Science and Education Publishing American Journal of Medical Case Reports 2374-216X 3 12 2015 12 16 Concomitant Ceftriaxone-induced Nephrolithiasis and Biliary Pseudolithiasis in a Small Toddler 422 424 EN Gimiga Nicoleta Miron Ingrith Mocanu Adriana Department of Pediatrics, 'Gr. T. Popa' University of Medicine and Pharmacy, Iasi, Romania Olaru Claudia Stanca Raluca Diaconescu Smaranda AJMCR201531211 10.12691/ajmcr-3-12-11 2015 7 12 2015 9 28 2015 12 14 Ceftriaxone is commonly used in pediatric practice and has been associated to biliary pseudolithiasis, nephrolithiasis and bladder sludge. We report a case of a 5-month old male toddler previously treated with high ceftriaxone doses for interstitial pneumonia; after one week an improvement of respiratory symptoms was noticed but extreme agitation and excessive crying occurred. He eliminated small white crystals that were found in the diaper and were proven to be constituted from calcium carbonate; abdominal ultrasound showed also a hyperechoic image of 4 mm in the gallbladder. Laboratory data were within normal rangers except a slight increase of the urinary calcium and calcium/creatinine ratio. The patient didn't have any risk factor for ceftriaxone- induced lithiasis except high dosage of the antibiotic together with idiopathic hypercalciuria. Antibiotic interruption together with hydrochlorothiazide, adequate hydration and antispasmodics led to the remission of the symptoms and disappearance of the gallbladder image within 5 weeks. Ceftriaxone treatments should be routinely monitored by ultrasounds for the urinary and biliary system; appropriate dosage and administration with an adequate hydration are required.