STUDIES ON SCHISTOSOMIASIS JAPONICA WITH PARTICULAR REFERENCE TO RECTAL BIOPSY

For the clinical evaluation of rectal biopsy, 217 patients with a variety of complaints, who were treated in the Koma-Kyoritsu Hospital during 1967 to 1973, were tested by rectal biopsy, the threshold value of skin test, the COP test and feces examination under the suspicion of chronic schistosomiasis japonica.1) The detection rate of fresh eggs by rectal biopsy was markedly higher in the younger age-group below 30 years. This rate became also significantly higher in parallel with the increase of egg-number in the rectal specimen.2) The incidence of hemorrhoids was significantly higher in the group with old eggs only than that containing fresh eggs.3) After the treatment with Niridazole, the eggs detected by rectal biopsy decreased in number and they were degenerated or destroyed as compared with the pretreatment status.4) Histological examination of the stained specimen obtained by rectal biopsy showed such reaction as eosinophilia of slight degree or edema around the fresh eggs, suggesting an antigenicity of the fresh eggs. However, it was of less importance from the diagnostic point of view, comparing with the press examination of the raw material, because of difficulty to discover the egg and to observe it au naturel.5) In accordance with the increase of the threshold diluting grade of positive skin test, the number of the egg became larger, moreover, the incidence of fresh eggs became higher by rectal biopsy, that is, the number and quality of the egg had a correlation with the threshold value of skin test.6) Even in the egg-negative cases in feces, the possibility of finding the egg was 56% by rectal biopsy. The incidence of the case containing fresh eggs in the biopsy was significantly higher in the egg-positive cases than the egg-negative ones in feces.7) The incidence of relatively fresh eggs in rectal biopsy was significantly higher in the COP-positive group in comparison with the COP-negative group.8) Though the technic was rather difficult, more eggs were found statistically in the posterior wall of the rectum than in the anterior. However, even though in small number, the probability of finding the egg was larger from the anterior wall than the posterior in woman. Thus, rectal biopsy was of great value in the diagnosis and treatment of the disease in Japan.