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Linström M, Musekwa E, Nell EM, de Waard L, Chapanduka Z. The influence of hematological profiles on the transfusion management and mortality risk of mothers presenting to the obstetric unit of a South African tertiary medical facility. Transfusion 2024. [PMID: 38661229 DOI: 10.1111/trf.17849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 01/09/2024] [Accepted: 04/10/2024] [Indexed: 04/26/2024]
Abstract
BACKGROUND Laboratory results are frequently abnormal in pregnant mothers. Abnormalities usually relate to pregnancy or associated complications. Hematological abnormalities and age in pregnancy may increase the likelihood for transfusion and mortality. STUDY DESIGN AND METHODS Hematological profiles and transfusion history of pregnant mothers presenting to a tertiary hospital, were evaluated over 2 years. Age, anemia, leukocytosis and thrombocytopenia were assessed for transfusion likelihood. Iron deficiency and coagulation were assessed in transfused patients. Anemia, leukocytosis, thrombocytopenia, human immunodeficiency virus (HIV) and transfusion were assessed for mortality likelihood. RESULTS There were 12,889 pregnant mothers included. Mothers <19-years-old had the highest prevalence of anemia (31.5%) and proportion of transfusions (19%). The transfusion likelihood was increased in mothers with anemia (odds ratios [OR] = 6.41; confidence intervals at 95% [95% CI] 5.46-7.71), leukocytosis (OR = 2.35; 95% CI 2.00-2.76) or thrombocytopenia (OR = 2.71; 95% CI 2.21-3.33). Mothers with prolonged prothrombin times received twice as many blood products as their normal counterparts (p = .03) and those with iron deficiency anemia five times more blood products (p < .001). Increased likelihood for mortality was seen in patients with anemia (OR = 4.15, 95% CI 2.03-8.49), leukocytosis (OR = 2.68; 95% CI 1.19-6.04) and those receiving blood transfusion (OR = 3.6, 95% CI 1.75-7.47). DISCUSSION Adolescence, anemia, leukocytosis and thrombocytopenia expose mothers to a high risk for transfusion and/or mortality. These risk factors should promptly trigger management and referral of patients. Presenting hematological profiles are strong predictors of maternal outcome and transfusion risk.
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Affiliation(s)
- Michael Linström
- Division of Hematological Pathology, Department of Pathology, Stellenbosch University, Cape Town, South Africa
- Division of Hematopathology, National Health Laboratory Services, Tygerberg Hospital, Cape Town, South Africa
| | - Ernest Musekwa
- Division of Hematological Pathology, Department of Pathology, Stellenbosch University, Cape Town, South Africa
- Division of Hematopathology, National Health Laboratory Services, Tygerberg Hospital, Cape Town, South Africa
| | - Erica-Mari Nell
- Division of Hematological Pathology, Department of Pathology, Stellenbosch University, Cape Town, South Africa
- Division of Hematopathology, National Health Laboratory Services, Tygerberg Hospital, Cape Town, South Africa
| | - Liesl de Waard
- Department of Obstetrics and Gynecology, Stellenbosch University, Cape Town, South Africa
| | - Zivanai Chapanduka
- Division of Hematological Pathology, Department of Pathology, Stellenbosch University, Cape Town, South Africa
- Division of Hematopathology, National Health Laboratory Services, Tygerberg Hospital, Cape Town, South Africa
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Gantana E, Mashigo N, Abdullah I, Musekwa E, Lohlun R, Nell EM, Chetty C, Ntobongwana M, Chapanduka Z. Evaluation of an innovative new method for quantitation of plasma cells on CD138 immunohistochemistry. J Clin Pathol 2023; 76:261-265. [PMID: 34625512 DOI: 10.1136/jclinpath-2021-207828] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Accepted: 09/22/2021] [Indexed: 11/03/2022]
Abstract
AIM To compare the frequently used CD138 immunohistochemistry-based method of plasma cell quantitation, to a proposed new method, using interobserver and intraobserver concordance parameters. METHODS Archival CD138 immunohistochemically stained slides made from paraffin-embedded bone marrow biopsies of 33 patients with a confirmed diagnosis of multiple myeloma were used. Light microscopic examination was performed using low magnification lenses (10×) for both the overview estimation method (method A) and the new method (method B), and high magnification lenses (50×), for method B only. For method B, reviewers selected three areas with low, intermediate and high plasma cell densities using 10× lenses. Using a well-defined technique, the 50× lens was then used to count plasma cells as a percentage of all nucleated cells. After blinded relabelling of all the slides, the nine reviewers repeated the plasma cell quantitation using both methods. The plasma cell counts were obtained, and the review times were recorded. RESULTS Overall intraobserver concordance was comparable for method A (concordance correlation coefficient (CCC)=0.840) and method B (CCC=0.733). Interobserver concordance for method A (intraclass correlation coefficient (ICC)=0.793 and 0.713) and method B (ICC=0.657 and 0.658) indicated high similarity between reviewers. Method A showed poor interobserver concordance (ICC=0.105) at low plasma cell densities. CONCLUSIONS The new method is comparable to the frequently used overview estimation method in terms of intraobserver and interobserver concordance, and cost. The new method has superior interobserver concordance at low plasma cell densities. The new method appears more amenable to digital scanning and analysis.
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Affiliation(s)
- Ethan Gantana
- Department of Haematology, National Health Laboratory Service, Tygerberg Hospital and Stellenbosch University, Faculty of Medicine and Health Sciences, Cape Town, South Africa
| | - Nomusa Mashigo
- Department of Haematology, National Health Laboratory Service, Tygerberg Hospital and Stellenbosch University, Faculty of Medicine and Health Sciences, Cape Town, South Africa
| | - Ibtisam Abdullah
- Department of Haematology, National Health Laboratory Service, Tygerberg Hospital and Stellenbosch University, Faculty of Medicine and Health Sciences, Cape Town, South Africa
| | - Ernest Musekwa
- Department of Haematology, National Health Laboratory Service, Tygerberg Hospital and Stellenbosch University, Faculty of Medicine and Health Sciences, Cape Town, South Africa
| | - Robert Lohlun
- Department of Haematology, National Health Laboratory Service, Tygerberg Hospital and Stellenbosch University, Faculty of Medicine and Health Sciences, Cape Town, South Africa
| | - Erica-Mari Nell
- Department of Haematology, National Health Laboratory Service, Tygerberg Hospital and Stellenbosch University, Faculty of Medicine and Health Sciences, Cape Town, South Africa
| | - Carissa Chetty
- Department of Haematology, National Health Laboratory Service, Tygerberg Hospital and Stellenbosch University, Faculty of Medicine and Health Sciences, Cape Town, South Africa
| | - Monalisa Ntobongwana
- Department of Haematology, National Health Laboratory Service, Tygerberg Hospital and Stellenbosch University, Faculty of Medicine and Health Sciences, Cape Town, South Africa
| | - Zivanai Chapanduka
- Department of Haematology, National Health Laboratory Service, Tygerberg Hospital and Stellenbosch University, Faculty of Medicine and Health Sciences, Cape Town, South Africa
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Hussey H, Vreede H, Davies MA, Heekes A, Kalk E, Hardie D, van Zyl G, Naidoo M, Morden E, Bam JL, Zinyakatira N, Centner CM, Maritz J, Opie J, Chapanduka Z, Mahomed H, Smith M, Cois A, Pienaar D, Redd AD, Preiser W, Wilkinson R, Chetty K, Boulle A, Hsiao NY. Epidemiology and outcomes of SARS-CoV-2 infection associated with anti-nucleocapsid seropositivity in Cape Town, South Africa. medRxiv 2022:2022.12.01.22282927. [PMID: 36523408 PMCID: PMC9753787 DOI: 10.1101/2022.12.01.22282927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Background In low- and middle-income countries where SARS-CoV-2 testing is limited, seroprevalence studies can characterise the scale and determinants of the pandemic, as well as elucidate protection conferred by prior exposure. Methods We conducted repeated cross-sectional serosurveys (July 2020 - November 2021) using residual plasma from routine convenient blood samples from patients with non-COVID-19 conditions from Cape Town, South Africa. SARS-CoV-2 anti-nucleocapsid antibodies and linked clinical information were used to investigate: (1) seroprevalence over time and risk factors associated with seropositivity, (2) ecological comparison of seroprevalence between subdistricts, (3) case ascertainment rates, and (4) the relative protection against COVID-19 associated with seropositivity and vaccination statuses, to estimate variant disease severity. Findings Among the subset sampled, seroprevalence of SARS-CoV-2 in Cape Town increased from 39.2% in July 2020 to 67.8% in November 2021. Poorer communities had both higher seroprevalence and COVID-19 mortality. Only 10% of seropositive individuals had a recorded positive SARS-CoV-2 test. Antibody positivity before the start of the Omicron BA.1 wave (28 November 2021) was strongly protective for severe disease (adjusted odds ratio [aOR] 0.15; 95%CI 0.05-0.46), with additional benefit in those who were also vaccinated (aOR 0.07, 95%CI 0.01-0.35). Interpretation The high population seroprevalence in Cape Town was attained at the cost of substantial COVID-19 mortality. At the individual level, seropositivity was highly protective against subsequent infections and severe COVID-19. Funding Wellcome Trust, National Health Laboratory Service, the Division of Intramural Research, NIAID, NIH (ADR) and Western Cape Government Health.
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Affiliation(s)
- Hannah Hussey
- Health Intelligence, Western Cape Government: Health, South Africa
- Metro Health Services, Western Cape Government: Health
- School of Public Health, University of Cape Town, South Africa
| | - Helena Vreede
- Division of Chemical Pathology, University of Cape Town, South Africa
- National Health Laboratory Service, South Africa
| | - Mary-Ann Davies
- Health Intelligence, Western Cape Government: Health, South Africa
- School of Public Health, University of Cape Town, South Africa
- Centre for Infectious Disease Epidemiology and Research, School of Public Health, University of Cape Town, South Africa
| | - Alexa Heekes
- Health Intelligence, Western Cape Government: Health, South Africa
- Centre for Infectious Disease Epidemiology and Research, School of Public Health, University of Cape Town, South Africa
| | - Emma Kalk
- School of Public Health, University of Cape Town, South Africa
- Centre for Infectious Disease Epidemiology and Research, School of Public Health, University of Cape Town, South Africa
| | - Diana Hardie
- National Health Laboratory Service, South Africa
- Division of Medical Virology, University of Cape Town, South Africa
| | - Gert van Zyl
- National Health Laboratory Service, South Africa
- Division of Medical Virology, Stellenbosch University, South Africa
| | - Michelle Naidoo
- National Health Laboratory Service, South Africa
- Division of Medical Virology, University of Cape Town, South Africa
- Division of Medical Virology, Stellenbosch University, South Africa
| | - Erna Morden
- Health Intelligence, Western Cape Government: Health, South Africa
- School of Public Health, University of Cape Town, South Africa
| | - Jamy-Lee Bam
- Health Intelligence, Western Cape Government: Health, South Africa
| | - Nesbert Zinyakatira
- Health Intelligence, Western Cape Government: Health, South Africa
- School of Public Health, University of Cape Town, South Africa
| | | | - Jean Maritz
- Division of Medical Virology, Stellenbosch University, South Africa
- PathCare Reference Laboratory, Cape Town, South Africa
| | - Jessica Opie
- National Health Laboratory Service, South Africa
- Division of Haematology, University of Cape Town, South Africa
| | - Zivanai Chapanduka
- National Health Laboratory Service, South Africa
- Division of Haematology, Stellenbosch University, South Africa
| | - Hassan Mahomed
- Metro Health Services, Western Cape Government: Health
- Division of Health Systems and Public Health, Department of Global Health, Faculty of Medicine and Health Sciences, Stellenbosch University
| | - Mariette Smith
- Health Intelligence, Western Cape Government: Health, South Africa
- Centre for Infectious Disease Epidemiology and Research, School of Public Health, University of Cape Town, South Africa
| | - Annibale Cois
- School of Public Health, University of Cape Town, South Africa
- Division of Health Systems and Public Health, Department of Global Health, Faculty of Medicine and Health Sciences, Stellenbosch University
| | - David Pienaar
- Rural Health Services, Western Cape Government: Health
| | - Andrew D Redd
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Wolfgang Preiser
- National Health Laboratory Service, South Africa
- Division of Medical Virology, Stellenbosch University, South Africa
| | - Robert Wilkinson
- Wellcome Centre for Infectious Disease Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa
- The Francis Crick Institute, Midland Road, London, NW1 1AT, UK
- Department of Infectious Diseases, Imperial College London, W12 0NN, UK
| | - Kamy Chetty
- National Health Laboratory Service, South Africa
| | - Andrew Boulle
- Health Intelligence, Western Cape Government: Health, South Africa
- School of Public Health, University of Cape Town, South Africa
- Centre for Infectious Disease Epidemiology and Research, School of Public Health, University of Cape Town, South Africa
| | - Nei-Yuan Hsiao
- National Health Laboratory Service, South Africa
- Division of Medical Virology, University of Cape Town, South Africa
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Louw S, Jacobson BF, Wiggill TM, Chapanduka Z, Sarah Mayne E. HIV-associated thrombotic thrombocytopenic purpura (HIV-TTP): A practical guide and review of the literature. HIV Med 2022; 23:1033-1040. [PMID: 35373442 PMCID: PMC9790193 DOI: 10.1111/hiv.13305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 03/03/2022] [Accepted: 03/13/2022] [Indexed: 12/30/2022]
Abstract
BACKGROUND Thrombotic thrombocytopenic purpura (TTP), a serious thrombotic microangiopathy (TMA), is prevalent in the South African HIV-infected population. The exact pathogenesis of HIV-associated TTP (HIV-TTP) is however still unclear with diagnostic and therapeutic inconsistancies. METHODS A systematic review of the published literature regarding HIV-TTP was performed. RESULTS HIV-TTP is still associated with significant morbidity and mortality in Africa despite the availability of anti-retroviral therpy (ART). Diagnosis of HIV-TTP requires the presence of a micro-angiopathic haemolytic anaemia with significant red blood cell schistocytes and thrombocytopenia in the absence of another TMA but background activation of the coagulation system and inflammation in HIV infected people can result in diagnostic anbiguity. Plasma therapy in the form of infusion or exchange is successful but expensive, associated with side-effects and not widely available. Adjuvant immunosuppression therapy may of benefit in patients with HIV-TTP and ART must always be optimised. Endothelial dysfunction caused by chronic inflammation and complement activation most likely contributes to the development of HIV-TTP. CONCLUSION The role of adjuvant immunomodulating therpy, the therapeutic targets and pathogenic contribution from endothelial dysfunction in HIV-TTP requires further investigation.
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Affiliation(s)
- Susan Louw
- Department of Molecular Medicine and HaematologyFaculty of Health SciencesUniversity of Witwatersrand and National Health Laboratory ServiceJohannesburgSouth Africa
| | - Barry Frank Jacobson
- Department of Molecular Medicine and HaematologyFaculty of Health SciencesUniversity of Witwatersrand and National Health Laboratory ServiceJohannesburgSouth Africa
| | - Tracey Monica Wiggill
- Department of Molecular Medicine and HaematologyFaculty of Health SciencesUniversity of Witwatersrand and National Health Laboratory ServiceJohannesburgSouth Africa
| | - Zivanai Chapanduka
- Department of HaematologyUniversity of Stellenbosch and National Health Laboratory ServiceCape TownSouth Africa
| | - Elizabeth Sarah Mayne
- Department of ImmunologyFaculty of Health SciencesUniversity of Witwatersrand and National Health Laboratory ServiceJohannesburgSouth Africa
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Hinzmann R, Militz D, Zima T, Špaček M, Storm H, Chapanduka Z, Hauss O. Real-world data from Europe and Africa suggest that accuracy of systems for self-monitoring of blood glucose is frequently impaired by low hematocrit. Diabetes Res Clin Pract 2021; 177:108860. [PMID: 33989667 DOI: 10.1016/j.diabres.2021.108860] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 05/05/2021] [Accepted: 05/07/2021] [Indexed: 10/21/2022]
Abstract
AIMS Certain systems for self-monitoring of blood glucose (SMBG) demonstrate inaccuracy at low and high hematocrit (HCT). Manufacturers define HCT ranges for accurate performance. Our objective was to assess the frequency of HCT values that can lead to clinically relevant errors. METHODS In this cross-sectional study, we collected real-world data representing over 360,000 outpatients from the Netherlands (NL), the Czech Republic (CZ), and South Africa (ZA). These were subsequently stratified by sex and age and compared to commonly specified HCT range limits, reference intervals, and data from 1780 healthy Czech subjects. RESULTS HCT values were comparably distributed in NL and CZ. Outpatients had a higher dispersion of values than healthy subjects. Low HCT values in Europe were common in age groups with a high prevalence of diabetes. All ZA age groups showed a higher prevalence of low HCT than in Europe. CONCLUSIONS Real-world data indicate that SMBG systems specified to perform only within the frequently used 30-55% HCT range would leave 3% of outpatients in Europe and 18% in South Africa at risk of false SMBG results, with individual age strata being substantially higher. This could affect their diabetes management. Adequate SMBG systems should thus be chosen.
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Affiliation(s)
| | | | - Tomáš Zima
- 1st Faculty of Medicine Charles University and General University Hospital, Prague, Czech Republic
| | - Martin Špaček
- 1st Faculty of Medicine Charles University and General University Hospital, Prague, Czech Republic
| | - Huib Storm
- Certe Medical Diagnostics and Advice, Leeuwarden, the Netherlands
| | - Zivanai Chapanduka
- Faculty of Medicine and Health Sciences, Stellenbosch University and NHLS Tygerberg Hospital, Cape Town, South Africa
| | - Oliver Hauss
- Dr. Hauss Training & Consulting, Maxdorf, Germany
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Mutema L, Chapanduka Z, Musaigwa F, Mashigo N. In-depth investigation of turn-around time of full blood count tests requested from a clinical haematology outpatient department in Cape Town, South Africa. Afr J Lab Med 2021; 10:1318. [PMID: 34007817 PMCID: PMC8111617 DOI: 10.4102/ajlm.v10i1.1318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Accepted: 01/06/2021] [Indexed: 11/17/2022] Open
Abstract
Background The performance of laboratories can be objectively assessed using the overall turn-around time (TAT). However, TAT is defined differently by the laboratory and clinicians; therefore, it is important to determine the contribution of all the different components making up the laboratory test cycle. Objective We carried out a retrospective analysis of the TAT of full blood count tests requested from the haematology outpatient department at Tygerberg Academic Hospital in Cape Town, South Africa, with an aim to assess laboratory performance and to identify critical steps influencing TAT. Methods A retrospective audit was carried out, focused on the full blood count tests from the haematology outpatient department within a period of 3 months between 01 February and 30 April 2018. Data was extracted from the National Health Laboratory Service laboratory information system. The time intervals of all the phases of the test cycle were determined and total TAT and within-laboratory (intra-lab) TAT were calculated. Results A total of 1176 tests were analysed. The total TAT median was 275 (interquartile range [IQR] 200.0–1537.7) min with the most prolonged phase being from authorisation to review by clinicians (median 114 min; IQR: 37.0–1338.5 min). The median intra-lab TAT was 55 (IQR 40–81) min and 90% of the samples were processed in the laboratory within 134 min of registration. Conclusion Our findings showed that the intra-lab TAT was within the set internal benchmark of 3 h. Operational phases that were independent of the laboratory processes contributed the most to total TAT.
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Affiliation(s)
- Leonard Mutema
- Department of Haematological Pathology, Tygerberg Hospital, National Health Laboratory Service and Stellenbosch University, Cape Town, South Africa.,Department of Internal Medicine, University of KwaZulu-Natal, Durban, South Africa
| | - Zivanai Chapanduka
- Department of Haematological Pathology, Tygerberg Hospital, National Health Laboratory Service and Stellenbosch University, Cape Town, South Africa
| | - Fungai Musaigwa
- Department of Haematological Pathology, Tygerberg Hospital, National Health Laboratory Service and Stellenbosch University, Cape Town, South Africa
| | - Nomusa Mashigo
- Department of Haematological Pathology, Tygerberg Hospital, National Health Laboratory Service and Stellenbosch University, Cape Town, South Africa
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Gordeuk V, Mukiibi J, Hasstedt SJ, Samowitz W, Edwards CQ, West G, Ndambire S, Emmanual J, Nkanza N, Chapanduka Z. Iron overload in Africa. Interaction between a gene and dietary iron content. N Engl J Med 1992; 326:95-100. [PMID: 1727237 DOI: 10.1056/nejm199201093260204] [Citation(s) in RCA: 206] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND AND METHODS In contrast to hemochromatosis, which in white populations is inherited through a gene linked to the HLA locus, iron overload in sub-Saharan Africa is believed to result solely from increased dietary iron derived from traditional home-brewed beer. To examine the hypothesis that African iron overload also involves a genetic factor, we used likelihood analysis to test for an interaction between a gene (the hypothesized iron-loading locus) and an environmental factor (increased dietary iron) that determines transferrin saturation and unsaturated iron-binding capacity. We studied 236 members of 36 African families chosen because they contained index subjects with iron overload. Linkage to the HLA region was tested with use of lod scores. RESULTS In the index subjects, increased iron was present in both hepatocytes and cells of the mononuclear-phagocyte system. Among family members with increased dietary iron due to the consumption of traditional beer, transferrin saturation in serum was distributed bimodally, with 56 normal values (less than 60 percent saturation) and 44 elevated values; the mean serum ferritin concentration was five times higher in the subjects with elevated transferrin saturation (P less than 0.005). The pedigree analysis provided evidence of both a genetic effect (P less than 0.005) and an effect of increased dietary iron (P less than 0.005) on transferrin saturation and unsaturated iron-binding capacity. In the most likely model, increased dietary iron raised the mean transferrin saturation from 30 to 81 percent and lowered the mean unsaturated iron-binding capacity from 38 to 13 mumol per liter in subjects heterozygous for the iron-loading locus. The hypothesis of tight linkage to HLA was rejected. CONCLUSIONS Iron overload in Africa may be caused by an interaction between the amount of dietary iron and a gene distinct from any HLA-linked gene.
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Affiliation(s)
- V Gordeuk
- University of Zimbabwe School of Medicine, Harare
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