Purpose and methods: Adolescent patients with insulin-dependent diabetes mellitus (IDDM) were retrospectively analyzed for the occurrence and possible predisposing factors of diabetic cataract in a population-based series of some 600 pediatric diabetics followed up during the years 1975-1995.
Results: Six patients (1%) needed cataract surgery. At the diagnosis of cataract they were 9.1-17.5 years old, and the duration of diabetes was between 0 months and 3 years 11 months. The type of cataract was similar in all patients characterized by bilateral snowflake type cortical deposits and posterior subcapsular cataract. Four of the six patients had at least a six-month history of diabetic symptoms before the treatment was started, and five patients had ketoacidosis at initial admission to hospital. In one of the 11 operated eyes diabetic retinopathy was observed immediately after surgery. Three patients developed proliferative retinopathy within 7-10 months after the operation, after 6.3-11.8 years of diabetes.
Conclusions: The prevalence of diabetic cataract was around 1% in the pediatric diabetic population. In the pathogenesis of cataract long duration of diabetic symptoms and ketoacidosis prior to the commencement of treatment may be of significance. Good metabolic control after diagnosis did not protect for cataract. Diabetic cataract can safely be treated by modern surgical techniques, but close monitoring of the fundi for retinopathy after the operation is crucial, as proliferative retinopathy may develop rapidly after cataract surgery despite relatively short duration and acceptable metabolic control of diabetes.