Nephropathic cystinosis: posterior segment manifestations and effects of cysteamine therapy.

Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892 , USA.
Ophthalmology (Impact Factor: 6.17). 07/2006; 113(6):1002-9.
Source: PubMed

ABSTRACT Cystinosis is a rare autosomal recessive lysosomal storage disorder characterized by the intracellular accumulation of cystine. Treatment involves intracellular cystine depletion with oral cysteamine. A wide spectrum of ocular pathologic features has been associated with nephropathic cystinosis. We used the largest documented cohort of patients in the world to study the posterior segment manifestations associated with infantile nephropathic cystinosis and to determine retrospectively the effect of chronic oral cysteamine therapy on the frequency of these abnormalities.
Cross-sectional study of a series of patients.
Two hundred eight patients with infantile nephropathic cystinosis were studied at the National Institutes of Health between 1976 and 2004.
All patients underwent an ophthalmic evaluation. Patients older than 11 years also underwent Humphrey static perimetry, and electrophysiological testing was performed when possible.
Visual acuity, retina findings, visual fields, and electroretinographic (ERG) findings.
Pigmentary changes with retinal pigment epithelial mottling, seen as early as infancy, were the most common posterior segment manifestations. Moderate to severe constriction of the visual fields, as well as moderate to severe reduction of rod- and cone-mediated ERG responses, was seen in older patients. The frequency of retinopathy correlated directly with time not receiving oral cysteamine therapy and inversely with time receiving oral cysteamine therapy.
Infantile nephropathic cystinosis has posterior segment complications that can contribute to significant visual handicap. Early initiation of oral cysteamine therapy can reduce the frequency of posterior segment complications in cystinosis patients.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Cystinosis is a rare autosomal recessive disorder characterized by the accumulation of cystine within the cells of different organs. Infantile nephropathic cystinosis is the most common and severe phenotype. With the success of renal transplantation, these patients are now living longer and thus more long-term complications within different organs are becoming apparent. Ophthalmic manifestations range from corneal deposits of cystine crystals to pigmentary retinopathy. With increasing age, more severe ocular complications have been reported. Photophobia is a prominent symptom for patients. With prolonged survival and increasing age, this symptom, along with corneal erosions and blepharospasm, can become debilitating. This review revisits the basic pathogenesis of cystinosis, the ocular manifestations of the disease, and the treatment of corneal crystals.
    Clinical ophthalmology (Auckland, N.Z.) 10/2014; 8:2077-84. DOI:10.2147/OPTH.S36626
  • [Show abstract] [Hide abstract]
    ABSTRACT: There are many disorders that can affect both the kidneys and the eyes. Awareness of the ocular manifestations of kidney disorders is important as it can guide the diagnosis and facilitate the choice of a specific treatment. Conversely, ophthalmologists need to be aware of potential renal manifestations in disorders presenting initially with visual failure. We review disorders affecting both of these organ systems, based upon cases from our clinical practice to highlight the importance of interdisciplinary collaboration.
    Pediatric Nephrology 01/2013; 28(12). DOI:10.1007/s00467-012-2404-5 · 2.88 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Cystinosis is a rare autosomal recessive disorder involving lysosomal storage of the amino acid cystine due to a defect in the membrane transport protein, cystinosin. Since the introduction of kidney transplants and the availability of cystine-depleting medical therapy, this previously fatal disease was transformed into a treatable disorder. Renal allografts and medical therapy targeting the basic metabolic defect have altered the natural hisotry of cystinosis so drastically that patients have a life expectancy extending past 50 years. Consequently, early diagnosis and appropriate therapy are critically important. In this article, we offer a review of the manifestations of cystinosis, including the proximal tubular dysfunction of renal Fanconi syndrome, and discuss the prevention and treatment of the disorder's systemic complications. We focus on the nephropathic forms of cystinosis, aiming to assist nephrologists and other physicians to develop early recognition and appropriate management of cystinosis patients.
    Pediatric Nephrology 08/2012; 28(1). DOI:10.1007/s00467-012-2242-5 · 2.88 Impact Factor