Epidemiology and composition of nephrolithiasis in a Lebanese tertiary care center: A descriptive study

Nephrolithiasis is a common affliction with a prevalence of 12% in men and 7% in women. The incidence rate diverges with geographic location. Arab countries report high nephrolithiasis prevalence rates, with Saudi Arabia being the highest (20.1%). To date, there is little knowledge about the demographics and composition of stones in Lebanon.

A retrospective chart review was performed on stone composition at the American University of Beirut Medical Center, between 2005 and 2018. Patients' demographics and stone characteristics were obtained from electronic medical records. Analysis of frequencies and Chi-square test were adopted for potential risk factor correlations by the Statistical Package for the Social Sciences (SPSS).

A total of 626 stone analyses were performed. Male patients predominated (69%). The mean age was 46.58 ± 16.5 years, and mean body mass index was 28.63 ± 5.6, for both sexes. Calcium oxalate was the most predominant stone in both sexes (70%). Uric acid stones followed (~16%), and calcium oxalate phosphate stones were the third most common (5%). Incidence of kidney stones peaks in the summer, with 11.86% presenting in July. Around 60% presented with flank pain to the Emergency Department, and 32% ended up with spontaneous passage of stones by medical expulsive therapies alone, with no further surgical intervention. Diabetes and hypertension were significantly correlated with stone recurrence in our cohort.

There is a significant gender disparity in stone prevalence in Lebanon. Calcium oxalate is the most common type in both sexes. Future investigations of dietary and environmental factors are recommended from our region.