Suppurative lymphadenitis is a common type of soft tissue infection in children believed to be due to transportation of invading microorganisms (initially penetrating from mucosa or skin of the head or neck most commonly) to afferent lymph nodes. In the case of pyogenic organisms (Staphylococcal or Streptococcal spp), neutrophils are recruited to the lymph node, resulting in rapid swelling, capsular distension, edema, and eventual tissue necrosis with potential abscess formation. There may be overlying erythema of the skin and lymph node drainage.

Suppurative lymphadenitis is most commonly unilateral in presentation, whereas the majority of cases of acute cervical lymphadenitis (the most common location for acute lymphadenitis in children) are bilateral. Viral upper respiratory tract infections (most commonly) and streptococcal pharyngitis and are the primary causes of bilateral nonsuppurative lymphadenitis.

The most common bacterial causes of suppurative lymphadenitis are Staphylococcus aureus and Streptococcus pyogenes, accounting for between 40% and 89% of cases. Other infectious etiologies for consideration should include group B Streptococcus (in infants between 7 and 89 days old and in older patients with appropriate epidemiology), Yersinia, Bartonella henselae (cat-scratch disease), tuberculosis, toxoplasmosis, and lymphogranuloma venereum. Other less common causes of this disease include tularemia, herpes simplex virus (HSV), Erysipelothrix rhusiopathiae, Bacillus anthracis, nocardia, sporotrichosis, and actinomycosis. This condition can affect both adults and children and cause both acute to subacute / chronic infections.

As mentioned above, in children, cervical lymph nodes are most often affected. The groin is another common area to have affected lymph nodes, particularly in adults.

Symptoms include asymmetric tender lymphadenopathy, overlying erythema, and drainage from the affected lymph node. Patients can also have fever and other manifestations of systemic infection. Ultrasonography can be used to assess for abscess formation and to guide fine needle biopsies. Treatment depends on the causative organism and includes oral or intravenous (IV) antibiotics, incision and drainage, or surgical excision of affected lymph nodes.