Lattice corneal dystrophy type IIIA. Clinical and histopathologic correlations
E. L. Stock, R. S. Feder, R. B. O'Grady, J. Sugar and S. I. Roth
Cornea and External Eye Disease Laboratory, Veterans Affairs Lakeside Medical Center, Chicago, Ill.
All three types of lattice corneal dystrophy are inherited and localized,
and they largely involve linear corneal amyloid deposits. We encountered
two white families with lattice corneal dystrophy which closely resembled
type III. Four generations of one family and three of another family
exhibited lattice corneal dystrophy. Because both families are from
Caccamo, Sicily, Italy, we believe it is likely that both are from a single
mutation. Thick, ropy lattice lines were seen to traverse the corneas
almost from limbus to limbus and were easily detected with direct
illumination. Histopathologic examination revealed accumulations of varying
sized amyloid deposits in the stroma and ribbons of amyloid between the
stroma and Bowman's layer typical of lattice corneal dystrophy type III. We
have named the disease in this family lattice corneal dystrophy type IIIA,
because of three differences from lattice corneal dystrophy type III: the
presence of corneal erosions, the occurrence in whites, and the autosomal
dominant inheritance pattern.