The times between the onset of symptoms and uFPA testing were significantly (p = 0.025) shorter in patients with PE (13 h, range 6 to 24 h) than those without PE (27.6 h, range 8 to 72 h).
PE was diagnosed by PA in four patients and by the V/Q scan criteria in three patients. PE was excluded by a normal V/Q scan in 16 patients and by negative PA in six patients. Individual patients results are presented in Figure 1. birth control yasmin
The uFPA concentration was significantly higher in the patients with PE than in those without PE (41.1 ±2.6 ng/mg vs 4.8±2.5 ng/mg, p<0.0001). The threshold value of 9.8 ng/mg was set by adding two geometric SDs to the geometric mean value of the subjects in whom PE was excluded. The sensitivity and specificity of the uFPA test are 100 percent and 82 percent, respectively. In the combination approach, PE was excluded if at least one of the two tests was negative. The true-negative rate was calculated for V/Q scan (72 percent), uFPA test (82 percent), and a combination of the two tests (95 percent). Five patients without PE had abnormal V/Q scan results but negative uFPA tests (Fig 1). One of these patients had pneumonia and the other four had exacerbation of chronic obstructive pulmonary disease. Four patients without PE had abnormal uFPA test results. One of these patients had active rheumatoid arthritis, two had an underlying malignancy, and one carried a diagnosis of adult respiratory distress syndrome, conditions all known to increase uFPA.
Figure 1. The uFPA concentration and V/Q scan results in 29 patients with suspected PE. The filled circles indicate patients with PE and the open circles indicate the patients in whom PE was excluded. The dotted line indicates a threshold level of 9.8 ng/ml. Patients are grouped into vertical columns in accordance with V/Q scan result (HP = “high probability of PE”; MP = “moderate probability of PE”; LP = “low probability of PE”; and NL = normal perfusion part of V/Q lung scan).