Management of Community-Acquired Pneumonia in a 45-Year-Old Man

Admit this patient to the hospital and initiate combination therapy with ceftriaxone and azithromycin. 1

Rationale for Hospital Admission

This patient requires hospitalization based on several key factors:

Severity assessment is mandatory for all patients with community-acquired pneumonia (CAP) to determine the appropriate level of care 2, 1
The presence of fever for 3 days with confirmed pneumonia (right lower lobe infiltrate) necessitates formal evaluation of adverse prognostic features including oxygen saturation, respiratory rate, blood pressure, and mental status 2, 1
Delayed oxygenation assessment beyond 3 hours is an independent risk factor for death, making immediate hospital evaluation critical 1
Without additional information confirming this patient meets low-risk criteria (such as age <50, no comorbidities, normal vital signs, and oxygen saturation >92%), outpatient management cannot be safely recommended 2, 3

Ceftriaxone plus azithromycin is the appropriate empiric regimen for hospitalized CAP patients:

Combination therapy provides coverage for both typical bacterial pathogens (Streptococcus pneumoniae, Haemophilus influenzae) and atypical organisms (Mycoplasma pneumoniae, Chlamydia pneumoniae, Legionella species) 2
Inappropriate initial antimicrobial treatment is associated with significantly increased hospital mortality, making broad empiric coverage essential 1
The macrolide component (azithromycin) is critical as atypical pathogens cannot be reliably excluded clinically and may account for a substantial proportion of CAP cases 2, 3

Intravenous amoxicillin monotherapy is insufficient because:

It lacks coverage for atypical pathogens, which are common causes of CAP in this age group 2
Monotherapy with a beta-lactam alone does not meet guideline recommendations for hospitalized patients 2, 1

Outpatient treatment with azithromycin alone is inappropriate because:

Without documented low-risk status and stable vital signs, this patient requires hospital-level monitoring 2, 1
Azithromycin monotherapy lacks adequate coverage for S. pneumoniae, particularly if resistance is present 2

Outpatient treatment with cefuroxime is inadequate because:

Upon hospital admission, the following must occur immediately:

Initiate antibiotic therapy within 1 hour of presentation to reduce mortality 1
Measure oxygen saturation immediately and initiate supplemental oxygen to maintain SpO₂ >92% 2, 1
Obtain chest radiograph (already done), complete blood count, serum electrolytes, glucose, liver and renal function tests 1
Assess for volume depletion and initiate intravenous fluid resuscitation if needed 2, 1
Collect blood cultures before antibiotic administration 2

Monitor vital signs (temperature, respiratory rate, pulse, blood pressure, mental status, oxygen saturation) at least twice daily 2, 1
Regular reassessment of severity is mandatory to adjust management appropriately 2, 1
Clinical improvement should be evident by Day 3, with progressive clinical stability expected within 24-72 hours of appropriate therapy 2
If the patient remains febrile or unwell at 48-72 hours, reevaluation with repeat chest radiograph and consideration of complications or alternative diagnoses is necessary 2

Do not delay antibiotic administration while awaiting diagnostic test results—empiric therapy must begin within 1 hour 1
Do not use monotherapy in hospitalized CAP patients, as combination therapy is the standard of care 2, 1
Do not discharge patients prematurely—ensure clinical stability criteria are met before considering transition to outpatient management 2