The present study observed the resistance to reinfection with Clonorchis sinensis in various experimental animals including mice, guinea pigs, rabbits, and dogs, as well as rats and hamsters. The resistance rates to reinfection in rats, mice, hamsters, guinea pigs, rabbits, and dogs were 79.7%, 58.0%, -12.6%, 54.8%, 62.6%, and 6.0%, respectively. Worms recovered from reinfected rats and mice were immature, and significantly smaller than those from the primarily infected (P < 0.01), whereas those from other animals were fully matured to adults. These findings indicate that the protective response against reinfection with C. sinensis is prominent in rats and mice, and that they may be a good animal model to investigate the mechanism of resistance to reinfection with C. sinensis.
Rats ; Rabbits ; Praziquantel/therapeutic use ; Mice ; Guinea Pigs ; Dogs ; Cricetinae ; Clonorchis sinensis/immunology/*physiology ; Clonorchiasis/drug therapy/immunology ; Anthelmintics/therapeutic use ; Animals, Laboratory/immunology/*parasitology ; Animals

Sustained-releasing praziquantel (SRP) tablet was designed for single dose treatment regimen of clonorchiasis. A previous pre-clinical study confirmed its sustained-releasing characteristics and a better cure rate than conventional praziquantel (PZQ). In this clinical study, the pharmacokinetics of this SRP tablet were investigated in human volunteers (phase 1; 12 volunteers), and its curative efficacy was examined in clonorchiasis patients (phase 2; 20 volunteers). In the phase 1 clinical study, blood concentrations of both tablets showed wide individual variation. The AUC(last) of SRP was 497.9+/-519.0 ng.hr/ml (mean+/-SD) and PZQ of 628.6+/-695.5 ng.hr/ml, and the AUC(inf) of SRP was 776.0+/-538.5 ng.hr/ml and of PZQ 658.6+/-709.9 ng.hr/ml. C(max) values of SRP and PZQ were 90.7+/-82.2 ng/ml and 214.9+/-251.9 ng/ml, and T(max) values were 3.42+/-1.43 hr and 1.96+/-1.23 hr, respectively. SRP tablets showed similar AUC values, but lower C(max) and longer T(max) values than PZQ. In the phase 2 study, SRP at 30 mg/kg (single dose) achieved a 60% cure rate and a 95.5% egg reduction rate. The cure rate of a single dose SRP was unsatisfactory compared with that of the conventional PZQ dose, but much better than that achieved by a single dose PZQ.
*Praziquantel/adverse effects/pharmacokinetics/therapeutic use ; Parasite Egg Count ; Male ; Humans ; *Delayed-Action Preparations/pharmacokinetics/therapeutic use ; Clonorchis sinensis/*drug effects/isolation & purification ; Clonorchiasis/*drug therapy ; Area Under Curve ; *Anthelmintics/adverse effects/pharmacokinetics/therapeutic use ; Animals ; Adult

We measured changes in sonographic findings of patients with clonorchiasis after a treatment in a highly endemic area. A total of 347 residents showed positive stool results for Clonorchis sinensis eggs in a village in northeastern China, and were treated with praziquantel. Of them, 132 patients underwent abdominal sonography both before and 1 year after treatment, and the changes in sonographic findings of 83 cured subjects were compared. Diffuse dilatation of intrahepatic bile ducts (DDIHD) was found in 82 patients (98.2%) before and 80 (96.4%) after treatment, which was improved in 3, aggravated in 1, and unchanged in 79 patients. Increased periductal echogenicity (IPDE) was observed in 42 patients (50.6%) before and 45 (54.2%) after treatment, which was improved in 5, aggravated in 8, and unchanged in 70 patients. Floating echogenic foci in the gallbladder (FEFGB) was detected in 32 patients (38.6%) before and 17 (20.5%) after treatment, which was improved in 20, aggravated in 5, and unchanged in 58 patients. Improvement of FEFGB only was statistically significantly (P = 0.004). The present results confirm that DDIHD and IPDE persist but FEFGB decreases significantly at 1 year after treatment. In a heavy endemic area, the sonographic finding of FEFGB may suggest active clonorchiasis 1 year after treatment.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Bile Ducts, Intrahepatic/parasitology/ultrasonography ; Child ; China/epidemiology ; Clonorchiasis/complications/*drug therapy/epidemiology/*ultrasonography ; *Endemic Diseases ; Female ; Gallbladder/parasitology/ultrasonography ; Humans ; Male ; Middle Aged ; Praziquantel/*therapeutic use ; Treatment Outcome ; Young Adult

Oriental liver fluke (Clonorchis sinensis) infection was surveyed among residents of Hamyang-gun, Gyeongsangnam-do, Korea during the period of January 2001 to March 2002. Total 1,041 stool samples were collected from residents who visited Public Health Center and its branches in Hamyang-gun and examined using formalin-ether sedimentation method. The overall egg positive rate was 16%, male showing higher positive rate (21%) than female (10%). The age group of 30 to 50 years had the highest egg positive rate of C. sinensis from 20% to 22%. The positive examinees were treated with praziquantel and educated individually to prevent reinfection. Egg positive rate in this area was decreased when compared with results recorded in the past, however, still remained more than 10%. This study suggests that periodic examination, treatment as well as education of residents should be continued and systematized.
Adolescent ; Adult ; Age Factors ; Aged ; Child ; Clonorchiasis/drug therapy/*epidemiology/parasitology ; Feces/parasitology ; Female ; Human ; Korea/epidemiology ; Male ; Middle Aged ; Parasite Egg Count ; Patient Education ; Praziquantel/therapeutic use ; Sex Factors ; Support, Non-U.S. Gov't

A cohort was established for evaluation of cancer risk factors in Sancheong-gun, Gyeongsangnam-do, Korea. As one of the cohort studies, stools of 947 residents (403 males and 544 females, age range: 29-86 years) were screened for Clonorchis sinensis eggs using both Kato-Katz method and formalin-ether sedimentation technique. The overall egg positive rate of C. sinensis was 37.7% and individual EPG (eggs per gram of feces) counts ranged from 24 to 28,800. Eight egg positive residents voluntarily joined a process of collection of the passed worms after praziquantel treatment. A total of 158 worms were recovered from 5 of the 8 treated persons, ranged from 3 to 108 in each individual. The worms were 15-20 mm x 2-3 mm in size, and showed brown-pigmented, red, or white body colors. This is the first collection record of C. sinensis adult worms from humans through anthelmintic treatment and purgation. The adult worms of C. sinensis may be paralyzed by praziquantel and then discharged passively through bile flow in the bile duct and by peristaltic movement of the bowel.
Adult ; Aged ; Aged, 80 and over ; Animals ; Antiplatyhelmintic Agents/*therapeutic use ; Clonorchiasis/*drug therapy/epidemiology/*parasitology ; Clonorchis sinensis/anatomy & histology/*isolation & purification ; Feces/parasitology ; Female ; Humans ; Korea/epidemiology ; Male ; Middle Aged ; Neoplasms/epidemiology ; Parasite Egg Count ; Praziquantel/*therapeutic use ; Risk Factors

No abstract available.
Aged, 80 and over ; Animals ; Anthelmintics/therapeutic use ; Bile Duct Neoplasms/diagnosis/surgery/ultrasonography ; Cholangiopancreatography, Endoscopic Retrograde ; Clonorchiasis/*diagnosis/drug therapy/surgery ; Clonorchis sinensis/isolation & purification ; Common Bile Duct/ultrasonography ; Humans ; Male ; Praziquantel/therapeutic use ; Tomography, X-Ray Computed

Chemotherapy of clonorchiasis with praziquantel (PZQ) is effective but about 15% of treated cases have been reported uncured. The present study investigated correlation of single nucleotide polymorphisms (SNPs) of the cytochrome P450 gene, CYP3A5 and cure of clonorchiasis. A total of 346 egg passing residents were subjected and treated by 3 doses of 25 mg/kg PZQ. Reexamination recognized 33 (9.5%) uncured and 313 cured. Numbers of eggs per gram of feces (EPGs) before treatment were significantly lower in the cured group than in the uncured group (2,011.2+/-3,600.0 vs 4,998.5+/-7,012.0, P<0.001). DNAs of the subjects were screened for SNPs at 7 locations of CYP3A5 using PCR. In the uncured group, the SNP frequencies at g.-20555G>A and g.27526C>T of CYP3A5 were 15.2% and 9.1% while those were 3.8% and 1.0%, respectively, in the cured group. The cure rate was significantly lower in the cases with SNP at g.27526C>T and EPGs> or =1,000. In conclusion, EPGs and SNPs of CYP3A5 are factors which influence cure of clonorchiasis by PZQ therapy. It is strongly suggested to recommend 2-day medication for individuals with high EPGs> or =1,000.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Animals ; Child ; Clonorchiasis/*drug therapy/*genetics/parasitology ; Clonorchis sinensis/isolation & purification/physiology ; Cytochrome P-450 CYP3A/*genetics ; Feces/parasitology ; Female ; Humans ; Male ; Middle Aged ; *Polymorphism, Single Nucleotide ; Praziquantel/*therapeutic use ; Treatment Outcome ; Young Adult

Praziquantel is the drug of choice for clonorchiasis. Since clonorchiasis is endemic in most river basins, praziquantel has been widely used for 30 years in Korea. A 54-year-old Korean woman suffered from hypersensitive reactions, such as nausea, dyspnea, rash, and urticaria after taking the first dose of praziquantel to treat clonorchiasis. She ingested one dose again and the same symptoms appeared, and she was treated at a clinic with anti-histamines. She tried one more dose with anti-histamines but found the same symptoms. Later, she was found to pass eggs of Clonorchis sinensis and medicated with flubendazole. The hypersensitive reaction to praziquantel is rare but occurs. This is the 5th case report in the world.
Animals ; Anthelmintics/*administration & dosage/*adverse effects ; Clonorchiasis/*complications/*drug therapy ; Clonorchis sinensis/isolation & purification ; Drug Hypersensitivity/*diagnosis/drug therapy/pathology ; Feces/parasitology ; Female ; Histamine Antagonists/administration & dosage ; Humans ; Mebendazole/administration & dosage/analogs & derivatives ; Middle Aged ; Praziquantel/*administration & dosage/*adverse effects ; Republic of Korea

The main causes of biliary obstruction are stones and cancers. Fascioliasis is a very rare case which causes biliary obstruction. Fascioliasis is a zoonosis caused by Fasciola hepatica which infects herbivores like sheep and cattle. F. hepatica lives in the biliary system or the liver parenchyma of a host. In Korea, the occurrence of this infection in human is very rare and only few cases have been reported. A 32-year-old male presented with upper abdominal pain and jaundice. His laboratory finding revealed elevated liver transaminases. Abdomen CT scan showed mild left intrahepatic bile duct dilatation. On ERCP, adult F. hepatica worms were found and were thus removed. Concurrently, clonorchiasis was diagnosed by stool exam and serologic enzyme-linked immunosorbent assay test. Clonorchiasis was treated with praziquantel. Herein, we report a case of intrahepatic bile duct dilatation due to F. hepatica infection with concurrent Clonorchis sinensis infestation.
Adult ; Animals ; Anthelmintics/therapeutic use ; Benzimidazoles/therapeutic use ; Bile Ducts, Intrahepatic ; Cholangiopancreatography, Endoscopic Retrograde ; Clonorchiasis/complications/*diagnosis/drug therapy ; Clonorchis sinensis/immunology/isolation & purification ; Enzyme-Linked Immunosorbent Assay ; Fasciola/isolation & purification ; Fascioliasis/complications/*diagnosis/parasitology ; Humans ; Liver/enzymology ; Male ; Praziquantel/therapeutic use ; Tomography, X-Ray Computed ; Transaminases/metabolism