Pulmonary embolism: difficulties in the clinical diagnosis.

Pulmonary embolism is a common disease in the United States, affecting as many as 500,000 persons annually. Unfortunately, underdiagnosis of the disorder is also common, resulting in significant excess morbidity and mortality rates. Factors such as a lack of symptoms or the unavailability of effective testing techniques are not the reasons for pulmonary embolism's underdiagnosis. Instead, the disease is often often overlooked because the symptoms and signs caused by pulmonary embolism are nonspecific and may be confused with a variety of other cardiopulmonary disorders that have similar presentations. In addition to this overlap of symptoms and signs, pulmonary embolism frequently coexists with those diseases it mimics. This article describes the clinical characteristics of pulmonary venous thromboembolism, reviewing the symptoms and signs it typically exhibits, as well as the disease's routine laboratory test and chest radiographic abnormalities. These are contrasted with the clinical features of pneumonia, the disease for which pulmonary embolism is most commonly mistaken. I will show that clinical features can be used to increase suspicion for pulmonary embolism, but that additional diagnostic testing is necessary to definitively diagnose or exclude the condition. Accurate diagnostic tests are available for venous thromboembolism, even in the face of other coexistent cardiopulmonary disorders. As such, it should be possible to significantly reduce the morbidity and mortality rates caused by pulmonary embolism through both heightened clinical awareness and appropriate use of diagnostic testing strategies.