Severity assessment outside hospital

1.2.1.

If a clinical diagnosis of community-acquired pneumonia has been made, carry out a risk assessment using the CRB65 scoring system (see box 1). [2014, amended 2023]

1.2.2.

Use clinical judgement together with the CRB65 score (bearing in mind this can be affected by other factors, for example, comorbidities or pregnancy) to inform decisions about whether people with a clinical diagnosis of community-acquired pneumonia need hospital assessment as follows:

• consider hospital assessment for people with a CRB65 score of 2 or more
• discuss the options with people with a score of 1 and make a shared decision about the best care pathways for them, for example supported home-based care using a virtual ward or community intervention team
• consider home based care for patients with a CRB65 score of 0.

Severity assessment in hospital

1.2.3.

When a diagnosis of community-acquired pneumonia is made at presentation to hospital, determine whether people are at low, intermediate or high risk of death using the CURB65 score (see box 2).

1.2.4.

Use clinical judgement in conjunction with the CURB65 score to guide the management of community-acquired pneumonia, as follows:

• consider home-based care for people with a CURB65 score of 0 or 1
• consider hospital-based care for people with a CURB65 score of 2 or more
• consider intensive care assessment for people with a CURB65 score of 3 or more.

1.2.5.

Stratify people presenting with community-acquired pneumonia into those with low-, moderate- or high-severity disease. The grade of severity will usually correspond to the risk of death.

Microbiological tests

1.2.6.

Do not routinely offer microbiological tests to people with low-severity community-acquired pneumonia.

1.2.7.

For people with moderate- or high-severity community-acquired pneumonia:

• take blood and sputum cultures and
• consider pneumococcal and legionella urinary antigen tests.

Timely diagnosis and treatment

1.2.8.

Put in place processes to allow diagnosis (including X-rays) and treatment of community-acquired pneumonia within 4 hours of presentation to hospital.

Antibiotic therapy

See NICE's guideline on pneumonia (community-acquired): antimicrobial prescribing for recommendations on antibiotic therapy.

Glucocorticoid treatment

1.2.17.

Do not routinely offer a glucocorticoid to people with community-acquired pneumonia unless they have other conditions for which glucocorticoid treatment is indicated.

Monitoring in hospital

1.2.18.

Consider measuring a baseline C-reactive protein concentration in people with community-acquired pneumonia on admission to hospital, and repeat the test if clinical progress is uncertain after 48 to 72 hours.

Safe discharge from hospital

1.2.19.

Do not routinely discharge people with community-acquired pneumonia if in the past 24 hours they have had 2 or more of the following findings:

• temperature higher than 37.5°C
• respiratory rate 24 breaths per minute or more
• heart rate over 100 beats per minute
• systolic blood pressure 90 mmHg or less
• oxygen saturation under 90% on room air
• abnormal mental status
• inability to eat without assistance.

1.2.20.

Consider delaying discharge for people with community-acquired pneumonia if their temperature is higher than 37.5°C.

Patient information

1.2.21.

Explain to people with community-acquired pneumonia that after starting treatment their symptoms should steadily improve, although the rate of improvement will vary with the severity of the pneumonia, and most people can expect that by:

• 1 week: fever should have resolved
• 4 weeks: chest pain and sputum production should have substantially reduced
• 6 weeks: cough and breathlessness should have substantially reduced
• 3 months: most symptoms should have resolved but fatigue may still be present
• 6 months: most people will feel back to normal.

1.2.22.

Advise people with community-acquired pneumonia to consult their healthcare professional if they feel that their condition is deteriorating or not improving as expected.

Antibiotic therapy

See NICE's guideline on pneumonia (hospital-acquired): antimicrobial prescribing for recommendations on antibiotic therapy for hospital-acquired pneumonia.

1.3.1.

Deleted.

1.3.2.

Deleted.

1.3.3.

Deleted.

Clinical diagnosis of community-acquired pneumonia

Diagnosis based on symptoms and signs of lower respiratory tract infection in a patient who, in the opinion of the GP and in the absence of a chest X-ray, is likely to have community-acquired pneumonia. This might be because of the presence of focal chest signs, illness severity or other features.

Community-acquired pneumonia

Pneumonia that is acquired outside hospital. Pneumonia that develops in a nursing home resident is included in this definition. When managed in hospital the diagnosis is usually confirmed by chest X-ray.

Hospital-acquired pneumonia

Pneumonia that develops 48 hours or more after hospital admission and that was not incubating at hospital admission. When managed in hospital the diagnosis is usually confirmed by chest X-ray. For the purpose of this guideline, pneumonia that develops in hospital after intubation (ventilator-associated pneumonia) is excluded from this definition.

Lower respiratory tract infection

An acute illness (present for 21 days or less), usually with cough as the main symptom, and with at least 1 other lower respiratory tract symptom (such as fever, sputum production, breathlessness, wheeze or chest discomfort or pain) and no alternative explanation (such as sinusitis or asthma). Pneumonia, acute bronchitis and exacerbation of chronic obstructive airways disease are included in this definition.

Mortality risk

The percentage likelihood of death occurring in a patient in the next 30 days.

Severity assessment

A judgement by the managing clinician as to the likelihood of adverse outcomes in a patient. This is based on a combination of clinical understanding and knowledge in addition to a mortality risk score. The difference between categories of severity and mortality risk can be important. Typically the mortality risk score will match the severity assessment. However, there may be situations where the mortality score does not accurately predict mortality risk and clinical judgement is needed. An example might be a patient with a low mortality risk score who has an unusually low oxygen level, who would be considered to have a severe illness.

Why this is important

Current practice and evidence suggest that giving a combination of antibiotics to people with moderate- to high-severity community-acquired pneumonia reduces mortality. However, no randomised controlled trial has looked at using urinary antigen testing to target treatment. If effective, such targeted treatment could improve antibiotic stewardship, increase compliance and potentially reduce costs.

Why this is important

The recommended duration of antibiotic therapy for adults hospitalised with moderate- to high-severity community-acquired pneumonia is based on evidence of very low quality; no relevant clinical trials were identified by NICE. The burden of community-acquired pneumonia is large, and its treatment accounts for a high proportion of antibiotic use in hospitals. Overuse of antibiotics is associated with antimicrobial resistance, which is a national and global priority.

Why this is important

Type I respiratory failure is a common feature of pneumonia. Mild type I respiratory failure is easily corrected with low levels of supplemental oxygen, whereas severe life-threatening hypoxemia needs immediate intubation and invasive ventilation. Research into whether continuous positive pressure ventilation improves gas exchange and subsequent outcomes, such as mortality, could help improve care for people with respiratory failure between these extremes.

Why this is important

Data are limited on the microbiology of hospital-acquired pneumonia to guide antibiotic therapy. Hospital-acquired infections can be caused by highly resistant pathogens that need treatment with extended-spectrum antibiotics (for example, extended-spectrum penicillins, third-generation cephalosporins, aminoglycosides, carbapenems, linezolid, vancomycin, or teicoplanin), as recommended by British Society of Antimicrobial Chemotherapy guidance. Because routine microbial tests lack sensitivity and take 24–48 hours to identify a causative pathogen, patient characteristics are used to guide antibiotic choice. However, this may lead to unnecessary use of extended-spectrum antibiotics in people infected with non-resistant organisms, and inappropriate use of first-line antibiotics (such as beta-lactam stable penicillins, macrolides or doxycycline) in people infected with resistant organisms.

Rapid diagnostic tests to identify causative bacterial pathogens and determine whether they are resistant to antibiotics may have a role in guiding antibiotic choice for postoperative hospital-acquired pneumonia.

To limit population variability and include high-risk people spending time in intensive care, studies should include postoperative patients from different surgical specialties.