Prevalence of thyroid antibodies in Nigerian patients

Thyroid antibody testing is not routinely available in developing countries, and few studies have measured thyroid antibodies in Africans. The significance of thyroid autoimmunity in an African setting is thus unclear.

To determine the prevalence of thyroid antibodies in patients attending a Nigerian teaching hospital.

Prospective survey.

We measured antibodies to thyroglobulin (TgAb) and thyroid peroxidase (TPOAb) using an ELISA technique in 104 patients with various thyroid pathologies attending an endocrine referral centre in Lagos, Nigeria. Patients were clinically grouped into Graves' disease (GD) (n = 69), simple non-toxic goitre (SNTG) (n = 21), toxic nodular goitre (TNG) (n = 8) and suspected Hashimoto's thyroiditis (HT) (n = 6). Blood donors without thyroid disease (n = 100) acted as controls.

TgAb and TPOAb were found in 4% and 7%, respectively, of healthy adult controls, 11.6 and 76.8% of patients with GD, 25% and 12.5% of patients with TNG and 9.52% and 14.29% of patients with SNTG. TPOAb testing confirmed HT in six patients, and identified two further cases that would have been misdiagnosed without antibody testing.

Thyroid autoimmunity appears more common in these Nigerian patients than in previous reports from Africa, and TPOAb was significantly associated with auto-immune thyroid disease. The clinical utility of these antibody measurements requires further evaluation in a wider African population.