Diagnosis and treatment of persistent and recurrent hyperparathyroidism

Reasons for postoperative persistence of primary hyperparathyroidism (pHPT) are missed parathyroid adenoma, incomplete removal of multiple altered par arthyroid glands, and rare variants of localisation. A reoperation is indic ated in symptomatic patients if calcium serum levels are elevated above 2.9 mmol/l. Preoperatively, cervical sonography and Tc-99m sestamibi scintigra phy should be carried out. Additionally, selective venous blood sampling an d nuclear magnetic resonance tomography can be of use. After successful loc alization, a unilateral approach is advisable. If position remains unclear, bilateral exploration is required. In secondary hyperparathyroidism (sHPT) , renal function is crucial for development of recurrence. For postoperativ e persistence, identification of less than four pararthyroid glands or leav ing of the thymus are the main reasons. Before reoperation it has to be cla rified if parathyroid hyperfunction is caused by persisting cervical or med iastinal tissue, or if hyperfunction of autotransplanted tissue in the fore arm is evident. Diagnostic and operative procedures are similar to those us ed in pHPT.