Retinal malperfusion in albuminuric Type 1 diabetes mellitus patients without clinical signs of diabetic retinopathy: a prospective pilot study

Background To report fluorescein angiography findings in a group of albuminuric Type 1 diabetes mellitus (T1DM) patients without diabetic retinopathy. Methods Fifteen albuminuric T1DM patients with normal/near normal estimated glomerular filtration rate without diabetic retinopathy underwent fluorescein angiography; presence of microaneurysms, vascular permeability changes and retinal malperfusion were evaluated. Results Fluorescein angiography revealed microaneurysms, blood-retinal barrier breakdown and retinal ischemia in 10 (67%) and 11 (73%); 8 (53%) and 9 (60%); 2 (13%) and 5 (33%) of patients at baseline and follow up, respectively. Follow up time averaged 24.6 months, minimum follow up time was 20 months. Patients who presented retinal malperfusion had higher HbA1C and lower estimated glomerular filtration rate. Conclusions Most albuminuric T1DM patients with a normal fundus exam had angiographic signs of diabetic retinopathy, some presenting retinal malperfusion. Retinal changes may be found with more sensitive testing in these patients, especially with impaired estimated glomerular filtration rate, even if the fundus exam is normal, and fluorescein angiography should be considered. These findings point to a homogenous presentation of the diabetic microangiopathies.