KISSING SUPERIOR PARATHYROID GLANDS: A CASE REPORT

Abstract

Parathyroid glands are responsible for maintaining the calcium level in blood and usually a pair of superior and inferior parathyroid glands are located in the thyroid gland. Parathyroid glands are smaller and have variations in their size, shape, number and location. Thus, it is difficult to identify the parathyroid gland and leads to its accidental removal during thyroidectomy. This case report is an incidental finding of two superior parathyroid glands in the left lobe of thyroid gland in 68-year female cadaver. Both superior parathyroid glands were located at the first tracheal ring, 2 mm in size, circular in shape, tan yellow in colour, covered by a thin capsule and separated from each other in a distance less than 1 mm. They appear similar as a twin pair and seems to kiss each other. Both were confirmed by the histological method as parathyroid tissues. Superior parathyroid gland developed from the dorsal wing of fourth pharyngeal pouch, get detached from its origin and assumed a relatively constant final location either at the cricothyroid junction or at first tracheal ring. In this present case, the dorsal wing of the fourth pharyngeal pouch have undergone earlier embryological division into two separate superior glands during its descent to the cervical region in the left side. Embryological development of thyroid gland is linked with the development of parathyroid, thymus and ultimobranchial body. Thyroid gland developed from two sources. The median one contributes to thyroid isthmus and parts of the lateral lobe of thyroid. Lateral thyroid lobes derived its contributions from the caudal pharyngeal endoderm of the 4th and 5th pharyngeal pouches. The fusion of median and lateral thyroid forms the Zuckerkandl’s tubercle. Superior parathyroid gland might have travelled along the superior border of isthmus and any changes in the development of thyroid might have influence in the development of parathyroid glands. Up to now a very few cases of kissing parathyroid glands are reported in the literature and this will provide an additional anatomical information of kissing superior parathyroid glands. KEY WORDS: Kissing superior parathyroid glands, Complications of thyroidectomy, Parathyroidectomy, Cricothyroid junction, Twin parathyroid.