Lung ultrasound in the diagnosis and follow-up of community-acquired pneumonia: a prospective, multicenter, diagnostic accuracy study.
BACKGROUND
The aim of this prospective, multicenter study was to define the accuracy of lung ultrasound (LUS) in the diagnosis of community-acquired pneumonia (CAP).


METHODS
Three hundred sixty-two patients with suspected CAP were enrolled in 14 European centers. At baseline, history, clinical examination, laboratory testing, and LUS were performed as well as the reference test, which was a radiograph in two planes or a low-dose CT scan in case of inconclusive or negative radiographic but positive LUS findings. In patients with CAP, follow-up between days 5 and 8 and 13 and 16 was scheduled.


RESULTS
CAP was confirmed in 229 patients (63.3%). LUS revealed a sensitivity of 93.4% (95% CI, 89.2%-96.3%), specificity of 97.7% (95% CI, 93.4%-99.6%), and likelihood ratios (LRs) of 40.5 (95% CI, 13.2-123.9) for positive and 0.07 (95% CI, 0.04-0.11) for negative results. A combination of auscultation and LUS increased the positive LR to 42.9 (95% CI, 10.8-170.0) and decreased the negative LR to 0.04 (95% CI, 0.02-0.09). We found 97.6% (205 of 211) of patients with CAP showed breath-dependent motion of infiltrates, 86.7% (183 of 211) an air bronchogram, 76.5% (156 of 204) blurred margins, and 54.4% (105 of 193) a basal pleural effusion. During follow-up, median C-reactive protein levels decreased from 137 mg/dL to 6.3 mg/dL at days 13 to 16 as did signs of CAP; median area of lesions decreased from 15.3 cm2 to 0.2 cm2 and pleural effusion from 50 mL to 0 mL.


CONCLUSIONS
LUS is a noninvasive, usually available tool used for high-accuracy diagnosis of CAP. This is especially important if radiography is not available or applicable. About 8% of pneumonic lesions are not detectable by LUS; therefore, an inconspicuous LUS does not exclude pneumonia.
Department of Internal Medicine, Pneumology and Allergology, Jena, Germany. Electronic address: angelika.reissig@med.uni-jena.de.
Angelika
A
Reissig
Emergency Department, Latisana General Hospital, Latisana, Italy.
Roberto
R
Copetti
Medical Practice, Rankweil, Austria.
Gebhard
G
Mathis
Department of Neurology, Helios Clinic, Erfurt, Germany.
Christine
C
Mempel
Department of Internal Medicine, Helfenstein Clinic, Geislingen, Germany.
Andreas
A
Schuler
Department of Internal Medicine, Hospital Graz West, Graz, Austria.
Peter
P
Zechner
Clinic of Pneumology, University of Milan, IRCCS Fondazione Policlinico, Italy.
Stefano
S
Aliberti
Institute of Diagnostic and Interventional Radiology, Friedrich-Schiller-University, Jena, Germany.
Rotraud
R
Neumann
Department of Internal Medicine, Pneumology and Allergology, Jena, Germany.
Claus
C
Kroegel
Institute of Medical Statistics, Information Sciences and Documentation, Friedrich-Schiller-University, Jena, Germany.
Heike
H
Hoyer
D017714:Community-Acquired Infections / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D005500:Follow-Up Studies; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging*; D011014:Pneumonia / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D012372:ROC Curve; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography