I. Epidemiology
II. Symptoms and Signs
III. Diagnostic Investigations
IV. Management
GLOSSARY
arrhythmia general term for an irregularity or rapidity of the
heartbeat, an abnormal heart rhythm. cardiomyopathy heart muscle disease. ejection fraction the fraction of blood ejected from the heart
into the arteries, normally this ranges from 60 to 75%; a low
ejection fraction is less than 40%; often used as a marker of
ventricular contractility. hypokinesis decreased myocardial contraction usually caused by
damage and weakness of the heart muscle due to coronary
artery disease and cardiomyopathies. myocardium the heart muscle.

• I. EPIDEMIOLOGY
  The protozoan Trypanosoma cruzi causes Chagas disease, which affects more than 30 million individuals, with approximately 100 million at risk in Latin America. Figure 1 shows the distribution of Chagas disease in the Americas. This disease is prevalent only in Central and South America, particularly in Argentina, Chile, Brazil, and Bolivia. It also occurs in the southern United States, however, where more than 90,000 Latin Americans are believed to be infected. The risk of transmission in the United States is mainly by blood transfusion by this immigrant population.
• II. SYMPTOMS AND SIGNS A. Acute Phase
  The bite of the bug around the eyes allows the trypanosomes to gain entry through the conjunctiva. This often results in one-sided swelling around the eye (periorbital edema) and swelling of the eyelid (Romana sign). If the entry is through the skin, a lesion called a chagoma appears. The initial lesion may go unrecognized, however, and no symptoms may appear until after more than 15 years when symptoms of chronic disease emerge. In about 10% of infected individuals acute symptoms such as muscle aches and pains, fever, sweating, and enlargement of the liver and spleen occur. If the parasitic infection involves the cardiac muscle, an acute myocarditis and heart failure may supervene causing death. Lesions may spread to involve the endocardium and stimulate the flowing blood to form a clot that may embolize. The pericardium may be involved causing pericardial effusions. Young children become more seriously ill than young adults, and in more than 10% the acute disease is fatal. Many patients recover, however, and symptoms disappear over 1–2 years. More than 40% of infected patients after a relatively symptom-free interval of several years reveal signs and symptoms of chronic Chagas disease.
• III. DIAGNOSTIC INVESTIGATIONS
  A. Chest X-ray
• IV. MANAGEMENT
  A. Prevention
• BIBLIOGRAPHY
  Apt, W., Aguilera, X., Arribada, A. et al. Treatment of chronic Chagas disease with itraconazole and allopurinol. Am. J. Trop. Med. Hyg., 59:133, 1998.