Non-tuberculous mycobacterial adenitis
Non-tuberculous mycobacterial adenitis refers to lymphadenopathy due to mycobacterial infection other than M. tuberculosis.
Epidemiology
Most cases occur in immunocompetent children younger than 5 years of age.
Clinical presentation
Patients present with a firm, painless mass that enlarges over several weeks and develops overlying violaceous skin changes.
Pathology
Etiology
The most common microbiologic cause is Mycobacterium avium-intracellulare complex.
Location
The cervicofacial nodes, especially in the submandibular and parotid region, are most commonly involved.
Radiographic features
Ultrasound
The involved lymph nodes show markedly decreased echogenicity consistent with intranodal liquefactive/cystic necrosis . Nodal matting and adjacent soft tissue edema are also present .
CT and MRI
Contrast-enhanced CT or MRI demonstrates an enlarged nodal mass with central necrosis (rim or heterogeneous enhancement) but characteristically minimal surrounding fat stranding .
Treatment and prognosis
Patients are treated with a combination of surgery (incision and drainage or excision) and antibiotics (for several months), with most achieving cure .
Differential diagnosis
See separate differential articles:
