The term biliary pseudolithiasis was coined by Schaad (1988) to describe the appearance of gallbladder sludge following treatment with ceftriaxone. After cessation of the drug the condition resolves, hence the term “pseudolithiasis.” The third generation cephalosporin, cefatriaxone, is a very potent, broad spectrum antibiotic indicated in meningitis, osteomyelitis, pyelonephritis,
Lyme disease and many other severe infectious diseases. Up to 46% of those receiving this antibiotic develop gallbladder sludge. Most are asymptomatic, but a small proportion may develop right upper quadrant pain, nausea, vomiting and even cholecystitis. Ultrasonography may demonstrate many, small, echogenic particles within the gallbladder, as well as larger echogenic foci casting acoustic shadows. However, it can not differentiate these pseudostones from real stones. There are reports of surgical intervention in such cases. 2 boys, aged 5 and 10 years, respectively, treated with ceftriaxone for meningitis are presented. Both developed symptoms during treatment and in both gallbladder sludge was identified by ultrasonography. In 1 intraluminal gallbladder findings were identical with the appearance of surgical stones. Follow-up ultrasonography after the drug was stopped showed no evidence of pseudostones in either case. Awareness of this phenomena might save many unnecessary operations.