Pneumonia: Empiric Treatment Based on Patient Population

Pneumonia: Empiric Treatment Based on Patient Population

Empiric Treatment Based on Patient Population


Neonates <5 days old. Caused by maternal vaginal flora, including Group A and B Streptococcus, E. coli, Chlamydia, Treponema. Treat with ampicillin and gentamicin or third-generation cephalosporin.

Neonates (5 days to 1 month). Group A or B Streptococcus, S. aureus, E. coli, Chlamydia. Treat with penicillinase-resistant penicillin (nafcillin). Consider vancomycin if MRSA is prevalent. For cough and infiltrates without a fever, consider Chlamydia trachomatis even in the absence of conjunctivitis. These children should be treated with a macrolide.

Children (1month to 5 years). 80% of mild-to-moderate cases are viral. Bacterial causes include pneumococcus, H. influenzae, also chlamydia or Mycoplasma. Treat with extended spectrum macrolide for outpatients (e.g., clarithromycin, azithromycin). Consider third-generation cephalosporin aminoglycoside for inpatients.

Children over 5 years. Same as adults without comorbid factors.

Adult outpatients without comorbid factors. Most common agents are pneumococcus, Mycoplasma, Chlamydia pneumoniae. Treat with macrolide (tetracycline if intolerant). Must also cover H. influenzae in smokers, so use extended spectrum macrolide (azithromycin or clarithromycin).

Adult outpatients with comorbid factors (smoking, age >60, diabetes, emphysema, heart disease, etc). If multiple comorbid factors, consider inpatient treatment. Common etiologies same as those without comorbid factors, but increased prevalence of gram-negative rods and Moraxella. Treat with TMP/SMX + macrolide or Augmentin + macrolide. Extended spectrum macrolide or extended spectrum fluoroquinolone (e.g., levo-floxacin) may be used as monotherapy.

Adult inpatients not requiring ICU. Similar organisms but increased incidence of Legionella and gram-negative rods. Treat with third- generation cephalosporin + macrolide, beta-lactam with inhibitor + macrolide. Consider monotherapy with extended spectrum macrolide (azithromycin IV) or extended spectrum fluoroquinolone (e.g., levofloxacin).

Adult inpatients requiring ICU. Most common agents are pneumococcus, gram-negative rods, and Legionella. Mycoplasma in elderly. Therapy includes a macrolide plus a third-generation cephalosporin. Consider adding an aminoglycoside to cover gram-negative rods especially if the patient is hypotensive.

Adult, hospital-acquired pneumonia. As patients remain in the hospital, the oropharynx become increasingly colonized with gram-negative rods and MRSA. Therefore, for hospital acquired pneumonias that develop within the first 2-5 days after admission, treat with a third-generation cephalosporin or fluoroquinolone. After this, aggressive gram-negative rods are common so treat with two anti-pseudomonal agents (aminoglycoside or ciprofloxacin + antipseudomonal beta-lactam like piperacillin, piperacillin-tazobactam, imipenem), consider adding vancomycin for MRSA.