A rare case presentation of a common condition: A large laryngeal gouty tophus

Abstract

Laryngeal gout is an exceedingly rare manifestation of advanced, poorly controlled gout. It is characterized by the deposition of gouty tophi within various laryngeal structures. Similar to peripheral joints, monosodium urate crystals develop due to high concentrations of serum uric acid. When localized to the laryngeal region, tophi can induce a range of symptoms and complications, including hoarseness, dysphagia, respiratory distress, and infection. Alternatively, it may present as an asymptomatic anterior neck mass. The thyroid cartilage, true vocal cords, arytenoids, and cricoarytenoid joints have all been previously described as areas of involvement. In this case report, we describe the presence of a large, asymptomatic laryngeal gouty tophus situated between the hyoid bone and thyroid cartilage that was initially interpreted as ectopic thyroid tissue on CT imaging. Management typically includes urate-lowering therapy, reduction in alcohol and red meat consumption, and potential surgical intervention for obstructive symptoms. This case underscores the importance of considering laryngeal gouty tophi in patients with chronically uncontrolled hyperuricemia presenting with anterior neck masses.

Introduction

Gout is an inflammatory arthritic condition in which monosodium urate crystals precipitate within the synovial membrane or cartilage, causing severe, sharp pain in the involved joint. In some cases, tophi—large accumulations of these crystals surrounded by immune cells and fibrovascular tissue—can develop within the joint space and present as painful nodules with bone erosion and cartilage damage [1]. Bony erosion typically occurs due to enhanced osteoclast formation adjacent to the tophi. Gouty tophi are most commonly found in the first metatarsophalangeal (MTP) joint, as well as the olecranon bursa, Achilles' tendon, ankles, and knees [2].

Elevated serum uric acid is the most significant risk factor for developing gout, with high alcohol and red meat consumption serving as common triggers for hyperuricemia. Joint trauma and acute illness can also serve as triggers for gout episodes [1]. Additionally, certain ethnicities have a genetic predisposition to gout, including the Hmong population, who exhibit a higher prevalence and younger age of onset, often presenting in patients younger than 30 years old [3]. We present a case of a large laryngeal gouty tophus in a Hmong male with chronically uncontrolled gout that was initially misidentified as ectopic thyroid tissue.

Case presentation

A 29-year-old Hmong male with a history of gout and chronically elevated serum uric acid levels (> 10 mg/dL) presented to his primary care provider with pain and swelling in his right elbow of several weeks' duration. During the examination, the provider noticed anterior neck swelling; the patient admitted to progressive swelling in that area for approximately one year. The patient noted a vague family history of thyroid disorders but denied any personal history. The patient was started on a prednisone taper, referred to rheumatology, and laboratory tests confirmed his TSH and T4 levels were within normal limits.

Due to suspicion of a goiter or enlarged thyroid nodules, a thyroid ultrasound was performed, which revealed an indeterminate structure at the palpable abnormality that the ultrasound echoes could not penetrate (Fig. 1). A CT of the neck was subsequently performed and identified a 4.8 × 3.6 × 2.7 cm mass containing multiple calcifications interposed between the hyoid and thyroid cartilage. This mass demonstrated a broad area of contact extending from the base of the vallecula to the anterior neck, deep to the sternohyoid muscle. The radiologist interpreted the mass as ectopic thyroid tissue, and a fine-needle aspiration (FNA) was recommended. The native thyroid on CT was read as normal, while the abnormality was described as ectopic thyroid tissue (Fig. 2).

Fig. 1.

Ultrasound imaging of the palpable anterior neck abnormality demonstrating an indeterminate structure that could not be penetrated by the ultrasound echoes.

Fig. 2.

Axial and sagittal images demonstrating an anterior multilobulated neck mass measuring approximately 4.8 (Tx) x 3.6 (CC) x 2.7 (AP) cm, with heterogeneous enhancement and multiple calcifications.

Upon evaluation in the rheumatology clinic, the patient was found to have several gouty tophi at multiple sites, including the elbows, wrists, ankles, and knees (Fig. 3), which limited the mobility of his fingers and wrists. The anterior neck mass was also noticeable upon visual inspection (Fig. 4). After re-examining the CT imaging, the mass appeared distinct from the thyroid; a clinical suspicion for a gouty tophus was raised, and the biopsy team was informed. The FNA confirmed the diagnosis of a laryngeal gouty tophus, revealing amorphous material consistent with gout and abundant needle-shaped crystals with negative birefringence under polarizing microscopy. Due to the absence of complications from the laryngeal gouty tophus, medical management was chosen as the initial therapy, involving a titration to allopurinol 500 mg daily, a short oral prednisone course, and colchicine, acetaminophen, and indomethacin as needed for flares.

Fig. 3.

Diffuse gouty tophi on the bilateral knees, left shin, bilateral wrists, and bilateral elbows.

Fig. 4.

Palpable anterior neck mass that was later determined to be a large laryngeal gouty tophus.

Discussion

While gout most commonly affects the first MTP joint and the lower extremities [2], rare cases involving the neck—classified as laryngeal gout—have been reported with involvement of the thyroid cartilage [4,5], vocal cords [[6], [7], [8]], mandible [9], and cricoarytenoid joints [10]. These presentations pose a diagnostic challenge because their symptoms and imaging features may overlap with malignant or inflammatory neck pathologies.

We describe the CT findings of the laryngeal tophus located between the hyoid bone and thyroid cartilage as a multilobulated heterogeneous mass with multiple calcifications. Due to the crystalline structure, ultrasound echoes could not penetrate the mass, resulting in acoustic shadowing. This reflects dense monosodium urate crystal deposition and may serve as a useful diagnostic feature to differentiate tophi from thyroid lesions, which typically demonstrate soft tissue echogenicity.

Additionally, this case highlights the importance of clinical context in the interpretation of imaging findings. In patients with chronically elevated serum uric acid levels, multiple gouty tophi, and an ethnic predisposition, laryngeal gout should be high on the differential diagnosis of anterior neck masses. Accurate differentiation between these two entities is essential, as their management approaches differ substantially. Asymptomatic gouty tophi may be managed with long-term high-intensity urate-lowering therapy, with surgical intervention considered selectively. However, if the tophus causes complications such as airway obstruction [11], dysphagia, hoarseness [6], or infection [5], surgical intervention should be considered as an adjunct to medical therapy, as it has been shown to improve symptoms [11]. Ultimately, a serum uric acid level < 6 mg/dL should be targeted to dissolve existing tophi [12].

Although CT imaging is important to characterize anterior neck masses and the extent of involvement, readily available in-office ultrasound may be used as a rapid method to differentiate gouty tophi from thyroid nodules or thyroid enlargement. Furthermore, FNA biopsy can be used to confirm the clinical suspicion. Given the rarity of laryngeal gout, further research is warranted to better define its true incidence, characteristic imaging features across modalities, and optimal diagnostic pathways. Moreover, prospective studies evaluating long-term outcomes of medical versus surgical management could inform evidence-based treatment guidelines and improve patient care.

Patient consent

Written, informed consent to publish this case was obtained from the patient.