Proliferative diabetic retinopathy as the initial presenting feature of type 1 diabetes.

Summary: Type 1 diabetes mellitus (T1DM) is an autoimmune disorder caused by the destruction of the pancreatic beta cells, which produce insulin. Individuals with T1DM usually require at least 3-5 years to develop microvascular complications in comparison to people with type 2 diabetes (T2DM), who may develop complications even before the diagnosis of diabetes. We discuss a patient who presented with proliferative diabetic retinopathy subsequently diagnosed with T1DM and diabetic neuropathy following investigations. Diabetic retinopathy or other microvascular complications as the presenting feature of T1DM is rarely known or reported in the literature. A 33-year-old healthcare worker had been seen by the opticians due to 1-week history of blurred vision. The ophthalmology assessment had confirmed proliferative retinopathy in the right eye and severe non-proliferative retinopathy in the left eye with bilateral clinically significant macular oedema. His BMI was 24.9 kg/m2. The nervous system examination revealed bilateral stocking type peripheral neuropathy. The random venous glucose was 24.9 mmol/L. Plasma ketones were 0.7 mmol/L and HbA1c was 137 mmol/mol. On further evaluation, the anti-glutamic acid decarboxylase (GAD) antibody was positive, confirming the diagnosis of T1DM. He was started on aflibercept injections in both eyes, followed by panretinal photocoagulation. Subsequent nerve conduction studies confirmed the presence of symmetrical polyneuropathy. The pathogenesis of the development of microvascular complications in T1DM is multifactorial. Usually, the development of complications is seen at least a few years following the diagnosis. The occurrence of microvascular complications at presentation is rare. This makes the management challenging and extremely important in preventing the progression of the disease. Learning points: The pathogenesis of the development of microvascular complications in type 1 diabetes mellitus is multifactorial. The development of complications is seen at least a few years following the diagnosis. Occurrence of microvascular complications at presentation is rare. This makes the management challenging and extremely important to prevent the progression of the disease.