Abdominal pain with free peritoneal fluid detected by ultrasonography as a presenting manifestation of acute rheumatic fever.

The clinical and laboratory data for an 8 year old girl with abdominal pain as a presenting manifestation of acute rheumatic fever are reported. An abdominal investigation with ultrasonography carried out at the same time showed free peritoneal fluid. These findings support the proposal that the abdominal pain classically described in acute rheumatic fever is one of the manifestations of the inflammatory process. It is suggested that in patients with abdominal pain, fever, and increased erythrocyte sedimentation rate in whom the diagnosis is not clear, an abdominal investigation with ultrasonography could be helpful in establishing the correct diagnosis.