In a patient who presents without the classic respiratory signs and symptoms (e.g., deterioration, delirium, abdominal pain), include pneumonia in the differential diagnosis.
In a patient with signs and symptoms of pneumonia, do not rule out the diagnosis on the basis of a normal chest X-ray film (e.g., consider dehydration, neutropenia, human immunodeficiency virus [HIV] infection).
In a patient with a diagnosis of pneumonia, assess the risks for unusual pathogens (e.g., a history of tuberculosis, exposure to birds, travel, HIV infection, aspiration).
In patients with pre-existing medical problems (e.g., asthma, diabetes, congestive heart failure) and a new diagnosis of pneumonia:
Treat both problems concurrently (e.g., with prednisone plus antibiotics).
Adjust the treatment plan for pneumonia, taking into account the concomitant medical problems (e.g., be aware of any drug interactions, such as that between warfarin [Coumadin] and antibiotics).
Identify patients, through history-taking, physical examination, and testing, who are at high risk for a complicated course of pneumonia and would benefit from hospitalization, even though clinically they may appear stable.
In the patient with pneumonia and early signs of respiratory distress, assess, and reassess periodically, the need for respiratory support (bilevel positive airway pressure, continuous positive airway pressure, intubation) (i.e., look for the need before decompensation occurs).
For a patient with a confirmed diagnosis of pneumonia, make rational antibiotic choices (e.g., outpatient + healthy = first-line antibiotics; avoid the routine use of “big guns”).
In a patient who is receiving treatment for pneumonia and is not responding:
Revise the diagnosis (e.g., identify other or contributing causes, such as cancer, chronic obstructive pulmonary disease, or bronchospasm), consider atypical pathogens (e.g., Pneumocystis carinii, TB) and diagnose complications (e.g., empyema, pneumothorax).
Modify the therapy appropriately (e.g., change antibiotics).
Identify patients (e.g., the elderly, nursing home residents, debilitated patients) who would benefit from immunization or other treatments (e.g., flu vaccine, Pneumovax, ribavarine) to reduce the incidence of pneumonia.
In patients with a diagnosis of pneumonia, ensure appropriate follow-up care (e.g., patient education, repeat chest X-ray examination, instructions to return if the condition worsens).
In patients with a confirmed diagnosis of pneumonia, arrange contact tracing when appropriate (e.g., in those with TB, nursing home residents, those with legionnaires’ disease).
Typical: Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis
Atypical: Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella spp
Aspiration: Bacteroides (anaerobes)
No hospitalization within 14d of onset OR <4d prior to onset
Two symptoms (fever, rigors, cough change, pleuritic chest pain, SOB), AND auscultatory findings (localized crackles, bronchial breath sounds), AND X-ray opacity
New or change in cough
Pleuritic chest pain
Antibiotics or hospitalization in past 3 months
Note: The only significant findings for a bacterial pneumonia is acute onset (LR+3.6, LR-0.31) and age >65 (LR+2.7, LR-0.43)
Chills, pleuritic chest pain, purulent sputum, signs of consolidation on auscultation were not helpful in making the diagnosis
Note: Adults with an acute respiratory infection and normal vital signs/pulmonary exam are unlikely (~0.4%) to have pneumonia
Chest X-ray (PA and lateral) required for diagnosis according to IDSA
Highly suggested in children as well according to CPS
CRP was the most accurate lab test
CRP < 10 mg/L; LR- = 0.27
CRP > 20 mg/L; LR+ = 2.08
CRP > 50 mg/L; LR+ = 3.68
CRP > 100 mg/L; LR+ = 5.79
Procalcitonin had a good LR+, but a minimally useful LR-
Procalcitonin > 0.25 mcg/L and 0.50 mcg/L; LR+ = 5.43 and 8.25
Leukocytosis was only modestly, if at all, accurate (> 9.5 - 10.5; LR+ = 3.15)
Consider if severe
Urine legionella/pneumococcal Ag
Positive even after days of antibiotic therapy
Sputum gram stain and culture (r/o MRSA, P. aeruginosa)
Nasopharyngeal swab viral PCR (influenza, coronavirus, etc...)
If not improving can monitor CRP / Procalcitonin
Pneumonia Severity Index (PSI) more evidence than CURB-65 to determine outpatient vs inpatient treatment
Drain large pleural effusions or if suspect empyema
If no antibiotics in past three months
Clarithromycin 500mg PO BID x7d or Azithromycin 500mg PO daily x1 day then 250mg PO daily x 4 days or Doxycycline 100mg PO BID x 7 days
Promote less resistance to macrolides by using clarithromycin
Amoxicillin 1g PO TID x7d (less emphasis on covering atypicals)
If comorbidities or recent antibiotics
Amoxicillin with atypical coverage (Clarithromycin or Azithromycin or Doxycycline)
If non-anaphylactic penicillin allergy
Cefuroxime or Cefadroxil + atypical coverage (consider monitor in office 1-2h)
Anaphylactic penicillin allergy
Levofloxacin or Moxifloxacin as below
Second-line (after failed 72-96h)
Levofloxacin 750mg PO daily x 5 days or Moxifloxacin 400mg PO daily x 7d
If hospitalized and intensive care
Cefotaxime 1-2g IV q8h or Ceftriaxone 1-2g IV q12-24h AND Levofloxacin or Moxifloxacin or Azithromycin
Note: Ceftriaxone superior to Pip/Tazo (as 15% Strep pneumo resistant to Pip/Tazo in community-acquired pneumonia)
Consider covering for legionella if risk factors
Elderly, immunosuppression, smoker, lung disease
Neurological (Confusion/Weakness/Gen det)
Electrolytes (Hyponatremia. hypophosphatemia, renal/hepatic dysfunction, thrombocytopenia, leukococytosis)
Hotel, cruise ships, residence (water reservoir contamination)
Return if no improvements after 72h of treatment (fever should not return after 3d)
IDSA recommends not routinely obtaining follow-up imaging if symptoms resolve within 7 days (low quality evidence)
Repeat CXR in 6w (r/o underlying disease) if
>50yo or immunosuppressed, lung disease, alcohol, smoker, >5% weight loss in past month
Pneumococcal >65yo or comorbidity
Prevents invasive pneumococcal disease (bacteremia)
ATS/IDSA 2019. https://www.atsjournals.org/doi/full/10.1164/rccm.201908-1581ST
INESSS 2017. http://www.inesss.qc.ca/fileadmin/doc/CDM/UsageOptimal/Guides-serieI/Guide_Pneumo_Web.pdf
INESSS 2016. https://www.inesss.qc.ca/fileadmin/doc/CDM/UsageOptimal/Guides-serieI/Guide-Pneumonie-Enfant.pdf
CPS 2015. https://www.cps.ca/en/documents/position/pneumonia-management-children-youth
NICE 2014. https://www.nice.org.uk/guidance/cg191/evidence/full-guideline-193389085
AAFP 2011. http://www.aafp.org/afp/2011/0601/p1299.html