The inheritance of the autosomal recessive type of gyrate atrophy of the choroid and retina seems well documented (Botermans, I 972), but the aetiology of the disease is still unknown.Animal experiments and some disturbances of lipid, carbohydrate, and protein metabolism connected with chorio-retinal degenerations in man support the possibility of an enzymatic disorder as an aetiological factor of these diseases (Franceschetti, Fran §ois, and Babel, I963; FranSois, I964).The present author recently diagnosed gyrate atrophy of the choroid and retina in an 8-year-old boy in whom an enlarged lysine-ornithine spot was found on the urine highvoltage electrophorogram in routine examination of urinary amino-acids. Further studies identified that the spot was ornithine. The plasma ornithine concentration was more than ten times higher than normal, although normal amounts of the other plasma aminoacids were present. A constant correlation between hyperornithinaemia and gyrate atrophy of the choroid and retina was then detected in nine other patients (Simell and Takki, I973).The purpose of this paper is to describe the different forms of gyrate atrophy found in a total of fifteen patients and to discuss the correlation of fundus changes with hyperornithinaemia.
MaterialAn examination of case histories from I950 to 1972, with clinical diagnosis of any primary chorioretinal degeneration, revealed some thirty cases in which gyrate atrophy was suspected. Among them eleven cases of gyrate atrophy of the choroid and retina at different stages were found. Three additional cases were found among relatives of one patient and one further case was referred to the author. The total number of cases with gyrate atrophy of the choroid and retina described in this paper is thus fifteen, nine of which were included in our previous paper (Simell and Takki, I973). The characteristics of the patients are shown in Table I (overleaf). Among the ten families there were four sisters (Patients 6 and 9-I I) and two pairs of sisters (Patients 3, 5, and I 2-I3) and one of these was the first cousin of another patient (Patient 4).There were twenty intact and ten aphakic eyes, four of which were treated because of open-angle glaucoma. One eye was in postoperative phthisis after a cataract operation (Table II, overleaf).