Mucopolysaccharidosis (MPS) is a group of metabolic disorders due to the lack of lysosomal enzymes that are needed to degrade glycosaminoglycans. This is characterized by the accumulation of glycosaminoglycosides (GAGs) in many types of body tissues, including the eyes .MPS is divided into different types of clinical symptoms and includes a range of phenotypes. Mucopolysaccharidoses type I (MPS I) due to the absence or insufficient of the α-L-iduronidase enzyme. MPSI classified into three types of clinical features and severity; Hurler (MPS IH), Scheie (MPS IS), and Hurler-Scheie (MPS IH-S). MPS IH is the most severe type. MPS IS has milder systemic and ophthalmic manifestations, and MPS IH / S has an intermediate phenotype. The MPS manifestations include skeletal, cardiac and respiratory problems. MPS IH; Hurler syndrome presents with coarse facial features and respiratory disease in early life . ophthalmologic examinations may detect associated corneal opacification. MPS eye manifestations include corneal clouding, retinopathy, glaucoma, and optic nerve abnormalities that vary in severity in different subtypes.

We reported a case of MPSI in A 2 years old boy referred for evaluation of bilateral corneal opacities noticed by the parents. The visual acuity was fixed and follow in both eyes. RAPD was negative, and IOP with tonopen was 12mm in the right eye and 13mm in the left eye. The fundoscopic examination was normal. The facial dysmorphism and skeletal abnormalities also were seen in this case.

According to the findings from clinical history, physical examination and imaging results; MPS I was diagnosed for the patient.

Modern treatments include enzyme replacement (ERT) and bone marrow transplantation (BMT) in MPS. These treatments provide a longer and better quality of life for many patients. Patients with MPS require regular ophthalmologic examination for the diagnosis, monitoring, and treatment of eye complications.