Hunter Syndrome and Bullʼs Eye Maculopathy

Background

Mucopolysaccharidoses (MPSs) refer to a heterogeneous group of lysosomal storage disorders affecting the breakdown of glycosaminoglycans (GAGs), polysaccharide compounds involved in cell signaling and other biochemical processes [1]. The diseases, caused by genetic defects, result in multiorgan intra- and extracellular accumulation of the mentioned GAGs [2]. MPSs are classified into 7 types and 13 subtypes. MPS type II, also called Hunter syndrome, is an X-linked recessive disease with a deficiency in the lysosomal enzyme Iduronate-2-sulphatase, resulting in pathological storage of dermatan and heparan sulphate. Clinically, most organ systems are affected to a certain degree [3]. Cardiological and respiratory failure are the most common cause of death, which occurs at adolescence in severe forms [4].

Ophthalmological manifestations are common in MPSs and may help establish the diagnosis at an early stage, which would essentially improve patient outcomes. Ocular features of Hunter syndrome include exophthalmos, hypertelorism, retinopathy, and optic nerve abnormalities [5]. Here, we report the findings in a patient with Hunter syndrome.

Publication History

Received: 25 October 2023

Accepted: 03 January 2024

Article published online:
23 April 2024

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