Ocular manifestation of mucopolysaccharidosis I-S (Scheie's syndrome)

Background: Bilateral stromal corneal opacifications are a differential diagnostical challenge to identify associated systemic diseases. Case-report: A 47-year old civil engineer (height 167 cm) with bilateral stromal corneal clouding presented with visual loss for the last 27 years: VA 20/100 OD and 20/50 OS (following penetrating keratoplasty OS). The cornea showed milky-whitish, cloudy, diffuse stromal deposits without a separate lipoid arc. The posterior segment showed tapetoretinal degeneration. Scotopic ERG was decreased. A suspicious stiffness of interphalangeal joints on both hands was observed. There was an aortic and mitral insufficiency grade I. Serum levels of LDL, HDL and triglycerids were normal. The biomicroscopical diagnosis of Scheie's syndrome (mucopolysaccharidosis I-S) was confirmed by a deficiency of alpha-L-iduronidase in leukocytes (0.02 nmol/min/mg protein, normal range: 0.3-1.5). Conclusion: The differential diagnosis of bilateral corneal stromal opacification includes in addition to the mucopolysaccharidoses HDL-deficiency diseases (LCAT deficiency, Tangier disease, Fish eye disease), Schnyder's crystalline stromal dystrophy, cystinosis, gout and mucolipidoses. MPS I-S may easily be detected by alpha-L-iduronidase deficiency in leukocytes and increased mucopolysaccharides in the urine. Furthermore, patients with NIPS I-S need general medical care because of cardiovascular abnormalities, joint stiffness and myopathies.