Diagnostic Accuracy of Transthoracic Sonography in Patients with

Pneumonia and Pulmonary embolism Gamal Agmy MD FCCP1, Suzan Sayed MD1 , Azza Said MD2 and Ahmed Kasem MD2

Chest Departments, Assiut University1 , El-Minia University2 , Assiut and El-Minia, Egypt

Introduction In the past the use of lung ultrasound (US) as a diagnostic tool was considered

unjustifiable, on the grounds of conventional knowledge that lungs are filled with air, and that the US beam cannot normally pass through air-filled structures1.Trans-thoracic ultrasonography (TUS) has attracted great interest in the last few years in the diagnosis of some chest diseases that have a high mortality rate 2.

Patients and Methods

Conclusions

Introduction

References

The study population comprised of 17 cases of pneumonia (10 males and 7 females) with a mean age of 52.02 years and 14 cases of pulmonary embolism (9 males and 5 females) with a mean age of 43.4 years. Diagnosis was based on the standard guidelines. Chest X-rays, arterial blood gases, CT chest and TUS were performed. Lung profile and other sonographic abnormalities were assessed by TUS.

LOGO OF YOU UNIVERSITY/INSTITUTION

Aim of Work The aim of this study was to assess the accuracy of bedside trans-thoracic ultrasonography (TUS) for the diagnosis of pneumonia and pulmonary embolism. The sonographic features were also assessed in both diseases.

Results The sensitivity, specificity and diagnostic accuracy of TUS were 88.2%, 87.5% and 93.5% respectively for pneumonia, while, those for embolism were71.4%, 80.9% and 87.1 % respectively. C hest x- ray was diagnostic for pneumonia in 11/ 17 cases (sensitivity 64.7%) whereas TUS was positive in 14/ 17 (sensitivity 82.4%) with a significant higher area under the curve for TUS against chest x-ray (0.84 vs. 0.70, P=0.02).TUS detected pleural effusion in 50% of cases of pneumonia and in 33.3% of cases of embolism, while in contrast. chest radiograph had a lower sensitivity (35% and 20% respectively).

Variable Lung profile No. %

Patients of

pneumonia (n=17)

AB 6 35.3

A profile+ PLAP 6 35.3

B′ profile 4 23.7

C profile 1 5.7

Patients of

pulmonary

embolism (n=14)

A profile 7 50

A′ profile 3 21.4

AB profile 2 14.3

C profile 2 14.3

Studied patients Predominant profile Sensitivity (%) Specificity (%) PPV (%) NPV (%) Accuracy AUC

Pneumonia (n=17) AB, A+PLAPs, B′ 88.2 (15/17) 87.5 (14/16) 88.2(15/17) 87.5(14/16) 93.5(29/31) 0.89

Pulmonary embolism (n=14) A, A′ 71.4 (10/14) 80.9 (17/21) 71.4(10/14) 80.9(17/21) 87.1(27/31) 0.43

Variable Pneumonia (n = 17) Pulmonary embolism (n = 14) P-value

No. % No. %

Lung parenchyma -Normal 3 17.6 5 35.7 0.46 -Abnormal 14 82.4 9 64.3 Shape of abnormality

-Irregular 8 57.1 1 11.1 0.08 -Rounded 2 14.3 3 33.3 -Triangular 4 28.6 5 55.6

Echo texture -Heterogenous 11 78.6 2 27.2 0.02∗ -Homogenous 3 21.4 7 77.8 Air bronchogram

-Present 11 78.6 2 22.2 0.03∗ -Absent 3 21.4 7 77.8

Color flow signal on doppler -Absent 1 7.1 4 44.4 0.1 -Present 13 92.9 5 55.5

Central bronchial reflex -Present 1 7.1 7 77.8 0.001∗ -Absent 13 92.9 2 22.2

Pleural effusion -Present 7 50 3 33.3 0.7 -Absent 7 50 6 66.7

Figure 1.A: Patient clinically had symptoms of pneumonia, on PA and lateral

CXR show no signs of pneumonia (A and B), whereas CT scan (C) confirmed

the right basal consolidation that is shown by lung US also (D).

Figure 2: Patient had pneumonia with AB profile, A profile on right side

and B profile on he left side

Figure 3: (A) Lung ultrasound showing subpleural triangular hypoechoic

lesion in a case of pulmonary embolism. (B) CT chest of the same patient

showing area of pulmonary infarction

Figure 4: Case of pulmonary

embolism shows triangular

subpleural lung consolidation,

vascular sign at the margin, not

central on color Doppler.

Figure 5: A Case of pneumonia,

color Doppler shows an

accentuated, regular pattern of

circulation.

Figure 6: ROC curve for chest sonar and chest -X-ray

for the diagnosis of pneumonia. Table 1: .Sonographic lung profiles among the studied patients.

Table 2: Accuracy of ultrasound profiles vs. CT findings among the studied patients.

Table 3: .Sonographic findings of patients with pneumonia and pulmonary embolism.

TUS is a real time bedside imaging application that can perform well as a rapid diagnostic

technique among patients with pneumonia and pulmonary embolism. TUS seems to be

superior to chest x-ray in diagnosis of pneumonia, pulmonary embolism and associated

pleural effusion.

1-G. Volpicelli :Lung sonography.Ultrasound Med., 32 (1) (2013), pp. 165–171

2-A. Reissig, C. Kroegel, Clinical Chest Ultrasound: From the ICU to the Bronchoscopy Suite,

first ed., vol 37, Bolliger, Basel, Karger, Prog. Respir. Res. (2009)