Color Doppler ultrasound satisfactorily detects sacroiliitis in patients with IBP
The diagnostic properties of color Doppler ultrasound (CDUS) for the detection of sacroiliitis is acceptable, reports a new study, adding that CDUS may be useful in patients with inflammatory back pain (IBP).
The study included consecutive patients with IBP and suspected axial spondyloarthritis (SpA), but without a definitive diagnosis. For the control group, consecutive patients with defined SpA and axial involvement were recruited.
All patients underwent clinical evaluation, magnetic resonance imaging (MRI) and CDUS of sacroiliac joint (SIJ) within the same week. Using MRI as the gold standard, the authors calculated sensitivity, specificity, positive (PPV) and negative predictive values (NPV) for the diagnosis of sacroiliitis by CDUS.
In 99 patients (mean age, 39.8 years; 61.6 percent men), 198 SIJs were evaluated (36 with previous SpA). Median disease duration was 24 months (interquartile range, 12–84).
At the patient level, CDUS demonstrated a sensitivity of 63 percent (95 percent CI, 48.7–75.7 percent) and a specificity of 89 percent (76–96 percent), with PPV of 87.2 percent (72.6–95.7 percent) and NPV of 66.7 percent (53.3–78.3 percent). At joint level, CDUS showed a sensitivity of 60 percent (49–70 percent) and a specificity of 93 percent (88–98 percent), with PPV of 83 percent (78–95 percent) and NPV of 43 percent (33–56 percent).
For the diagnosis of axial SpA, CDUS had a sensitivity of 54 percent (36.6–71.2 percent), specificity of 82 percent (63.1–93.9 percent), with PPV of 79 percent (57.8–92.9 percent) and NPV of 59 percent (42.1–74.4 percent).