CT Scan Compared to CXR and LUS in Pneumonia in the Elderly

Summary

Introduction: Pneumonia is a leading cause of mortality and a common indication for antibiotic in elderly patients. However, its diagnosis is often inaccurate. The investigators aim to compare the diagnostic accuracy, the clinical and cost outcomes and the use of antibiotics associated with three imaging strategies in patients \>65 years old with suspected pneumonia in the emergency room (ER): Chest-X ray (CXR, standard of care), low-dose CT scan (LDCT) or lung US (LUS).

Methods and analysis: This is a multicenter randomized superiority clinical trial with three parallel arms. Patients will be allocated in the ER to a diagnostic strategy based on either CXR, LDCT, or LUS. All three imaging modalities will be performed but the results of two of them will be masked during 5 days to the patients, the physicians in charge of the patients and the investigators according to random allocation. The primary objective is to compare the accuracy of LDCT vs CXR- based strategies. As secondary objectives, antibiotics prescription, clinical and cost outcomes will be compared, and the same analyses repeated to compare the LUS and CXR strategies. The reference diagnosis will be established a posteriori by a panel of experts. Based on a previous study, the investigatory expect an improvement of 16% of the accuracy of pneumonia diagnosis using LDCT instead of CXR. Under this assumption, and accounting for 10% of drop out, the enrolment of 495 patients is needed to prove the superiority of LDCT over CRX (alpha error =0.05, beta error=0.10).

Impact of the study: Superiority of the LDCT or LUS strategy over CXR would affect recommendations for the diagnosis of pneumonia in elderly patients. A higher accuracy of one of the strategies may decrease antibiotics overuse and lead to better outcomes and reduced costs.

Conditions

• Pneumonia
• Elderly Infection

Interventions

DIAGNOSTIC_TEST

Chest X-Ray (CXR)

The 3 following imagings will be performed in the emergency room: chest X-Ray (CXR), low-dose CT scan (LDCT) and lung ultrasonography (LUS) will be performed for all included patients, but only one will be available to the clinician in charge of the patient according to the allocation arm. The blinding will be maintained during the first 5 days, and hence will not influence the diagnosis and the treatment of the patient. The clinician in charge will be asked to assess on a 3-level Likert scale the probability of pneumonia (high, intermediate, low level) while considering all available clinical and biological data, plus the imaging modality according to the randomization arm.

DIAGNOSTIC_TEST

Low-dose CT scan (LDCT)

See above in CXR paragraph

DIAGNOSTIC_TEST

Lung ultrasonography (LUS)

See above in CXR paragraph. LUS will be performed by another clinician than the one in charge of the patient

Sponsors & Collaborators

• Insel Gruppe AG, University Hospital Bern

  collaborator OTHER

• Ospedale Regionale di Lugano

  collaborator OTHER

• University Hospital, Geneva

  lead OTHER

Principal Investigators

• Virginie Prendki, Dr · University Hospital, Geneva

Study Design

Allocation

RANDOMIZED

Purpose

DIAGNOSTIC

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

65 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2021-06-17

Primary Completion

2025-05-03

Completion

2025-07-01

Countries

• Switzerland

Study Locations