Pollen grains in stool examination may lead to misdiagnosis for the parasite ova: 3 case reports.

ABSTRACT

Three cancer patients were admited in Siriraj Hospital for chemotherapy. Routinely, the blood, the urine and stool examination have to be done for checking up / excluding other diseases. In the stool examinations of these patients, light microscopically revealed abundant oval-shaped organism-like structures. They looked like the ova stage of several parasites which could not give the diagnosis by the light microscopic level. Therefore the ultrastructural examination was performed by scanning and transmission microscopes. The TEM revealed clearly that they were not of animal structure because their walls were made up of plant tissue - cellulose. They were concluded to be the pollen grains of plants by comparing to the figure and description from textbooks of palynology, the study of pollen grains. They may be the pollen grains of the herbal medicine which were consumed by the cancer patients as an alternative treatment of the cancer. If light microscopic level cannot give the exact diagnosis, electron microscopy may be helpful.