What is Cervical Phlegmon?

Cervical Phlegmon: Definition and Management

Cervical phlegmon refers to a diffuse inflammatory process in the neck's deep tissues and spaces, characterized by edema and inflammation without a well-defined fluid collection for drainage. 1

Definition and Characteristics

• Cervical phlegmon is an inflammatory mass with ill-defined borders consisting of mixed fat and/or soft tissue density, usually associated with penetrating disease or complex infections 1
• The term "phlegmon" has been discouraged in some contexts due to its ambiguous definition, as it doesn't clearly distinguish between drainable (abscess) and non-drainable (localized inflammation) conditions 1
• Cervical phlegmon can be associated with retropharyngeal edema, particularly in conditions like Kawasaki Disease 1

Anatomical Considerations

• Cervical phlegmons most commonly affect the carotid and parapharyngeal spaces 2
• They can spread through the deep fascial planes of the neck, potentially extending to vital structures 2
• In severe cases, inflammation can extend along fascial planes toward the mediastinum, creating life-threatening complications 3

Etiology

• Most commonly caused by bacterial infections, with streptococci and staphylococci being the predominant pathogens 2
• Can develop from:
  • Odontogenic (dental) infections 2
  • Oropharyngeal inflammation 3
  • Lymph node inflammation (colliquation of inflammatory changed lymph nodes) 3
  • Foreign body perforation of the esophagus 3
  • Surgical complications (rare) 4

Clinical Presentation

• Swelling and pain in the neck region 2
• Fever and constitutional symptoms 3
• Potential skin changes over the affected area (though not always present) 3
• May present with diffuse involvement across different regions of the head and neck 2
• In severe cases, can lead to systemic inflammatory response and sepsis 4

Diagnosis

Imaging

• CT scan is the gold standard for diagnosis of cervical phlegmon 2
• MRI with IV contrast is highly sensitive for detecting paraspinal and epidural inflammation when spinal involvement is suspected 1
• Radiographs have limited value as they have low specificity and are often normal in early disease 1

Laboratory Tests

• Elevated inflammatory markers (ESR, CRP, WBC count) 1
• Blood cultures may help identify causative organisms 3

Management

Medical Treatment

• Immediate broad-spectrum antibiotics are the cornerstone of treatment 2, 3
• Metronidazole is often added to cover anaerobic bacteria 2
• Pain management and supportive care 2

Surgical Intervention

• Surgical drainage is indicated when there is:
  • Evidence of abscess formation 3
  • Progression despite antibiotic therapy 3
  • Compromise of vital structures 3
• Two main surgical approaches:
  • Common abscess incision for localized collections 2
  • Broad incision along sternocleidomastoid muscle for more extensive involvement 2

Complications

• Spread to adjacent vital structures (carotid artery, jugular vein) 3
• Extension to mediastinum (mediastinitis) 3
• Airway compromise 3
• Sepsis and systemic inflammatory response syndrome 4
• Mortality risk if not treated promptly and appropriately 3

Important Distinctions

• Do not confuse cervical phlegmon with phlegmasia cerulea dolens (PCD), which is an entirely different condition involving massive venous thrombosis of the extremities 5, 6
• Cervical phlegmon should be distinguished from a true abscess, which has a well-defined fluid collection with rim enhancement on imaging 1

Monitoring and Follow-up

• Close monitoring of clinical response to antibiotics 3
• Serial imaging may be necessary to evaluate progression or resolution 2
• Vigilance for potential complications, especially mediastinal extension 3