Morbidity of schistosomiasis mansoni in the highlands of Madagascar and comparison of current sonographical classification systems

High burden of Schistosoma mansoni infection in school-aged children in Marolambo District, Madagascar

Background

A school-based survey was undertaken to assess prevalence and infection intensity of schistosomiasis in school-aged children in the Marolambo District of Madagascar.

Methods

School-aged children from six purposively selected schools were tested for Schistosoma haematobium by urine filtration and Schistosoma mansoni using circulating cathodic antigen (CCA) and Kato-Katz stool analysis. The investigators did not address soil-transmitted helminths (STH) in this study.

Results

Of 399 school-aged children screened, 93.7% were infected with S. mansoni based on CCA analysis. Kato-Katz analysis of stool revealed S. mansoni infection in 73.6% (215/ 292). Heavy infections (> 400 eggs per gram) were common (32.1%; 69/ 215), with a mean of 482 eggs per gram of stool. Moderate infection intensities were detected in 31.2% (67/ 215) and light infection intensities in 36.7% (79/ 215) of infected participants. No infection with S. haematobium was detected by urine filtration.

Conclusions

Intestinal schistosomiasis appears a considerable public health issue in this remote area of Madagascar where there is a pressing need for mass drug administration.

Comparison between clinical and ultrasonographic findings in cases of periportal fibrosis in an endemic area for schistosomiasis mansoni in Brazil

INTRODUCTION: Abdominal palpation and ultrasound findings among patients from an endemic area for schistosomiasis in Brazil who had been followed up for 27 years were compared. METHODS: In 2004, 411 patients from Brejo do Espírito Santo, in the State of Bahia, were selected for the present investigation after giving their written informed consent. Based on clinical data, they were divided into three groups: 41 patients with evidence of liver fibrosis in 2004 (Group 1); 102 patients with evidence of liver fibrosis in the past (1976-1989) but not in 2004 (Group 2); and 268 patients without evidence of liver fibrosis at any time during the 27-year follow-up (Group 3). All of the patients underwent abdominal ultrasound in which the examiner did not know the result from the clinical examination. The data were stored in a database. RESULTS: The prevalence of periportal fibrosis on ultrasound was 82.9%, 56.9% and 13.4% in Groups 1, 2 and 3, respectively. In the presence of hard, nodular liver or prominent left lobe and a hard palpable spleen, ultrasound revealed periportal fibrosis in 70.9%. However, periportal fibrosis was diagnosed using ultrasound in 25.4% of the patients in the absence of clinical evidence of liver involvement. Thus, ultrasound diagnosed periportal fibrosis 3.1 times more frequently than clinical examination did. CONCLUSIONS: Although clinical examination is important in evaluating morbidity due to Manson's schistosomiasis in endemic areas, ultrasound is more accurate in diagnosing liver involvement and periportal fibrosis.

[Sonographic evaluation of periportal fibrosis in children living in a Schistosoma mansoni endemic region]

PURPOSE

To assess with ultrasound periportal fibrosis due to chronic Schistosoma mansoni infection in children living in an endemic region. Materials and methods. A total of 441 children underwent two stool examinations and abdominal sonography. Liver echotexture was assessed by two observers and compared to pre-defined image patterns and a fibrosis score was assigned ranging from 0 to 8. Ultrasound features were correlated to age, sex, and parasitologic findings.

RESULTS

Prevalence of Schistosoma mansoni infestation was 63%. Two cases of advanced fibrosis (E pattern or fibrosis score of 6) were observed. Fibrosis correlated with age. No correlation existed between fibrosis and intensity of egg-output. A correlation between the two examinors was noted in 84% of examinations with a kappa coefficient of 0.7.

CONCLUSION

Although severe periportal fibrosis is a rare finding in this endemic region, follow-up sonography must be performed because it is the only non invasive and reliable tool for detection of periportal fibrosis.