Thyroid Disorders in Central Ghana: The Influence of 20 Years of Iodization

Table 5

Diagnostic criteria of various thyroid disorders.

Thyroid disease	Diagnostic criteria
Nodule
Single nodule	Normal thyroid volume with a single nodule > 3 mm in diameter
Multiple nodules	Normal thyroid volume with ≥2 nodules > 3 mm in diameter
Goiter
Diffuse	Diffusely increased left and right lobes without nodules on ultrasound
Nodular	Asymmetrical increased left and right lobes or no increase size on ultrasound; irregular dark dense echoes and numerous nodules throughout the thyroid gland
Hyperthyroidism	TSH < 0.25 Miu/mL, FT4 > 24 pmol/L, or FT3 > 6.8 pmol/L
Hypothyroidism	TSH > 5.0 Miu/mL, TSH < 12.0 pmol/L
Autoimmune thyroid disease
Graves’ disease	Hyperthyroidism, diffuse goiter on ultrasound, TPOAb > 34 U/mL, or TRAb >5 U/mL
Hashimoto’s thyroiditis	Hypothyroidism, TPOAb > 34 U/mL, or TGAb > 115 U/mL Diffuse goiter on ultrasound without history of thyroid surgery
Reference ranges	FT3: 3.7–10.4 pmol/L, FT4: 7.5–21.1 pmol/L, TSH: 0.25–5.0 IU/mL, TPOAb: >5.6 U/L, TRAb > 4.2 U/L
TRAb: thyroid receptor antibody

This diagnostic criterion has been in place since 2004 and has not changed since its institution. Previously diagnosis was made mainly using clinical examination backed by thyroid function tests.