A 48-year-old woman was vaccinated with quadrivalent lytic influenza virus vaccine. Seven days later, tenderness pain and mass with tenderness pain appeared on the left side of the thyroid gland, which was diagnosed as subacute thyroiditis. The patient received celecoxib capsules 200 mg orally twice daily, external application of Pingying powder (平瘿散), and oral administration of traditional Chinese medicine decoction. The pain and mass disappeared after 21 days of treatments. One week later, similar symptoms occurred on the right side of the thyroid gland, the same dose of celecoxib capsules was given, but it was ineffective. So, it was replaced by prednisone acetate tablets 20 mg orally once daily. Twenty-five days later, the pain was relieved and the neck mass reduced. It was considered that the patient′s subacute thyroiditis was possibly due to quadrivalent lytic influenza virus vaccine.

A 48-year-old woman was vaccinated with quadrivalent lytic influenza virus vaccine. Seven days later, tenderness pain and mass with tenderness pain appeared on the left side of the thyroid gland, which was diagnosed as subacute thyroiditis. The patient received celecoxib capsules 200 mg orally twice daily, external application of Pingying powder (平瘿散), and oral administration of traditional Chinese medicine decoction. The pain and mass disappeared after 21 days of treatments. One week later, similar symptoms occurred on the right side of the thyroid gland, the same dose of celecoxib capsules was given, but it was ineffective. So, it was replaced by prednisone acetate tablets 20 mg orally once daily. Twenty-five days later, the pain was relieved and the neck mass reduced. It was considered that the patient′s subacute thyroiditis was possibly due to quadrivalent lytic influenza virus vaccine.