Letter: Essential fatty acids in cystic fibrosis.

We have read with interest the report by Elliott and Robinson concerning 
the apparent beneficial effects of intravenous fat infusions in a child 
with cystic fibrosis. We question whether the increase in essential fatty 
acids brought about by soya oil can account for the favourable 
course of the disease in this patient. Our own observations confirm 
that essential fatty acids levels are often below normal in cystic 
fibrosis, but they do not correlate with the clinical condition of 
the patient. It seems unlikely that minor degrees of essential fatty 
acid deficiency would impair prostaglandin synthesis, or give rise to the 
usual clinical features of cystic fibrosis. - Our own more recent 
research in platelet aggregation, prostaglandin, and cyclic nucleotide production, makes us 
aware that simple EFA deficiency per se cannot be the origin 
of the symptoms of CF. The possibility that some other agent 
in the infusion mixture (which, for example, contains about 12% tocopherol) 
may be a contributing factor, is also under investigation. This does 
not, however, invalidate a possible therapeutic effect of EFA in the 
disease, and in particular, a partial correlation of a possible disorder 
of prostaglandin synthesis. 