High Resolution Pulmonary Computed Tomography (HRCT) in the evaluation of patients with primary antibody deficient disorders

Purpose: To determine the utility of pulmonary HRCT in the evaluation of bronchiectasis and chronic lung disease in patients with primary antibody deficiency disorders. Materials and Methods: A retrospective review of 60 patients (ages 5-50 yrs., M:F 40:20) with primary antibody deficiency disorders who underwent a total of 125 HRCT scans over a 5 year period was performed in order to describe the extent and severity of pulmonary pathology including bronchiectatic changes present. These were then correlated with various predetermined clinical factors. As well, the HRCT changes over time were correlated with the use of high dose (600-800 mg/kg/month) intravenous immunoglobulin replacement therapy. CT scans were scored by a radiologist blinded to the patients' clinical course and previous CT scans using a previously described scoring system. Results: A total of 47/125 (38%) scans were abnormal, with bronchiectasis noted as the most common abnormality detected, seen in 38 scans of 22 patients. Upper lobe sparing was noted, as only 2/22 patients demonstrated changes most severe in the upper lobes. CT scores demonstrated statistically significant correlations with (a) age at CT, (p=0.00001) (b) ≥ 3 treated pneumonias before diagnosis of immunodeficiency, (p=0.015) (c) success of therapy at establishing adequate serum IgG levels (>600 mg/deciliter) (p=0.007) and (d) FEV1 and FVC (p=0.0019). Most (83%) patients demonstrated little change in CT score over time, suggesting the efficacy of high dose intravenous replacement therapy. Deteriorating HRCT scores in five patients helped to identify those requiring more aggressive therapy, including surgical planning for lobectomy. Conclusions: HRCT is an excellent outcome measure to follow bronchiectatic disease in patients with primary antibody deficiency disorders.