An 8 year old HIV-infected boy with tuberculous lymphadenitis (scrofula). Copious amounts of pus spontaneously drained from this lesion. In an immunocompromised child other causes of lymphadenitis include infections with gram-positive bacteria, atypical mycobacterium and Bartonella henselae (cat scratch disease); malignancies such as lymphoma; masses such as branchial cleft cysts or cystic hygromas masquerading as lymph nodes; and adenitis due to HIV itself.