For an overweight patient with fever and cough in the summer, what is the most appropriate initial imaging test to evaluate for pneumonia?

• A. Ultrasound
• B. Chest X-Ray
• C. MRI
• D. CT Chest

Answer: (B)

When you suspect pneumonia, start with a chest radiograph. It’s the quickest, most accessible way to visualize lung fields and look for consolidation, air-space disease, or pleural effusion that would support a pneumonia diagnosis. A standard two-view chest X-ray (often PA and lateral) provides a reliable baseline and helps guide treatment decisions in a practical ED or clinic setting.

Other imaging modalities aren’t the initial choice. Ultrasound can detect some pleural fluid and peripheral consolidations, but air-filled lungs don’t image well with ultrasound, and results are highly operator-dependent, so it’s not used as the first-line test for pneumonia. MRI isn’t practical here due to cost, time, and limited added benefit in acute pneumonia. CT chest is more sensitive and can reveal subtle involvement or complications, but it incurs higher radiation and cost and is reserved for cases where the chest X-ray is inconclusive or there are atypical features, complications, or a need to evaluate other structures.

In overweight patients, the chest X-ray remains the most efficient initial test, though image quality can be affected. If the radiograph is inconclusive but clinical suspicion remains high, a CT scan may be considered to further evaluate.