Endocrine Abstracts

Background: The aim of radioiodine treatment is to ameliorate hyperthyroidism, with minimal risk of hypothyroidism. The Royal College of Physicians recommends the administration of 400–550 Mbq for Grave’s disease and 550–600 Mbq for toxic multinodular goitre.

Aim: Our audit aimed to analyze the results of our current practice of radioiodine treatment, and also to compare it with the published results of success rate and hypothyroidism.

Method: Retrospective case record review of patients who received radioiodine treatment for thyrotoxicosis between November 2005 and November 2006. One year follow up data was analysed.

Results: Of the 40 patients, 20 patients (50%) had multinodular goitre (MNG), 18(45%) had Grave’s disease (GD) and 2 (5%) had Toxic adenoma.

Twenty-nine out of 40 patients (72.5%) were female and the median age was 64.5 years. The patients with GD were younger than those with MNG (Median age GD 54 years vs MNG 73 years). Median Radioiodine dose for GD and MNG patients were 385 and 391 Mbq, respectively (range 375–847 Mbq).The median duration for 1st follow up was 3.5 weeks (range 1–9 weeks). After radioiodine therapy 23 (57.5%) were hypothyroid, 10 (25%) were euthyoid and 7 (17.5%) patients have sub clinical hyperthyroidism (80% MNG and 20% Grave’s). The median duration for post-radioiodine hypothyroidism was 13 weeks (range 6–56 weeks). Only two patients (5%) failed to radioiodine treatment and received 2nd dose of RAI and both have GD. Of the 23 patients who became hypothyroid after radioiodine, 15 (65%) were had GD and 8 (35%) had MNG. One patient was lost to follow up after radioiodine treatment.

Conclusion: Our audit showed very high success rate (95%) for radioiodine treatment; higher than the published results (60–84%). We used lower dose than recommended dose (<400 Mbq) of radioiodine for patients with toxic MNG with better results.