Ceftriaxone是一常用的廣效第三代頭孢子素，它的抗菌範圍包括了格蘭氏陽性及陰性菌；Ceftriaxone的耐受性佳，高劑量( > 2g/day)下會引起膽汁淤泥(biliary sludge) ，但通常發生於兒童。本案例為一60歲女性病人因慢性骨髓炎使用高劑量ceftriaxone 治療；在治療第9天後，發現在ceftriaxone施打完後尿液呈混濁現象，後續抽血檢驗發現病人的血鈣及尿鈣均偏高，因ceftriaxone會以原型由尿液排出，所以初步懷疑是ceftriaxone-calcium complex 造成之尿結晶；且後續的腹部超音波亦發現病人有膽囊淤泥現象。而在將ceftriaxone改為口服ceftibuten 200mg一天二次治療，病人尿液即不再呈混濁現象。

Ceftriaxone is a commonly used third-generation cephalosporin that has antimicrobial activity against many gram-positive and gram-negative organisms. Generally ceftriaxone is a safe antibiotic; however, symptomatic biliary sludge has been reported in rare instances, most of which have involved children. This is a case of 60-year-old woman with chronic osteomyolitis who was treated with high dose ceftriaxone. After 9 days of therapy, the patient reported the painless passage of gravel on micturition. Follow-up the urine and serum sample revealed the hypercalciuria and hypercalcemia in this patient. We suspected the interaction of ceftriaxone with calcium by ceftriaxone-calcium precipitates in patient’s urine. Also, the abdominal ultrasonography demonstrated biliary sludge in the gallbladder. After shift antibiotic to ceftibuten 200mg bid, the urinary precipitation was improved.