*75 year-old male with hypercalcemia and chronic renal failure.
What is the most likely diagnosis?
1. Parathyroid adenoma
2. Lymph node
3. Eccentric thyroid nodule
4. Parathyroid hyperplasia
Answer
Answer: Parathyroid adenoma secondary to chronic renal failure.
Case Discussion:
Ultrasound and Doppler images show bilateral parathyroid adenomas.
Parathyroid adenoma is benign tumour of the parathyroid gland. It is the most common cause of primary hyperparathyroidism. Chronic renal failure is the cause of secondary hyperparathyroidism. Prolonged stimulation of the hyperplastic glands can eventually lead to autonomy in endocrine and cellular activities.
Parathyroid adenomas are usually oval or bean-shaped; however larger ones can be multilobulated. The majority of them is juxtathyroid and located immediately posterior or inferior to the thyroid gland. The vast majority of them are solitary.
They tend to be homogeneously hypoechoic lesions located juxtathyroid, an echogenic thyroid capsule separating the thyroid from the parathyroid can be seen on ultrasound. Doppler ultrasound can generally demonstrate a characteristic extrathyroidal feeding vessel, entering the gland at one of the poles.
References:
1. Wieneke JA, Smith A. Parathyroid adenoma. Head Neck Pathol. 2008;2 (4): 305-8.
2. Abikhzer G, Levental M, Rush C. High resolution MRI in the detection of an intrathymic parathyroid adenoma. Br J Radiol. 2006;79 (945): e78-80.
3. Johnson NA, Tublin ME, Ogilvie JB. Parathyroid imaging: technique and role in the preoperative evaluation of primary hyperparathyroidism. AJR Am J Roentgenol. 2007;188 (6): 1706-15.
4. Hoang JK, Sung WK, Bahl M et-al. How to perform parathyroid 4D CT: tips and traps for technique and interpretation. Radiology. 2014;270 (1): 15-24.