Sir.—As medical students, we all learned the "Rule of Fs" in relation to gallbladder disease, ie, its predilection for fat, fecund, females aged 40 to 50 years with a fatty food intolerance. As an adolescent medicine specialist, I have always taught that the rules for gallbladder disease in teenagers are the same: a fat, fecund female aged 15 years with fatty food problems is most at risk, but I suggest adding an extra "F" for family history of early gallbladder disease.
For this reason I was disturbed that there was no mention of family history in the review of cases of childhood gallbladder disease in the January 1991 issue of AJDC.1 I would be very interested in those data, particularly for the idiopathic cases that accounted for one fifth of the sample, and also for the pregnant teenagers.
In teenagers, it is always better, in my opinion, to