Pneumonia in adults: NICE guidance on diagnosis and management

Pneumonia is an infection of the lung tissue. When a person has pneumonia the air sacs in their lungs become filled with microorganisms, fluid and inflammatory cells and their lungs are not able to work properly. Diagnosis of pneumonia is based on symptoms and signs of an acute lower respiratory tract infection, and can be confirmed by a chest X‑ray showing new shadowing that is not due to any other cause (such as pulmonary oedema or infarction).

In the year 2014, National Clinical Guideline Centre came out with the guidelines on Pneumonia in adults: diagnosis and management.

Following are its major recommendations:-

Presentation with Lower Respiratory Tract Infection

For people presenting with symptoms of lower respiratory tract infection in primary care, consider a point of care C-reactive protein test if after clinical assessment a diagnosis of pneumonia has not been made and it is not clear whether antibiotics should be prescribed. Use the results of the C-reactive protein test to guide antibiotic prescribing in people without a clinical diagnosis of pneumonia as follows:

• Do not routinely offer antibiotic therapy if the C-reactive protein concentration is less than 20 mg/litre.


• Consider a delayed antibiotic prescription (a prescription for use at a later date if symptoms worsen) if the C-reactive protein concentration is between 20 mg/litre and 100 mg/litre.


• Offer antibiotic therapy if the C-reactive protein concentration is greater than 100 mg/litre.

Community-Acquired Pneumonia

Severity Assessment in Primary Care

When a clinical diagnosis of community-acquired pneumonia is made in primary care, determine whether patients are at low, intermediate or high risk of death using the CRB65 score

Use clinical judgement in conjunction with the CRB65 score to inform decisions about whether patients need hospital assessment as follows:

• Consider home-based care for patients with a CRB65 score of 0.


• Consider hospital assessment for all other patients, particularly those with a CRB65 score of 2 or more.

Severity Assessment in Hospital

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

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

• Consider home-based care for patients with a CURB65 score of 0 or 1.


• Consider hospital-based care for patients with a CURB65 score of 2 or more.


• Consider intensive care assessment for patients with a CURB65 score of 3 or more.

Stratify patients 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

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

For patients 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

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

Offer antibiotic therapy as soon as possible after diagnosis, and certainly within 4 hours to all patients with community-acquired pneumonia who are admitted to hospital.

Antibiotic Therapy

Low-Severity Community-Acquired Pneumonia

Offer a 5-day course of a single antibiotic to patients with low-severity community-acquired pneumonia.

Consider amoxicillin in preference to a macrolide or a tetracycline for patients with low-severity community-acquired pneumonia. Consider a macrolide or a tetracycline for patients who are allergic to penicillin.

Consider extending the course of the antibiotic for longer than 5 days as a possible management strategy for patients with low-severity community-acquired pneumonia whose symptoms do not improve as expected after 3 days.

Explain to patients with low-severity community-acquired pneumonia treated in the community, and when appropriate their families or carers, that they should seek further medical advice if their symptoms do not begin to improve within 3 days of starting the antibiotic, or earlier if their symptoms are worsening.

Do not routinely offer patients with low-severity community-acquired pneumonia:

• A fluoroquinolone


• Dual antibiotic therapy

Moderate- and High-Severity Community-Acquired Pneumonia

Consider a 7- to 10-day course of antibiotic therapy for patients with moderate- or high-severity community-acquired pneumonia.

Consider dual antibiotic therapy with amoxicillin and a macrolide for patients with moderate-severity community-acquired pneumonia.

Consider dual antibiotic therapy with a beta-lactamase stable beta-lactam and a macrolide for patients with high-severity community-acquired pneumonia. Available beta-lactamase stable beta-lactams include co-amoxiclav, cefotaxime, ceftaroline fosamil, ceftriaxone, cefuroxime and piperacillin with tazobactam.

Glucocorticosteroid Treatment

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

Monitoring in Hospital

Consider measuring a baseline C-reactive protein concentration in patients 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

Do not routinely discharge patients 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

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

Patient Information

Explain to patients 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

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

Hospital-Acquired Pneumonia

Antibiotic Therapy

Offer antibiotic therapy as soon as possible after diagnosis, and certainly within 4 hours, to patients with hospital-acquired pneumonia.

Choose antibiotic therapy in accordance with local hospital policy (which should take into account knowledge of local microbial pathogens) and clinical circumstances for patients with hospital-acquired pneumonia.

Consider a 5- to 10-day course of antibiotic therapy for patients with hospital-acquired pneumonia.

You can read the full guideline by clicking on the following link:

https://www.nice.org.uk/guidance/cg191