[Clinical and biochemical characterization of childhood urolithiasis]

OBJECTIVES

Urolithiasis is rare in children, but the incidence has increased over the past few decades. This study aims at describing the clinical and biochemical characteristics, etiology, and treatment of urolithiasis in children.

METHODS

This was a retrospective study of all children under 16 years of age seen at the Bordeaux University Children's Hospital with a diagnosis of urolithiasis. The diagnosis was confirmed either radiologically or clinically by the expulsion of the stone.

RESULTS

A total of 186 children with a diagnosis of urolithiasis between 1994 and 2012 were included. The median age at diagnosis was 7.4 years. The male-to-female ratio was 1.9. The estimated annual incidence was around 5.5/100,000 children under 15 years of age in the past 5 years. The main presenting feature was nonspecific abdominal pain (71%). Metabolic calculi accounted for 48% of the patients with idiopathic hypercalciuria as the main cause. Genetic diseases accounted for 15% of cases. The proportion of infectious calculi was estimated at 33% and decreased in the past two decades. Stone fragments were sent for analysis in 86 children, and calcium oxalate was the major component (37%), followed by calcium phosphate (33%), purine (9%), and struvite (8%). At least 26% of patients experienced recurrence of stone passage.

CONCLUSION

This retrospective study highlighted changes in characteristics of pediatric urolithiasis over time. Childhood-onset urolithiasis requires complete etiological work-up so that a metabolic cause with a high risk of recurrence does not go unrecognized.

Shopper cards data and storage practices for the investigation of an outbreak of Shiga-toxin producing Escherichia coli O157 infections

INTRODUCTION

An outbreak of shiga-toxin producing Escherichia coli infections occurred in southwest France in June 2012. The outbreak was investigated to identify the source of infection, and guide control measures.

METHODS

Confirmed outbreak cases were patients who developed bloody diarrhoea or haemolytic uremic syndrome (HUS) between 28 May and 6 July 2012, with E. coli O157 isolates showing indistinguishable patterns on pulse field gel electrophoresis (PFGE). A standardized questionnaire was administered to patients to document food consumption and other risk exposures. Their purchase was checked through their supermarket shopper card data.

RESULTS

Six patients (four with HUS and two with bloody diarrhea) were confirmed outbreak cases. Fresh ground beef burgers from one supermarket were the only common food exposure, identified by interviews and shopper card data. The PFGE profile of shiga toxin-producing E. coli O157 isolated from the suspected beef burgers was identical to those from the human cases. The suspected beef burgers were no longer on sale at the time of investigation but three patients confirmed as outbreak cases had deep-frozen some at home.

CONCLUSION

Shopper card data was particularly useful to obtain precise and reliable information on the traceability of consumed food. Despite the expired use-by date, a recall was issued for the beef burgers. This contributed to preventing other cases among consumers who had deep-frozen the beef burgers.

[Idiopathic nephrotic syndrome in children: Incidence, clinical presentation, and outcome in the county of Gironde, France]

AIMS

To estimate the incidence and describe the clinical presentation and outcome (steroid responsiveness, clinical course, complications) of idiopathic nephrotic syndrome in children in a population-based retrospective study.

METHODS

Using local registries and the hospital discharge diagnosis system from two centers, all new cases of idiopathic nephrotic syndrome were identified in Gironde (France) between January 1992 and May 2008. To estimate incidence, population-based denominators were obtained from the National Institute for Statistics and Economic Studies (INSEE). Clinical data were collected from medical charts.

RESULTS

Ninety-nine cases of idiopathic nephrotic syndrome were reported (66 boys, 18 non-Caucasians) with an incidence of 2.3/100,000 (CI, 1.8-3.0) children less than 15 years. Ninety patients (91%) had steroid-sensitive nephrotic syndrome (SSNS) and nine (9%) were steroid-resistant (SRNS). The median time to remission in SSNS was 11 days. Relapses occurred in 75 (83%) children with SSNS with a median of four relapses (range, 1-32). The cumulative relapse-free incidence was 60% at 10 years after diagnosis in SSNS and 13% of patients aged 18 years old or over still had active disease. In SSNS, the only significant factor associated with steroid dependency or use of non steroid drugs was the time to initial response to steroids greater than 14 days. Nineteen children (19%) experienced severe complications of nephrotic syndrome including 11 bacterial infections and two thromboembolic complications. Two children with SRNS, of whom one was initially steroid-responsive, developed end-stage renal failure.

CONCLUSION

The incidence and outcome of idiopathic nephrotic syndrome in Gironde are comparable to the rates found in other studies. The disease may have a long course and the time for response to steroids at disease onset is the main predictor of steroid dependency and of use of non steroid agents.