Evaluation of Cellotape Anal Swabs in the Diagnosis of enterobiasis

요충층에 있어서 항문주위 도말법의 검토

Enterobiasis is common helminthic infections found in man. But control of this disease is still troublesome because of its difficulty in the d diagnosis and prevention of infection. Considering the difficulty of accurate diagnosis of pinworm infection, which is very common and somewhat pathogenic, reevaluation of cellotape anal swab method for the diagnosis of enterobiasis was performed. A total of 147 children ranging the ages of 1-12 years in 3 orphanages in the suburbs of Seoul, Korea was subjected for this study. Repeated cellotape anal swabs were carried out against 70 children, 7 times for 3 days interval, in the morning 6am. Finally 10 mg/kg body weight pyrantel pamoates were given to all children including egg negative cases and whole stools of 3 following successive days were collected for the confirmation of residual worm ourden at the time of treatment. Cellotape anal swabs were also performed to another 77 children at 6am, 3pm, 9pm, twice for 3 days interval. The resultant findings were summarized as follows; 1) While the each time average detection rate of Enterobius egg was 28.8% in this study group, the accumulative detection rate up to 7th examination was 62.8%. The accumulative detection rate rose continuously up to 6th examination. 2) After administration of pyrantel pamoate 10 mg/kg body weight, final infection rate was increased to 72.9% by adding worm positive cases who didn't show any evidence of infection in the cellotape anal swabs. 3) Although pinworms were detected in 35 among 70 children treated, 7 cases (20%) of them were egg negative cases in 7 consecutive cellotape anal swabs. 4) Pinworms were expelleded in 14 (87.5%) among 16 children whose swab result was positive in the last examination which was done concurrently with drug administration. 5) Estimated infection rate calculated by best asymptotically normal estimate of Neuman from Moriya's modification revealed 71.5% similar to 72.9% of present results. 6) The result of anal swab performed at 6am was higher than that of 3pm or 8pm. In conclusion, cellotape anal swab method for Enterobius vermicularis infection was considered as method having relatively high positive accuracy. However to gain the reliable infection rate, at least 6 examination is required in the group with 25-30% infection rate by single swab. Moriya's modification of Neuman could be used efficiently in the mass control of this diease for the estimation of true infection rate of E. vermicularis in the sampled population.