Severe CF Research Articles

Granulocyte Chemiluminescence in Adolescent Patients with Cystic Fibrosis1,2

The granulocyte chemiluminescence (CL) response is the result of activating its cellular "respiratory burst" and oxidative metabolism. The resulting light emission is an indication of intact metabolic events important in bactericidal activity. Patients with cystic fibrosis have recurrent pulmonary infections. To determine whether granulocytes from patients with CF have defective oxidative metabolism, CL was assayed in 8 patients and compared with that in normal control subjects. In CF, the peak CL response to opsonized zymosan is normal. If, however, the time required for peak light emission is compared with the NIH Clinical Score, a significant correlation is found. Granulocytes from patients with airway disease and more severe CF have a more rapid onset of the CL response. Although the clinical significance of this observation is not established, granulocytes from patients with CF appeared "primed" in their responses to a phagocytic stimulus.

ANATOMICAL DEAD SPACE (VD) AND LUNG EMPTYING IN ASTHMA AND CYSTIC FIBROSIS (CF)

Ten normal, 10 CF and 10 asthmatic children were studied to assess the contribution of lung zones emptying at different rates to curvilinearity of the maximum expiratory flow-volume (MEFV) curve. Lung volumes, MEFV curves on air and on heliumoxygen mixture and single breath nitrogen washouts were measured. Partial forced expiratory maneuvers were performed to produce flow transients exceeding maximum flow at mid-lung volumes. Normal children and those with asthma and mild CF had small or no transients and normal VD. Those with severe CF had large transients (mean 150ml.) and large VD (mean, 155% pred.), and the volume of the transients corresponded closely to that of the VD. These large transient volumes were associated with increased curvilinearity of the MEFV curve and loss of helium response; whereas asthmatics with marked curvilinearity had small transients and helium responsiveness. In severe CF, the large transients suggest sequential emptying of fast and slow compartments which influences the shape of the MEFV curve. The fast component could correspond to emptying of an enlarged VD. Any time constant inequality present in asthma and mild CF does not appear to contribute to the shape of the MEFV curve.