From the Guidelines
Acute exacerbation of interstitial lung disease (ILD) is diagnosed when a patient experiences a progressive increase of dyspnea, decrease of FVC or DLCO, worsening of signs of pulmonary fibrosis on computed tomography, or acute exacerbation of the disease, as suggested by the French practical guidelines for the diagnosis and management of idiopathic pulmonary fibrosis 1. The diagnostic criteria for ILD exacerbation include:
- Progressive increase of the level of dyspnea
- Progressive decrease of FVC (especially by <10% of the relative or absolute value)
- Progressive decrease of DLCO (especially by <15% of the relative or absolute value)
- Worsening of signs of pulmonary fibrosis on computed tomography
- Acute exacerbation of the disease These changes suggest worsening of IPF, and visits to a specialized centre must take place at least annually or more frequently if deterioration occurs, with 3 monthly visits alternating with visits to a specialized centre, preferably in the context of a formal or informal care network involving the treating general practitioner and the treating pulmonologist 1. The management of ILD exacerbation typically involves close monitoring and treatment of the underlying cause, with the goal of improving symptoms, slowing disease progression, and improving quality of life. Key considerations in the management of ILD exacerbation include:
- Frequent visits to a specialized centre to monitor disease progression and adjust treatment as needed
- Use of supplemental oxygen to manage hypoxemia
- Consideration of immunosuppressants or corticosteroids to reduce inflammation and slow disease progression
- Early recognition and aggressive treatment of potential triggers, such as infection or pulmonary embolism.
From the Research
ILD Exacerbation Criteria
The criteria for ILD exacerbation are not explicitly defined in the provided studies, but several factors can contribute to the exacerbation of interstitial lung disease (ILD).
- Acute exacerbation of ILD (AE-ILD) can present as acute respiratory distress in a patient with a pre-existing ILD diagnosis or as a de novo presentation of ILD, and is associated with significant morbidity and mortality 2.
- A variety of underlying triggers may result in AE-ILD, and emergency clinicians must first assess for extraneous causes of respiratory decompensation prior to diagnosing AE-ILD 2.
- For a de novo presentation of ILD, emergency physicians should also assess for possible reversible causes 2.
Management of ILD Exacerbation
The management of ILD exacerbation involves several strategies, including:
- Systemic steroids, immunosuppressants, intravenous antibiotics, supplemental oxygen, and extracorporeal membrane oxygenation in severe cases 2.
- Risk stratification using clinical and radiographic findings, and early palliative care involvement, are important in ICU care 3.
- Ventilation strategies used in acute respiratory distress syndrome might be implemented in AE-ILD 3.
Diagnostic Criteria for ILD
The diagnostic criteria for ILD are based on a combination of clinical, radiographic, and physiologic findings.
- Thoracic computed tomography is approximately 91% sensitive and 71% specific for diagnosing subtypes of ILDs such as IPF 4.
- Physiologic assessment provides important prognostic information, and a 5% decline in forced vital capacity (FVC) over 12 months is associated with an approximately 2-fold increase in mortality compared with no change in FVC 4.
- High expiratory flows, defined as forced expiratory volume in 1 s (FEV1)/FVC, FEF25, FEF25-75, FEF75, and peak expiratory flow > 95% confidence limit of normal, may be an early abnormality in patients with ILD 5.
Predictors of ILD Progression
Several factors can predict the progression of ILD, including: