Negative images due to MAI infection detected in Papanicolaou-stained duodenal brushing cytology

Abstract

Atypical mycobacteriosis of the duodenum was diagnosed by duodenal brush cytology in a woman with AIDS. Smears were fixed in alcohol and stained by the method of Papanicolaou. The cytological characteristics of this disease have been described previously in other cytological specimens such as imprints or fine-needle aspirations stained with Diff-Quik or Wright's stain. We found that alcohol fixation and routine Papanicolaou staining allow observation of numerous foamy and striated macrophages (pseudo-Gaucher cells), as well as negative images both within the cytoplasm of the macrophages and in the background of smears in areas of air-drying artifact. These findings should suggest the diagnosis of atypical mycobacteriosis, and special staining techniques such as PAS and Ziehl-Neelsen are useful in corroborating it. This has not been previously described.