Figure.

Plain abdominal computed tomography (CT) and ultrasonography images of the cases involving patients with central nervous system infections who were treated with intravenous ceftriaxone (CTRX). Case 1: Some tiny gallstones were present before the initiation of CTRX therapy (A, arrow). The number of gallstones increased after 2 weeks of CTRX treatment (B, arrow). The number of gallstones further increased, and the gallbladder was filled with biliary sludge after 10 weeks of CTRX treatment (C, arrow). The gallstones and biliary sludge resolved at 2 weeks after the discontinuation of CTRX (D, arrow). Case 2: Neither gallstones nor biliary sludge was present before the initiation of CTRX treatment (E). Numerous gallstones with biliary sludge appeared after 7 weeks of CTRX treatment (F, arrow). Abdominal ultrasonography performed at 2 weeks after the discontinuation of treatment showed a reduction in the number of gallstones and the amount of sludge (G). Case 3: Neither gallstones nor biliary sludge was present before the initiation of CTRX therapy (H). The faint appearance of biliary sludge occurred after 2 weeks of CTRX treatment (I, arrowhead). In addition to the presence of condensed biliary sludge at the bottom of the gallbladder (J, arrow), bilateral nephrolithiasis (J, arrowhead) appeared after 5 weeks of CTRX treatment. The biliary sludge and nephrolithiasis resolved at 5 weeks after the discontinuation of CTRX (K, arrow). Case 4: Neither gallstones nor biliary sludge was present before the initiation of CTRX treatment (L). Abdominal ultrasonography performed after 10 days of CTRX treatment (M) and after discontinuation of CTRX treatment (N) did not show gallstones or biliary sludge.