Relationships among digital clubbing, disease severity, and serum prostaglandins F2alpha and E concentrations in cystic fibrosis patients.

Nine patients with cystic fibrosis but without digital clubbing (Group A) were 
matched, prospectively, by sex and approximate age to 9 cystic fibrosis 
patients with digital clubbing (Group B) and to 9 normal persons 
(control subjects). Patients in Group B had significantly (P less than 
0.05) lower clinical scores and forced vital capacity than did those 
in Group A, indicating more severe pulmonary disease in the former; 
however, other spirometer tests of pulmonary function revealed no differences between 
Groups A and B. The degree of digital clubbing had significant 
(P less than 0.05) linear relationships to forced vital capacity (r 
= -0.73) and clinical scores (r = 0.853) for Groups A 
and B. Plasma concentrations of prostaglandins F2alpha and E were significantly 
increased (P less than 0.05) in both Group A (X +/- 
SE, 0.48 +/- 0.03 and 0.87 +/- 0.10 ng per ml, 
respectively) and Group B (X +/- SE, 0.68 +/- 0.04 and 
1.81 +/- 0.16 ng per ml, respectively) compared to the control 
group (X +/- SE, 0.14 +/- 0.01 and 0.39 +/- 0.02 
ng per ml, respectively). Group B had significantly larger concentrations than 
did Group A; however, plasma concentrations of prostaglandin 15-keto-13, 14- dihydro 
metabolite were not different in Groups A and B, and were 
significantly smaller than in the control group. These studies suggest that 
the degree of digital clubbing in cystic fibrosis is related to 
the severity of the pulmonary involvement and that the prostaglandin system 
may play an important role in this disease. 