General Stool Examination GSE

Collection of samples
If a faecal sample is not properly collected and taken care of before examination, they will be of little or no value for accurate diagnosis. This is especially true if protozoa are present. Amoebic trophozoites begin to degenerate 1-2 hours after passage, as do flagellate trophozoites. Cysts will deteriorate if the faecal specimens are left standing for many hours or overnight, especially at high temperatures.
Helminth eggs and larvae are less affected by the age of the specimen than are protozoa. Nevertheless, changes may occur that could affect their identification. eg, hookworm larvae may become embryonated and larvae may hatch from the eggs risking confusion with Strongyloides larvae. Larvae themselves may disintegrate thus making their identification difficult.
To ensure that good specimens are provided for examination, it is important to note the following points.
1. A clean dry container must be used for the collection of faecal samples. Urine and water will destroy trophozoites, if present, and the presence of dirt also causes identification problems.
2. Ideally the specimen should be brought to the lab as soon as it is passed, to avoid deterioration of protozoa and alterations of the morphology of protozoa and helminths.
3. The specimen container should be clearly labelled with the patients name, date, and time of passage of the specimen.
4. An amount of stool adequate for parasite