Neck abscess due to extraluminal migration of a pharyngeal foreign body

Clinical History

Neck swelling, overlying erythema, tenderness, fever and chills

Imaging Findings

The patient was admitted to hospital with neck swelling, overlying erythema, tenderness, fever and chills. Her pulse rate was 102beats/ min and her respiratory rate 18 breaths/ min. She was awake and cooperative. The Neurological, Cardiovascular and Pulmonary examination findings were unremarkable. The WBC count was 17000/ muL (75% segmented neutrophils). Two weeks before admission she ate fish and a small fish bone lodged in her oropharynx. She paid no attention to it. Symptoms began five days prior to admission with intermittent fever, chills, neck swelling and overlying erythema. CT revealed a radiopaque density in the right neck. A soft tissue density mass was shown at the same area. The center of the lesion was of lower density. Air bubbles were also noted. Surgical drainage was suggested. Surgery was performed with debridement and drainage of the abscess and the fish bone was removed. Multiple organisms were cultured, including G- bacilli, peptostreptococci and St. viridans.

Discussion

While regional trauma from an ingested foreign body is the leading cause for a retropharyngeal abscess, this is not the case for parapharyngeal abscess. In the majority of cases of parapharyngeal abscess (80%) etiology is unknown. Only a small number of foreign bodies can perforate the upper digestive tract lumen and even less migrate completely extraluminally. Foreign bodies pass through through the mucosal surface of the lumen and may remain embedded in the periluminal tissue, move in the adjoining tissue or perforate adjoining visceral structures, major blood vessels or the thyroid gland. Signs and symptoms of the parapharyngeal abscess include fever, dysphagia, neck swelling, tenderness, stridor, cervical lymphadenitis and drooling. Culture specimens usually have more than one organism. The most common pathogens are St. viridans, St.aureus and St. epidermidis. Surgical drainage, debridement and antibiotic treatment are the treatment modalities of choice. CT is the diagnostic modality of choice and may clarify the diagnosis and define the location and extent of the infection. CT may differentiate between deep neck abscess and neck cellulitis, which is important since neck abscess requires drainage while cellulitis requires antibiotics only. CT may also demonstrate secondary complications and occasionally suggest the etiology of infection. Limitations of CT scanning include difficulty in identifying small foreign bodies, objects with densities similar to surrounding structures and detecting vascular injury.

Differential Diagnosis List

Final Diagnosis

Neck Abscess due to perforation of the upper digestive tract lumen.

URL:	https://www.eurorad.org/case/676
DOI:	10.1594/EURORAD/CASE.676
ISSN:	1563-4086