1. OECD Health Statistics 20172. Clin Infect Dis. 2007 Mar 1;44 Suppl 2:S27-72.3. Thorax. 2009 Oct;64 Suppl 3:iii1-55.4. Clin Microbiol Infect. 2011 Nov;17 Suppl 6:E1-59.5. The JRS Guidelines for the Management of Pneumonia in Adults.6. Müller NL, Franquet T, Lee KS. In: McAllister L, editor. Imaging of pulmonary

infections. Philadelphia, Pa: Wolters Kluwer/Lipponcott Williams �Wilkins; 2007.

Introduction

MethodsConclusions

Table 1. The purposes of chest CT

Introduction Results

Study Design• Retrospective cohort study

Patients • Consecutive pneumonia patients admitted to our department via the emergency room from April 2016 to March 2017 were retrospectively

investigated.

Methods• Following items were extracted from the medical records:

• Sex, age, past medical history, type of pneumonia (CAP/HAP/NHCAP), severity of pneumonia, qSOFA, and presence of pleural effusion on chest X-ray

• Presence or absence of chest CT imaging in the emergency department• Purpose of chest CT imaging (classified into the following 4 categories)

1. Only confirmation of pneumonia2. To investigate extrapulmonary complications3. To investigate pulmonary comorbidities (lung cancer, interstitial pneumonia, and emphysema, etc.)4. To evaluate pulmonary complications (e.g., parapneumonic pleural effusion, empyema, lung abscess, and pneumothorax,

etc.) requiring invasive examination or treatment (thoracentesis, chest tube insertion, and bronchoscopy, etc.)• The results of chest CT interpretations were classified into the following 4 categories.

1. Pneumonia only2. Pneumonia and extrapulmonary lesions (including incidental findings) 3. Pneumonia and pulmonary comorbidities (lung cancer, interstitial pneumonia, and emphysema, etc.)4. Pneumonia and pulmonary complications requiring invasive examination or treatment

Ø The relationships between the purpose of CT imaging and its result were evaluated.Ø Indications of CT imaging for pneumonia were investigated.

Statistical Analysis• The combinations of the purpose and results of chest CT were discussed descriptively.• Based on the results of chest CT, the cases were classified as "CT need group" and "CT unnecessary group". To compare the two groups, a

chi-squared test, Fischer's accuracy test or Mann-Whitney U test were performed.• Logistic regression analysis was used to investigate the statistically independent factors suggesting the necessity of CT.

The purposes of CT no. %1. Only confirmation of pneumonia 173 64.3

2. To investigate extrapulmonary complications 53 19.7

3. To investigate pulmonary comorbidities 33 12.3

4. To evaluate pulmonary complicataions requiring invasive examination or treatment

10 3.7

total 269 100

CT findings no. (%)1. Pneumonia only 160 (92.5)

2. Pneumonia and extrapulmonary lesions 1 (0.6)

3. Pneumonia and pulmonary comorbidities 4 (2.3)

4. Pneumonia and pulmonary complications requiring invasive examination or treatment

8 (4.6)

total 173

Table 2. The results of chest CT interpretation.

Utility of CT No(160)

Yes(109)

P-value

Cerebrovascular disease 0.13

noyes

11545

8821

COPD 0.18

noyes

13030

9613

Cardiovascular disease 0.50

noyes

10753

7831

IP 0.05

noyes

1555

9910

Chronic kidney disease 0.14

noyes

13624

1009

Chronic liver disease 1

noyes

15010

1027

Lung cancer 0.38

noyes

1519

9910

Malignancy 0.34

noyes

12436

7831

In-hospital mortality12

�7.5%�16

�14.7%�0.09

Utility of CT No(160)

Yes(109)

P-value

A-DROP 0.03

012345

16323250246

8223919192

CURB-65 0.95

012345

12385244122

727412581

qSOFA 0.19

0123

20696110

2445364

PORT Class 0.51

12345

01896271

19103950

PSI 127 126 0.80

Utility of CT No(160)

Yes(109)

P-value

Age (yr) 82 80 0.12

Sex 0.01

MaleFemale

8080

7237

Nursing home residence 0.06

noyes

9763

7930

Altered mentation 0.24

noyes

8179

6445

BT (℃) 37.8 37.5 0.04

BUN (mg/dl) 19 20 0.28

GCS 14 15 0.10

Glu (mg/dl) 124 135 0.03

Hct (%) 35.9 36.3 0.86

Na (mEq/l) 136 136 0.91

PR (/min) 96.5 95.0 0.96

RR (/mim) 24 24 0.35

sBP (mmHg) 125 124 0.79

Pleural effusion on chest X-ray

<0.01

noyes

14119

8227

ICU admission 0.16

noyes

1600

1072

Background• In Japan, physicians can order CT scans easily for diagnosis of pneumonia at many institutions.

- The number of CT scanners is 107.2 per million population (No. 1 in OECD member countries)(Figure 1)

- The number of CT exams is 230.8 times per 1000 population (No. 2 in OECD member countries)• Actually, in our hospital, most hospitalized patients with pneumonia from emergency room undergo

chest CT.

• IDSA/ATS guidelines, BTS guidelines, and ERS guidelines do not recommend performing chest CT when pneumonia is suspected by chest X-ray.2,3,4

• The Japanese Respiratory Society (JRS) Guidelines for the Management of Pneumonia in Adults 20175 recommends obtaining chest CT when:1. It is necessary to differentiate from other diseases (e.g., malignancy, pulmonary

thromboembolism, heart failure, and tuberculosis, etc.)2. There is a need to investigate the accurate location of complications requiring invasive

procedures (thoracentesis, chest tube insertion, and bronchoscopy, etc.)3. The patient has underlying lung diseases that make the diagnosis of pneumonia difficult.

• It was also reported that general indications of CT for community-acquired pneumonia (CAP) included disease severity.6

• However, there is little evidence that supports this recommendation.

Table 3. Univariate analysis comparing patients classified according to “retrospectively, whether the CT was useful or not”. Table 4. Multiple logistic regression analysis about CT utility

Figure 1. CT scanners, 2015 (or nearest year)1

Conclusions• In our institution, 90.3% of patients hospitalized via ER due to

pneumonia had undergone chest CT at the diagnosis.• 64.3% of CT imaging at ER did not follow the JRS guidelines, and

only 7.5% of that CT imaging was useful in the management of pneumonia. Therefore, the recommendations of the JRS guidelines were thought to be generally correct.

• Logistic regression analysis revealed that the disease severity was not significantly associated with the utility of CT.

Limitations• Single-center, retrospective study.• Outpatients were not included.

There is no potential conflict of interest.

Additional Diagnostic Value of Chest CT in Patients with Suspected Pneumonia.Takuto Sueyasu, M.D., Kazunori Tobino, M.D., Ph.D., Masanobu Okahisa, M.D, Yuki Goto, M.D,

Kojin Murakami, M.D, Saori Nishizawa, M.D, Miyuki Munechika, M.D., Kohei Yoshimine, M.D., -Department of Respiratory Medicine, Iizuka Hospital, Fukuoka, Japan

Aims• To examine the validity of the recommendation of the JRS guidelines for pneumonia patients hospitalized via ER.• To investigate whether severity is involved in the indications of CT imaging in the initial management of pneumonia in the ER.

Bibliography

Figure 2. Frequency of chest CT imaging at ER.

7.5%

odds ratio lower .95 upper .95 p-value

(Intercept)SexPleural effusion on

chest X-rayCOPDIPCardiovascular diseaseMalignancyADROP

2.120.493.28

0.384.120.771.430.89

0.810.291.59

0.181.250.430.780.72

5.570.846.75

0.8213.61.372.601.10

0.130.01

<0.01

0.010.020.370.250.27

269 (90.3%)

25 (9.7%)