1. Parathyroid Gland Histopathology M-2 P.E. Wakely, Jr., M.D. Department of Pathology Wexner Medical Center

2. Parathyroid Gland - Objectives Describe the embryology & histology of the parathyroid glands. Define the etiology and clinical features of hyper- and hypo-parathyroidism. Recognize the distinction between parathyroid hyperplasia and parathyroid adenoma.

3. Parathyroid Glands Derived from pharyngeal pouches Inferior glands from 3 rd pouch Superior glands from 4 th pouch Typically 4 glands – 2 on each side Cell Types: Chief cells: pale or clear cytoplasm Oxyphil cells: eosinophilic cytoplasm 30-40 mg. each Two major diseases: hyper- and hypo- PTH

4. Ivar Sandström, MD 1852-1889 26 y/o medical student Uppsala Hospital Discoverer of parathyroid glands Suicide, age 37 yrs.

5. Normal parathyroid

6. Primary HyperParathyroidism  serum PTH levelMobilized Ca ++   serum Ca ++,  serum P Etiology: adenoma – 80% hyperplasia – 15-20% carcinoma – <1 % Clinical Manifestations F:M = 4:1; 50-75 yrs. renal calculi / weakness/fatigue / osteoporosis / bone resorption [osteitis fibrosa cystica] mental status change, seizures

7. Fig. 10-44. Parathyroid hyperplasia. All four glands are enlarged, albeit not to the same extent. Parathyroid hyperplasia

9. Capt C. Martell 1926 the first parathyroidectomy performed in the USA. Over several yrs. had 6 operations in neck for hyperparathyroidism 7 th operation: found tumor in mediastinum. Cured hyperPTH Died 6 weeks later from hypocalcemic- induced hypoparathyroidism.

10. PTH Adenoma

11. Parathyroid adenoma

12. PTH Adenoma

13. PTH Adenoma, Oxyphilic Type

14. PTH Adenoma

15. PTH Adenoma, Clear Cell Type

16. h13 85-90% 5-15%

17. HypoParathyroidism  serum Ca ++ Etiology inadvertent surgical removal, congenital absence, idiopathic atrophy Clinical manifestations tetany [neuromuscular irritability numbness  laryngospasm, seizures] mental status changes, cardiac conduction disturbances: prolongation QT interval

18. Thank you for completing this module. QUESTIONS? Please direct questions to: Paul.Wakely@osumc.edu

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