Endocrine Abstracts

Objectives: Steroid-dependent subacute thyroiditis (SAT) is a challenging clinical problem. Long-term treatment and high cumulative doses of systemic steroids are associated with high risk of steroid-related complications. The DLISAT study aims to evaluate the efficacy and safety od intrathyroidal dexamethasone injections in chosen groups of patients, comparing the outcomes with standard oral steroid therapy. This paper presents the preliminary results focusing on two patients with steroid-dependent SAT.

Methods: Steroid-dependent SAT was defined as recurrent symptoms upon at least three attempts of steroid dose reduction. Patients with inadequately rapid dose reduction were excluded from the study. The included patients underwent four (Patient 1) and five (patient 2) attempts of dose reduction during 7 and 8 months, respectively. Intrathyroidal injections of 4 mg of dexamethasone (1 ml of solution), with or without 1 ml of 2% lidocaine, were administered into the affected thyroid lobe under ultrasound guidance. Doses were repeated every 2-7 days based on the obtained results. Parameters including pain severity, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), thyroid stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3) and thyroglobulin (Tg) were measured before and after injections. Ultrasound image and shear wave elastography results were analyzed before and after each injection, as well as after therapy completion. Total recovery criteria included resolution of symptoms, normalization of ESR, CRP and thyroid hormones, along with significant reduction of SAT-related thyroid lesions in ultrasound examination.

Results: Excellent response to therapy was observed in both patients, with rapid pain release after the first dose. No side effects except for injection-related discomfort was reported. Complete recovery was achieved after 6 and 7 injections into the affected lobes in Patient 1 and Patient 2, respectively. The whole therapy duration was 27 for Patient 1 and 29 for Patient 2. The dose of dexamethasone required for the total therapy was 24 mg in Patient 1 (one lobe affected) and 56 mg in Patient 2 (both lobes affected).

Conclusion: Intrathyroidal dexamethasone injections demonstrated excellent efficacy and safety in patients with oral steroid-dependent SAT, resulting in rapid symptom relief, short therapy duration, and low steroid doses. This approach seemed to be a great therapeutic tool in patients with symptoms recurrence during reduction of oral steroid dose, and may be considered a first line treatment, especially in patients with high risk of steroid-related complications.