SummaryBackground and objectives Retinal abnormalities are common in inherited and acquired renal disease. This study determined the prevalence of retinal abnormalities in chronic kidney disease (CKD) stages 3 to 5.Design, setting, participants, & measurements One hundred fifty patients with CKD stages 3 to 5 and 150 age-and gender-matched hospital patients with CKD stages 1 to 2 underwent bilateral retinal photography. These images were reviewed for incidental abnormalities, microvascular (Wong and Mitchell classification) and diabetic retinopathy (Airlie House criteria), and macular degeneration (Seddon classification).Results Three (2%) patients with CKD stages 3 to 5 had retinal features characteristic of inherited renal disease (atrophy in Myopathy, Encephalopathy, Lactic Acidosis, Stroke-like episodes [MELAS] syndrome; and 2 with drusen in dense deposit disease). Fifty-nine (39%) patients had moderate-severe microvascular retinopathy (hemorrhages, exudates, etc.) compared with 19 (13%) with CKD stages 1 to 2. Forty-one (28%) had moderate-severe diabetic retinopathy (microaneurysms, exudates, etc.) compared with 16 (11%) with CKD stages 1 to 2. Ten (7%) had severe macular degeneration (geographic atrophy, hemorrhage, exudates, membranes) compared with one (1%) with CKD stages 1 to 2. Renal failure was an independent risk factor for microvascular retinopathy, diabetic retinopathy, and macular degeneration. Eleven (7.3%) patients with renal failure and one (0.7%) with CKD stages 1 to 2 had previously unrecognized vision-threatening retinal abnormalities that required immediate ophthalmologic attention. ConclusionsRetinal abnormalities are common in CKD stages 3 to 5, and are more severe and more likely to threaten vision than in hospital patients with CKD stages 1 to 2.

SummaryBackground and objectives Individuals with chronic kidney disease (CKD) stages 3 to 5 have an increased risk of cardiac and other vascular disease. Here we examined the association of CKD 3 to 5 with small vessel caliber.Design, setting, participants, & measurements This was a cross-sectional observational study of 126 patients with CKD stages 3 to 5 (estimated GFR [eGFR] Ͻ60 ml/min per 1.73 m 2 ) and 126 age-and gender-matched hospital patients with CKD 1 or 2. Retinal vessel diameters were measured from digital fundus images by a trained grader using a computer-assisted method and summarized as the central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE). Results ConclusionsThe microvasculature is narrowed in patients with reduced eGFR.

Background/Aims: The effects of haemodialysis on the microcirculation are poorly understood. This study examined the changes in small vessel calibre. Methods: 24 patients (including 12 males, median age 62.5 years, range 30–87) underwent digital retinal photography immediately before and after routine haemodialysis. Arteriolar and venular calibres were measured from the images by a trained grader using a highly reproducible, computer-assisted method. Results: Patients had an average 2.0 ± 0.3 litres of fluid removed with dialysis, and their mean arterial blood pressure fell by 6.8 mm Hg (CI 13.8–0.2, p = 0.06). Retinal arteriole calibre did not change (mean difference 2.3 µm, CI –1.1 to 5.7, p = 0.17) but the venules dilated (mean difference 12.7 µm, CI 7.3–18.3, p < 0.001). Calibre returned to baseline by 2 h. Venules dilated less in diabetics than non-diabetics (mean difference –6.2 µm, CI –9.6 to –2.9, p < 0.01). Retinal venular dilatation correlated positively with the volume of fluid removed per kilogramme body weight (5.9, CI 0.2–11.5, p = 0.04), and negatively with the fall in mean arterial pressure (–0.36, CI –0.72 to –0.01, p < 0.05) after adjusting for age, gender, diabetes and dyslipidaemia. Conclusion: Haemodialysis is associated with systemic venular dilatation.