Use of a single slide trichrome-stained concentrate for the detection of intestinal parasites: Stained concentration procedure for ova and parasites

The detection and identification of intestinal parasites was studied using a single slide of a trichrome-stained concentrate made from a cupric- polyvinyl alcohol (PVA)-preserved specimen. When saline was used in place of formalin in the concentration procedure, it was possible to adequately stain the concentrate with a modified-trichrome stain. This was compared to a more traditional two-slide ova and parasite (OandP) procedure. Of the 1,000 specimens evaluated, a total of 261 parasites were detected using the single slide, modified trichrome-stained concentrate compared to 249 from the formalin/Hemo-De wet mount and 216 from the unconcentrated trichrome stain. The detection rate of the single slide method was comparable to the combined detection rate of the two-slide method. The saline/Hemo-De concentration procedure has the advantage of using nontoxic saline in place of formaldehyde. This new method is more cost-effective because it requires the processing and evaluation of only one slide.