Acute lymphadenitis

This code represents an acute inflammatory condition of the lymph nodes, typically characterized by swelling, tenderness, and sometimes redness in the affected area. It is often a localized response to an infection or inflammation elsewhere in the body, as the lymph nodes filter pathogens and cellular debris.

Apply this code when documentation indicates a sudden onset of inflamed and painful lymph nodes. Common scenarios include bacterial or viral infections, such as pharyngitis, skin infections, or mononucleosis, where the regional lymph nodes become acutely reactive. Documentation should specify "acute" and "lymphadenitis."

• Differentiate from chronic lymphadenitis (289.1) or unspecified lymphadenitis (289.3).
• Always code the underlying cause of the lymphadenitis first, if known and documented (e.g., streptococcal pharyngitis).
• Specify the anatomical location of the affected lymph nodes if documented, using a more specific code if available within the ICD-9-CM framework (e.g., mesenteric lymphadenitis).