Ultrasonographic aspects of goiter: A comparative epidemiological study between Chinese and Congolese pregnant women who consulted the department of endocrinology for thyroid disorders

Aims: Thyroid pathologies are correlated to genetics, environmental and reproductive factors including pregnancy that has an impact on the thyroid gland, especially when it occurs on an iodine deficient ground. This study aimed to compare the ultrasonographic aspects of goiter in Chinese pregnant women with those of Congolese who consulted the department of endocrinology for thyroid disorders. Methods: Eighty pregnant women (40 Congolese and 40 Chinese) were retrospectively evaluated between February 2016 and March 2017 at the University Clinics of Kinshasa in Democratic Republic of Congo, and at the Qianfoshan Hospital in People’s Republic of China. Thyroid ultrasound was performed using a 7.5-9MHz frequency linear-array transducer with a device of a Doppler function. Results: Mean thyroid volume was recorded to be 12.1 ± 6.2 mL (range 4-28.6 mL) and 67.4 ± 7.7 mL (4-392.1 mL) in the Chinese group and Congolese respectively (p<0.001). 85% of Congolese subjects had goiter, while only 12.5% of Chinese subjects had it. Goiters were associated with sonographic Hashimoto’s thyroiditis in the Chinese group, while 91.2% and 8.8% of goiters were respectively nodular and diffuse in the Congolese group. The thyroid parenchyma in the Chinese group was especially hypoechoic and heterogeneous with variable degree of vascularization, while in the Congolese group, beside hypoechogenicity and heterogenicity, we noted a normal vascularization. Conclusions: Ultrasonography detected a higher prevalence of goiter in the Congolese pregnant women than in the Chinese.