Fever in acute pulmonary embolism

Although fever has been reported in several case series of acute pulmonary embolism (PE), the extent to which fever may be caused by PE, and not associated disease, has not been adequately sorted out. Clarification of the frequency and severity of fever in acute PE may assist in achieving an accurate clinical impression, and perhaps avoid an inadvertent exclusion of the diagnosis.

The purpose of this investigation is to evaluate the extent to which fever is caused by acute PE.

Patients participated in the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED). Temperature was evaluated among patients with angiographically proven PE. A determination of whether other causes of fever were present was based on a retrospective analysis of discharge summaries, PIOPED summaries, and a computerized list of all discharge diagnoses.

Among patients with PE and no other source of fever, fever was present in 43 of 311 patients (14%). Fever in patients with pulmonary hemorrhage or infarction was not more frequent than among those with no pulmonary hemorrhage or infarction, 39 of 267 patients (15%) vs 4 of 44 patients (9%; not significant). Clinical evidence of deep venous thrombosis was often present in patients with PE and otherwise unexplained fever.

Low-grade fever is not uncommon in PE, and high fever, although rare, may occur. Fever need not be accompanied by pulmonary hemorrhage or infarction.