Pseudoinflammatory fundus dystrophy: a follow-up study.

We have performed a reinvestigation of a family with a presumably autosomal recessive form of pseudoinflammatory dystrophy, which we have followed for 25 years. The symptoms in this family are subretinal haemorrhages appearing at age 13-40 years in the central fundus, resulting in glial cicatrication in the outer retinal layers, progressive myopia and profound choroidal atrophy in the advanced stages of the disease. During the follow-up study, a new affected subject was found in the younger generation, and two collateral cases, who had earlier been considered as probably affected subjects, were now considered to have other fundus affections. The new case is the daughter of an affected female. The possibilities of an autosomal dominant mode of inheritance or pseudodominance are discussed. Extended genealogical studies showed that the parents of all the affected subjects, with the exception of the new case, have their origin in an area which was isolated until recently and have several common ancestors within the last 8-10 generations. Recessive inheritance also logically explains the appearance of the disease in so few other members in the vertical line of the family. To this fundus dystrophy, the rule of Lenz seems to apply: If more or less the same phenotype can be caused by both a recessive and a dominant gene, the phenotype caused by the recessive gene is generally manifested earlier and by more severe symptoms.