Antibacterial precipitins and autoantibodies in serum of patients with cystic fibrosis.

Sera from 84 patients with cystic fibrosis, 31 patients with other respiratory 
diseases and 21 control persons have been investigated for the occurrence 
of antibacterial precipitins and autoantibodies. Preciptins were studied by means of 
crossed immunoelectrophoresis, antinuclear factors by an indirect immunofluorescence technique and rheumatoid 
factors by the latex fixation slide test. A very heterogeneous antibacterial 
immune response was found in patients with cystic fibrosis, notably as 
regards Ps. aeruginosa. None of the other patients or controls had 
precipitins against this bacterium. The occurrence of precipitins against St. aureus 
and D. pneumoniae were more frequent in cystic fibrosis patients as 
compared with controls, but not as compared with other respiratory disease 
patients. No significant differences were found as regards precipitins against H. 
influenzae or the occurrence of rheumatoid factors. Antinuclear factors were more 
frequent in cystic fibrosis patients than in the other two groups 
investigated. A pronounced and heterogeneous humoral immune response against Ps. aeruginosa 
in cystic fibrosis patients chronically infected with mucoid strains of this 
bacterium was found to be correlated with poor prognosis and the 
reason for this is discussed. 