RADIONUCLIDE IMAGING OF THE PARATHYROID GLANDS TO PREDICT MEDICATION RESPONSE FOR HYPERPARATHYROIDISM IN CHRONIC KIDNEY DISEASE AND DIALYSIS

Introduction:

Secondary and tertiary hyperparathyroidism (HPT) are common in chronic kidney disease (CKD). HPT treatment mostly starts with medication and surgical parathyroidectomy in refractory cases. However, many patients fail medication therapy and delayed HPT resolve might associate with poor quality of life and survival. To date, the suggested marker to indicate timely surgical intervention, apart from the level of plasma parathyroid (PTH) >1000 pg/mL in dialysis patients, is lacking.

Methods:

Medical data of all CKD patients appointed for parathyroid scans with Tc-99m pertechnetate/Tc-99m MIBI in 2023 at King Chulalongkorn Memorial Hospital were reviewed. Factors to differentiate between those responding and not responding to medication were investigated. Medication response was defined as the ability to suppress PTH level within 6 months without surgical parathyroidectomy, to less than 65 pg/mL in non-dialysis or 585 pg/mL in dialysis.

Results:

Forty-one patients, 46% on dialysis and 44% transplant recipients, were included. Those who responded to medication have lower initial PTH (290±310 vs. 1176±1311 pg/mL, p-value 0.002). The higher intensity of early Tc-99m MIBI uptake associates with medication unresponsiveness for both dichotomous (negative/positive stain, p-value 0.028) and polytomous (negative/faint/strong, p-value 0.045) categorizations. In non-dialysis subgroup, initial PTH level is not predictive for response while all patients with positive scans fail medication treatment.

Conclusions:

Radionuclide parathyroid scan intensity could assist the prediction of medication response in CKD-related HPT and might help prioritize patients for surgery referral to prevent adverse outcomes from delayed PTH reduction, especially in non-dialysis subgroup due to the lack of suggested PTH threshold. 

This abstract was submitted for the Nephrology Society of Thailand Annual Meeting 2024. Resubmitting the abstract is permitted by the organizers of the aforementioned meeting.

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.