Acute Suppurative Thyroiditis in Childhood: An Atypical Presentation

Abstract

Neck stiffness is a common clinical sign in children presenting to the emergency department that may indicate a wide variety of diagnoses. Acute suppurative thyroiditis (AST) is an infection of the thyroid gland caused by a bacterium, virus, or, less commonly, fungus. It presents as an acute or subacute development of an anterior cervical mass, with associated inflammatory signs. The pressure upon neck muscles may be reflected as a limitation of cervical mobility. AST is often preceded by an upper respiratory tract infection, and pyriform sinus fistula is the most common predisposing factor. It is particularly uncommon in the pediatric age, with limited cases reported in the literature. Therefore, a heightened suspicion is required for proper diagnosis and timely intervention, due to its high mortality. Prompt treatment with broad-spectrum parenteral antibiotic therapy and drainage is mandatory to prevent the numerous complications associated, namely, mediastinitis and sepsis. We report the case of a two-year-old female child admitted with a two-week history of intermittent high-grade fever and sore throat, followed by prostration and limitation in neck movement on admission. Examination revealed neck stiffness with positive Kernig and Brudzinski signs. The laboratory tests showed elevated inflammatory parameters. Cranial computed tomography (CT) scan and lumbar puncture were normal. On day 2 after admission, an anterior cervical mass with slight signs of fluctuation was detected. Ultrasound was compatible with a hemorrhagic/overinfected thyroid nodule, and the patient was started on broad-spectrum antibiotics. Due to clinical worsening, a cervical CT scan was performed, which documented a thyroid abscess with extension into the retropharyngeal space. She underwent surgical drainage, and Streptococcus anginosus and mixed anaerobes were isolated, sensitive to ongoing antibiotherapy. On multidisciplinary follow-up, an esophageal barium study, laryngoscopy, and cervical magnetic resonance imaging (MRI) were performed, revealing no anatomical defects. AST is a rare disease in children, but potentially fatal, so its early recognition and treatment are essential. We aim to draw attention to this disease and its differential diagnosis to reduce the associated morbimortality.

Keywords: acute suppurative thyroiditis; endocrine emergency; pyriform sinus fistula; recurrent neck mass; thyroid abscess.

Figure 1. Thyroid ultrasound

Thyroid ultrasound revealed a lobed heterogeneous iso- and hypoechoic mass, sized 2.8x3.0x3.7 cm, at the left thyroid lobe.

Figure 2. Cervical mass with inflammatory signs

An anterior cervical mass of rubbery consistency with signs of fluctuation was detected on day 2 after admission.

Figure 3. Cervical CT scan: coronal view

A cervical CT scan revealed a thyroid abscess, measuring 4.3x1.5x2.4 cm, with interior gas bubbles suggestive of anaerobic infection. CT: computed tomography

Figure 4. Cervical CT scan: axial view

A cervical CT scan revealed a collection that caused the left deviation of the trachea and extended into the retropharyngeal space. CT: computed tomography

Figure 5. Surgical drainage of thyroid abscess