Corneal endothelial cell abnormalities in X-linked Alport syndrome

Area of Science:

• Ophthalmology
• Nephrology
• Genetics

Background:

• X-linked Alport syndrome is caused by COL4A5 mutations affecting basement membranes.
• The kidney, ear, and eye are primary targets of this genetic disorder.
• Corneal abnormalities are increasingly recognized in X-linked Alport syndrome.

Purpose of the Study:

• To investigate corneal abnormalities in individuals with X-linked Alport syndrome.
• To compare corneal microscopy findings in affected males and females with age-matched controls.

Main Methods:

• Ophthalmological examination including slit lamp and corneal endothelial specular microscopy.
• Genetic diagnosis of X-linked Alport syndrome confirmed in 8 families (6 men, 4 women).
• Statistical comparison of corneal microscopy data between patients and normal subjects using the student's t test.

Main Results:

• Recurrent corneal erosions observed in 2 men and 1 woman.
• Corneal specular microscopy revealed larger endothelial cells, fewer 6-sided cells, and reduced cell density in affected individuals (p < 0.05).
• Posterior polymorphous corneal dystrophy was rare in this cohort.

Conclusions:

• Recurrent corneal erosions are a frequent manifestation of X-linked Alport syndrome.
• Abnormal corneal endothelial cells suggest Descemet membrane involvement.
• Reduced corneal cell density parallels reduced podocyte numbers in Alport nephropathy.