The Role of the Trabecular Bone Score in the Assessment of Osteoarticular Disorders in Patients with HFE-Hemochromatosis: A Single-Center Study from Poland.

Type 1 hereditary hemochromatosis (HH) is an autosomal, recessive genetic entity with systemic iron overload. Iron homeostasis disorders develop as a result of HFE gene mutations, which are associated with hepcidin arthropathy or osteoporosis and may cause permanent disability in HH patients despite a properly conducted treatment with phlebotomies. In this study, selected parameters of calcium and phosphate metabolism were analyzed in combination with the assessment of bone mineral density (BMD) disorders in patients from northern Poland with clinically overt HFE-HH. BMD was determined by a dual-energy X-ray absorptiometry (DXA) test with the use of the trabecular bone score (TBS) function. The study included 29 HH patients (mean age = 53.14 years) who were compared with 20 healthy volunteers. A significantly lower TBS parameter and serum 25-OH-D3 concentration, a higher concentration of intact parathormone and more a frequent occurrence of joint pain were found in HH patients compared with the control group. In HH patients, the diagnosis of liver cirrhosis was associated with lower serum 25-OH-D3 and osteocalcin concentrations. In HH, DXA with the TBS option is a valuable tool in the early assessment of the bone microarchitecture and fracture risk. A supplementation of vitamin D, monitoring its concentration, should be considered especially in HH patients with liver damage and liver cirrhosis.

A Case Study of Hemochromatosis and Conflicting Point Shear Wave Measurements in the Assessment of Liver Fibrosis.

There are multiple factors that affect the shear wave speed in the assessment of liver stiffness. In this case report, we present a case of hemochromatosis that has elevated liver stiffness suggestive of significant fibrosis or cirrhosis; however on liver biopsy, no fibrosis was identified. This article will discuss the possibility that liver iron deposition may affect SWE measurements of the liver, leading to inaccurate assessment of liver fibrosis. In these cases, a liver biopsy may be required for accurate liver assessment.

Feasibility Study of NMR Based Serum Metabolomic Profiling to Animal Health Monitoring: A Case Study on Iron Storage Disease in Captive Sumatran Rhinoceros (Dicerorhinus sumatrensis).

A variety of wildlife species maintained in captivity are susceptible to iron storage disease (ISD), or hemochromatosis, a disease resulting from the deposition of excess iron into insoluble iron clusters in soft tissue. Sumatran rhinoceros (Dicerorhinus sumatrensis) is one of the rhinoceros species that has evolutionarily adapted to a low-iron diet and is susceptible to iron overload. Hemosiderosis is reported at necropsy in many African black and Sumatran rhinoceroses but only a small number of animals reportedly die from hemochromatosis. The underlying cause and reasons for differences in susceptibility to hemochromatosis within the taxon remains unclear. Although serum ferritin concentrations have been useful in monitoring the progression of ISD in many species, there is some question regarding their value in diagnosing hemochromatosis in the Sumatran rhino. To investigate the metabolic changes during the development of hemochromatosis and possibly increase our understanding of its progression and individual susceptibility differences, the serum metabolome from a Sumatran rhinoceros was investigated by nuclear magnetic resonance (NMR)-based metabolomics. The study involved samples from female rhinoceros at the Cincinnati Zoo (n = 3), including two animals that died from liver failure caused by ISD, and the Sungai Dusun Rhinoceros Conservation Centre in Peninsular Malaysia (n = 4). Principal component analysis was performed to visually and statistically compare the metabolic profiles of the healthy animals. The results indicated that significant differences were present between the animals at the zoo and the animals in the conservation center. A comparison of the 43 serum metabolomes of three zoo rhinoceros showed two distinct groupings, healthy (n = 30) and unhealthy (n = 13). A total of eighteen altered metabolites were identified in healthy versus unhealthy samples. Results strongly suggest that NMR-based metabolomics is a valuable tool for animal health monitoring and may provide insight into the progression of this and other insidious diseases.

Examining the clinical use of hemochromatosis genetic testing.

BACKGROUND: Hereditary hemochromatosis leads to an increased lifetime risk for end-organ damage due to excess iron deposition. Guidelines recommend that genetic testing be performed in patients with clinical suspicion of iron overload accompanied by elevated serum ferritin and transferrin saturation levels. OBJECTIVE: To evaluate guideline adherence and the clinical and economic impact of HFE genetic testing. METHODS: The electronic charts of patients submitted for HFE testing in 2012 were reviewed for genetic testing results, biochemical markers of iron overload and clinical history of phlebotomy. RESULTS: A total of 664 samples were sent for testing, with clinical, biochemical and phlebotomy data available for 160 patients. A positive C282Y homozygote or C282Y/H63D compound heterozygote test result was observed in 18% of patients. Patients with an at-risk HFE genotype had significantly higher iron saturation, serum iron and hemoglobin (P<0.001), without higher ferritin or liver enzyme levels. Fifty percent of patients referred for testing did not have biochemical evidence of iron overload (transferrin saturation >45% and ferritin level >300 µg/L). Patients were four times more likely to undergo phlebotomy if they were gene test positive (RR 4.29 [95% CI 2.35 to 7.83]; P<0.00001). DISCUSSION: One-half of patients referred for testing did not exhibit biochemical evidence of iron overload. Many patients with biochemical evidence of iron overload, but with negative genetic test results, did not undergo phlebotomy. A requisition to determine clinical indication for testing may reduce the use of the HFE genetic test. Finally, improvement of current genetic test characteristics would improve rationale for the test. CONCLUSION: A significant proportion of hemochromatosis genetic testing does not adhere to current guidelines and would not alter patient management.

Erythrocytapheresis compared with whole blood phlebotomy for the treatment of hereditary haemochromatosis.

BACKGROUND: Hereditary haemochromatosis may result in severe organ damage which can be prevented by therapy. We studied the possible advantages and disadvantages of erythrocytapheresis as compared with phlebotomy in patients with hereditary haemochromatosis. MATERIALS AND METHODS: In a prospective, randomised, open-label study, patients with hereditary haemochromatosis were randomised to bi-weekly apheresis or weekly whole blood phlebotomy. Primary end-points were decrease in ferritin levels and transferrin saturation. Secondary endpoints were decrease in haemoglobin levels, discomfort during the therapeutic procedure, costs and technicians' working time. RESULTS: Sixty-two patients were included. Thirty patients were randomised to apheresis and 32 to whole blood phlebotomy. Initially, ferritin levels declined more rapidly in the apheresis group, and the difference became statistically highly significant at 11 weeks; however, time to normalisation of ferritin level was equal in the two groups. We observed no significant differences in decline of transferrin saturation, haemoglobin levels or discomfort. The mean cumulative technician time consumption until the ferritin level reached 50 µg/L was longer in the apheresis group, but the difference was not statistically significant. The cumulative costs for materials until achievement of the desired ferritin levels were three-fold higher in the apheresis group. CONCLUSION: Treatment of hereditary haemochromatosis with erythrocytapheresis instead of whole blood phlebotomy results in a more rapid initial decline in ferritin levels and a reduced number of procedures per patient, but not in earlier achievement of target ferritin level. The frequency of discomfort was equally low with the two methods. The costs and, probably, technician time consumption were higher in the apheresis group.

Transferrin saturation and hospital length of stay and mortality in Medicare beneficiaries.

OBJECTIVES: To evaluate in a large, nationally representative cohort the association between high serum transferrin saturation (TS) and hospital length of stay and mortality in older adults. DESIGN: Prospective cohort. SETTING: Longitudinal analyses of the Third National Health and Nutrition Examination Survey linked to Medicare claims from 1991 through 2006. PARTICIPANTS: Medicare beneficiaries aged 65 and older at baseline. MEASUREMENTS: Transferrin saturation collected on each participant at baseline was characterized as <20.0%, 20.0% to 54.9%, and 55.0% and greater. Length of stay in the hospital and death in the hospital were primary outcomes. Analyses were adjusted for age, sex, race and ethnicity, education, and severity of illness. RESULTS: Individuals hospitalized during the study period (79.4%) with high (odds ratio (OR) = 2.54, 95% confidence interval (CI) = 1.05-6.12) or low (OR = 1.31, 95% CI = 1.07-1.62) TS had a significantly greater risk of death than those with moderate TS. Individuals with high TS had longer average length of stay per hospitalization (11.1 days, (standard error, SE 1.7 days), P = .01) than those with moderate TS (8.4 (0.3) days). Individuals with high TS also had more hospital days per year (8.6 (2.0) days, P = .04) than those with moderate TS (6.7 (0.5) days). CONCLUSION: High TS is associated with longer length of stay and death in the hospital (unweighted N = 3,847, weighted N = 28,395,464).

Erythrocytapheresis versus phlebotomy in the initial treatment of HFE hemochromatosis patients: results from a randomized trial.

BACKGROUND: Standard treatment of newly diagnosed HFE hemochromatosis patients is phlebotomy. Erythrocytapheresis provides a new therapeutic modality that can remove up to three times more red blood cells per single procedure and could thus have a clinical and economic benefit. STUDY DESIGN AND METHODS: To compare the number of treatment procedures between erythrocytapheresis and phlebotomy needed to reach the serum ferritin (SF) target level of 50 µg/L, a two-treatment-arms, randomized trial was conducted in which 38 newly diagnosed patients homozygous for C282Y were randomly assigned in a 1:1 ratio to undergo either erythrocytapheresis or phlebotomy. A 50% decrease in the number of treatment procedures for erythrocytapheresis compared to phlebotomy was chosen as the relevant difference to detect. RESULTS: Univariate analysis showed a significantly lower mean number of treatment procedures in the erythrocytapheresis group (9 vs. 27; ratio, 0.33; 95% confidence interval [CI], 0.25-0.45; Mann-Whitney p < 0.001). After adjustments for the two important influential factors initial SF level and body weight, the reduction ratio was still significant (0.43; 95% CI, 0.35-0.52; p < 0.001). Cost analysis showed no significant difference in treatment costs between both procedures. The costs resulting from productivity loss were significantly lower for the erythrocytapheresis group. CONCLUSION: Erythrocytapheresis is highly effective treatment to reduce iron overload and from a societal perspective might potentially also be a cost-saving therapy.

Erythrocytapheresis plus erythropoietin: an alternative therapy for selected patients with hemochromatosis and severe organ damage.

We report the efficacy, tolerability and cost of erythocytoapheresis plus recombinant human erythropoietin (rHuEPO) in three patients with severe hereditary hemochromatosis (HH). Results indicate that this regimen could be a valid therapeutic alternative in complicated HH patients. Its cost, however, limits its use to patients whose clinical conditions prevent a proper phlebotomy regimen.

Factors affecting the uptake of screening: a randomised controlled non-inferiority trial comparing a genotypic and a phenotypic strategy for screening for haemochromatosis.

BACKGROUND/AIMS: Haemochromatosis provides an example where a novel pragmatic genotypic screening strategy may be compared with a phenotypic strategy assessing factors affecting uptake, feasibility and cost. METHODS: A randomised controlled 'non-inferiority' trial testing the hypothesis that the uptake of testing in the genotypic strategy would not be inferior to the uptake in a phenotypic screening strategy. Three thousand individuals aged 30-70 were randomly selected and randomly allocated (stratified by age and sex) to one of two screening strategies. Phenotypic-transferrin saturation on blood sample taken at GP surgery or genotypic-saliva sample taken at home; followed in screen positive individuals with assessment of iron status and genotyping. RESULTS: The difference in uptake between the two strategies was 3.4% (95% CI=0.5-6.8). Uptake was low (32%) and least in young men from socially deprived areas. Phenotypic screening was least costly. CONCLUSIONS: In this study, investigating the uptake of screening for a treatable disease in primary care, the uptake of screening with the genotypic strategy was not inferior to that in the phenotypic strategy. The poor uptake in younger men would further limit the effectiveness of screening for haemochromatosis and may have implications for other screening programmes targeted to this group.

Total iron binding capacity and transferrin concentration in the assessment of iron status.

Transferrin concentration and total iron binding capacity (TIBC) are currently used to assess iron status. Although correlation between TIBC and transferrin is generally considered as good, conversion factors between the two analytes found in literature show large differences. Although the price per test is lower for TIBC, there are a number of analytical advantages of serum transferrin. Due to binding of iron to other plasma proteins (mainly albumin), TIBC methods generally overestimate the iron binding capacity of transferrin. Moreover, no generic reference values are available for TIBC. In contrast to TIBC, internationally accepted interim reference ranges are available for serum transferrin. The introduction of the international CRM 470 protein standard material has lead to a significant reduction in interlaboratory variation for transferring measurements. In view of these observations, determination of transferrin concentration, rather than TIBC, is recommended. However, in non-European populations characterized by a marked genetic variation in transferrin (TF BC and TF CD variants), in certain cases, immunochemical determination of transferrin may lead to errors. In these populations, TIBC measurements may be preferred.

Nonexpressing homozygotes for C282Y hemochromatosis: minority or majority of cases?

Genetic testing for the C282Y mutation of the HFE gene has been a major advance in the diagnosis of hereditary hemochromatosis. In most studies, more than 90% of typical hemochromatosis patients are homozygous for the C282Y mutation. Large-scale population screening studies in predominantly Caucasian populations have demonstrated a high prevalence of C282Y homozygotes of approximately 1 in 300. Despite this high prevalence by genetic testing, the clinical diagnosis of hemochromatosis and mortality from the disease are much less common. One possibility is the presence of many undiagnosed cases with nonspecific symptoms, and deaths occurring that are attributed to liver disease, diabetes, and heart disease without the recognition of iron overload secondary to hemochromatosis. Another possibility is a high prevalence of nonexpressing homozygotes. In this review, the available data on nonexpressing C282Y homozygotes is collected including information on pathogenesis, environmental interactions, and implications for population screening using genetic testing.

Screening for genetic haemochromatosis in blood samples with raised alanine aminotransferase.

BACKGROUND: In the UK approximately 1 in 140 people are homozygous for the C282Y mutation of the HFE gene and are at risk from iron overload caused by genetic haemochromatosis (GH). Early detection can prevent organ damage secondary to iron deposition and increase life expectancy. AIM: To screen for GH in all blood samples sent to the laboratory for routine liver function tests in which raised serum alanine aminotransferase (ALT) activity was detected. METHODS: ALT was measured in sera sent to the laboratory for routine liver function tests. In those samples found to have raised activity, transferrin saturation and ferritin were measured followed by genetic testing when transferrin saturation was increased. RESULTS: Of the 35 069 serum samples assayed for routine liver function tests, 1490 (4.2%) had raised ALT levels (>50 u/l). Transferrin saturation and serum ferritin concentrations were measured in these patient samples, and in 56 transferrin saturation was >60%. Further blood samples were requested from these patients for genetic testing: 33 samples were obtained. There were nine patients homozygous for the C282Y mutation of the HFE gene and three compound heterozygotes (heterozygous for both C282Y and H63D mutations). CONCLUSIONS: The association of raised ALT activity and transferrin saturation of >60% could provide a simple, cost effective method for detecting individuals with clinical haemochromatosis. Although many patients with GH may have been missed, this study suggests that the clinical penetrance of the disorder may be much lower than is generally supposed and that genetic screening will identify many people who may never develop clinical haemochromatosis.

Screening for hereditary hemochromatosis in siblings and children of affected patients. A cost-effectiveness analysis.

BACKGROUND: Screening for hereditary hemochromatosis is traditionally done by using serum iron studies. However, mutation analysis of the hemochromatosis-associated HFE gene has recently become available. OBJECTIVE: To compare the cost-effectiveness of no screening with four screening strategies that incorporate HFE gene testing or serum iron studies. DESIGN: Cost-effectiveness analysis. DATA SOURCES: Published literature. TARGET POPULATION: Siblings and children of an affected proband. TIME HORIZON: Lifetime from 10 years of age (children) or 45 years of age (siblings). PERSPECTIVE: Societal. INTERVENTION: 1) Serum iron studies. 2) Gene testing of the proband. If the proband is homozygous (C82Y+/+), the spouse undergoes gene testing; if he or she is heterozygous (C82Y+/-), the children undergo gene testing. 3) Gene testing of the proband; if he or she is homozygous, relatives undergo gene testing. 4) Direct gene testing of relatives. OUTCOME MEASURES: Cost per life-year saved and incremental cost-effectiveness ratio. RESULTS OF BASE-CASE ANALYSIS: In children, HFE gene testing of the proband was the most cost-effective strategy for screening one child (incremental cost-effectiveness ratio, $508 per life-year saved). HFE gene testing of the proband followed by testing of the spouse was the most cost-effective strategy for screening two or more children (incremental cost-effectiveness ratio, $3665 per life-year saved). In siblings, all screening strategies were dominant compared with no screening. Strategies using HFE gene testing were less costly than serum iron studies. RESULTS OF SENSITIVITY ANALYSIS: Despite varying the prevalence of mutations and regardless of the cost of the genetic test in one- and two-way sensitivity analyses, HFE gene testing remained cost-effective. CONCLUSIONS: HFE gene testing for the C282Y mutation is a cost-effective method of screening relatives of patients with hereditary hemochromatosis.

Population-based screening for hemochromatosis using phenotypic and DNA testing among employees of health maintenance organizations in Springfield, Missouri.

BACKGROUND: Hemochromatosis reportedly affects 3 to 8 persons per 1,000 and is associated with an elevated risk of morbidity and mortality. We sought to ascertain its prevalence in a community and to assess the association between phenotype and genotype. METHODS: All health maintenance organization employees were invited to participate in hemochromatosis screening using a repeated elevation of the transferrin saturation test as the case definition (> or = 50% in women and > or = 60% in men with no other cause). Iron overload from hemochromatosis was defined as serum ferritin concentration > or = 95th percentile and mobilizable iron > or = 99th percentile for age and sex, or hepatic iron index > or = 1.9. The HFE gene was analyzed for mutations. RESULTS: Participation among employees was 28% (1,653 of 6,000); 83% were women. The prevalence of hemochromatosis was 8 per 1,000 (13 of 1,653), and the prevalence of iron overload from hemochromatosis was 4 per 1,000 (5 of 1,653). Compared with those who had no HFE mutation, the relative risk (RR) for hemochromatosis was greatest for C282Y homozygotes (RR = 147), compound heterozygotes (RR = 19), and H63D homozygotes (RR = 9). Overall, 38% of participants had at least one HFE mutation. Screening based on an initial elevated transferrin saturation test had the best sensitivity, whereas DNA testing offered the best specificity and predictive value positive for iron overload disease. CONCLUSIONS: In this population, we found a greater than expected prevalence of hemochromatosis and demonstrated a clear association with the HFE genotype. Promotion of screening is complicated by controversies in case definition and the large number of persons who will be detected before they have clinically significant iron loading, in whom the risk of clinical disease is unknown. Larger screening studies in more diverse populations are necessary to characterize the burden of disease and to follow those at risk (based on HFE or iron status measures) to establish the natural history of hemochromatosis.

A survey of phlebotomy among persons with hemochromatosis.

BACKGROUND: One in 10 whites in the United States is a carrier for hemochromatosis and an estimated 1 in 200 is clinically affected. Early treatment with therapeutic phlebotomy to remove excess iron can prevent associated chronic diseases. However, little information is available on the amount of blood withdrawn or the rates of withdrawal from hemochromatosis patients. The patterns of therapeutic phlebotomy and the magnitude of charges in persons with hemochromatosis were surveyed. STUDY DESIGN AND METHODS: Surveys were mailed to persons with hemochromatosis identified by health care providers, blood centers, patient advocacy groups, and the Internet. There were 2362 respondents to the survey from the United States. RESULTS: Thirty-seven percent of respondents reported being voluntary blood donors prior to diagnosis. The mean rate of therapeutic phlebotomy for iron depletion was 2.6 units per month (mean duration, 13 months). The mean rate of maintenance phlebotomy was 0.5 units per month. Therapeutic phlebotomy rates varied by sex, age, reason for diagnosis, and severity of symptoms. Seventy-six percent of respondents reported full or partial insurance coverage of therapeutic phlebotomy charges. Seventy-six percent received therapeutic phlebotomy services in a hospital or physician's office and 30 percent in a blood center. Charges for therapeutic phlebotomy varied by site, with a mean cost of $90 in hospitals and $52 in blood centers. Fifty-four percent of respondents attempted to donate blood after their diagnosis but were excluded. CONCLUSION: The amount of blood withdrawn from persons with hemochromatosis is substantial. The location where patients received phlebotomy services appears to be influenced by charges and time since diagnosis.

Screening for hemochromatosis. A public health perspective.

CONTEXT: The discovery of the HFE gene in 1996 has introduced DNA testing as a possible tool for screening and diagnosis of hemochromatosis and increased interest in the disorder. Population screening using transferrin saturation has been advocated by experts to permit early detection and treatment with phlebotomy before the onset of clinical disease. METHODS: Based on a literature review, we consider the relative risks and merits of two screening tests as part of a broader look at the evidence required for the recommendation of universal screening for hemochromatosis. RESULTS: Several questions must be answered before universal screening can be recommended. Uncertainties remain about the penetrance and preventable disease burden, laboratory standardization, and optimal strategies to minimize potential risks of screening for hemochromatosis. CONCLUSIONS: As a common genetic disorder with simple, effective therapy, hemochromatosis offers a model for other genetically influenced chronic diseases that some day may have interventions to improve prognosis. Resolution of questions related to prevention of chronic diseases from hemochromatosis, therefore, will have broad usefulness in the future.

The effect of transferrin polymorphisms on iron metabolism.

The effect of five different transferrin variants (TFv1, TFv2, TFv3, TFv4, and TFv5) on the hemoglobin level, mean corpuscular volume (MCV), ferritin level, percent transferrin saturation (%TS), and the unsaturated iron binding capacity (UIBC) was investigated in subjects with defined HFE haplotypes, 919 persons undergoing health screening and 113 patients with clinical hemochromatosis. The most common variant is TFv4; the population distribution of this variant was also studied. None of the variants were found to have an effect on any of the parameters of iron metabolism that were investigated. Moreover, the frequency of these variants in patients with clinically significant hemochromatosis was no different from that in the general population. We conclude that these polymorphisms in transferrin do not play a role in the expression of hemochromatosis, nor do they produce any other significant changes in iron metabolism.

The laboratory assessment of iron status--an update.

The description by Ramsay in 1957 of a practical way of determining the total iron binding capacity of serum (a measure of transferrin concentration) provided a diagnostic test for both iron deficiency and iron overload. Since 1957 the introduction of the assay for serum ferritin (in 1972) has made it possible to assess the levels of storage iron in normal subjects and assays for free erythrocyte protoporphyrin and the circulating transferrin receptor methods to evaluate iron supply for erythropoiesis. In 1957 iron metabolism in man was already well understood but its evaluation relied on measurement of tissue iron concentrations and the use of radioisotopes of iron to measure rates of erythropoiesis. The evaluation can now be carried out using the various blood assays along with the measurement of haemoglobin concentration but interpretation of the measurements in disease still requires an understanding of the way in which these measures are influenced by pathological processes.

Iron disorders can mimic anything, so always test for them.

Routinely measuring iron status is necessary because not only are about 6% of Americans in significant negative iron balance, but about 1% have iron overload. Serum ferritin is in equilibrium with body iron stores, and is the only blood test that measures them. Barring inflammation, each one ng (0.0179 pmol) ferritin/ml of serum indicates approximately 10 mg (0.179 mmol) of body iron stores. Very early Stage I positive balance is best recognized by measuring saturation of iron binding capacity. Conversely, serum ferritin best recognizes early (Stage I and II) negative balance. Deviations from normal are: 1. Both stages of iron depletion (i.e. low stores, no dysfunction). Negative iron balance Stage I is reduced iron absorption producing moderately depleted iron stores. Stage II is severely depleted stores, without dysfunction. These stages include over half of all cases of negative iron balance. Treated with iron, they never progress to dysfunction, i.e. to disease. 2. Both stages of iron deficiency. Deficiency is inadequate iron for normal function, i.e. dysfunction, disease. Negative balance Stage III is dysfunction without anemia; Stage IV is with anemia. 3. Positive iron balance: Stage I is a multi-year period without dysfunction. Supplements of iron and/or vitamin C promote progression to dysfunction (disease). Iron removal prevents progression. Stage II is iron overload disease, encompassing years of insidiously progressive damage to tissues and organs from iron overload. Iron removal arrests progression.