The Kato method
1. Purpose
The kit of reagents is intended for detection in feces of helminths and their eggs in clinical diagnostic laboratories.
The kit is designed to analyze 500 samples.
2. Characteristics of the set
2.1. Principle of the method
Eggs of helminths are found in a thick smear of feces enlightened with glycerin and tinted with malachite green.
2.2. Kit contents:
- Reagent Kato - 1 bottle (50 ml).
- Cellophane coverslips - 500 pcs.
- Cork made of silicone rubber - 1 pc.
6. Analyzed samples
Cal. Examination of the feces no later than 8-12 hours after its excretion, and before that his
should be stored at a temperature of 3-5 ° C. Collect the stool in a clean, dry, wide-brushed glass or plastic dish with a lid.
7. Conducting the analysis
7.1. Preparation for analysis
7.1.1. Kato's Reagent
Ready to use.
After opening the vial, the reagent can be stored at room temperature (18-25) C in a tightly closed vial during the shelf life of the kit.
7.1.2. Treatment of cellophane cover plates with Kato's reagent
The cellophane coverslips in the amount necessary for analysis should be placed in the Kato reagent so that they adhere to each other and stand for 24 hours (10 ml of Kato's reagent per 100 plates).
The finished plates are stored in a Kato reagent, at room temperature in a tightly closed container for the shelf life of the kit.
7.2. Carrying out the analysis
A piece of feces (30-50) mg (the size of a pea), without the addition of water or any other liquid, put on a glass slide and rub it with an individual stick (glass, wooden).
Feces cover with cellophane cover plate, treated with Kato reagent and rub with a plug of silicone rubber until a thin, uniform, transparent layer is obtained.
Feces should be spread on the slide within the cellophane cover slab, and not squeezed out from under it.
The smear should be left for clarification at room temperature for 1 hour or in a thermostat at 40 ° C for 20-30 minutes, after which it is examined under a microscope. In the hot season, to avoid overdrying, the smear is microscopized after 30-40 minutes. In some cases, to avoid excessive drying of the preparation, a wet sponge should be placed on the cellophane cover plate of the prepared preparation.
Microscopy of the smear when magnified: a × 8 or × 10 lens, an eyepiece × 7 or × 10 (to clarify the morphological structure of helminth eggs, the × 40 lens)
8. Evaluation of results
Allows you to view 20-30 times more feces than in the native smear.
Calculate the detected helminth eggs in the entire smear, taking into account their species affiliation. The method reveals infection with ascarids, whipworms, trematodes, tienides and other species, sometimes hookworms and a dwarf chain.
9. Conditions of storage and operation of the kit
The kit should be stored in the manufacturer's packaging at room temperature (18-25) ° C for the entire shelf life.
Shelf life - 2 years.
Kato's reagent after opening the vial can be stored at room temperature in a tightly closed vial during the shelf life of the kit.
Cellophane coverslips can be stored at room temperature during the shelf life of the kit.
