Hemiagenesis of Right Hemithyroid with Left Lobe Multinodular Goitre

Aims: To present the case of a patient with an uncommon congenital abnormality and discuss it’s consequence and management.

Presentation of Case: We present the case of a 62 year old female patient with no thyroid function abnormalities and no previous neck surgery who was sent to our outpatient clinic for a left sided neck mass with associated discomfort. An ultrasound revealed a left sided multinodular goitre and the absence of the right lobe. A computed tomography scan confirmed these findings. A fine needle aspiration cytology excluded malignancy. A total thyroidectomy was performed and the patient prescribed levothyroxine. There were no intraoperative or postoperative adverse events and the patient remains asymptomatic four years later.

Discussion: Thyroid gland hemiagenesis is a rare congenital disorder consisting in the absence of a thyroid lobe. Left lobe agenesis is the most frequent and females are more commonly affected. Interestingly, thyroid-stimulating hormone and free T3 levels are higher in individuals with this condition and higher risk of thyroid disease has been suggested.

Conclusion: Thyroid gland hemiagenesis is rare. Patients are usually asymptomatic and the condition is found incidentally during screening tests or exams driven by other pathology. It’s existence should be recognized so that patients can be well studied and treated.