Evaluation of potassium hydroxide for wet mount preparation of stool for detection of intestinal parasites.
Potassium hydroxide (KOH) is widely used in the wet mount preparation of various clinical specimens for demonstration of fungi and fungal elements. In the present study we have evaluated the use of KOH in the wet mount preparation of fresh stool specimens for the demonstration of intestinal parasites. The KOH wet mount of stool was compared with saline, iodine and lacto-phenol cotton blue (LPCB) wet mount preparations of stool. A total of 855 fresh stool specimens were examined in the study of which 419 specimens were found to be positive for either trophozoites, cysts, ova or larvae of different parasites by all these methods. A total of 309 stool specimens were positive by KOH preparation of stool, while 289, 245 and 208 stool specimens were positive by LPCB, iodine and saline preparations respectively. The KOH was found to be effective in lysing the faecal debris, faecal mass and other artifacts without affecting many of the parasitic ova, cysts and larvae in the stool smears. The parasitic ova, cysts and larvae were impacted by the use of 10% KOH and could be easily visualized, detected and identified against a clear background in the stool smear I hr after preparation of KOH wet mount. From these findings we recommend the routine use of KOH wet mount of stool for demonstration of intestinal parasites in a parasitology laboratory.
Parija
S C
SC
Department of Microbiology, Jawaharlal Institute of Postgraduate Medical Education & Research, 605 006, Pondicherry, India. parijasc@vsnl.com
Shivaprakash
M R
MR
D000818:Animals; D005243:Feces / Q000469:parasitology*; D006801:Humans; D006878:Hydroxides; D007411:Intestinal Diseases, Parasitic / Q000175:diagnosis* / Q000469:parasitology; D017680:Potassium Compounds; D013997:Time Factors
D006878:Hydroxides; D017680:Potassium Compounds; C029943:potassium hydroxide