Many conditions can cause enlarged preauricular lymph nodes, with local tissue or organ infections being one of the most common factors, such as lymphadenitis, blepharitis, otitis media, gingivitis, mumps, tonsillitis, etc.
In addition, other non-infectious diseases such as lymphoma, leukaemia, nasopharyngeal carcinoma, systemic lupus erythematosus and nodular disease should also be ruled out to avoid delaying treatment; if there are multiple swollen lymph nodes throughout the body, the possibility of lymphoma is highly suspected and a lymph node biopsy is required for definitive diagnosis if necessary.