What is the inpatient treatment for pneumonitis?

Inpatient Treatment for Pneumonitis

Inpatient treatment for pneumonitis requires hospitalization for grade 3 or higher pneumonitis, with drug withdrawal as the mainstay of treatment, followed by intravenous corticosteroids and additional immunosuppression for recalcitrant cases. 1

Severity Assessment and Admission Criteria

Pneumonitis severity should be assessed to determine appropriate management:

• Grade 1 (mild): Asymptomatic or minimal symptoms; radiographic changes only
• Grade 2 (moderate): Symptomatic; affecting activities of daily living
• Grade 3 (severe): Severe symptoms; limiting self-care; oxygen indicated
• Grade 4 (life-threatening): Life-threatening respiratory compromise
• Grade 5: Death

Hospitalization is required for:

• Grade 3 or higher pneumonitis
• Patients with significant hypoxemia (SaO2 <92% or PaO2 <8 kPa)
• Bilateral or multilobe involvement on chest radiograph 1

Inpatient Management Protocol

Immediate Interventions

1. Drug Withdrawal

   • Discontinue the causative agent (e.g., immune checkpoint inhibitors, bleomycin) 1, 2
   • This is the first and most critical step for all grades of pneumonitis

2. Oxygen Therapy

   • Provide appropriate oxygen therapy with monitoring of oxygen saturations
   • Aim to maintain PaO2 >8 kPa and SaO2 >92% 1
   • High concentrations of oxygen can safely be given in uncomplicated pneumonitis
   • For patients with pre-existing COPD, guide oxygen therapy with repeated arterial blood gas measurements 1

3. Corticosteroid Therapy

   • For grade 2 or higher pneumonitis, initiate intravenous corticosteroids 1
   • Typical regimen: methylprednisolone 1-2 mg/kg/day or equivalent
   • Maintain high-dose steroids until clinical improvement is noted
   • Taper steroids slowly over 4-6 weeks minimum to prevent recrudescence 1
   • Rapid steroid tapering has been associated with symptom recurrence 2

Monitoring and Supportive Care

1. Regular Assessment

   • Monitor temperature, respiratory rate, pulse, blood pressure, mental status, oxygen saturation, and inspired oxygen concentration at least twice daily 1
   • More frequent monitoring for severe pneumonitis or patients requiring regular oxygen therapy

2. Fluid Management

   • Assess for volume depletion and provide intravenous fluids as needed 1

3. Nutritional Support

   • Provide nutritional support, especially in prolonged illness 1

4. Repeat Imaging

   • CRP level should be remeasured and chest radiograph repeated in patients who are not progressing satisfactorily 1
   • CT imaging is more reliable than chest radiographs in identifying pneumonitis changes 1

Management of Refractory Cases

For patients who do not respond to corticosteroids:

1. Additional Immunosuppression

   • Add infliximab (5 mg/kg) for steroid-refractory cases 1
   • Cyclophosphamide may be considered as an alternative immunosuppressant 1

2. Bronchoscopy with BAL

   • Consider bronchoscopy with bronchoalveolar lavage to exclude infectious etiologies 1
   • This is particularly important in patients not responding to initial therapy

3. ICU Transfer

   • Consider ICU transfer for patients with worsening respiratory status despite treatment
   • Non-invasive ventilation can reduce the risk of death, endotracheal intubation, and complications in appropriate patients 3

Special Considerations

Immune Checkpoint Inhibitor-Induced Pneumonitis

• Appears earlier in NSCLC (median 2.1 months) versus melanoma (median 5.2 months) 1
• May be accompanied by other immune-related adverse events affecting other organ systems
• Patients with pre-existing lung disease (COPD, pulmonary fibrosis) present diagnostic challenges 1
• Complete resolution may allow cautious rechallenge of immune checkpoint inhibitors in select cases 4

Bleomycin-Induced Pneumonitis

• Can occur at cumulative doses as low as 136 units
• Prolonged corticosteroid therapy over many months is often required
• Tapering of steroids may lead to recurrence of symptoms and radiographic infiltrates 2

Pitfalls and Caveats

1. Delayed Recognition: Failure to recognize and treat pneumonitis promptly can lead to poor outcomes, especially in patients with pre-existing lung disease 1

2. Inadequate Steroid Duration: Recrudescence of symptoms commonly occurs with rapid steroid tapering; a minimum 4-6 week taper is recommended 1

3. Missed Infections: Always consider and rule out infectious etiologies, particularly in immunocompromised patients

4. Incomplete Drug Withdrawal: Continuing the causative agent, even at reduced doses, may prevent resolution

5. Inadequate Monitoring: Regular reassessment of severity during treatment is mandatory to adjust management appropriately 1