Abstract
Purpose: :
Keratoconus (Kc) is a noninflammatory disease and has been diagnosed in all races. In previous studies, family history has been reported in 6% to 8% of patients with Kc. An autosomal recessive inheritance model for Kc has been supported in the literature. Most of the published data in the literature have suggested that the familial Kc cases are due to autosomal dominant inheritance with incomplete penetrance or variable expression. The aim of this study is to investigate the prevalence of Kc in different regions of Saudi Arabia.
Methods: :
A retrospective medical records (MR) review was conducted of all referred patients with the diagnosis of Kc from January 1, 1999 to December 31, 2006 to a tertiary ophthalmic referral institution, King Khaled Eye Specialist Hospital (KKESH), Riyadh, Saudi Arabia. Each patient’s MR was reviewed and information collected included age, sex and the region from where the patient was referred. Referred Kc cases were classified into the main five regions of Saudi Arabia (Central, Eastern, Western, Northern and Southern).
Results: :
A total number of 1016 (522/51.38% males and 494/48.62% females) referred charts with the diagnosis of Kc were reviewed. Age of referred patients ranged between 15 to 55 years (Avg.: 24 years). The Central and the Southern regions had the higher number (38.09% and 37.5% respectively) where the Northern, Western and Eastern regions had the lower number of referred cases (10.14%, 8.86% and 5.41% respectively). Eastern and Western regions showed a higher total number, of males than females while other regions showed no significant differences between the total number of males and females among referred cases.
Conclusions: :
The most leading cause for corneal transplantation in Western countries is sporadic Kc and recent retrospective study at KKESH revealed that Kc is the most common cause for keratoplasty in the last 2 decades. This study found an even distribution of Kc between the sexes. The Kc incidence had a distinct geographic distribution with the disease concentrated in 2 (76%) of the 5 regions into which Saudi Arabia was divided. The high incidence of Kc in the Central and Southern regions correlates with the population distribution in Saudi Arabia but may also be explained by a high incidence of a genetic variant of Kc which may be linked to parental consanguinity.