Two-year impact of praziquantel treatment for Schistosoma japonicum infection in China: re-infection, subclinical disease and fibrosis marker measurements

Abstract

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. juponicum infection before treatment were 28% and 192 eggs per gram faeces (epg), respectively. Two years after cure, 22% of the cohort were reinfected, but with a lighter intensity (67 epg). Sixty-four subjects (37%) showed significant improvement in ultrasound parenchyma images after treatment and 5 1 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 I. Two years post-treatment a dilated portal vein became less frequent, but the decline was not significant (16% vs 1 1 %, P > 0.05). The serum levels of laminin and collagen IV associated with reinfection 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. juponicum 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.

Serum hyaluronan and collagen IV as non-invasive markers of liver fibrosis in patients from an endemic area for schistosomiasis mansoni: a field-based study in Brazil

“…In Tanzania, a correlation between serum C-IV and clinical and sonographic signs of hepatosplenic schistosomiasis was observed, but it did not have enough sensitivity to be useful as a screening tool for fibrosis (Kardorff et al 1999). Two independent groups in China found C-IV to be higher in subjects infected with Schistosoma japonicum (Guangjin et al 2002) and to correlate with re-infection after treatment of schistosomiasis japonica with praziquantel (Li et al 2000). Wyszomirska et al (2005Wyszomirska et al ( , 2006 investigated C-IV for the detection of schistosomiasis-related liver fibrosis in a tertiary care hospital in Brazil.…”

Assessment of the age-specific disability weight of chronic schistosomiasis japonica

“…Hepatic fibrosis, especially grade II and grade III, is a sound marker for chronic schistosomiasis japonica. 36,37 In this study, seropositive individuals with a history of recent contact with cercariae-infested water were examined by ultrasonography, and those with typical pathological features were defined as cases with chronic schistosomiasis. Cases concurrently diagnosed with other diseases (for example, hepatitis B and C) were excluded to avoid confounding when estimating the disability weight attributable to chronic schistosomiasis japonica.…”

Liver morbidity due to Schistosoma mekongi in Cambodia after seven rounds of mass drug administration

“…Thirdly, a 2-year cohort study of liver morbidity due to S. japonicum showed that after a single treatment with praziquantel, sub-clinical liver morbidity was significantly reduced (Li et al, 2000), but even after 5 years followup the resolution was not complete (Li et al, 2002). It was concluded that pathological changes around the portal tree might regress to a large degree but that 'network pattern' abnormalities do not normally resolve (Richter, 2000).…”