His opinion was successfully tapered to 7.5 mg on alternate days with no deterioration in symptoms or diurnal variability (Fig 1, top, A). On bronchoscopy, the airway anatomy was grossly normal. The BALF and culture findings were unremarkable. Endobronchial biopsy samples (Table 3) showed a greatly thickened basement membrane, massive smooth-muscle hypertrophy, and goblet-cell hyperplasia (Fig 2). In addition, a large submucous gland was noted, as was mucus lining the epithelium. There were only scattered eosinophils submucosal lymphocytes noted. Despite the histologic evidence for significant airway remodeling, the patient attained normal lung function at the time of discharge.
Case 2: A 12-year-old African-American girl had a long history of severe, persistent asthma beginning at 14 months. She was hospitalized numerous times, and had required intubation and mechanical ventilation three times for acute severe asthma exacerbations. Long-term prednisone was required since the age of 8 years (Table 1). On hospital admission, medications included 10 mg of prednisone administered on alternate days, high-dose inhaled glucocorticoids, and theophylline. Her evaluation is summarized in Table 2.
Serial spirometry revealed diurnal variation in FEV1 values ranging from 75 to 103% of predicted (Fig 1, center, B). A prednisone burst resulted in a significant reduction in diurnal variability. Bronchoscopy with endobronchial biopsy was performed after 2 weeks of daily prednisone. Airway anatomy was normal while the airway mucosa was markedly inflamed and friable. The BALF cell differential was abnormal, with a substantially increased percentage of neutrophils (22%; normal, 1.5 to 2.1%) and lymphocytes (28%; normal, 8.9 to 10.1%) with an accompanying reduction in the percentage of macrophages (50%; normal, 87 to 89%); no eosinophils were present. Biopsy showed a partially denuded epithelium, squamous metaplasia, goblet-cell hyperplasia, markedly thickened subbasement membrane, and a significant quantity of elastin fibrils immediately below the basement membrane (Fig 3, Table 3).