Extract
A heart disease caused by a protozoan affecting millions of people in South America was discovered 100 years ago by Carlos Chagas (see Box 1). It is the leading cause of heart failure in endemic areas, while prevention and treatment still have a long way to go. J. Taylor delivers the story from Reinaldo B. Bestetti, MD, PhD, FESC, Head of Cardiology and Cardiovascular Surgery, Hospital de Base, Faculdade de Medicina de São José do Rio Preto, Brazil.
Chagas' disease (American Trypanosomiasis) is a tropical disease caused by the protozoan Trypanosoma cruzi. In natural conditions, infection with T. cruzi occurs in early infancy. About 15 days after infection, fever, lymphadenopathy, hepato-splenomegaly, and subcutaneous oedema ensues. This acute stage lasts about a 1 month, and then the patients appear to fully recover.
After about 2 months, a positive serology appears, but no evidence of organ disease exists. However, about 20 years later, some 30% of infected patients develop chronic Chagas' heart disease and 10% develop gastrointestinal (G-I) tract diseases (megaesophagus and megacolon). The remaining 60% are asymptomatic but have positive serology. ‘This unusual clinical course of Chagas’ is still poorly understood, and the pathogenesis is undetermined in spite of numerous studies', says Dr Bestetti.
