Not surprisingly, couldn't find any good studies that looked at the outcome of this patient population. The best paper I found was by Bogue et al, who retrospectively reviewed charts of 382 patients with GB stones and identified a group of patients who were incidentally found to have cholelithiasis (asymptomatic). Of the 382 patients, 50% were asymptomatic. Their mean age was 8 YO, and they had their u/s for unrelated causes, manly other abdominal pathology.
The authors reported that follow up for these asymptomatic kids was "an annual clinical and ultrasound assessment for 1 to 2 years" unless they had other pathology that necessitated longer follow up. With this strategy, their mean follow up for this patient group was 3+/- 1.7 years. During this follow up period, only 4.6% of the patients developed complications related to their stones (pancreatitis, choledocholithiasis, cholecystitis). Interestingly, they noted that 19% of GB stones eventually resolved, as demonstrated by follow up ultrasounds (when they were done).
So what does this mean? Not much when it comes to counseling parents. At best I can suggest to them that there is very little chance the stones will cause problems in the near future, but that we can not predict their behavior (or even their persistent existence) over the long run.
Reference:
Bogue C O et al. Risk factors, complications, and outcomes of gallstones in children: a single-center review. Journal of Pediatric Gastroenterology and Nutrition (2010) 50:p303
