Bone mineral density analysis in patients with primary hyperparathyroidism associated with multiple endocrine neoplasia type 1 after total parathyroidectomy.

OBJECTIVE: Limited data have been reported on the effect of parathyroidectomy (PTx) on bone mineral density (BMD) in the setting of patients with hyperparathyroidism (HPT) associated with multiple endocrine neoplasia type 1 (MEN1). This study investigates the impact of total PTx on BMD in patients with HPT/MEN1.

DESIGN AND PATIENTS: A case series study was performed in a tertiary academic hospital. A total of 16 HPT/MEN1 patients from six families harbouring MEN1 germline mutations were subjected to total PTx followed by parathyroid auto-implant in the forearm.

MEASUREMENTS: Bone mineral density values were assessed using dual-energy X-ray absorptiometry.

RESULTS: Before PTx, reduced BMD (Z-score <-2.0) was highly prevalent in the proximal one-third of the distal radius (1/3 DR) (50%), lumbar spine (LS) (43.7%), ultradistal radius (UDR) (43.7%), femoral neck (FN) (25%) and total femur (TF) (18.7%) in the patients. Fifteen months after PTx, we observed a BMD improvement in the LS (from 0.843 to 0.909 g/cm(2); +8.4%, P = 0.001), FN (from 0.745 to 0.798 g/cm(2); +7.7%, P = 0.0001) and TF (from 0.818 to 0.874 g/cm(2); +6.9%, P < 0.0001). No significant change was noticed in the 1/3 DR and UDR after PTx.

CONCLUSIONS: This data confirmed BMD recovery in the LS and FN after PTx in HPT/MEN1 patients. We also documented a significant BMD increase in the TF and no change in both the 1/3 DR and UDR BMD after PTx. Our data suggest that LS and proximal femur are the most informative sites to evaluate the short-term BMD outcome after PTx in HPT/MEN1 subjects.