Preliminary studies investigating the occurrence of Biomphalaria cousini in Brazil

Clinical-epidemiological and laboratory profiles of severe Schistosomiasis mansoni infections at a university hospital

OBJECTIVE

Schistosomiasis remains a public health problem. This was a descriptive and retrospective study of 42 patients with a severe form of schistosomiasis who were admitted to the outpatient clinic of the Faculdade de Medicina da Universidade de São Paulo, São Paulo, in São Paulo, Brazil.

METHODS

A data collection questionnaire was designed from the patient charts, and the following variables were evaluated: age, sex, place of birth, occupation, signs and symptoms of schistosomiasis, data from laboratory and imaging examinations, data regarding treatment outcomes, and the existence of comorbidities. Statistical analysis was carried out using Statistical Package for the Social Sciences 15.0 and Microsoft Excel 2003 software. The significance levels of the tests were fixed, accepting 5% type 1 error (α=0.05). Since this was a retrospective observational study, not all data were available for analysis.

RESULTS

The mean age of the patients was 48.24 years; 57.1% were male. Statistically significant associations were observed between splenomegaly and thrombocytopenia (p=0.004) and between splenomegaly and leukopenia (p=0.046); however, only 4.5% of the patients had esophageal hemorrhage. Some patients received a specific treatment; of those, 42% took praziquantel, and 35.4% took oxamniquine. Nonspecific drug therapy was given as follows: 65% received propranolol, 90% omeprazole, and 43.6% aluminum hydroxide. The other treatments were as follows: 92.9% of patients underwent endoscopic treatment, 85% received sclerotherapy, and 62.5% used elastic bandages.

CONCLUSION

This preliminary study presents a multidisciplinary outpatient follow-up associated with endoscopic and drug treatments that may be effective at preventing bleeding.

Development of species-specific primers for identification of Biomphalaria arabica, the intermediate host of Schistosoma mansoni in Saudi Arabia

Schistosoma mansoni is mediated through the intermediate host Biomphalaria arabica which lives in Saudi Arabia. Molecular characterization and identification of this intermediate host are important for epidemiological studies of schistosomiasis. The present work aimed to determine the molecular variations among the populations of B. arabica found in Southern part of Saudi Arabia, and to develop species-specific primers for identification of these snails as a first step in the development of multiplex PCR for simultaneously identifying the snails and diagnosing its infections in a single step. Five populations of Saudi B. arabica snails were collected from freshwater bodies. Three populations were collected from Asser and two populations were collected from AL-Baha. Genomic DNA was extracted from snails and was amplified using five different RAPD-PCR primers. The banding patterns of amplified materials by primers P1 and P5 were identical in all populations. However, the rest primers displayed intra-specific differences among populations with variable degrees. Largest sizes of RAPD-PCR products were cloned into TA cloning vector as a preparatory step for DNA sequence analysis. After sequencing, similarity searches of obtained DNA sequences revealed that there are no similar sequences submitted to genebank data bases and its associated banks. The results obtained will be helpful in the development of simultaneous identification of B. arabica snails and diagnosis of S. mansoni infection within it in a single step by an implementation of multiplex PCR.