<prompt> Positive acid schiff macrophages seen in ?Whipples diseaseCrohns diseaseAIDNone of the above  <response>: The traditional laboratory diagnosis is based on light microscopy, which shows diastaseresistant, periodic acid-Schiff PAS-positive, non-acid-fast granules in ... The distinction could be made by acid-fast staining, which is positive for patients infected with M. avium and negative for those with Whipple;s disease. REF : HARRISONS 21ST ED 