Detecting iron deficiency in anemic patients with concomitant medical problems

Prevalence of iron deficiency in patients admitted to a geriatric unit: a multicenter cross-sectional study

BACKGROUND

Iron deficiency (ID) is often associated with other comorbidities in older patients and is a factor of morbimortality. However, the prevalence of ID remains poorly documented in this population.

METHODS

The CARENFER PA study was a French multicenter cross-sectional study whose objective was to evaluate ID in patients (> 75 years) admitted to a geriatric unit. The primary endpoint was the ID prevalence defined as: serum ferritin < 100 µg/L and/or transferrin saturation coefficient (TSAT) < 20%. The Short Physical Performance Battery (SPPB) test was used to identify older patients at high risk of adverse events (e.g., disability, falls, hospitalization, death).

RESULTS

A total of 888 patients (mean age, 85.2 years; women, 63.5%) from 16 French centers were included from October 2022 to December 2022. The prevalence of ID was 57.6% (95% CI, 54.3-60.9) in the cohort of older patients (62.6% in anemic and 53.3% in non-anemic patients; p = 0.0062). ID prevalence increased significantly with the presence of more than three comorbidities (65.6% vs. 55.9%; p = 0.0274), CRP ≥ 12 mg/L (73.0% vs. 49.3%; p < 0.001) and treatment that may influence ID/anemia (60.5% vs. 49.6%; p = 0.0042). In multivariate analysis, only CRP ≥ 12 mg/L was an independent predictive factor of ID (odds ratio, 2.78; 95% CI, 1.92-4.08; p < 0.001). SPPB scores were low (0-6) in 60.5% of patients with ID versus 48.6% of patients without ID (p = 0.0076).

CONCLUSION

More than half of older patients had ID, including non-anemic patients. ID was associated with the presence of inflammation and a low SPPB score.

TRIAL REGISTRATION

NCT05514951.

Perioperative Quality Initiative and Enhanced Recovery After Surgery-Cardiac Society Consensus Statement on the Management of Preoperative Anemia and Iron Deficiency in Adult Cardiac Surgery Patients

Preoperative anemia is common in patients presenting for cardiac surgery, with a prevalence of approximately 1 in 4, and has been associated with worse outcomes including increased risk of blood transfusion, kidney injury, stroke, infection, and death. Iron deficiency, a major cause of anemia, has also been shown to have an association with worse outcomes in patients undergoing cardiac surgery, even in the absence of anemia. Although recent guidelines have supported diagnosing and treating anemia and iron deficiency before elective surgery, details on when and how to screen and treat remain unclear. The Eighth Perioperative Quality Initiative (POQI 8) consensus conference, in conjunction with the Enhanced Recovery after Surgery-Cardiac Surgery Society, brought together an international, multidisciplinary team of experts to review and evaluate the literature on screening, diagnosing, and managing preoperative anemia and iron deficiency in patients undergoing cardiac surgery, and to provide evidence-based recommendations in accordance with Grading of Recommendations, Assessment, Development and Evaluation (GRADE) criteria for evaluating biomedical literature.

Serum or plasma ferritin concentration as an index of iron deficiency and overload

BACKGROUND

Reference standard indices of iron deficiency and iron overload are generally invasive, expensive, and can be unpleasant or occasionally risky. Ferritin is an iron storage protein and its concentration in the plasma or serum reflects iron stores; low ferritin indicates iron deficiency, while elevated ferritin reflects risk of iron overload. However, ferritin is also an acute-phase protein and its levels are elevated in inflammation and infection. The use of ferritin as a diagnostic test of iron deficiency and overload is a common clinical practice.

OBJECTIVES

To determine the diagnostic accuracy of ferritin concentrations (serum or plasma) for detecting iron deficiency and risk of iron overload in primary and secondary iron-loading syndromes.

SEARCH METHODS

We searched the following databases (10 June 2020): DARE (Cochrane Library) Issue 2 of 4 2015, HTA (Cochrane Library) Issue 4 of 4 2016, CENTRAL (Cochrane Library) Issue 6 of 12 2020, MEDLINE (OVID) 1946 to 9 June 2020, Embase (OVID) 1947 to week 23 2020, CINAHL (Ebsco) 1982 to June 2020, Web of Science (ISI) SCI, SSCI, CPCI-exp & CPCI-SSH to June 2020, POPLINE 16/8/18, Open Grey (10/6/20), TRoPHI (10/6/20), Bibliomap (10/6/20), IBECS (10/6/20), SCIELO (10/6/20), Global Index Medicus (10/6/20) AIM, IMSEAR, WPRIM, IMEMR, LILACS (10/6/20), PAHO (10/6/20), WHOLIS 10/6/20, IndMED (16/8/18) and Native Health Research Database (10/6/20). We also searched two trials registers and contacted relevant organisations for unpublished studies.

SELECTION CRITERIA

We included all study designs seeking to evaluate serum or plasma ferritin concentrations measured by any current or previously available quantitative assay as an index of iron status in individuals of any age, sex, clinical and physiological status from any country.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methods. We designed the data extraction form to record results for ferritin concentration as the index test, and bone marrow iron content for iron deficiency and liver iron content for iron overload as the reference standards. Two other authors further extracted and validated the number of true positive, true negative, false positive, false negative cases, and extracted or derived the sensitivity, specificity, positive and negative predictive values for each threshold presented for iron deficiency and iron overload in included studies. We assessed risk of bias and applicability using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool. We used GRADE assessment to enable the quality of evidence and hence strength of evidence for our conclusions.

MAIN RESULTS

Our search was conducted initially in 2014 and updated in 2017, 2018 and 2020 (10 June). We identified 21,217 records and screened 14,244 records after duplicates were removed. We assessed 316 records in full text. We excluded 190 studies (193 records) with reasons and included 108 studies (111 records) in the qualitative and quantitative analysis. There were 11 studies (12 records) that we screened from the last search update and appeared eligible for a future analysis. We decided to enter these as awaiting classification. We stratified the analysis first by participant clinical status: apparently healthy and non-healthy populations. We then stratified by age and pregnancy status as: infants and children, adolescents, pregnant women, and adults. Iron deficiency We included 72 studies (75 records) involving 6059 participants. Apparently healthy populations Five studies screened for iron deficiency in people without apparent illness. In the general adult population, three studies reported sensitivities of 63% to 100% at the optimum cutoff for ferritin, with corresponding specificities of 92% to 98%, but the ferritin cutoffs varied between studies. One study in healthy children reported a sensitivity of 74% and a specificity of 77%. One study in pregnant women reported a sensitivity of 88% and a specificity of 100%. Overall confidence in these estimates was very low because of potential bias, indirectness, and sparse and heterogenous evidence. No studies screened for iron overload in apparently healthy people. People presenting for medical care There were 63 studies among adults presenting for medical care (5042 participants). For a sample of 1000 subjects with a 35% prevalence of iron deficiency (of the included studies in this category) and supposing a 85% specificity, there would be 315 iron-deficient subjects correctly classified as having iron deficiency and 35 iron-deficient subjects incorrectly classified as not having iron deficiency, leading to a 90% sensitivity. Thresholds proposed by the authors of the included studies ranged between 12 to 200 µg/L. The estimated diagnostic odds ratio was 50. Among non-healthy adults using a fixed threshold of 30 μg/L (nine studies, 512 participants, low-certainty evidence), the pooled estimate for sensitivity was 79% with a 95% confidence interval of (58%, 91%) and specificity of 98%, with a 95% confidence interval of (91%, 100%). The estimated diagnostic odds ratio was 140, a relatively highly informative test. Iron overload We included 36 studies (36 records) involving 1927 participants. All studies concerned non-healthy populations. There were no studies targeting either infants, children, or pregnant women. Among all populations (one threshold for males and females; 36 studies, 1927 participants, very low-certainty evidence): for a sample of 1000 subjects with a 42% prevalence of iron overload (of the included studies in this category) and supposing a 65% specificity, there would be 332 iron-overloaded subjects correctly classified as having iron overload and 85 iron-overloaded subjects incorrectly classified as not having iron overload, leading to a 80% sensitivity. The estimated diagnostic odds ratio was 8.

AUTHORS' CONCLUSIONS

At a threshold of 30 micrograms/L, there is low-certainty evidence that blood ferritin concentration is reasonably sensitive and a very specific test for iron deficiency in people presenting for medical care. There is very low certainty that high concentrations of ferritin provide a sensitive test for iron overload in people where this condition is suspected. There is insufficient evidence to know whether ferritin concentration performs similarly when screening asymptomatic people for iron deficiency or overload.

Sensitivity and specificity of the mean corpuscular volume and CD4/CD8 ratio in discriminating between rifampicin resistant and rifampicin sensitive tuberculosis

Background

There is need for simple, cost effective and widely available point of care tests for low level health facilities in developing countries to screen for drug resistant tuberculosis (TB) after bacteriological confirmation of TB by smear microscopy. We evaluated the sensitivity and specificity of the mean corpuscular volume (MCV) and CD4/CD8 ratio in discriminating between rifampicin resistant (RR-TB) and rifampicin sensitive (RS-TB) tuberculosis.

Methods

We performed a secondary analysis of data from a cross sectional study that enrolled adult participants with bacteriologically confirmed pulmonary TB at a national tuberculosis treatment center in Uganda. Blood samples were tested for CD4 and CD8 cell counts, HIV serology and a full hemogram. Rifampicin sensitivity and the bacillary load grade were determined by Xpert MTB/RIF®. Fifty-five participants that had RR-TB (cases) were matched with 110 participants that had RS-TB (controls) for age, sex and HIV status in a ratio of 1:2 respectively. Sensitivity (Se), specificity (Sp), area under curve (AUC) analysis and determination of optimal cut-offs were performed using receiver operating characteristic curves.

Results

Cases differed from controls with respect to residence (p = 0.031), bacillary load grade (p < 0.010) and MCV (p = 0.021). The Se, Sp and AUC of the MCV (cut-off of > 74.6 femtolitres (fl)) were 88.9%, 34% and 0.607 (p = 0.021) respectively for RR-TB. Among HIV positive participants, the respective Se, Sp and AUC of the MCV for RR-TB (cut-off of > 72.5 fl) were 97.2%, 22.2% and 0.608 (p = 0.061). The respective Se, Sp and AUC of the CD4/CD8 ratio (cut-off of > 0.40) were 67.3%, 50.0% and 0.559 (p = 0.199) on the overall and 54.1%, 71.6% and 0.628 (p = 0.024) among the HIV positive participants for RR-TB.

Conclusion

The MCV had a high sensitivity but very low specificity for RR-TB. The CD4/CD8 ratio had a low sensitivity and specificity for RR-TB among HIV positive individuals. The utility of either test is low due to low diagnostic accuracy.

[Brain teasers in pruritus-when laboratory tests will guide you]

Chronic pruritus is a symptom of many systemic diseases. In contrast to dermatological pruritus, there are no primary changes in skin appearance. Establishing the correct diagnosis in these cases can be quite challenging. In some instances, laboratory tests can be helpful. This report highlights the importance of specific and target-orientated laboratory tests in four patients with chronic pruritus due to systemic diseases.

Diagnosis of anemia-A synoptic overview and practical approach

Anemia is common in everyday clinical practice. In the following, the characteristics of apparently proven as well as new biomarkers are presented - for diagnosis and therapy control, considering their diagnostic value. In spite of new diagnostic tools, the importance of microscopy in hematological manifestations is illustrated. Based on a classification of anemia, a strategy is proposed for an economic diagnosis of different types of anemia and their predisposition.

Upper and lower gastrointestinal endoscopies in patients over 85 years of age: Risk-benefit evaluation of a longitudinal cohort

After age 85, upper and lower gastrointestinal (GI) endoscopy may be indicated in 5% to 10% of inpatients, but the risk-benefit ratio is unknown. We studied patients older than 85 years undergoing upper and lower GI endoscopy.We analyzed a retrospective cohort of inpatients older than 85 years between 2004 and 2012, all explored by upper and complete lower GI endoscopy. Initial indications, including iron deficiency anemia (IDA), other anemias, GI bleeding, weight loss, and GI symptoms, were noted, as were endoscopy or anesthesia complications, immediate endoscopic diagnosis, and the ability to modify the patients' therapeutics. Deaths and final diagnosis for initial endoscopic indication were analyzed after at least 12 months.We included 55 patients, 78% women, with a median age, reticulocyte count, hemoglobin, and ferritin levels of 87 (85-99), 56 (24-214) g/L, 8.6 (4.8-12.9) g/dL, and 56 (3-799) μg/L, respectively. IDA was the most frequent indication for endoscopy (60%; n = 33). Immediate diagnoses were found in 64% of the patients (n = 35), including 25% with GI cancers (n = 14) and 22% with gastroduodenal ulcers or erosions (n = 12). Cancer diagnosis was associated with lower reticulocyte count (45 vs. 60 G/L; P = .02). Among the 35 diagnoses, 94% (n = 33) led to modifications of the patients' therapeutics, with 29% of the patients deciding on palliative care (n = 10). No endoscopic complications lead to death. Follow-up of >12 months was available in 82% (n = 45) of the patients; among these patients, 40% (n = 27) died after an average 24 ± 18 months. Cancer diagnosis was significantly associated with less ulterior red cell transfusion (0% vs. 28%; P = .02) and fewer further investigations (6.7% vs. 40%; P = .02).Upper and complete lower GI endoscopy in patients older than 85 years appears to be safe, and enables a high rate of immediate diagnosis, with significant modifications of therapeutics. GI cancers represented more than one-third of the endoscopic diagnoses.

Ability of serum ferritin to diagnose iron deficiency anemia in an elderly cohort

Background

Diagnosis and treatment of iron deficiency anemia in older subjects improves their quality of life. Serum ferritin as a marker of iron stores is an acute phase protein. In older subjects who usually have many concomitant chronic medical conditions, serum ferritin may increase in response to inflammatory processes irrespective of iron stores. This study was performed to determine the diagnostic properties of serum ferritin in the diagnosis of iron deficiency anemia in older subjects.

Methods

This case–control study included all the inhabitants of Amirkola town who participated in the Amirkola Health and Aging Project. Diagnosis of anemia was confirmed based on a hemoglobin level <13 g/dL in men and <12 g/dL in women and iron deficiency anemia by percent transferrin saturation <15%. A receiver operating characteristic curve was constructed to determine an optimal serum ferritin cutoff value to differentiate patients with and without iron deficiency anemia at the highest sensitivity and specificity.

Results

Eighty patients with iron deficiency anemia and 160 cases of anemia without iron deficiency (mean age: 72.9 ± 8 and 71.6 ± 7.6 years, respectively; p-value = 0.37) were analyzed. In iron deficiency anemia, the mean serum ferritin was significantly lower (p-value = 0.036) compared to patients without iron deficiency anemia. Serum ferritin with a cutoff level of 100 ng/mL differentiated patients with and without iron deficiency anemia with a sensitivity of 60% and specificity of 59% and area under the receiver operating characteristic curve of 0.615 ± 0.040 (95% confidence interval: 0.536–0.694; p-value = 0.004).

Conclusion

These findings indicate that in elderly subjects, iron deficiency anemia may develop with higher levels of serum ferritin. Hence, the conventional cutoff of serum ferritin for the diagnosis of iron deficiency anemia in young adults is not appropriate for the elderly population.

Primary care requests for anaemia chemistry tests in Spain: potential iron, transferrin and folate over-requesting

Aim

To study the regional variability of requests for anaemia chemistry tests in primary care in Spain and the associated economic costs of potential over-requesting.

Methods

Requests for anaemia tests were examined in a cross-sectional study. Clinical laboratories from different autonomous communities (AACCs) were invited to report on primary care anaemia chemistry tests requested during 2014. Demand for iron, ferritin, vitamin B12 and folate tests per 1000 inhabitants and the ratios of the folate/vitamin B12 and transferrin/ferritin requests were compared between AACCs. We also calculated reagent costs and the number of iron, transferrin and folate tests and the economic saving if every AACC had obtained the results achieved by the AACC with best practice.

Results

110 laboratories participated (59.8% of the Spanish population). More than 12 million tests were requested, resulting in reagent costs exceeding €16.5 million. The serum iron test was the most often requested, and the ferritin test was the most costly (over €7 million). Close to €4.5 million could potentially have been saved if iron, transferrin and folate had been appropriately requested (€6 million when extrapolated to the whole Spanish population).

Conclusions

The demand for and expenditure on anaemia chemistry tests in primary care in Spain is high, with significant regional differences between different AACCs.

Correlation between serum ferritin and bone marrow iron stores

Bone marrow aspirate examination is a gold standard to assess bone marrow iron stores. The correlation between serum ferritin and bone marrow iron has not been established in detail, as the cutoff value for iron stores have not been uniformly established. Ours was a cross-sectional study. Perl's Prussian blue stain was used to stain bone marrow, assessed by Gale's grading. Receiver operating characteristic curve analysis and Spearman's correlation coefficient calculated. Gale's grading revealed iron store deficiency in 26 and sufficiency in 13. Spearman's correlation coefficient of 0.90 showed a significant relation between serum ferritin and bone marrow iron stores. A serum ferritin of 228 pmol/L had high sensitivity and specificity for iron deficiency; our study suggests that this level be taken as the cutoff value to predict iron store deficiency in bone marrow.

Diagnosis of Iron Deficiency in Inflammatory Bowel Disease by Transferrin Receptor-Ferritin Index

Iron deficiency is common in patients with inflammatory bowel disease (IBD), but can be difficult to diagnose in the presence of inflammation because ferritin is an acute phase reactant. The transferrin receptor-ferritin index (TfR-F) has a high sensitivity and specificity for iron deficiency diagnosis in chronic diseases. The diagnostic efficacy of TfR-F is little known in patients with IBD. The aim of the study was to assess the added value of TfR-F to iron deficiency diagnosis in a prospective cohort of patients with IBD.Consecutive IBD patients were prospectively enrolled. Patients were excluded in case of blood transfusion, iron supplementation, or lack of consent. IBD activity was assessed on markers of inflammation (C-reactive protein, endoscopy, fecal calprotectin). Hemoglobin, ferritin, vitamin B9 and B12, Lactate dehydrogenase, haptoglobin, and soluble transferrin receptor (sTfR) were assayed. TfR-F was calculated as the ratio sTfR/log ferritin. Iron deficiency was defined by ferritin <30 ng/mL or TfR-F >2 in the presence of inflammation.One-hundred fifty patients with median age 38 years (16-78) and Crohn disease (n = 105), ulcerative colitis (n = 43), or unclassified colitis (n = 2) were included. Active disease was identified in 45.3%. Anemia was diagnosed in 28%. Thirty-six patients (24%) had ferritin <30 ng/mL. Thirty-two patients (21.3%) had ferritin levels from 30 to 100 ng/ml and inflammation: 2 had vitamin B12 deficiency excluding TfR-F analysis, 13 of 30 (43.3%) had TfR-F >2. Overall, iron deficiency was diagnosed in 32.7% of the patients.TfR-F in addition to ferritin <30 ng/mL criterion increased by 36% diagnosis rates of iron deficiency. TfR-F appeared as a useful biomarker that could help physicians to diagnose true iron deficiency in patients with active IBD.

Diagnosing anemia in inflammatory bowel disease: beyond the established markers

The main types of anemia in inflammatory bowel disease (IBD) are iron deficiency anemia (IDA) and anemia of inflammatory etiology, or anemia of chronic disease (ACD). In the management of IBD patients with anemia it is essential for the physician to diagnose the type of anemia in order to decide in an evidence-based manner for the appropriate treatment. However, the assessment of iron status in IBD in many cases is rather difficult due to coexistent inflammation. For this assessment several indices and markers have been suggested. Ferritin, seems to play a central role in the definition and diagnosis of anemia in IBD and transferrin, transferrin saturation (Tsat), and soluble transferrin receptors are also valuable markers. All these biochemical markers have several limitations because they are not consistently reliable indices, since they are influenced by factors other than changes in iron balance. In this review, in addition to them, we discuss the newer alternative markers for iron status that may be useful when serum ferritin and Tsat are not sufficient. The iron metabolism regulators, hepcidin and prohepcidin, are still under investigation in IBD. Erythrocytes parameters like the red cell distribution width (RDW) and the percentage of hypochromic red cells as well as reticulocyte parameters such as hemoglobin concentration of reticulocytes, red blood cell size factor and reticulocyte distribution width could be useful markers for the evaluation of anemia in IBD.

Urinary hepcidin level as an early predictor of iron deficiency in children: A case control study

Background

The ideal screening test would be capable of identifying iron deficiency in the absence of anemia. We tried to detect role of urinary hepcidin-25 level in early prediction of iron deficiency in children.

Methods

This is a case control study performed on 100 children in Hematology Unit of Pediatric Department, Zagazig University Hospital, Egypt. Our study included 25 cases of iron deficiency (ID) stage-1 (iron depletion), 25 cases ID stage-2 (iron-deficient erythropoiesis), 25 cases ID stage-3 (iron deficiency anemia) and 25 healthy children as a control group. Estimation of iron status parameters was done. Urinary hepcidin-25 level was detected.

Results

Urinary hepcidin-25 level was significantly lower in all stages of iron deficiency than in control group, more significant reduction in its level was observed with the progress in severity of iron deficiency. Urinary hepcidin showed significant positive correlation with hemoglobin, mean corpuscular volume, hematocrit value, serum iron and ferritin and transferrin saturation. In contrary, it showed significant negative correlation with serum transferrin and total iron binding capacity.

Urinary hepcidin at cutoff point ≤0.94 nmol/mmol Cr could Predict ID stage-1 with sensitivity 88% and specificity 88%. Cutoff point ≤0.42 nmol/mmol Cr could predict ID stage-2 with sensitivity 96% and specificity 92%. Cutoff point ≤0.08 nmol/mmol Cr could Predict ID stage-3 with Sensitivity 96% and specificity 100%.

Conclusions

We can conclude that detection of urinary hepcidin-25 level was a simple and non invasive test and could predict iron deficiency very early, before appearance of hematological affections.

Evaluation and treatment of iron deficiency anemia: a gastroenterological perspective

A substantial volume of the consultations requested of gastroenterologists are directed towards the evaluation of anemia. Since iron deficiency anemia often arises from bleeding gastrointestinal lesions, many of which are malignant, establishment of a firm diagnosis usually obligates an endoscopic evaluation. Although the laboratory tests used to make the diagnosis have not changed in many decades, their interpretation has, and this is possibly due to the availability of extensive testing in key populations. We provide data supporting the use of the serum ferritin as the sole useful measure of iron stores, setting the lower limit at 100 microg/l for some populations in order to increase the sensitivity of the test. Trends of the commonly obtained red cell indices, mean corpuscular volume, and the red cell distribution width can provide valuable diagnostic information. Once the diagnosis is established, upper and lower gastrointestinal endoscopy is usually indicated. Nevertheless, in many cases a gastrointestinal source is not found after routine evaluation. Additional studies, including repeat upper and lower endoscopy and often investigation of the small intestine may thus be required. Although oral iron is inexpensive and usually effective, there are many gastrointestinal conditions that warrant treatment of iron deficiency with intravenous iron.

Iron deficiency anemia

The most severe consequence of iron depletion is iron deficiency anemia (IDA), and it is still considered the most common nutrition deficiency worldwide. Although the etiology of IDA is multifaceted, it generally results when the iron demands by the body are not met by iron absorption, regardless of the reason. Individuals with IDA have inadequate intake, impaired absorption or transport, physiologic losses associated with chronological or reproductive age, or chronic blood loss secondary to disease. In adults, IDA can result in a wide variety of adverse outcomes including diminished work or exercise capacity, impaired thermoregulation, immune dysfunction, GI disturbances, and neurocognitive impairment. In addition, IDA concomitant with chronic kidney disease or congestive heart failure can worsen the outcome of both conditions. In this review, the prevalence of IDA related to confounding medical conditions will be described along with its diverse etiologies. Distinguishing IDA from anemia of chronic disease using hematologic measures is reviewed as well. In addition, current diagnostic strategies that are inclusive of clinical presentation, biochemical tests, and differential diagnosis will be outlined, followed by a discussion of treatment modalities and future research recommendations.

Bariatric surgery can correct iron depletion in morbidly obese women: a link with chronic inflammation

BACKGROUND

Obesity is associated with a chronic and low-grade inflammation which may cause hypoferremia as seen in patients with chronic inflammatory diseases. The aim of the present study was to investigate the relationship between iron status and markers of inflammation in morbidly obese women and the effect of bariatric surgery.

METHODS

Our cohort of patients consisted of 178 morbidly obese females selected for bariatric surgery. Clinical and biochemical data were recorded before surgery, and histopathological studies were carried out on preoperative liver biopsy samples. Fifty-five patients have been followed up after bariatric surgery.

RESULTS

A high prevalence of iron depletion was present in this cohort, with 53% having a transferrin saturation ratio below 0.20. Iron depletion was significantly correlated with raised levels of indices of inflammation, C-reactive protein (CRP), orosomucoid and haptoglobin), and with the white blood cell count. In multivariate analysis, orosomucoid and CRP were independently associated with iron depletion. Moreover, 6 months after bariatric surgery, inflammation level decreased, which was inversely correlated with the increase in transferrin saturation.

CONCLUSIONS

Iron depletion is common in morbidly obese women. Low-grade chronic inflammation associated with obesity could be a modulator of iron uptake and utilization. Bariatric surgery may reduce chronic inflammation and improve iron status.

Interpreting tests for iron deficiency among adults in a high HIV prevalence African setting: routine tests may lead to misdiagnosis

We evaluated peripheral blood tests to diagnose iron deficiency on medical wards in Blantyre, Malawi, where infection and HIV are prevalent. We compared full blood count, ferritin and serum transferrin receptor (TfR) levels with an estimation of iron in bone marrow aspirates. Of consecutive adults admitted with severe anaemia (haemoglobin <7 g/dl), 81 had satisfactory bone marrow aspirates. The main outcome measures were the validity of each test (sensitivity, specificity, and positive and negative predictive values) and likelihood ratios (LR) for iron deficiency. Twenty patients (25%) were iron deficient and 64 (79%) were HIV-positive. Iron deficiency was more common in HIV-negative compared with HIV-positive patients (59% vs. 16%; P<0.001). In HIV-positive patients, the optimal ferritin cut-off was 150 microg/l (sensitivity 20%, specificity 93%, LR 2.7), but no test was accurate enough to be clinically useful. In HIV-negative patients, ferritin was the single most accurate test (cut-off <70 microg/l, 100% specificity, 90% sensitive, LR if positive infinity, LR if negative 10). TfR measurement did not improve the accuracy. Mean cell volume was not a good predictor of iron status except in HIV-negative patients (cut-off <85 fl, specificity 71%, sensitivity 90%). In populations with high levels of infection and HIV, an HIV test is necessary to interpret any tests of iron deficiency. In HIV-negative patients, ferritin is the best blood test for iron deficiency, using a higher cut-off than usual. For HIV-positive patients, it is difficult to diagnose iron deficiency without bone marrow aspirates.

Should patients with anemia and low normal or normal serum ferritin undergo colonoscopy?

BACKGROUND

Patients with unexplained iron deficiency anemia have a greater prevalence of colonic neoplasia, and should be evaluated for a colonoscopy. The approach to patients with anemia without iron deficiency remains unclear.

OBJECTIVE

To compare the prevalence of colonic neoplasia in anemic patients with normal ferritin (>50 ng/mL), to those with ferritin < or =50 ng/mL, and nonanemic individuals.

METHODS

Patients referred for colonoscopy for anemia evaluation were stratified into 3 groups: ferritin < or =50 ng/mL, 51-100 ng/mL, and >100 ng/mL. We compared these groups to each other, and to asymptomatic nonanemic individuals undergoing screening colonoscopy. The prevalence of advanced colonic neoplasia was determined for each group using existing records.

RESULTS

During the study period, 414 patients who underwent colonoscopy for anemia evaluation and 323 nonanemic individuals who underwent colonoscopy for cancer screening met inclusion criteria. Study subjects were mostly men. The prevalence of advanced colonic neoplasia in subjects with ferritin 51-100 ng/mL was 7.2% (95% CI 2.4-17.9%), similar to 7.9% (95% CI 5.1-11.9%) in those with ferritin < or =50 ng/mL. The incidence of advanced colonic neoplasia in subjects with ferritin >100 ng/mL was 1.7% (95% CI 0.1-6.6%), similar to 1.2% (95% CI 0.4-3.3%) in the asymptomatic nonanemic group. After adjusting for age, patients with ferritin < or =50 ng/mL and 51-100 ng/mL were almost 5 times more likely to harbor advanced colonic neoplasia than the other groups. The addition of other laboratory parameters did not improve the predictive value of ferritin.

CONCLUSION

A ferritin cutoff of 100 ng/mL can be used to determine the need for colonoscopy in men with anemia.

Management of iron deficiency in patients admitted to hospital: time for a rethink of treatment principles

BACKGROUND

Iron deficiency is very common in patients admitted to hospital. Its management is changing with new insights into iron absorption and therapeutic options.

AIMS

The aims of this study were to develop guidelines for the correction of iron deficiency in patients admitted to hospital and to compare these with current practice.

METHODS

Based on current published evidence, guidelines were developed. All patients in whom iron deficiency was detected during hospital admission over a 2.5 year period were retrospectively studied. Their management was compared with that of the guidelines developed.

RESULTS

Three clinical scenarios were identified--(A) urgent attention to haemoglobin required: blood transfusion followed by i.v. iron recommended, (B) Semiurgent iron repletion: i.v. iron recommended and (C) non-urgent iron repletion: oral or i.v. repletion recommended. A total of 119 patients was identified, age 18-99 (median 77) years, 29% men, and haemoglobin 33-130 (87) g/L. Of 66 given blood transfusion, 17 had subsequent i.v. iron, 25 oral iron and 24 no other form of iron repletion. Of the other 53, nine had i.v. iron, 32 oral iron and 12 had no treatment. Fifty-five per cent of patients were managed according to the proposed guidelines and this occurred less frequently (9%) in those presenting with cardiovascular problems than in those with anaemia, gastrointestinal bleeding or other medical problems (all >60%; P < 0.0001, Fisher's exact test).

CONCLUSION

Current management is haphazard, with underutilization of i.v. iron and failure to initiate any regimen for iron repletion being common. It may be time for a change in approach to repletion of iron in ill patients.

Gastrointestinal endoscopic findings in men with unexplained anemia and low normal ferritin values

BACKGROUND

Most practice guidelines recommend endoscopic evaluation of the gastrointestinal (GI) tract in men and postmenopausal women with anemia and a serum ferritin less than 20-40 ng/ml. The diagnostic yield of endoscopy in patients with anemia, no GI symptoms or signs, and low normal ferritin is not known.

OBJECTIVE

The aim of this study was to investigate the yield of upper and lower GI endoscopic evaluations in anemic patients with ferritin levels between 40 and 100 ng/ml.

DESIGN

A retrospective review of patients' charts was conducted.

SUBJECTS AND METHODS

Patients at the Veterans Affairs Connecticut Healthcare System who underwent GI endoscopic evaluation for the sole indication of anemia and ferritin in the low normal range (40-100 ng/ml) were included in this study.

MEASUREMENTS

Incidence of pathology of the upper and lower GI tract was determined.

RESULTS

We identified 54 male patients who had a ferritin level of 40-100 ng/ml and no GI symptoms or known GI bleeding. Upper GI findings (malignancy, peptic ulcers, Helicobacter pylori gastritis, arteriovenous malformations) were found in 14/47 cases (30%). Lower gastrointestinal findings, including large tubular adenomas and arteriovenous malformation, were identified in 3/53 cases (6.7%).

CONCLUSION

Our study supports GI endoscopy in anemic patients with ferritin between 40 and 100 ng/ml, even in the absence of GI symptoms or documented bleeding.

Soluble transferrin receptor in hemochromatosis patients during phlebotomy therapy

BACKGROUND

The monitoring of phlebotomies in hemochromatosis patients depends on iron status measured by ferritin and transferrin saturation (TS). However, in the presence of inflammation or liver injury, soluble transferrin receptor (sTfR) determination was proposed to replace ferritin for diagnosing iron deficiency (ID). The present study evaluated performances of sTfR for the prediction of iron deficiency in a large number of hemochromatosis patients under phlebotomy therapy.

METHODS

We studied 52 patients undergoing therapeutic phlebotomies and obtained 2 samples from 37 patients. Biological parameters were determined before each phlebotomy began. Performances of sTfR and TS in the diagnosis of iron deficiency were compared, according to ferritin levels under 12 microg/l.

RESULTS

Ferritin and TS were correlated with removed iron (r=0.473, p<0.005 and r=0.345, p<0.05, respectively) and sTfR was correlated with the decrease in hemoglobin levels induced by phlebotomies (r=-0.678, p<0.0001). Areas under Receiver Operating Characteristics (ROC) curves for sTfR and TS were not statistically different for prediction of iron deficiency and sensitivity/specificity of sTfR at 1.64 mg/l were 67/86%.

CONCLUSIONS

sTfR determination could be used to predict iron depletion induced by phlebotomies when ferritin is of limited interest, to avoid the appearance of anemia.

Biology of anemia, differential diagnosis, and treatment options in human immunodeficiency virus infection

Anemia is the most common hematologic manifestation of human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome. The causes of HIV-related anemia are multifactorial and include direct and indirect effects of HIV infection. HIV-related anemia generally is due to reduced red blood cell (RBC) production, secondary to a variety of causes, but it may also involve nutritional deficiencies, increased RBC destruction, or a combination of these problems. Evaluation of hemoglobin level, reticulocyte count, bilirubin, and mean corpuscular volume value and review of the peripheral blood smear are necessary for diagnosis. Treatment of HIV-related anemia should address the correctable underlying causes of this disorder, such as modifications of offending medications, nutritional deficiencies, and parvovirus infection. Patients with HIV infection have a blunted erythropoietin response to anemia. Therapeutic modalities for anemia that is not amenable to correction include blood transfusion and recombinant human erythropoietin (epoetin alfa).