What determines whether community-acquired pneumonia (CAP) can be treated as an outpatient versus an inpatient?

From the Guidelines

The decision to treat community-acquired pneumonia (CAP) as an outpatient versus inpatient depends primarily on the severity of illness and risk factors for complications, with patients having mild symptoms, stable vital signs, no significant comorbidities, and adequate social support typically being treated as outpatients. The CURB-65 score (Confusion, Uremia with BUN >19 mg/dL, Respiratory rate ≥30, Blood pressure <90/60 mmHg, and age ≥65) or the Pneumonia Severity Index (PSI) can help guide this decision, with lower scores favoring outpatient management 1.

Some key factors to consider when deciding between outpatient and inpatient treatment include:

• Severity of symptoms
• Presence of comorbidities
• Ability to take oral medications
• Social support for outpatient care
• Risk of complications, such as respiratory failure or sepsis

Outpatient treatment usually consists of oral antibiotics, such as:

• Amoxicillin 1g three times daily for 5 days
• Doxycycline 100mg twice daily for 5-7 days
• Azithromycin 500mg on day 1 followed by 250mg daily for 4 more days

In contrast, patients requiring hospitalization typically have severe symptoms, unstable vital signs, significant comorbidities, inability to take oral medications, or lack social support for outpatient care. Inpatient treatment often involves intravenous antibiotics, such as:

• Ceftriaxone 1-2g daily plus azithromycin 500mg daily
• A respiratory fluoroquinolone like levofloxacin 750mg daily

The higher intensity of care for hospitalized patients reflects the increased risk of respiratory failure, sepsis, and other complications that require close monitoring and immediate intervention 1.

Recent guidelines from the American Thoracic Society and Infectious Diseases Society of America support the use of oral antibiotics for outpatient treatment of CAP, and recommend that the decision to hospitalize be based on the severity of illness and risk factors for complications 1.

Overall, the decision to treat CAP as an outpatient or inpatient should be individualized based on the patient's specific needs and circumstances, with the goal of providing the most effective and safe treatment while minimizing the risk of complications and mortality.

From the FDA Drug Label

Azithromycin should not be used in patients with pneumonia who are judged to be inappropriate for oral therapy because of moderate to severe illness or risk factors such as any of the following: patients with cystic fibrosis, patients with nosocomially acquired infections, patients with known or suspected bacteremia, patients requiring hospitalization, elderly or debilitated patients, or patients with significant underlying health problems that may compromise their ability to respond to their illness (including immunodeficiency or functional asplenia).

The decision to treat community-acquired pneumonia (CAP) as an outpatient or inpatient is determined by the presence of moderate to severe illness or risk factors such as:

• Cystic fibrosis
• Nosocomially acquired infections
• Known or suspected bacteremia
• Need for hospitalization
• Elderly or debilitated patients
• Significant underlying health problems (including immunodeficiency or functional asplenia) 2

From the Research

Determining Outpatient vs Inpatient Treatment for CAP

The decision to treat community-acquired pneumonia (CAP) on an outpatient or inpatient basis depends on several factors, including the severity of the disease, the patient's overall health, and the presence of certain risk factors.

• The severity of CAP can be assessed using various scoring systems, such as the Pneumonia Patient Outcomes Research Team (PORT) score 3.
• Patients with mild to moderate CAP may be treated as outpatients with oral antibiotics, such as amoxicillin or azithromycin 4, 5.
• In contrast, patients with severe CAP or those who require hospitalization may be treated with intravenous antibiotics, such as penicillin or a fluoroquinolone 6, 7.
• The choice of antibiotic regimen may also depend on the presence of certain risk factors, such as macrolide resistance 6.
• Combination therapy with a beta-lactam plus a macrolide or doxycycline, or monotherapy with a respiratory quinolone, may be considered for hospitalized patients with CAP 7.

Factors Influencing Treatment Decision

Several factors can influence the decision to treat CAP on an outpatient or inpatient basis, including:

• The patient's age and underlying health status 3, 5
• The severity of the disease, as assessed by scoring systems such as the PORT score 3
• The presence of certain risk factors, such as macrolide resistance 6
• The availability of social support and the patient's ability to adhere to treatment 5

Antibiotic Regimens

Various antibiotic regimens may be used to treat CAP, depending on the severity of the disease and the presence of certain risk factors.

• Oral antibiotics, such as amoxicillin or azithromycin, may be used to treat mild to moderate CAP 4, 5.
• Intravenous antibiotics, such as penicillin or a fluoroquinolone, may be used to treat severe CAP or hospitalized patients 6, 7.
• Combination therapy with a beta-lactam plus a macrolide or doxycycline, or monotherapy with a respiratory quinolone, may be considered for hospitalized patients with CAP 7.