Kidney Stones in Children and Teenagers in the Central Coast Region of Tunisia

Objective: Since 1980s, the clinical and biological characteristics of urolithiasis in Tunisian children have continuously evolved. This retrospective study defines the current status of urolithiasis among children and adolescents in Tunisia.
Methods: We retrospectively reviewed the records of 310 children and adolescents (age: 3 months - 19 years) between 2003 and 2010, holding urolithiasis. A first-line metabolic, urine and plasma work-up was performed in all patients. Physical and chemical analysis of the stones was performed respectively by stereomicroscopy and infrared spectroscopy. Statistical analysis of the results was performed with SPSS 11.0 software. The Chi-square test was used for comparison of percentages.
Findings: Our study shows a male predominance of urolithiasis with a sex ratio of 1.5. Stones were located in the upper urinary tract in 70.7% of cases. Calcium oxalate was the predominant constituent in 52.6% of stones. There was an increasing prevalence of calcium oxalate stones according to age in both genders (48.6% in infants vs 68.5% in teenagers (P<0.01)). Struvite was more frequent in patients aged 2-9 years (P<0.02) and significantly more prevalent in boys than in girls (P<0.001). Ammonium urate stones were observed in 14.2% and were more frequent in infants.  
Conclusion: Our results emphasize a high percentage of calcium oxalate stones and a low percentage of struvite stones. The persistence of urate stones reflects the particular eating habits and the infectious risk factors. The patient’s age is an important factor that must be taken into account during etiopathogenic work-up.