Kato-Katz technique Advantages

155 Pages·2011·9.3 MB·English

by  Prof. Cringoli

Laura Rinaldi and Giuseppe Cringoli
Dept. Pathology and Animal Health, University of Naples Federico II, Naples, Italy
Parasitological Diagnosis
for STH and other parasites
Copromicroscopic techniques
COPROMICROSCOPIC TECHNIQUES
AND PARASITIC ELEMENTS DETECTABLE
Techniques Parasitic elements
Eggs Oocysts Cysts Larvae
Direct Smear O O O O
Simple Flotation in tube O O O
Flotation in centrifuge (Wisconsin) O
McMaster O O
Mes method O
Sedimentation O
Baermann O
Kato Katz O O O
Ether/ethyl acetate concentration O O O
FLOTAC O O O O
Quantitative techniques = O Qualitative techniques = O
Helminths -
Protozoa
COPROLOGICAL
examination
broncopolmonari
Gastro-intestinal tract - Liver, lungs
Sensu stricto
EGGS
LARVAE
OOCYSTS
CYSTS
Ab DNA
Sensu lato
Helminthsand protozoa which inhabitthe GI tract and lungs of the hosts eliminate their
eggs/larvae with the faecesof hosts
STH
Ascaris lumbricoides Trichuris trichiura
Ancylostoma duodenale and Necator americanus
Faecal Egg Count (FEC) techniques are considered relatively straightforward and
protocols such as
the Kato-Katz technique and the ether-based concentration method in the human
field have been available for many years.
Disadvantages
Advantages
Kato-Katz technique
-Small amount of feces exam.
- Simplicity and low cost
(usually 41.7 mg) and thus low
analytic sensitivity (24 EPG)
- Fresh samples
Low sensitivity and accuracy
Ether-based
Disadvantages
Advantages
concentration
- Eggs can be broken or altered
- Stool samples preserved
- Reference laboratory
- Diagnosis of both
- Qualitative
helminths and protozoa
Multivalent techniques
characterized by high
sensitivity, specificity, accuracy