[Masquerade keratitis due to hereditary corneal disorders].

Hereditary corneal disorders can show a unilateral corneal erosion for several days due to different morphological etiologies which may result in the misdiagnosis of bacterial or viral keratitis. In such a situation it is very important to examine the contralateral eye with regard to a possible corneal opacity. The slit lamp examination has to be performed with dilated pupil in direct and indirect illumination. Patient history including familial ocular problems and recurrent alternating ocular pain can be a hint for the correct diagnosis. Masquerade keratitis of hereditary corneal disorders can be distinguished in 3 main groups: (i) recurrent corneal erosion due to systemic hereditary disorders with corneal involvement; (ii) recurrent corneal erosion due to corneal dystrophies with dystrophy-specific corneal opacities; (iii) recurrent corneal erosion in childhood without dystrophy-specific corneal opacities (occurrence of dystrophy-specific corneal opacities in adults). The ocular pain which may last several days with third group of patients often occurs in the second half of night. The children's suffering is enormous and has a negative impact on the whole family. The wearing of therapeutic contact lenses during the night may considerably reduce the ocular pain.