The Analysis Of The Factors Which Lead To Misdiagnosis In 44 Subacute Thyroiditis Cases And Its Strategies

Subacute thyroiditis (SAT) is common clinically and diagnosis of typical cases is not difficult. But in fact, misdiagnosis occurs frequently. The rate of diagnosis recorded by clinical study is 68.5%. So, some patients suffered unnecessary treatment, even surgical intervention. There are 98 in-patients with SAT in our hospital from January, 1990 to October, 2004, 44 cases were misdiagnosed among them. A retrospective review of their medical records was performed. The clinical characteristics of 44 misdiagnosed patients with SAT were analyzed and compared with those of 54 correct-diagnosed SAT cases in the same period in order to find out the reasons and the strategies to avoid misdiagnosis. Methods:The data of 98 SAT in-patients from January 1st, 1990 to October 31st, 2004 were collected and we divided these patients into two groups: 1) misdiagnosed group 2) correct-diagnosed group. These data include the individual conditions, for example sex, age, the first complaint and physical examination, and the assistant examination results, including WBC counting, ESR, CRP, thyroid hormones, ultrasound, fine needle aspiration cytology (FNAC) and so on. Finally we analyzed and compared the data of two groups by statistic means. Results:44 SAT patients were misdiagnosed as upper respiratory tract infection, Tuberculosis, hyperthyroidism, hypothyroidism, multinodular goiter, thyroid adenoma, thyroid cancer and so on. The rate of misdiagnosis is 44.9%. The number of the patients with atypical features in the misdiagnosed group (56.8%) is more than that in the correct-diagnosed group (18.5%) (p<0.001). There are 19 patients misdiagnosed for their different features in the different phrases of SAT (43.2%). The misdiagnosed group has the lower undergone rate of medical examination than the correct-diagnosed group. The undergone rate of the thyroid function, 99mTc scintigraphy, FNAC in the misdiagnosed group is 70.5%, 27.3% and 34.1% respectively. They are much lower than the correct-diagnosed group (98.2%, 100.0% and 100.0%) (P<0.001). Furthermore, in the misdiagnosed group, 28 cases were caused by the incomplete analysis of the examination results and 9 cases'reason is that doctors pay less attention to SAT. Conclusions:The variety clinical presentations of SAT will mislead the doctors, but misdiagnosis can be avoided if they are more careful clinical presentations of SAT. Therefore, we should pay more attention to SAT, choose the correct examinations and exactly evaluate in order to avoid misdiagnosis.