It has been shown that the sera of patients with cystic fibrosis reveal more numerous and frequent antibody responses to extracellular products of strains of Staphylococcus aureus than do sera from control subjects of a similar age, time and place.
In a significant percentage of patients with cystic fibrosis multiple antibody responses were found against extracts of a Hemophilus influenzae strain. Such multiple antibodies were not seen in sera of the control group. These findings suggest that this organism may not infrequently be involved in the pathogenesis of the pulmonary lesions.
Many more patients with cystic fibrosis than controls failed to reveal antibodies against the extracellular products of a strain of group A hemolytic streptococcus. No detectable antibodies were found in any of the sera against pneumococcal type 2 polysaccharide, old tuberculin or a mouse peritoneal toxoplasma concentrate.
The potential value of this approach for the analysis of the underlying etiologic agents involved in the respiratory infections of patients with cystic fibrosis is discussed.