Crohn`s disease. Increasing trend in Saudi Arabia.

We attempted, through systematic review to explore the epidemiology and risk factors of Crohn's disease (CD) with special attention to the Kingdom of Saudi Arabia (KSA). We selected articles that contained population-based, epidemiological, and clinical character studies of CD. We collected data concerned with the prevalence, demographic features, and the possible etiology of CD that might explain its emergence in KSA.