ஐ.எஸ்.எஸ்.என்: 2155-9570
Augusto Magalhaes, Joana Santos-Oliveira, Ana Maria Cunha, Susana Penas, Manuel Falcao, Angela Carneiro, Elisa Leao-Teles, Esmeralda Rodrigues, Fernando Falcao-Reis
Purpose: Mucopolysaccharidosis (MPS) are a group of lysosomal storage disorders caused by inborn Glycosaminoglycans (GAG) metabolism errors. In both MPS type I and II there is an accumulation of heparan sulfate and dermatan sulfate. This work aims to describe retinal findings in patients with MPS I and MPS II. A cross-sectional case study including 2 patients with MPS I (patients 1 and 2) and 1 patient with MPS II (patient 3) was performed. A multimodal imaging was performed using color fundus photography, Spectral Domain Optical Coherence Tomography (SD-OCT) and Near-Infrared Reflectance (NIR) imaging.
Case presentation: Patient 1, with Hurler syndrome presented in the SD-OCT, an increased thickness of the hyper reflective band of the External Limiting Membrane (ELM) in the foveal area. In the parafoveal and perifoveal regions, SD-OCT displayed loss of the interdigitation, ellipsoid and myoid zones, loss of the ELM and thinning of the Outer Nuclear Layer (ONL). Patient 2, with Hurler-Sheie syndrome, presented in the SD-OCT, an increased thickness of the hyper reflective band of the ELM in the foveal area. Patient 3, with Hunter syndrome, presented bilateral pigmentary atrophic changes at the mid-peripheral retina. SD-OCT assessment revealed thickening of the hyper reflective band of the ELM in the foveal area. Beyond the parafoveal area, the ellipsoid zone band, EML and ONL were absent.
Conclusion: MPS I and II, despite involving different enzyme deficiencies and having different inheritance patterns, accumulate the same type of GAGs and present a similar pattern of retinal changes, particularly involving the outer retina.