Infectious Agents
Case 4

Clinical Features
Electron Microscopy
Discussion

Case 1
Case 2
Case 3
Case 4

Electron Microscopy of Infectious Agents

Case 4: Cryptosporidium in the Bile Duct.

Discussion

Cryptosporidium has become a more important human pathogen with the number of people being immunosuppressed for treatment of neoplasms or transplant of organs, and is of concern as an infectious agent in patients with AIDS Transmission electron microscopy will continue to be an important tool to visualize this organism, as well as other pathogens. As pointed out by Orenstein (2), the sensitivity of TEM is remarkable and its specificity is without substitute as a tool for understanding the opportunistic pathogens associated with immunodeficiencies.

Although TEM is not essential to visualize the Cryptosporidia organisms in intestinal biopsies because they are readily identifiable by H & E and Gomori stains (3), it is nice to have the additional imaging capabilities of the electron microscope to distinguish between the stages in the life cycle of the protozoan.

References

1. 1. Casemore, D.P, Sands, R.L., and Curry, A.: Cryptosporidium species a "new" human pathogen. J. Clin Pathol. 38:1321-1336, 1985.
   
2. Orenstein, J.M.: The role of electron microscopy in infectious disease diagnosis. The J. Histotechnol 18:211-224, 1995.
   
3. Orenstein, J.M.: Diagnosis of gastrointestinal diseases in AIDS. Advances in Pathology and Laboratory Medicine, 8: 453-477, 1995.

Case 1

Case 2

Case 3

Case 4