Clinical Characteristics of Patients with Subacute Thyroiditis in a Tertiary Hospital

Introduction: Subacute granulomatous thyroiditis or subacute thyroiditis (ST) is characterized by neck pain or neck tenderness and physical examination usually shows diffuse enlargement and tenderness of the thyroid gland. Its etiology often involves a viral infection and ST manifestations occur during the recovery phase of this infection. In this study, we conducted a retrospective data review of 24 patients diagnosed with ST who were followed at our clinic. Patients and Results: Twenty-four patients (18 females, 6 males) with a mean age (±SD) of 41±10 years (min-max: 33-71) were followed. There was no significant age difference between males and females. Laboratory findings were as follows: mean sT4 value 2.7±1.5 ng/dL, sT3 5.5±3.3 pg/ml, TSH 0.2 ±0.4 mlU/mL, erythrocyte sedimentation rate (ESR) 82±27 mm/h, C-reactive protein (CRP) 56.4±36.5 mg/L, average leukocyte count 8762±2496/ mm 3 , absolute neutrophil count 5940±2390/ mm 3 . One patient had elevated anti-thyroid peroxidase (Anti-TPO) and four patients had elevated anti-thyroglobulin (Anti-Tg) antibody levels. The mean time from the onset of an upper respiratory tract infection until ST diagnosis was 39±28 days (min-max: 7-90), the mean duration of follow-up was 200 ±125 days (min-max: 30-370) and the mean duration of clinical manifestations of ST was 130±38 days (min-max: 65-195). Following a ST episode, 19 patients were euthyroid and 3 patients were hypothyroid. The outcome was unknown in 2 patients. Conclusion: ST affects daily life performance adversely due to symptoms of severe neck pain and difficulty swallowing. As can be seen in the case of our patients, the diagnosis of ST is rather difficult unless it is actively sought and on average, it takes 39 days to reach a definite diagnosis. Thus, ST should be considered in the presence of unexplained neck pain with ESR and CRP elevations.