parapharyngeal abscess

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with fever and left neck stiffness. Axial CT with contrast of the neck shows a round, well circumscribed, low density lesion in the left parapharyngeal space that has mild peripheral enhancement.The diagnosis was left parapharyngeal abscess.

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Parapharyngeal abscesses are deep neck abscesses involving the parapharyngeal space. It is a serious medical condition, potentially fatal, and requires prompt diagnosis and treatment.

Epidemiology

A person of any age can develop a parapharyngeal abscess, but it is most commonly seen in children and adolescents . Immunocompromised adults are also at an increased risk .

Clinical presentation

Presentation is variable, the first symptoms of a parapharyngeal abscess are similar to those of uncomplicated acute pharyngitis or tonsiliits (fever, sore throat, nasal voice, dysphonia, cervical lymphadenopathy). Progression of the signs and symptoms is key as it pertains to inflammation and obstruction of the upper airways and/or gastrointestinal tract and there may be dysphagia, dyspnea, stridor, neck stiffness, drooling, trismus and/or chest pain.

Pathology

Usually, parapharyngeal abscesses arise secondary to oropharyngeal infections that spread either by direct continuity or by lymphatic drainage:

acute and chronic tonsillitis
bursting of peritonsillar abscess
dental infection usually comes from the lower last molar tooth
Bezold abscess
petrositis
spread from other deep head and neck spaces (e.g. parotid, retropharyngeal or submandibular spaces)
secondary to penetrating trauma of the neck
iatrogenic e.g. injection of local anesthetic for tonsillectomy or mandibular nerve block

Treatment and prognosis

When a parapharyngeal abscess is detected, treatment should commence immediately. It can usually be treated with broad-spectrum parenteral antibiotics and surgical drainage. Occasionally, small abscesses can be treated with IV antibiotics alone .

Complications

Parapharyngeal space infections are important causes of morbidity and mortality due to possible complications including :

acute edema of larynx with airway obstruction
thrombophlebitis of jugular vein with septicemia (Lemierre syndrome)
spread of infection to retropharyngeal space
spread of infection to mediastinum along the carotid space or danger space
mycotic aneurysm with possible subsequent rupture of the internal carotid artery
carotid blowout with massive hemorrhage