Peak ahead of thyroid 131I uptake ratio in subacute thyroiditis

Objective: To investigate the relationship between the changes of thyroid 131I uptake ratio in subacute thyroiditis and clinical examination. And try to establish a standard to distinguish the low-level 131I uptake ratio caused by subacute thyroiditis and by cystic goiter (or cystadenoma) rupture. Methods: The data of thyroid 131I uptake ratio of 44 cases got according to the clinical nuclear medicine examination standard was reviewed and analyzed. Results: 1. The 131I uptake ratio in 36 subacute thyroiditis patients were lower than the normal level (P<0.001), including 26 peak ahead cases (2h, 3.37±2.53%, 4h 4.54±1.12%, 24h 2.44±1.18%). 2. The 131I uptake ratio in 8 cystadenoma rupture patients decreased apparently, too. But no peak ahead case appeared. Conclusions: The subacute thyroiditis is characterized not only with the apparent decrease of 131I uptake ratio, but also with peak ahead (72.22%)