Clinical utility of bedside Contrast-Enhanced Ultrasound (CEUS) in the diagnosis of pneumonia in elderly patients: Comparison with clinical, -radiological and ultrasound diagnosis.

Aims: to measure the clinical impact of contrast-enhanced ultrasound (CEUS) in the diagnosis of -community-acquired pneumonia (CAP), compared to clinical, radiological and ultrasound diagnosis.
Methods: 84 patients (47/37 males/females, mean age:78,57±11,7 Y) with clinical suspicion of pneumonia and with ultrasound findings of peripheral lung lesions, were investigated with CEUS for a better characterization. Final diagnosis of 65 cap was obtained with complete disappearance of symptoms and pulmonary nodule(s); 19 neoplasms: 16 patients performed histologically with bronchoscopy; 3 refused (non-invasive diagnosis with basal CT-scan and positron emission tomography (PET) with fluorodeoxyglucose (FDG)). Sensitivity, specificity, overall diagnostic accuracy (ODA) (and corresponding AUROC) of clinical-data (CD), chest X-ray(CXR), Lung-ultrasound(LUS), CEUS were calculated with SPSS 26.0 software.
Results: Final diagnosis: 65 CAP, and 19 chest cancers. 9/65 (13%) patients died, of these 7/9 with older age and heart disease as comorbidity. CD: True-Positive (TP):23, True-negative (TN): 17; False-Positive (FP):2; False-negative (FN):42 (sens:35,4% spec:89,5% ODA10%: PPV:92%, NPV:28,8%) (AUROC±SEauc:0,46±0,076); CXR: TP: 36, TN:14; FP:5, FN:29; (sens: 55,4%; spec: 73,7%; ODA: 32%; PPV:87,5%, NPV:32,66%) (AUROC±SEauc:0,645±0,068). US: TP:59; TN: 14; FP:5, FN:6 (sens: 90,8%, spec: 73,7%, ODA: 84,9%, PPV:92,2%, NPV:70%) (AUROC±SEauc:0,9417±0,024); CEUS: TP: 63; TN: 19; FP:0; FN:2 (sens: 96,9%; spec: 100% ODA: 97,5%; PPV: 100%, NPV:90,5%) (AUROC±SEauc:0,98±0,01).
Conclusions: Clinical-data and chest X-RAYS are insufficient to obtain a correct diagnosis of CAP in elderly population; US demonstrated a good accuracy to establish CAP, but with a relatively low specificity; in these cases, CEUS is able to give a correct characterization, allowing you to save the need for a chest contrast-enhanced-CT (CECT).