Lymph node: Mycobacterium avium-intracellulare

Mycobacterium avium-intracellulare (MAC) infection This is a high power view of a section of a lymph node from an HIV-positive adult with a Mycobacterium avium-intracellulare infection. The macrophages are spindle-shaped and contain abundant acid-fast bacilli (AFBs). There is no necrosis. This histology is similar to that of a histoid lesion in leprosy. Ziehl-Neelsen (ZN) stain.