Pre- and posttreatment serodiagnosis for paragonimiasis

An undebatable diagnosis of paragonimiasis depends on the recovery of eggs from sputum or stools. Recovery of eggs, however, is not easy and often very difficult in cases of infection of low intensity, of latent clinical symptomatology, of previous but insufficient chemotherapy and in cases of P. miyazakii infection. A considerable amount of work on immunological diagnosis has been done, and it is well known that positive serological tests for paragonimiasis are closely connected with the survival of worms in the patient. In follow-up studies after treatment, the antibody titers of the complement fixation test in cured patients showed a tendency of decrease immediately after treatment and finally became negative during a period of 1 to 12 months. Haemagglutination and immunofluorescence tests also showed a tendency of decreasing titers. Results became negative within 18 months after treatment. The precipitin bands of Ouchterlony and immunoelectrophoresis became negative during a period of 3 to 24 months after successful treatment. From the above mentioned results it is evident that serological tests are very useful parameters for the assessment of cure.