Thyroid diseases in sub-Saharan Africa
ABSTRACT Thyroid gland diseases vary according to the environment. In sub-Saharan Africa, they are also influenced by population isolation and the absence of food self-sufficiency, both factors affecting the onset and persistence of iodine-deficiency goiters. More cosmopolitan diseases are now added to these thyroid disorders. Women are mainly affected (94.2%), most often with euthyroid goiters (54.7%), followed by Graves disease (13.1%), hypothyroidism (8.8%), thyroiditis (6.6%), toxic multinodular goiters (6.6 %) and unclassified goiters (10%) [Gabon]. The paucity of laboratories specializing in endocrinology and of nuclear medicine facilities, the delay in diagnosis that results in compressive or recurrent goiters, and endemic goiters are all typical in Africa. In children and adolescents, death rates increase with congenital or acquired thyroiditis as with delayed physical or mental development. In this environment, thyroiditis can also be pregnancy-related. Very recent surveys show a prevalence of endemic goiters of 28.6% in the community of Sekota, Ethiopia, 64-70% in Sahel-Sudan (population aged 10-20 years), 20-29% in KwaZulu-Natal (school children), 14.3-30.2% in Namibia (school children), 0.21% (congenital hypothyroidism or cretinism) in Plateau State, Nigeria, 55.2% at Zitenga, Burkina Faso (210 persons 0-45 years), and 10% in Hararé and Wedza, Zimbabwe (newborn TSH >10.1 microIU/mL). The prevalence of goiters is 43.6% in children emigrating from Ethiopia to Israel. Millet from semi-arid zones contains apigenin at a concentration of 150 mg/kg and luteolin at 350 mg/kg, both of which can interfere with thyroid function. The harmful effects of cassava (also known as manioc) are better known: milling cassava reduces its goitrogenic potential. In addition to iodine deficiency, selenium deficiency, and the effect of the thiocyanates in cassava, ion concentrations in soil and drinking water appear to play a role. The proportion of thyroid surgery indicated for hyperthyroidism has tripled, now accounting for 18.5% of all such operations. This disorder is found today in subjects older than 50 years, mainly from rural areas, and caused most often by Graves disease (25 of 51 cases). Graves disease in young women can cause serious problems during pregnancy; in such cases assessment of the minimal effective dose of antithyroid agents is essential. Carbimazole leads to remission in 61% of cases of Graves disease. Hypothyroidism can be auto-immune and often in patent forms because of insufficient screening in Africa: 24 cases in Dakar (1984) and 37 others noticed by us (1998). Single-nodule tumors were assessed in 89 patients in Khartoum: they were found to be simple goiters in 72% of cases, follicular adenoma in 13.5%, cancer in 13.5% (with 6 of the 12 cases follicular, 5 papillary, and 1 anaplastic). The sex ratio for thyroid cancer in Ouagadougou is 0.22, thus mainly women. It affects mainly women in their 30s. Thyroid cancer at Ibadan was found to be papillary carcinoma in 45.3% of cases; follicular forms were seen in 44.5% and this series includes 5% of medullary cancers (7 cases), with a mean age of 34 years. Already 4 other cases from Francophone sub-Saharan Africa have been noticed. Iodine deficiency is suggested to play a role because follicular cancer in southern Africa accounts for up to 55% of thyroid cancers. Thyroid cancers in Algeria are associated with low socioeconomic status and characterized by a high prevalence of cancers discovered at an advanced stage and of anaplastic carcinomas. Oral potassium iodate is recommended: 30 mg of iodate a month or 8 mg every two weeks. Iodized oil has been recommended by some authors, as well as a combination of iodine and sugar, and the iodation of drinking water; these are in addition to the proposed methods of opening up areas by new infrastructure). In conclusion, thyroid disease is due predominantly to iodine deficiency and goitrogenic products, but we also note the increasing emergence of hyperthyroidism, especially Graves disease, atrophic auto-immune hypothyroidism, and thyroid cancer. The insufficiency of infrastructure in transportation, endocrinology, and nuclear medicine are a public health challenge for the third millennium.
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ABSTRACT: Endemic goiter caused by iodine deficiency is still very common in sub-Saharan Africa and is a surgical challenge because of the often large size of the goiters. A retrospective analysis was made of patients who underwent operation for thyroid diseases during a surgical help program in Leo/Burkina Faso during a 7-year period from 2001 to 2008. A total of 253 cases presented with goiters grade III (WHO classification) were operated on: 134 hemithyroidectomies, 108 hemithyroidectomies combined with subtotal contralateral resection, and 11 total thyroidectomies were performed. The recurrent laryngeal injury rate was 0.8%, and the re-exploration rate for bleeding was 1.2%. Median hospital stay was 3.1 days. Histological examinations showed Graves' disease in 6 cases, and multinodular goiter in 231 cases. Follicular cancer was found in 15 cases, and anaplastic carcinoma was found in 1 case. Thyroid surgery can be performed with low complication rates under basic surgical conditions. Because of the size and pathology of the goiters, total thyroidectomy is the method of choice. However, considering the risk of the development of hypothyroidism due to poor understanding or difficult access to medication, a limited resection, e.g., hemithyroidectomy, is the most optimal operative strategy.World Journal of Surgery 11/2008; 32(12):2627-30. DOI:10.1007/s00268-008-9775-6 · 2.35 Impact Factor
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ABSTRACT: The impact of aqueous leaf extract of Hybanthus enneaspermus (HEaq) on pregnancy factors and litter survival was investigated in Sprague Dawley (SD) rat. Control group received distilled water while the test group received 2g/kg body weight of HEaq orally. Blood samples were collected on days one and twenty of pregnancy for total blood count, serum thyroid hormone, thyroid stimulating hormone (TSH) and thyrotropin releasing hormone (TRH) assay. Half the number of rats in each group was sacrificed on day nineteen of pregnancy and the placenta and foetus were removed and weighed. The second half carried their pregnancy to term. Number and weights of litter were recorded at birth and the litter were also subjected to righting reflex test. Post-natal survival rate was determined for each group while effect of HEaq was also examined in-vivo on the activities of pregnant myometrial muscle. HEaq significantly decreased (p<0.05) foetal weight, placenta weight, foetal growth and survival, number and weights of litter at birth, maternal serum triiodotyroxine T3 and TSH level. Mean corpuscular haemoglobin, white blood cell count, platelet count and lipid profile were significantly increased (P<0.05). HEaq increased the frequency and percentage contraction of gravid myometrial muscle in a dose dependent manner. Maternal consumption of aqueous leaf extract of Hybanthus enneaspermus adversely affected pregnancy and development of the foetus, as it precipitated resorption of developing foetus and reduced size and weight of litter at term.African Journal of Traditional, Complementary and Alternative Medicines 01/2012; 10(2):283-91. · 0.56 Impact Factor
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ABSTRACT: INTRODUCTION: The association hyperthyroidism-exophtalmia is pathognomonic of the Graves disease. Classically, the treatment is based on a pluridisciplinary step-by-step approach with a precise chronology. In some African places, these optimal conditions are not present. When confronted to such particular situations, it can be proposed to treat surgically at the same time the endocrine disease and the ophthalmologic complications. OBSERVATION: The authors report the case of a 42-year-old women suffering of a great thyreotoxic goiter with severe bilateral exophtalmia, treated by thyroidectomy and orbital decompression in the same session with a good result after 18 months. DISCUSSION: This non-conventional approach can be useful in particular situations when the medical environment is not optimal. It permits the radical treatment of their disease and improves the prognosis of patients with poor capacities for survey.Revue de stomatologie et de chirurgie maxillo-faciale 11/2012; 113(5). DOI:10.1016/j.stomax.2012.04.002 · 0.35 Impact Factor