Blurry Vision in Type 1 Diabetes

The development of cataracts at the onset of type-1 diabetes mellitus (T1DM) is an uncommon complication in the pediatric population (prevalence of around 1%). It most often occurs as one of the first manifestations or within 6 months of T1DM diagnosis.

Our aim is to describe two cases of adolescents with a recent diagnosis of type-1 diabetes mellitus that were diagnosed with a complication of posterior subcapsular cataracts.

Case 1

A case of an 18-year-old girl, with complaints of reduced visual acuity in both eyes, about one year after T1DM diagnosis, under intensive insulin therapy and excellent glycaemic control (HbA_1C6.1%). After ophthalmological examination, she was found to have bilateral posterior subcapsular cataracts (PSC), that were not present at the time of a routine diabetic eye screening at diagnosis.

The patient underwent cataract surgery and intraocular lens implantation with improved visual acuity.

Case 2

A case of a 17-year-old girl who complained of blurry vision six months after T1DM diagnosis, during an ophthalmological screening. Good metabolic control of diabetes was observed during this time (HbA_1C6.7%).

The patient had a unilateral PSC of the left eye. About one year after the first diagnosis she developed PSC of the right eye. She underwent cataract surgery and intraocular lens implantation with improved visual acuity.

Conclusion: Type-1 diabetic cataracts have been found to have a female preponderance, while the pathogenesis remains unclear, it seems to be related to poor metabolic control or long history of symptoms prior to diagnosis. In these cases, good metabolic control did not appear to prevent cataract formation.

Visual impairment occurring early in T1DM in pediatric age should raise a suspicion of cataracts and ophthalmologic evaluation should be prompt.

Close monitoring of the fundi for retinopathy following cataract surgery is essential, as proliferative retinopathy may develop rapidly after the surgery.