Retinal and choroidal thickness in paediatric patients with hypoalbuminaemia caused by nephrotic syndrome

BACKGROUND: A study was conducted to evaluate the choroidal thickness (CT) and retinal thickness (RT) in paediatric patients with hypoalbuminaemia caused by nephrotic syndrome (NS). We also studied the correlation between the subfoveal choroidal thickness (SFCT) and serum protein concentration. METHODS: This was a cross-sectional study. Fifty-one paediatric patients with hypoalbuminaemia caused by NS and 41 normal subjects were included in the study. Enhanced depth imaging optical coherence tomography (EDI-OCT) was performed to measure the RT and CT. The RT and CT were measured manually at intervals of 0.5 mm along a horizontal line through the macular fovea between 2.5 mm nasal and 2.5 mm temporal to the fovea. Clinical data including measurements of serum proteins were obtained. RESULTS: The mean RTs at the T2.5, T2, N1.5, N2, and N2.5 locations and the average macular horizontal RT were slightly greater in the NS group than those in the control group. The mean CTs at all locations were significantly greater in the NS group than those in the control group; the difference was most significant at the fovea (373.8 ± 74.9 μm vs. 280.2 ± 57.1; p < 0.001). The SFCT in patients with NS was correlated with age (r = − 0.307, p = 0.003), body height (r = − 0.320, p = 0.022), body weight (r = − 0.343, p = 0.014), axial length (AL, r = − 0.237, p = 0.023), total protein (TP, r = − 0.302, p = 0.031), albumin (ALB, r = − 0.285, p = 0.042), prealbumin (PA, r = − 0.303, p = 0.033) and 24-h urine volume (UV, r = − 0.298, p = 0.034). Multiple linear regression analysis showed that the TP concentration and body weight had the highest correlation with the SFCT (R(2) = 0.220, p < 0.05). CONCLUSIONS: The macular RT is slightly increased and the macular CT is significantly increased in paediatric patients with hypoalbuminaemia caused by NS, indicating fluid accumulation in the retina and choroid. There is a negative correlation between the SFCT and serum TP concentration. Thus, the serum TP concentration is an important indicator of CT in patients with hypoalbuminaemia.