What is the recommended scoring system and treatment approach for an adult patient with pneumonia, considering factors such as confusion, urea level, respiratory rate, blood pressure, and age?

Pneumonia Severity Scoring and Treatment Approach

Recommended Scoring System

For initial site-of-care decisions in adults with community-acquired pneumonia, use CURB-65 as the primary severity assessment tool, which assigns one point each for: Confusion, Urea >7 mmol/L (or BUN >19 mg/dL), Respiratory rate ≥30/min, Blood pressure (systolic <90 mmHg or diastolic ≤60 mmHg), and Age ≥65 years. 1

Why CURB-65 Over PSI

• CURB-65 is preferred due to its simplicity and ease of use compared to the more complex Pneumonia Severity Index (PSI), which requires 20 variables including laboratory and radiographic data 1, 2
• CURB-65 focuses on illness severity rather than just mortality prediction, making it more clinically actionable 1, 3
• The score can be calculated rapidly at bedside with only one laboratory test (urea/BUN) 1, 3

Risk Stratification and Mortality Rates

The mortality risk increases directly with CURB-65 score 1, 2:

• Score 0: 0.7% mortality - outpatient treatment
• Score 1: 2.1% mortality - outpatient treatment
• Score 2: 9.2% mortality - hospitalization or intensive home care
• Score 3: 14.5% mortality - hospital admission with ICU assessment
• Score 4: 40% mortality - hospital admission with ICU assessment
• Score 5: 57% mortality - hospital admission with ICU assessment

Treatment Algorithm by CURB-65 Score

CURB-65 Score 0-1: Outpatient Treatment

For healthy adults without comorbidities:

• Amoxicillin 1g three times daily (first-line) 1, 2
• Doxycycline 100mg twice daily (alternative) 1, 2
• Macrolide (azithromycin 500mg day 1, then 250mg daily) only if local pneumococcal macrolide resistance <25% 1

For adults with comorbidities (chronic heart/lung/liver/renal disease, diabetes, alcoholism, malignancy, asplenia):

Combination therapy:

• Amoxicillin/clavulanate (500/125mg three times daily OR 875/125mg twice daily) PLUS macrolide or doxycycline 1, 2

OR Monotherapy:

• Respiratory fluoroquinolone (levofloxacin 750mg daily, moxifloxacin 400mg daily, or gemifloxacin 320mg daily) 1, 2

CURB-65 Score 2: Hospitalization or Intensive Home Care

Patients with score of 2 face 9.2% mortality and require more intensive treatment - either hospitalization or intensive in-home health services where available 1, 2, 3

• These patients have clinically important physiologic derangements requiring active intervention 1
• Consider short hospital stay or supervised outpatient treatment 1

CURB-65 Score ≥3: Hospital Admission with ICU Assessment

Mandatory hospital admission with prompt evaluation for ICU care 1, 2, 3

• Score 3: 14.5% mortality
• Score 4-5: 40-57% mortality 1, 2

ICU Admission Criteria: Use IDSA/ATS Severe CAP Criteria

Critical limitation: CURB-65 alone performs poorly for ICU triage decisions. Instead, use the 2007 IDSA/ATS severe CAP criteria 1, 3, 4

Major Criteria (Either One Requires ICU Admission):

• Septic shock requiring vasopressors 1, 3
• Acute respiratory failure requiring intubation and mechanical ventilation 1, 3

Minor Criteria (≥3 Requires ICU or High-Level Monitoring):

• Respiratory rate ≥30/min 3
• PaO2/FiO2 ratio ≤250 3
• Multilobar infiltrates 3
• Confusion/disorientation 3
• Uremia 3
• Leukopenia 3
• Thrombocytopenia 3
• Hypothermia 3
• Hypotension requiring aggressive fluid resuscitation 3

Rationale: Patients transferred to ICU after initial ward admission experience higher mortality than those directly admitted to ICU from the emergency department 1

Critical Pitfalls and Caveats

When CURB-65 Underestimates Severity:

Young patients (<65 years) with severe respiratory failure may have low scores despite significant physiologic derangement because age is heavily weighted 1, 3

Additional factors requiring hospitalization despite low CURB-65 scores 1, 2:

• Inability to maintain oral intake or take medications reliably
• Hypoxemia (oxygen saturation <90% or PaO2 <60 mmHg)
• Homelessness or lack of social support/caregiver
• Severe psychiatric illness or injection drug abuse
• Exacerbation of underlying diseases (COPD, heart failure, diabetes)
• Pleural effusion
• Failure of prior adequate outpatient antibiotic therapy

When CURB-65 Overestimates Severity:

Elderly patients with multiple stable comorbidities may have falsely elevated scores without true severity 3

Essential Clinical Judgment Points

CURB-65 must be supplemented with physician assessment of subjective factors - never use the score as the sole determinant for admission decisions 1, 2

• Dynamic assessment over several hours may be more accurate than a single point-in-time score 1
• Consider implementing CURB-65 as part of a systematic pneumonia care bundle including pulse oximetry and point-of-care lactate 2, 3

Monitoring and Follow-Up

• Clinical improvement should be expected within 3 days - patients should contact their physician if no improvement occurs 2, 3
• Reassess for treatment failure, resistant organisms, or complications if fever persists beyond 72 hours 2