Two-year impact of praziquantel treatment for Schistosoma japonicum infection in China: re-infection, subclinical disease and fibrosis marker measurements.
We studied a community cohort of 193 individuals exposed to endemic Schistosoma japonicum infection in the Dongting Lake region of China to assess subclinical morbidity and the 2-year benefit of curative therapy (praziquantel) administered in 1996. Prevalence and intensity of S. japonicum infection before treatment were 28% and 192 eggs per gram faeces (epg), respectively. Two years after cure, 22% of the cohort were re-infected, but with a lighter intensity (67 epg). Sixty-four subjects (37%) showed significant improvement in ultrasound parenchyma images after treatment and 51 subjects (54%) showed significant improvement of periportal fibrosis. Left-lobe enlargement also reversed (P < 0.05) and splenomegaly reversed in 6 of 8 cases and developed in only 1. Two years post-treatment a dilated portal vein became less frequent, but the decline was not significant (16% vs 11%, P < 0.05). The serum levels of laminin and collagen IV associated with re-infection and intensity and hyaluronic acid levels correlated with ultrasound findings (P < 0.01). Overall, treatment induced a marked decrease in subclinical hepatosplenic morbidity attributable to S. japonicum although low-intensity re-infection after treatment remained relatively frequent. Stratified analysis and logistic models evaluated potential confounding factors for assessment of treatment effects on hepatic fibrosis. S. japonicum infection and moderate-heavy alcohol intake interacted: improvement in parenchymal morbidity was impeded among drinkers (P < 0.05). Chemotherapy focused on at-risk residents controls prevalent subclinical hepatic fibrosis but re-infection indicates the need for complementary control strategies.
Li
Y S
YS
Australian Centre for International and Tropical Health and Nutrition, Queensland Institute of Medical Research, Herston, Brisbane, Australia. yueshenL@qimr.edu.au
Sleigh
A C
AC
Ross
A G
AG
Li
Y
Y
Williams
G M
GM
Tanner
M
M
McManus
D P
DP
D000293:Adolescent; D000328:Adult; D000368:Aged; D000871:Anthelmintics / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D015331:Cohort Studies; D005260:Female; D005355:Fibrosis; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011223:Praziquantel / Q000627:therapeutic use*; D015995:Prevalence; D012008:Recurrence; D012554:Schistosomiasis japonica / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000453:epidemiology; D014463:Ultrasonography
D000871:Anthelmintics; D011223:Praziquantel