RESUMEN
BACKGROUND: Although human parasitic infestations have decreased generally in Korea, Clonorchis sinensis, Paragonimus westermani, Cysticercus and Sparganum are still a serious concern due to their relatively high prevalence and severe complications. A definitive diagnosis, however cumbersome and occasionally invasive, is required in order to detect adult worms, eggs, or cysts. The parasite-specific IgG antibody (PSA) test using the ELISA method has been recently developed to diagnose and monitor the infestations of those four parasites. We analysed PSA positive patients for Clonorchis sinensis, Paragonimus westermani, Cysticercus and Sparganum. METHODS: The serum samples referred to the Neodin Medical Institute for PSA were tested by the ELISA method using crude extracts of C. sinensis, P. westermani, Sparganum and cystic fluid of Cysticercus. The PSA results during the 7-month period from January to July 2001 were retrospectively analysed. The medical records of the patients at Asan Medical Center (AMC) with positive PSA were reviewed with stool examinations for parasites, skin tests for C. sinensis and P. west-ermani, radiological findings and antiparasitic management. RESULTS: A total of 865 specimens were tested for PSA and 84 samples (9.7%) of 76 patients were positive; C. sinensis, Cysticercus, Sparganum, and P. westermani were positive in 26 patients (3.0%), 26 (3.0%), 14 (1.6%) and 10 (1.2%), respectively. 26 specimens from 18 AMC patients were positive for one or more PSA; 6 Cysticercus. 4 C. sinensis, 5 Sparganum and 3 P. westermani. All PSA-positive cases for Cysticercus, C. sinensis and P. westermani were compatible with the clinical diagnosis; however, it was difficult to elucidate in the clinical correlation of 3 out of 5 Sparganum-positive cases. CONCLUSION: Cysticercus, C. sinensis and P. westermani are currently prevalent in Korea. Positive PSA ELISA tests for Cysticercus, C. sinensis and P. westermani are reliable indicators in diagnosing present infestations among the clinically suspected patients.