (p < 0.001) with IL-6 (r = 0.344) and CRP (r = 0.370) but not with the biomarkers of iron status. Path analysis showed that the model had an acceptable fit, with a root mean square error of approximation of 0.019, 90% confidence interval (CI) of 0.00-0.074, comparative fit index of 0.988, chi-square p = 0.393, and chi-square/df of 1.053.

CONCLUSIONS

Adolescent life-event stress is associated with elevated IL-6 and hepcidin concentration but not hypoferremia. These findings may help in iron supplementation programs for tackling anemia.

Effectiveness of treatment of iron deficiency anemia in rats with squid ink melanin-Fe

Iron deficiency anemia (IDA) is the one of the most common nutritional problems and is encountered all over the world. This study analysed the effects of squid ink melanin-Fe (SM-Fe) on IDA in rats. Forty weanling SD male rats were used and thirty-two rats were fed an iron-deficient diet for 4 weeks. Then SM-Fe (dosages of iron is 6 mg kg(-1) BW) was given to the IDA rats once a day for 3 weeks by intragastric administration, with FeCl3 and FeSO4 (dosages of iron is 6 mg kg(-1) BW) as positive controls. While the IDA model group and the control group were administrated distilled deionized water each day for 3 weeks. The content of haemoglobin (Hb), serum iron (SI), total iron binding capacity (TIBC), serum ferritin (SF), transferrin receptor (sTfR), erythropoietin (EPO), and iron content in the liver and spleen were measured. The results showed that the content of Hb, SI, SF, EPO, iron content in the liver and spleen were significantly increased in the iron supplement groups (SM-Fe, FeCl3 and FeSO4) compared with the model group (P < 0.05), while TIBC and sTfR were significantly decreased in the iron supplement groups compared with the model group (P < 0.05). In comparison with the FeCl3 and FeSO4 groups, a higher bioavailability of iron and fewer side effects were observed in the SM-Fe group. The present study indicated that SM-Fe is an effective source of iron supplement for IDA rats and might be exploited as a new iron fortifier.

Manipulation of the hepcidin pathway for therapeutic purposes

Hepcidin, the liver-produced peptide hormone, is a principal regulator of iron homeostasis. Abnormal hepcidin production has emerged as a causative factor in several common iron disorders. Hepcidin insufficiency results in iron overload in hereditary hemochromatosis and iron-loading anemias, whereas hepcidin excess causes or contributes to the development of iron-restricted anemias in inflammatory diseases, infections, some cancers and chronic kidney disease. Not surprisingly, hepcidin and related pathways have become the target for the development of novel therapeutics for iron disorders. In this review, we will summarize the strategies and development programs that have been devised for agonizing or antagonizing hepcidin and its receptor ferroportin.

Soluble transferrin receptor (sTfR) and sTfR/log ferritin index for the diagnosis of iron-deficiency anemia. A meta-analysis

Determination of serum soluble transferrin receptor (sTfR) is proposed to distinguish between iron-deficiency anemia and anemia of chronic disease. Here we conducted a meta-analysis of the literature to evaluate the diagnostic efficacy of sTfR and sTfR/log ferritin index. The meta-analysis included 18 sTfR and 10 sTfR index studies. Three sTfR index studies were, however, eliminated as outliers. The odds ratio was significant for both sTfR (22.9, 95% confidence interval [CI], 9.6-55.0) and sTfR index (9.5, 95% CI, 5.0-18.1) in a heterogeneous set of studies. Meta-analysis for sensitivity, specificity, and likelihood ratios (LRs) was performed only in a subset of 10 sTfR studies. The overall sensitivity, specificity, and positive and negative LRs were 86%, 75%, 3.85, and 0.19, respectively, with an area under summary receiver operating characteristic curve of 0.912 (standard error, 0.039). Additional studies are needed to define the overall diagnostic accuracy of sTfR.

Rethinking iron regulation and assessment in iron deficiency, anemia of chronic disease, and obesity: introducing hepcidin

Adequate iron availability is essential to human development and overall health. Iron is a key component of oxygen-carrying proteins, has a pivotal role in cellular metabolism, and is essential to cell growth and differentiation. Inadequate dietary iron intake, chronic and acute inflammatory conditions, and obesity are each associated with alterations in iron homeostasis. Tight regulation of iron is necessary because iron is highly toxic and human beings can only excrete small amounts through sweat, skin and enterocyte sloughing, and fecal and menstrual blood loss. Hepcidin, a small peptide hormone produced mainly by the liver, acts as the key regulator of systemic iron homeostasis. Hepcidin controls movement of iron into plasma by regulating the activity of the sole known iron exporter ferroportin-1. Downregulation of the ferroportin-1 exporter results in sequestration of iron within intestinal enterocytes, hepatocytes, and iron-storing macrophages reducing iron bioavailability. Hepcidin expression is increased by higher body iron levels and inflammation and decreased by anemia and hypoxia. Importantly, existing data illustrate that hepcidin may play a significant role in the development of several iron-related disorders, including the anemia of chronic disease and the iron dysregulation observed in obesity. Therefore, the purpose of this article is to discuss iron regulation, with specific emphasis on systemic regulation by hepcidin, and examine the role of hepcidin within several disease states, including iron deficiency, anemia of chronic disease, and obesity. The relationship between obesity and iron depletion and the clinical assessment of iron status will also be reviewed.

Imperfect gold standards for kidney injury biomarker evaluation

Clinicians have used serum creatinine in diagnostic testing for acute kidney injury for decades, despite its imperfect sensitivity and specificity. Novel tubular injury biomarkers may revolutionize the diagnosis of acute kidney injury; however, even if a novel tubular injury biomarker is 100% sensitive and 100% specific, it may appear inaccurate when using serum creatinine as the gold standard. Acute kidney injury, as defined by serum creatinine, may not reflect tubular injury, and the absence of changes in serum creatinine does not assure the absence of tubular injury. In general, the apparent diagnostic performance of a biomarker depends not only on its ability to detect injury, but also on disease prevalence and the sensitivity and specificity of the imperfect gold standard. Assuming that, at a certain cutoff value, serum creatinine is 80% sensitive and 90% specific and disease prevalence is 10%, a new perfect biomarker with a true 100% sensitivity may seem to have only 47% sensitivity compared with serum creatinine as the gold standard. Minimizing misclassification by using more strict criteria to diagnose acute kidney injury will reduce the error when evaluating the performance of a biomarker under investigation. Apparent diagnostic errors using a new biomarker may be a reflection of errors in the imperfect gold standard itself, rather than poor performance of the biomarker. The results of this study suggest that small changes in serum creatinine alone should not be used to define acute kidney injury in biomarker or interventional studies.

Prospective evaluation of the association between cardiac troponin T and markers of disturbed erythropoiesis in patients with heart failure

BACKGROUND

Elevated cardiac troponin T is a well-documented marker of cardiomyocyte damage and poor prognosis in patients with heart failure. We prospectively evaluated the relationship between this marker and hematopoietic disturbances in heart failure.

METHODS

Data were analyzed from 254 patients in the UNITE-HF Biomarker Registry, a prospective, observational, multicenter study of the clinical and biomarker correlates of anemia in heart failure. Logistic regression modeling assessed relationships between detectable troponin T and indices of hematologic function including anemia and red cell distribution width.

RESULTS

Anemia (hemoglobin≤12 g/dL) was present in 65 of the 254 study patients, and detectable troponin T was found in 39. Anemia was a significant independent predictor of detectable troponin T in models that considered a number of clinical characteristics including renal function, functional class, heart rate, and systolic blood pressure (odds ratio 2.57, 95% CI 1.09-6.09, P=.032). Likewise, detectable troponin T was directly and independently related to red cell distribution width in similar multivariable analyses (odds ratio 1.36 per unit increase, 95% CI 1.08-1.71, P=.008).

CONCLUSIONS

Anemia and increasing red cell distribution width were independently associated with elevated troponin T, a marker of cardiomyocyte injury or death in patients with heart failure.

Exact confidence interval estimation for the difference in diagnostic accuracy with three ordinal diagnostic groups

In the cases with three ordinal diagnostic groups, the important measures of diagnostic accuracy are the volume under surface (VUS) and the partial volume under surface (PVUS) which are the extended forms of the area under curve (AUC) and the partial area under curve (PAUC). This article addresses confidence interval estimation of the difference in paired VUS s and the difference in paired PVUS s. To focus especially on studies with small to moderate sample sizes, we propose an approach based on the concepts of generalized inference. A Monte Carlo study demonstrates that the proposed approach generally can provide confidence intervals with reasonable coverage probabilities even at small sample sizes. The proposed approach is compared to a parametric bootstrap approach and a large sample approach through simulation. Finally, the proposed approach is illustrated via an application to a data set of blood test results of anemia patients.

Assessment of iron status and the role for iron-replacement therapy in anaemic cancer patients under the care of a specialist palliative care unit

Anaemia is common in advanced cancer, may develop for several reasons, and is not always symptomatic. Our observations of the seemingly indiscriminate prescription of iron-replacement therapy (IRT) for anaemic palliative care patients, and our practice of discontinuing IRT in patients with normal red-cell indices, prompted a study to determine (1) the prevalence of anaemia in our patients, (2) what proportion had iron deficiency, (3) the prevalence and benefits of IRT and (4) the prevalence of side effects attributable to IRT. The prevalence of anaemia was 65%. We found a 9% prevalence of iron deficiency, and suggestive but inconclusive evidence of iron deficiency in a further 41%, but only three (27%) of these patients had typical iron deficiency red-cell indices. Only two patients within the study population were taking IRT. Haemoglobin increased significantly in one, but fell in the other, and both experienced side effects attributable to iron. IRT should neither be indiscriminately prescribed nor withheld for anaemic palliative care patients, and the decision should not be based on red-cell indices alone. When symptomatic anaemia is found in patients whose general condition indicates that IRT would be acceptable, iron status should be fully assessed. A therapeutic trial of IRT may be justified where ferritin is elevated, but other parameters suggest iron deficiency.

Malignant round cell neoplasia in llamas and alpacas

Malignant round cell neoplasia was identified in 12 llamas and 12 alpacas aged 0-23 years. Mean age of affected alpacas (3.1 years) was significantly less than that of affected llamas (8.0 years). Tumor cell morphology varied from large and often pleomorphic (11 tumors) to small and often homogeneous (13 tumors). Neoplastic lesions were multicentric in 12 cases. Other sites were gastric (5 cases), intra-abdominal (perirenal; 4 cases), intrathoracic (2 cases), and cervical (1 case). Immunohistochemistry with antibodies to CD79alpha, BLA36, and CD3 identified B-cell lymphoma (12 cases) and T-cell lymphoma (6 cases). Six tumors did not express any lymphoid marker and were further immunostained for neuron-specific enolase (NSE), synaptophysin, S-100, glial fibrillary acidic protein (GFAP), and chromogranin A. All 6 of these tumors were negative for GFAP and chromogranin A but expressed 1 or more of the neural markers NSE, synaptophysin, and S-100 and were classified as primitive malignant round cell tumors (PMRCT). Tumor types could not be distinguished on the basis of animal age, gross pathologic appearance, tumor morphology, or tumor location. All animals with lymphoma and 5 with PMRCT died or were euthanatized. One alpaca with a focal cervical PMRCT lived for at least 20 months after diagnosis. Results of this study indicate that malignant round cell tumors in llamas and alpacas are a heterogeneous group that cannot be distinguished on the basis of signalment, postmortem findings, or routine light microscopic findings. Immunohistochemistry is a valuable diagnostic procedure when evaluating malignant round cell neoplasia in llamas and alpacas.

Pediatric reference intervals for soluble transferrin receptor and transferrin receptor-ferritin index

BACKGROUND

Recent studies showing an improved diagnosis of iron deficiency (ID) with soluble transferrin receptor (sTfR) and sTfR-ferritin index did not take into account the age-dependency of sTfR and ferritin. Moreover, there is a paucity of data on pediatric reference intervals for sTfR and sTfR-ferritin index.

METHODS

A study cohort of 436 apparently healthy children was analyzed to establish reference intervals for ferritin, transferrin, sTfR and sTfR-ferritin index. To account for age-dependency, standard deviation scores (Z-scores) for these markers were calculated. The association between these parameters and C-reactive protein (CRP) was analyzed.

RESULTS

The Z-scores of ferritin, transferrin and sTfR had a significant association with CRP, whereas the Z-score of sTfR-ferritin did not correlate with CRP. The reference intervals of these parameters were reported.

CONCLUSION

Among the different markers of ID, the Z-scores of sTfR, transferrin and ferritin, but not sTfR-ferritin index, associate with the inflammatory status.

Red cell distribution width for assessment of activity of inflammatory bowel disease

BACKGROUND

Impaired iron absorption or increased loss of iron was found to correlate with disease activity and markers of inflammation in inflammatory bowel disease (IBD). Red cell distribution width (RDW) could be a reliable index of anisocytosis with the highest sensitivity to iron deficiency.

AIM

The importance of RDW in assessment of IBD disease activity is unknown. In this study, we aimed to determine if RDW could be useful in detecting active disease in patients with IBD.

MATERIALS AND METHODS

A total of 74 patients with ulcerative colitis (UC) and 22 patients with Crohn's disease (CD) formed the study group with 20 age- and sex-matched healthy volunteers as the control group. CD activity index higher than 150 in patients with CD was considered to indicate active disease. Patients with moderate and severe disease according to the Truelove-Witts scale were accepted as having active UC. In addition to RDW, serum C-reactive protein (CRP) and fibrinogen levels, erythrocyte sedimentation rates (ESR), leukocyte, and platelet counts were measured.

RESULTS

Fourteen (63.6%) of the patients with CD and 43 (58.1%) of the patients with UC had active disease. RDW, fibrinogen, CRP, ESR, and platelet counts were all significantly elevated in patients having active IBD compared with those without active disease and controls (P < 0.05). The study subjects were further classified into two subgroups: cases with active and inactive UC and those with active and inactive CD. A subgroup analysis indicated that for an RDW cutoff of 14, the sensitivity for detecting active UC was 88% and the specificity was 71% (area under curve [AUC] 0.81, P = 0.0001). RDW was the most sensitive and specific parameter indicating active UC. However, the same was not true for CD since CRP at a cutoff of 0.54 mg/dl showed a sensitivity of 92% and a specificity of 63% (AUC 0.92, P = 0.001), whereas RDW at a cutoff of 14.1 showed 78% sensitivity and 63% specificity to detect active CD.

CONCLUSION

Among the laboratory tests investigated, including fibrinogen, CRP, ESR, and platelet counts, receiver operating characteristic (ROC) curve analysis indicated RDW to be the most significant indicator of active UC. For CD, CRP was an important marker of active disease.

Serum transferrin receptor

Transferrin receptors (TfRs) are the conventional pathway by which cells acquire iron for physiological requirements. Under iron-deficient conditions there is an increased concentration of surface TfR, especially on bone marrow erythroid precursors, as a mechanism to sequester needed iron. TfRs are also present in the circulation, and the circulating serum TfR (sTfR) level reflects total body TfR concentration. Under normal conditions erythroid precursors are the main source of sTfR. Disorders of the bone marrow with reduced erythroid precursors are associated with low sTfR levels. The sTfR concentration begins to rise early in iron deficiency with the onset of iron-deficient erythropoiesis, and continues to rise as iron-deficient erythropoiesis progressively worsens, prior to the development of anemia. The sTfR level does not increase in anemia of chronic inflammation, but is increased when anemia of chronic inflammation is combined with iron deficiency. The sTfR level is also increased in patients with expanded erythropoiesis, including hemolytic anemias, myelodysplastic syndromes, and use of erythropoietic stimulating agents. The ratio of sTfR/ferritin can be used to quantify the entire spectrum of iron status from positive iron stores through negative iron balance, and is particularly useful in evaluating iron status in population studies. The sTfR/log ferritin ratio is valuable for distinguishing anemia of chronic inflammation from iron deficiency anemia, whether the latter occurs alone or in combination with anemia of chronic inflammation.

Intravenous Iron Therapy: A Summary of Treatment Options and Review of Guidelines

Iron replacement for iron-deficiency anemia has historically been accomplished with the use of oral iron therapy. Although oral iron is appropriate for most iron-deficiency anemia patients, many patients do not respond to or may be intolerant of oral iron, or may experience bleeding of sufficient magnitude to require higher iron doses than that achievable with oral iron. Intravenous iron therapy is a useful option for these latter patients. Three intravenous iron products are recommended: low-molecular weight iron dextran (INFeD), ferric gluconate (Ferrlecit), and iron sucrose (Venofer). These intravenous iron products have superior safety profiles compared to high-molecular weight iron dextran. The Food and Drug Administration's approval of erythropoietic-stimulating agents to treat certain types of anemia has increased usage of intravenous iron for functional iron deficiency. This review summarizes the current status of intravenous iron products and discusses their advantages and disadvantages in treating both absolute and functional iron deficiency.

Iron and anemia in human biology: a review of mechanisms

The biology of iron in relation to anemia is best understood by a review of the iron cycle, since the majority of iron for erythropoiesis is provided by iron recovered from senescent erythrocytes. In iron-deficiency anemia, storage iron declines until iron delivery to the bone marrow is insufficient for erythropoiesis. This can be monitored with clinical indicators, beginning with low plasma ferritin, followed by decreased plasma iron and transferrin saturation, and culminating in red blood cells with low-Hb content. When adequate dietary iron is provided, these markers show return to normal, indicating a response to the dietary supplement. Anemia of inflammation (also known as anemia of chronic disease, or ACD) follows a different course, because in this form of anemia storage iron is often abundant but not available for erythropoiesis. The diagnosis of ACD is more difficult than the diagnosis of iron-deficiency anemia, and often the first identified symptom is the failure to show a response to a dietary iron supplement. Confirmation of ACD is best obtained from elevated markers of inflammation. The treatment of ACD, which typically employs erythropoietin (EPO) supplements and intravenous iron (i.v.-iron), is empirical and often falls shorts of therapeutic goals. Dialysis patients show a complex pattern of anemia, which results from inadequate EPO production by the kidney, inflammation, changes in nutrition, and blood losses during treatment. EPO and i.v.-iron are the mainstays of treatment. Patients with heart failure can be anemic, with incidence as high as 50%. The causes are multifactorial; inflammation now appears to be the primary cause of this form of anemia, with contributions from increased plasma volume, effects of drug therapy, and other complications of heart disease. Discerning the mechanisms of anemia for the heart failure patient may aid rational therapy in each case.

Chronic anemia and fatigue in elderly patients: results of a randomized, double-blind, placebo-controlled, crossover exploratory study with epoetin alfa

OBJECTIVES

To evaluate the effect of epoetin alfa treatment on hemoglobin (Hb), fatigue, quality of life (QOL), and mobility in elderly patients with chronic anemia.

DESIGN

An exploratory, 32 week, randomized, double-blind, crossover treatment trial.

PARTICIPANTS

Sixty-two community-dwelling individuals aged 65 and older with chronic anemia (Hb < or =11.5 g/dL).

INTERVENTION

Subcutaneous epoetin alfa or placebo weekly for 16 weeks (Phase I) with crossover to the opposite treatment (Phase II).

MEASUREMENTS

Hb and QOL scores from the Functional Assessment of Chronic Illness Therapy (FACIT) measurement system. Mobility was assessed as a secondary outcome using the Timed Up and Go (TUG) test.

RESULTS

Of the 62 subjects enrolled, complete data were analyzed for 58 in Phase I and 54 participants in Phase II. Of those enrolled, most were African American (95%) and female (85%) and had multiple comorbidities and a mean age+/-standard deviation of 76.1+/-7.2. Mean baseline Hb was 10.5+/-0.9 g/dL (7.3-11.5). In Phase I, 67% of those taking epoetin alfa, and in Phase II, 69% of those taking epoetin alfa had an increase in Hb of more than 2 g/dL, significantly more than those taking placebo (P<.001). Similarly, elderly participants significantly improved on the fatigue and anemia subscales of the FACIT across phases (all P<.05). No significant differences were found between treatment and placebo on TUG scores. Epoetin alfa was well tolerated.

CONCLUSION

In this trial involving predominantly older African-American women with anemia, a direct relationship existed between increases in Hb during epoetin alfa therapy and improvements in fatigue and QOL.

Predicting iron and folate deficiency anaemias from standard blood testing: the mechanism and implications for clinical medicine and public health in developing countries

Background

Developing countries have high prevalence of diseases, but facilities to diagnose and treat them are limited. We must use available resources in ways not needed where there are sophisticated equipment and trained staff. Anaemia is common; iron deficiency affects health and productivity; folate deficiency in pregnant women causes foetal abnormalities. Few developing countries can measure serum folate or ferritin, but standard automated blood analyses are widely available and can help predict folate and iron deficiency. The RDW-CV% (coefficient of variation of the red cell width) measures the variability in the size of red blood cells (RBC) in routine automated analysis of blood cells, but is seldom reported. Levels of RDW-CV% and haemoglobin (Hb) can predict iron deficiency anaemia.

Method and results

I have written a computer model based on the standard mechanism for blood formation and destruction. This shows that before anaemia develops and during recovery, there are both normal and abnormal RBC (small in iron deficiency and large in folate deficiency) in the circulation. The model calculates the abnormality in the RDW-CV% in standard automated blood analyses. In early iron deficiency and during recovery the full blood count shows the Hb near the lower limit of normal, a low MCV and a high RDW-CV%. A similar pattern, but with a higher MCV, develops in folate deficiency. Folate deficiency is often brief and may not cause anaemia. The high RDW-CV% may persist for three months.

Conclusion

This long footprint could be medically useful for detecting folate deficiency and so limiting foetal damage in individuals and communities. Few clinicians or public health workers know about RDW-CV%. Standard blood reports for clinical use should include the RDW-CV% and note the possible significance of abnormal values.

Silent angiodysplasia and occult haemobilia as rare but treatable causes of refractory iron deficiency--two case reports

Once menorrhagia has been excluded in females then, in both sexes, the gastrointestinal tract remains the commonest site for haemorrhage. This may be of surprisingly large volume but intermittent and therefore not universally demonstrated on stool testing. However, if loss is persistent it may nevertheless culminate in absolute iron deficiency and thus, even when occult blood is not present on repeated examinations, quantitation using chromium labelled red cells becomes invaluable. In this situation, endoscopy or contrast radiology of the small and large bowel may fail to reveal any lesion even when these procedures are repeated or used in combination. Modifications by direct inspection or camera study may be helpful in improving diagnostic accuracy. It is nevertheless practical, as illustrated by these two cases, to more widely recognise the value of radionuclide scanning methods. In one this was due to unsuspected haemobilia and the second to major duodenal vascular malformation although it could be reasonably argued that initial recourse to angiography might have demonstrated this. The principle is that when precisely defined anatomically surgery can be elective and limited as a result of careful proactive planning and operations likely to have a high initial rate of success. The role of nuclear medicine in the investigative algorithm of such patient is re-emphasised. Thus, in any individual with unexplained but proven absolute iron deficiency failure to reveal the cause by first screening with gastroscopy and colonoscopy or barium studies including the small bowel should not automatically be repeated. Rather, the blood loss needs to be documented and, if possible, subsequent evaluation moved to advancement or push enteroscopy, capsule endoscopy or the more invasive angiography only once quantity a pattern of bleeding are defined by radioisoptic imaging.

An ROC-type measure of diagnostic accuracy when the gold standard is continuous-scale

ROC curves and summary measures of accuracy derived from them, such as the area under the ROC curve, have become the standard for describing and comparing the accuracy of diagnostic tests. Methods for estimating ROC curves rely on the existence of a gold standard which dichotomizes patients into disease present or absent. There are, however, many examples of diagnostic tests whose gold standards are not binary-scale, but rather continuous-scale. Unnatural dichotomization of these gold standards leads to bias and inconsistency in estimates of diagnostic accuracy. In this paper, we propose a non-parametric estimator of diagnostic test accuracy which does not require dichotomization of the gold standard. This estimator has an interpretation analogous to the area under the ROC curve. We propose a confidence interval for test accuracy and a statistical test for comparing accuracies of tests from paired designs. We compare the performance (i.e. CI coverage, type I error rate, power) of the proposed methods with several alternatives. An example is presented where the accuracies of two quick blood tests for measuring serum iron concentrations are estimated and compared.

ROC Curves in Clinical Chemistry: Uses, Misuses, and Possible Solutions

Background: ROC curves have become the standard for describing and comparing the accuracy of diagnostic tests. Not surprisingly, ROC curves are used often by clinical chemists. Our aims were to observe how the accuracy of clinical laboratory diagnostic tests is assessed, compared, and reported in the literature; to identify common problems with the use of ROC curves; and to offer some possible solutions.

Methods: We reviewed every original work using ROC curves and published in Clinical Chemistry in 2001 or 2002. For each article we recorded phase of the research, prospective or retrospective design, sample size, presence/absence of confidence intervals (CIs), nature of the statistical analysis, and major analysis problems.

Results: Of 58 articles, 31% were phase I (exploratory), 50% were phase II (challenge), and 19% were phase III (advanced) studies. The studies increased in sample size from phase I to III and showed a progression in the use of prospective designs. Most phase I studies were powered to assess diagnostic tests with ROC areas ≥0.70. Thirty-eight percent of studies failed to include CIs for diagnostic test accuracy or the CIs were constructed inappropriately. Thirty-three percent of studies provided insufficient analysis for comparing diagnostic tests. Other problems included dichotomization of the gold standard scale and inappropriate analysis of the equivalence of two diagnostic tests.

Conclusion: We identify available software and make some suggestions for sample size determination, testing for equivalence in diagnostic accuracy, and alternatives to a dichotomous classification of a continuous-scale gold standard. More methodologic research is needed in areas specific to clinical chemistry.

Soluble Transferrin Receptor and Soluble Transferrin Receptor-Ferritin Index for Evaluation of the Iron Status in Elderly Patients

We aimed to evaluate the diagnostic values of soluble transferrin receptor (sTfR) concentration, transferrin-ferritin index (soluble transferrin receptor concentration/log ferritin), ferritin levels and other related parameters in geriatric patients with anemia of chronic disease (ACD) and iron deficiency (IDA). Forty-four elderly subjects (median age 73 [63-94]) and twenty healthy subjects (median age 49 [44-56]) were enrolled into this study, divided into four groups: twenty middle aged healthy subjects (group A), fifteen elderly patients with IDA (group B), fourteen elderly patients with ACD (group C) and fifteen nonanemic geriatric subjects (group D). Hemoglobin, mean corpuscular volume, serum iron concentration and transferrin saturation levels of the patients in IDA group were found significantly lower than those in both non-anemic group and healthy subjects. Serum sTfR concentrations of the patients in IDA group were significantly higher than those in non-anemic geriatric group, ACD group and healthy subjects. Transferrin-ferritin index of the patients with IDA was significantly higher than that in non-anemic geriatric and ACD group. Serum ferritin levels of the patients in IDA group did not show any differences when compared with the other groups. Serum ferritin was highly specific for IDA (95%) when compared with ACD, although its sensitivity was low (38%). STfR values were negatively correlated with both transferrin and ferritin levels (p = 0.042 r = -0.40; and p = 0.034 r = -0.41, respectively). In conclusion, serum soluble transferrin receptor and transferrin-ferritin index may be used together with serum ferritin to distinguish the iron deficiency state in the elderly.