Chagas heart disease showing severe myocarditis. (Left panel) Light micrograph of the myocardium in the acute phase: intense parasitism of muscle fibers by amastigote forms of Trypanosoma cruzi has led to the formation of pseudocysts (arrow). (Right panel) High-power view more clearly shows T. cruzi pseudocysts.
Courtesy of João Samuel Meira Oliveira, MD and Harriet Provine.