Findings

The left image shows several amebic trophozoites scattered among inflammatory cells in an ulcer bed. The right image shows a PAS stain, which stains glycogen in amebae deep red. Note that the trophozoites are distinctly larger than leukocytes (about 20-30 mm in diameter or several times larger than leukocytes). The organisms are distributed along the "cutting edge" of the ulcer.

Impression

Colon, amebic colitis and amebic trophozoites

Pathology Pointer

PAS stain is useful in detecting the presence of amebic organisms.

Preparation

Fixed; H&E stain; Fixed, stained with PAS stain

View

Light micrograph

Specimen

Colon

Image Credit

Katsumi M. Miyai, M.D., Ph.D
Department of Pathology
School of Medicine
University of California, San Diego