Congenital macular scars in siblings from CLDN19 mutations.

We report 2 consecutive siblings who presented with unilateral and bilateral macular scars, respectively (initially presumed in the older sibling to be from congenital toxoplasmosis), who also developed chronic kidney disease. Both underwent genetic testing and were positive for a mutation in CLDN19, confirming the diagnosis of familial hypomagnesemia with hypercalciuria and nephrocalcinosis with severe ocular involvement. One of our patients had the unique finding of mild foveal hypoplasia, which is not typically associated with CLDN19 mutations.