Thais Milioni Luciano, Camila Freitas Oliveira
We report a rare case of thyroid abscess associated with transient hyperthyroidism in a previously healthy adolescent. A 14-year-old girl presented with anterior neck pain progressing to swelling, fever, erythema, asthenia, and weight loss over 12 days. Imaging revealed a large abscess in the left thyroid lobe with tracheal deviation. Laboratory tests showed thyrotoxicosis. The patient underwent two drainage procedures, received antibiotic therapy, and a short course of antithyroid medication, evolving with complete clinical and biochemical recovery. Thyroid abscess should be considered in cases of painful cervical swelling associated with hyperthyroidism, as thyroid function may normalize after appropriate treatment.