A 70-year-old lady was referred by GP with h/o productive cough for 10 days. She completed a course of Amoxicillin with no improvement in her symptoms.

She did not have any previous medical history and did not take any regular medications.

She was a heavy smoker for 40 years. She lived alone independently.

Examination findings are as follows:

Temp. 37.0°C

HR: 110/ min

B.P: 138/70 mm of Hg

CVS: I-II normal

Lungs: RR – 20/ min

            Crepts+ at right base

            O2 saturation: 95% on room air

CNS: No focal neurology

Lab investigations:

WBC: 32 X 10 (9)/ L

Neutrophils: 28 X 10 (9)/L

CRP: 284 mg/dL

CXR: Cavitating consolidation at right lower lobe

NICE guidance recommends

• No antibiotics if CRP <20mg/dL
• Delayed antibiotics if CRP 20 -100mg/dL
• Antibiotic treatment if CRP >100mg/ dL

(NICE does recommend CURB-65 as decision making tool for hospital admission or discharge)

Link to NICE guidance

This is the excerpt from BTS guideline on management of community acquired pneumonia.

The acute phase reactant CRP is a sensitive marker of progress in pneumonia. Prospective studies have shown that repeat measurement of CRP at day 3 or 4 is helpful in identifying patients with treatment failure.

A failure of CRP to fall by 50% is associated with increased 30-day mortality, increased need for mechanical ventilation and/or inotropic support and increased incidence of complicated pneumonia such as empyema.

Link to BTS guidance

C-reactive protein (CRP) is an acute phase protein synthesized by the liver primarily in response inflammation.

Some clinicians believe that CRP is CRAP and it does not add any value in the diagnosis or management of patients.

Many studies have refuted this claim. It is evident that higher CRP levels are associated with the worse outcomes. It is the clinician’s responsibility  to correlate result with the patient’s presentation. Ultimately the decision should be based on the overall picture and involving patient in the decision making process.

• Chalmers JD, Singanayagam A, Hill AT. C-reactive protein is an independent predictor of severity in community-acquired pneumonia. Am J Med. 2008 Mar;121(3):219-25. doi: 10.1016/j.amjmed.2007.10.033. PMID: 18328306.

• Bruns AH, Oosterheert JJ, Hak E, Hoepelman AI. Usefulness of consecutive C-reactive protein measurements in follow-up of severe community-acquired pneumonia. Eur Respir J. 2008 Sep;32(3):726-32. doi: 10.1183/09031936.00003608. Epub 2008 May 28. PMID: 18508833.

• Coelho L, Póvoa P, Almeida E, Fernandes A, Mealha R, Moreira P, Sabino H. Usefulness of C-reactive protein in monitoring the severe community-acquired pneumonia clinical course. Crit Care. 2007;11(4):R92. doi: 10.1186/cc6105. PMID: 17723153; PMCID: PMC2206486.