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1.
Retina ; 37(12): 2238-2247, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28079755

RESUMO

PURPOSE: To analyze macular pigment (MP) amount and distribution in patients with macular telangiectasia Type 2 receiving oral zeaxanthin supplementation in a randomized, open-label, interventional trial. METHODS: Eight macular telangiectasia Type 2 patients were randomized to 10 mg or 20 mg of zeaxanthin per day. At each visit, best-corrected visual acuity, contrast sensitivity, fundus biomicroscopy, color fundus photography, autofluorescence imaging, optical coherence tomography, and serum carotenoid levels were tested. Patients were assessed at baseline and after 6, 12, 18, and 24 months of zeaxanthin supplementation. Concentration of MP was analyzed and calculated from autofluorescence imaging obtained at 488-nm excitation wavelength. Serum carotenoid levels were obtained using high-performance liquid chromatography. RESULTS: The majority of patients had definite increases in the intensity of hypofluorescent ring of MP, but none of them deposited MP centrally at the fovea. Although some patients noted subjective improvements in vision, no objective improvements could be documented, and there were no changes in foveal optical coherence tomographic features. Yellowish, hypofluorescent crystals appeared in one patient's macular region with no change in visual acuity. These inner retinal crystals disappeared several months after discontinuing her 20-mg zeaxanthin supplement. CONCLUSION: Based on the current study, zeaxanthin supplementation does not result in any visual benefit in patients with macular telangiectasia Type 2 and does not reestablish a normal peaked distribution of MP in the fovea. One patient developed a novel, reversible, crystalline maculopathy in response to zeaxanthin supplementation that was reminiscent of canthaxanthin crystalline maculopathy.


Assuntos
Suplementos Nutricionais , Macula Lutea/patologia , Pigmento Macular/metabolismo , Telangiectasia Retiniana/dietoterapia , Telangiectasia Hemorrágica Hereditária/dietoterapia , Zeaxantinas/administração & dosagem , Administração Oral , Adulto , Idoso , Carotenoides/sangue , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Macula Lutea/efeitos dos fármacos , Macula Lutea/metabolismo , Masculino , Pessoa de Meia-Idade , Imagem Óptica/métodos , Telangiectasia Retiniana/diagnóstico , Telangiectasia Retiniana/metabolismo , Telangiectasia Hemorrágica Hereditária/diagnóstico , Telangiectasia Hemorrágica Hereditária/metabolismo , Fatores de Tempo , Resultado do Tratamento , Acuidade Visual , Zeaxantinas/farmacocinética
2.
PLoS One ; 8(10): e76516, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24146883

RESUMO

BACKGROUND: Iron deficiency anemia remains a major global health problem. Higher iron demands provide the potential for a targeted preventative approach before anemia develops. The primary study objective was to develop and validate a metric that stratifies recommended dietary iron intake to compensate for patient-specific non-menstrual hemorrhagic losses. The secondary objective was to examine whether iron deficiency can be attributed to under-replacement of epistaxis (nosebleed) hemorrhagic iron losses in hereditary hemorrhagic telangiectasia (HHT). METHODOLOGY/PRINCIPAL FINDINGS: The hemorrhage adjusted iron requirement (HAIR) sums the recommended dietary allowance, and iron required to replace additional quantified hemorrhagic losses, based on the pre-menopausal increment to compensate for menstrual losses (formula provided). In a study population of 50 HHT patients completing concurrent dietary and nosebleed questionnaires, 43/50 (86%) met their recommended dietary allowance, but only 10/50 (20%) met their HAIR. Higher HAIR was a powerful predictor of lower hemoglobin (p = 0.009), lower mean corpuscular hemoglobin content (p<0.001), lower log-transformed serum iron (p = 0.009), and higher log-transformed red cell distribution width (p<0.001). There was no evidence of generalised abnormalities in iron handling Ferritin and ferritin(2) explained 60% of the hepcidin variance (p<0.001), and the mean hepcidinferritin ratio was similar to reported controls. Iron supplement use increased the proportion of individuals meeting their HAIR, and blunted associations between HAIR and hematinic indices. Once adjusted for supplement use however, reciprocal relationships between HAIR and hemoglobin/serum iron persisted. Of 568 individuals using iron tablets, most reported problems completing the course. For patients with hereditary hemorrhagic telangiectasia, persistent anemia was reported three-times more frequently if iron tablets caused diarrhea or needed to be stopped. CONCLUSIONS/SIGNIFICANCE: HAIR values, providing an indication of individuals' iron requirements, may be a useful tool in prevention, assessment and management of iron deficiency. Iron deficiency in HHT can be explained by under-replacement of nosebleed hemorrhagic iron losses.


Assuntos
Hematínicos/uso terapêutico , Hepcidinas/metabolismo , Deficiências de Ferro , Modelos Biológicos , Telangiectasia Hemorrágica Hereditária/metabolismo , Adulto , Idoso , Dieta , Suplementos Nutricionais , Epistaxe/epidemiologia , Feminino , Humanos , Ferro da Dieta/farmacologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recomendações Nutricionais , Análise de Regressão , Adulto Jovem
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