New research indicates that a 7-day course of ceftriaxone increases the risk of small asymptomatic renal stones in children.

Ceftriaxone, a third-generation cephalosporin, is eliminated through the kidneys as well as through the biliary system. Although biliary sludge, or pseudolithiasis, is a known side effect of the drug, the effects on renal stone formation are less well understood.

Case reports have tied ceftriaxone to nephrolithiasis, but the current study is the first to prospectively investigate this link, Dr. Ahmet Karadag, from Faith University in Ankara, Turkey, and colleagues note.

The study, which is reported in the Archives of Disease in Childhood for November, involved 51 children who were treated with ceftriaxone for various infections. Of the subjects, 24 had severe infections requiring hospitalization and 27 had milder infections.

In the severe infection group, ceftriaxone was given at a total dose of 100 mg/kg/day divided into two intravenous doses. In the milder infection group, the drug was given intramuscularly once daily at a dose of 50 mg/kg/day.

Renal function tests and calcium levels were normal in all subjects before and after treatment, the authors point out.

Post-treatment ultrasound testing revealed renal stones in four (7.8%) of the children. However, all of the stones were asymptomatic and were typically 2 mm in diameter or smaller. No significant predictors of kidney stone formation were identified.

In all but one of the cases, the stones disappeared spontaneously. In the remaining case, the stones were still apparent 7 months after treatment.

Despite the apparent benign course of the stones in the current study, the authors note that "it is particularly important to monitor patients on high-dose long-term ceftriaxone treatment with ultrasonography and renal function testing, as these individuals may be at greater risk for large stones and renal damage."

Arch Dis Child 2004;89:1069-1072.

When NIH Halted A Major Study, Citing Risks From A
Common Painkiller, The Media
Played The News Big. That Was Just Part Of The Problem

Steven Woloshin, Lisa M. Schwartz and H. Gilbert Welch
The Washington Post, February 01, 2005
Section: Health