Role of SD‐OCT in the follow‐up of a patient with macular edema associated with mucopoysaccharidosis type II (Hunter syndrome) undergoing idursulfase enzyme replacement therapy

Abstract

PurposePurpose: Mucopolysaccharidosis (MPS) type II (Hunter syndrome) is a variable, progressive, multisystem disorder including severe airway obstruction, cardiomyopathy, skeletal deformities and neurological problems. It is an X‐linked recessive disease caused by deficiency of the lysosomal enzyme iduronate‐2‐sulphatase, leading to accumulation of glycosaminoglycans. Several ophthalmological disorders, including corneal opacities, glaucoma and retinal degeneration, have been previously reported. This is the first case of bilateral macular edema associated with MPS II. The patient underwent idursulfase enzyme replacement therapy with good response. We point out the utility of spectral domain optical coherence tomography (SD‐OCT) in the diagnosis and follow‐up of this condition.MethodsSD‐OCT, fundus autofluorescence and retinography were used in the diagnosis and follow‐up of the visual disorder.ResultsMacular edema was successfully managed with idursulfase enzyme replacement therapy stabilizing visual loss. Central macular thickness measured by SD‐OCT decreased significantly.ConclusionIdursulfase enzyme replacement therapy seems to be a good treatment option for macular edema associated with MPS II. Furthermore, SD‐OCT played a key role in the diagnosis and follow‐up of this condition.

The Value of Case Reports in Systematic Reviews from Rare Diseases. The Example of Enzyme Replacement Therapy (ERT) in Patients with Mucopolysaccharidosis Type II (MPS-II)

“…The efficacy of ERT was explored on key outcomes (social behavior, skin lesions, central nervous system development, bone abnormalities, visual acuity) and specific situations (serious respiratory impairment, hematological disease, and physical abnormalities) that had not been considered in previous clinical studies. Additionally, case reports also proposed new therapeutic strategies to deal with immune reactions against ERT [ 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 49 ]. In accordance with previous results, we observed that most of these novelties were not assessed in subsequent clinical studies after five years from the publication of the case report [ 13 ].…”

“…(3) Effects in pebbling skin lesions [26,27] Case report (Srinivas SM et al, 2017) [51] No clinical study after 8 years (4) Effects in hyperactivity, aggressive behavior, language functioning, and social interaction [28] No clinical study after 7 years No clinical study after 7 years [30,31] Case report Scarpa et al, 2017 Bonanni et al, 2014 [57,58] No clinical study after 8 years 7ERT effects in vision [32,33] Case report (Yamanishi R et al, 2019) [59] No clinical study after 5 years (8) ERT effect in autoimmune anemia, thrombocytopenia, or thrombocytopenic purpura [34,35] Case report (Alcántara-Ortigoza et al, 2016) [60] No clinical study after 8 years (9) Botulinum Toxin for the treatment of equinus deformity with an ERT [36] No new citations No clinical study after 8 years (10) ERT effects in involuntary movements (chorea) [37] No new citations No prospective study after 12 years (11) Early ERT effects in bone abnormalities [38] Cohort study (Manara R [39][40][41][42][43][44][45][46][47][48][49]. ** This study analyzed two novelties proposed by previous case reports.…”

“…Novelties proposed in case reports of ERT in MPS-II patients and in clinical studies citing these case reports. References [16][17][18][19][20][23][24][25][26][27][28][29][30][31][32][33][34][35][36] are cited in the supplementary materials.…”

“…Novelties proposed in case reports of ERT in MPS-II patients and in clinical studies citing these case reports. References [ 16 , 17 , 18 , 19 , 20 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , …”