What are the recommended diagnostic tests for a patient presenting with suspected bacterial pneumonia in primary care?

For a patient presenting with suspected bacterial pneumonia in primary care, the recommended diagnostic approach primarily relies on clinical assessment supported by selective use of point-of-care tests rather than routine microbiological or imaging investigations initially.

Clinical diagnosis is based on symptoms and signs of lower respiratory tract infection, such as cough, sputum production, breathlessness, fever, and focal chest signs, in the absence of alternative explanations ¹.

Risk assessment using the CRB65 score is advised to stratify severity and guide management decisions, including the need for hospital referral ¹,².

Point-of-care C-reactive protein (CRP) testing can be used to support antibiotic prescribing decisions when it is unclear if antibiotics are needed. Specifically, immediate antibiotics are recommended if CRP is >100 mg/L, a back-up prescription considered if CRP is 20–100 mg/L, and antibiotics withheld if CRP is <20 mg/L ².

Microbiological testing such as rapid point-of-care bacterial or viral tests, including influenza tests, is not routinely recommended in primary care to guide antibiotic prescribing but may be used for surveillance or infection control purposes ².

Chest X-ray is not routinely performed in primary care to confirm diagnosis but is recommended if symptoms persist despite treatment, if there is suspicion of complications or underlying malignancy, or if the patient is at higher risk (e.g., smokers, age >50 years) ¹,³.

Recent literature highlights that while point-of-care tests for respiratory pathogens have potential benefits, their routine use in primary care is limited by variable accuracy and unclear impact on clinical outcomes, supporting current guideline recommendations to rely on clinical assessment and CRP testing primarily (Nairz and Weiss, 2025).

In summary, the diagnostic tests recommended in primary care for suspected bacterial pneumonia are clinical evaluation, CRP point-of-care testing to guide antibiotic use, and selective use of chest X-ray and microbiological tests based on clinical judgement and patient risk factors ¹,²,³ (Nairz and Weiss, 2025).