Community-acquired pneumonia in adults managed in the community
BioMG follows French guidelines. Adapt it to the guidelines and the tests available where you practise.
Community-acquired pneumonia in the community, without severity signs
Imaging (within 3 days, without delaying the antibiotic)
- PA chest X-ray (or pleuropulmonary ultrasound by a trained practitioner)
Laboratory tests: no routine test
- CRP (only if the diagnosis of pneumonia remains doubtful and imaging cannot be obtained quickly)if neededThe 2025 French recommendation does not recommend CRP routinely: alone, it does not make the diagnosis of CAP and does not distinguish bacterial from viral infection [2]. The European ERS/ESCMID recommendation proposes measuring it when pneumonia is suspected in primary care: < 20 mg/L with symptoms for more than 24 hours, pneumonia is very unlikely; > 100 mg/L, it is likely; if doubt persists, chest X-ray [3].
- HIV serology (if serological status unknown)if needednon-French guidelineIn the United Kingdom, BHIVA, BASHH and the BIA (2020) place community-acquired pneumonia among the indicator conditions for which an HIV test is recommended (strong recommendation, grade 1C), the prevalence of undiagnosed infection there reaching at least 1 per 1 000 [4]. The European ECDC (2018) also classes it among these conditions, in primary care as in respiratory medicine [5]. The 2025 SPILF/SPLF recommendation cites HIV only among comorbidities [2]. The French teaching reference asks for HIV screening in pneumonia, while listing it in its laboratory tests only for hospitalised CAP [6].
Do not order
- Routine CRP, for diagnosis or follow-up: not recommended (grade C-1); no threshold is validated to distinguish bacterial from viral pneumonia [2].
- Procalcitonin: not recommended routinely for diagnosis or follow-up (grade C-1) [2].
- Legionella and pneumococcal urinary antigens: not recommended in outpatients (grade C-2); the Legionella urinary antigen is discussed in hospital when suggestive features are present [2].
- Sputum culture: not recommended in outpatients (grade C-2) [2].
- Blood cultures: not recommended in outpatients (expert opinion) [2].
- Viral PCRs (influenza, RSV, SARS-CoV-2) and respiratory syndromic PCR panels: not recommended in outpatient CAP (expert opinion) [2].
No improvement after 72 hours of antibiotics
Imaging
- Chest X-ray if not already done; chest CT if respiratory signs do not improve or worsen
Microbiology tests
- Sputum culture (if sputum is produced, before any change of antibiotic; transport quickly to the laboratory)if neededNICE asks for a sample (for example sputum) to be sent for microbiological examination when symptoms do not improve on antibiotics and this has not already been done [7]. The French recommendation explicitly provides for it only in hospital, notably in case of non-response to first-line treatment at 72 hours, and only on a good-quality sample delivered quickly [2].
Do not order
Sources (10)
- Torres A, Peetermans WE, Viegi G, Blasi F. Risk factors for community-acquired pneumonia in adults in Europe: a literature review. Thorax. 2013;68(11):1057-65.
- Dinh A, Barbier F, Bedos JP, et al. Actualisation des recommandations de prise en charge des pneumonies aiguës communautaires chez l'adulte par la Société de pathologie infectieuse de langue française (SPILF) et la Société de pneumologie de langue française (SPLF). Médecine et Maladies Infectieuses Formation. 2025 (également publié dans Rev Mal Respir. 2025;42(3):168-86 et, en anglais, Infect Dis Now. 2025;55(2):105034).
- Woodhead M, Blasi F, Ewig S, et al.; Joint Taskforce of the European Respiratory Society and European Society for Clinical Microbiology and Infectious Diseases. Guidelines for the management of adult lower respiratory tract infections — full version. Clin Microbiol Infect. 2011;17 Suppl 6:E1-59.
- British HIV Association, British Association for Sexual Health and HIV, British Infection Association. Adult HIV testing guidelines 2020.
- European Centre for Disease Prevention and Control. Public health guidance on HIV, hepatitis B and C testing in the EU/EEA: an integrated approach. Stockholm : ECDC, 2018.
- Collège des enseignants de pneumologie (CEP, SPLF). Item 154 – Infections broncho-pulmonaires communautaires de l'adulte et de l'enfant. Référentiel pour la préparation des épreuves dématérialisées nationales, 9e édition, 2026.
- National Institute for Health and Care Excellence. Pneumonia: diagnosis and management. NICE guideline NG250, 2 septembre 2025 (remplace CG191).
- Metlay JP, Waterer GW, Long AC, et al. Diagnosis and treatment of adults with community-acquired pneumonia. An official clinical practice guideline of the American Thoracic Society and Infectious Diseases Society of America. Am J Respir Crit Care Med. 2019;200(7):e45-e67.
- van Daalen FV, Boersma WG, van de Garde EMW, et al. Management of community-acquired pneumonia in adults: the 2024 practice guideline from the Dutch Working Party on Antibiotic Policy (SWAB) and Dutch Association of Chest Physicians (NVALT). SWAB, 2024.
- National Institute for Health and Care Excellence. Suspected acute respiratory infection in over 16s: assessment at first presentation and initial management. NICE guideline NG237, 31 octobre 2023, mise à jour le 2 septembre 2025.