Background Pyriform sinus fistulas (PSFs) are rare congenital anomalies of the third or fourth brachial clefts. Dyspnea is reportedly secondary to compression by a neck mass. However, hoarseness, as the first symptom of PSF, has not yet been reported. Case presentation This report describes an eleven-year-old girl presenting with hoarseness as the first symptom of PSF. Hoarseness occurred 2 days prior to admission. On admission, she had fever, hoarseness, and an elastic soft mass on her left anterior neck. Contrast-enhanced computed tomography of the cervical region demonstrated an abscess partially infiltrating the thyroid gland and an air pocket near the pyriform sinus. Pharyngoscopy revealed swelling of the left arytenoid region, with purulent retention. The left vocal cord was swollen but not paralyzed. Additionally, the laboratory data indicated thyrotoxicosis. Suspecting a PSF infection, parenteral treatment with cefotaxime and dexamethasone was initiated. On the following day, the hoarseness disappeared, and the fever resolved. Four weeks after onset, the thyroid hormone levels returned to the normal range, and a barium esophagogram revealed residual contrast in the left pyriform sinus, leading to a diagnosis of PSF. Conclusion PSF presenting with hoarseness as the first symptom in patients should be considered.

Background Pyriform sinus fistulas (PSFs) are rare congenital anomalies of the third or fourth brachial pouch. Dyspnea is reportedly secondary to compression by a neck mass. However, hoarseness, as the first symptom of PSF, has not yet been reported. Case presentation This report describes an 11-year-old girl presenting with hoarseness as the first symptom of PSF. Hoarseness occurred 2 days prior to admission. On admission, she had fever, hoarseness, and an elastic soft mass on her left anterior neck. Contrast-enhanced computed tomography of the cervical region demonstrated an abscess partially infiltrating the thyroid gland and an air pocket near the pyriform sinus. Pharyngoscopy revealed swelling of the left arytenoid region, with purulent retention. The left vocal cord was swollen but not paralyzed. Additionally, the laboratory data indicated thyrotoxicosis. Suspecting a PSF infection, parenteral treatment with cefotaxime and dexamethasone was initiated. On the following day, the hoarseness disappeared, and the fever resolved. Four weeks after onset, the thyroid hormone levels returned to the normal range, and a barium esophagogram revealed residual contrast in the left pyriform sinus, leading to a diagnosis of PSF. Conclusion PSF presenting with hoarseness as the first symptom in patients should be considered.