Table 1.
Clinical and Pathological Features of Eosinophilic Airway Disorders
| Classic Asthma | CVA | NAEB | AC | |
|---|---|---|---|---|
| Symptoms | Cough, SOB, wheeze | Cough only | Cough (often with upper airway symptoms) | Cough only |
| Atopy* | 60-80% | 40-80% | 20-70% | 40-50% |
| Variable airflow limitation | + | ± | — | — |
| AHR | + | + | — | — |
| Cough hypersensitivity | —~↑ | —~↑ | ↑ | ↑ |
| Response to bronchodilator | + | + | unknown | — |
| Response to corticosteroid | + | + | + | + |
| Response to H1 antagonists | ± | ± | unknown | + |
| Rapid decline of lung function | + | ± | ± | — |
| Progression to classic asthma | NA | 30% | 10% | rare |
| Sputum eos↑(>3%) | usually | usually | always (by definition) | usually |
| Exhaled NO | ↑ | ↑ | ↑ | → |
| Submucosal eos | ↑ | ↑ | ↑ | ↑ |
| BAL eos | ↑ | ↑ | ↑ | → |
| Mast cells in ASM | ↑ | → | → | unknown |
| Subepithelial thickening | + | + | + | unknown |
| Vascular proliferation | + | + | + | unknown |
*
Defined by the presence of at least one positive serum specific IgE or skin test response to common aeroallergens.