Grading the Severity of a Clonorchiasis Based on the Number of Eggs per Gram of Feces (EPG)

 

Common methods for counting eggs in the feces:

(1) direct smear

(2) Kato-Katz smear

 

number of eggs per gram of feces using direct smear =

= (number of eggs counted) * (1000 mg) / (mg of stool used to make the smear)

 

number of eggs per gram of feces by direct smear =

= (3.76 * (number of EPG by Kato-Katz method)) - 2,479

 

number of eggs per gram by Kato-Katz method =

= (0.266 * (number of EPG by direct smear)) + 659.4

 

Number of Eggs per Gram Feces by Kato-Katz Method	Infection Intensity
0	negative
1 to 500	light
501 to 1,999	moderate
>= 2,000	heavy