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Prevalence of this rare corneal dystrophy is unknown. Males are affected more severely than females.

Affected males are born with clouding ranging from a diffuse haze to a ground-glass, milky appearance, which commonly causes blurred vision, and possible nystagmus. Female patients are asymptomatic but have crater-like endothelial abnormalities. The condition is progressive in males and non-progressive in females. In advanced cases, a subepithelial band keratopathy associated with endothelial changes that resemble moon craters is observed.

XECD has been mapped to the long arm of the X-chromosome (Xq25) but the causative gene has not been identified.

Light microscopy reveals focal discontinuities and degenerative changes in the corneal endothelial cells which underlie the crater-like changes seen clinically. Descemet membrane is irregularly thickened with small pits and excavations. The corneal epithelium and Bowman zone may be irregularly thinned.

Transmission is X-linked recessive.

A penetrating keratoplasty may be indicated in males if corneal opacification impairs vision significantly. Procedures for repairing the posterior surface of the cornea, such as a deep lamellar endothelial keratoplasty (DLEK), Descemet stripping endothelial keratoplasty (DSEK), or Descemet stripping automated endothelial keratoplasty (DSAEK) are technically difficult in young children.