To the Editor: Blood-culture–negative endocarditis has been described in about 12 percent of children with endocarditis.1 Because of recent diagnostic advances, some of the pathogens responsible for these cases have been identified. A 13-year-old girl from Senegal was referred to our center for surgical treatment of rheumatic heart disease, which had been diagnosed when she was 8 years of age. She lived in a large city in a stable environment, did not abuse drugs, and had no close contact with cats. At admission, she was in good general condition and had no signs of intercurrent infection, fever, or lymphadenopathy. The . . .