Effects of early cysteamine therapy on thyroid function and growth in nephropathic cystinosis.
ABSTRACT Primary hypothyroidism is a known complication of nephropathic cystinosis, a lysosomal storage disorder characterized by renal failure as well as deterioration of other organs. The drug cysteamine depletes lysosomes of cystine and helps preserve renal function and enhance growth in cystinosis patients. To determine whether cysteamine also prevents hypothyroidism, we retrospectively divided 101 patients into group A (n = 28; well treated), group B (n = 26; partially treated), and group C (n = 47; poorly treated). Lifetable analysis indicated a significantly higher probability of remaining free of L-T4 replacement in group A vs. group B (P = 0.09) or group C (P = 0.004). Cysteamine therapy also improved mean height z-scores (-2.17 in group A, -3.04 in group B, and -4.07 in group C) and reduced the bone age deficit (i.e. chronological age minus bone age) by 1.5 yr for every 10 yr of previous cysteamine therapy. We conclude that in addition to its other salutary effects, oral cysteamine therapy helps prevent hypothyroidism and enhances growth in patients with nephropathic cystinosis.
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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
Article: Cystinosis: a new perspective[Show abstract] [Hide abstract]
ABSTRACT: Cystinosis is a rare, autosomal recessive inherited lysosomal storage disease. It is the most frequent and potentially treatable cause of the inherited renal Fanconi syndrome. If left untreated, renal function rapidly deteriorates towards end-stage renal disease by the end of the first decade of life. Due to its rarity and non-specific presentation, the entity is often not promptly recognized resulting in delayed diagnosis. Two major milestones in cystinosis management, cystine-depleting therapy with cysteamine and renal allograft transplantation, have had a considerable impact on the natural history and prognosis of cystinosis patients. However, due to its significant side effects and a strict 6-hourly dosing regimen, non-adherence to the immediate release of cysteamine bitartrate formulation (Cystagon®) is a major issue that might affect long-term outcome. Recently, a new twice-daily administered delayed-release enteric-coated formula of cysteamine bitartrate (Procysbi(TM)) has been approved by the European Medical Agency for the treatment of cystinosis, and has been shown to be safe and effective. This delayed-release cysteamine has the potential to improve compliance and hence prognosis, through its better dosing regimen, positive impact on quality of life and possibly less side-effects, and is now tested in an ongoing long-term clinical trial. Longer survival of patients with cystinosis makes transition from pediatric to adult-oriented care another challenge in cystinosis management and requires an extended multidisciplinary approach.01/2015; DOI:10.1179/2295333714Y.0000000113
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ABSTRACT: Cystinosis is caused by mutations in the CTNS gene (17p13.2), which encodes for a lysosomal cystine/proton symporter termed cystinosin. It is the most common cause of inherited renal Fanconi syndrome in young children. Because of its rarity, the diagnosis and specific treatment of cystinosis are frequently delayed, which has a significant impact on the overall prognosis. In this document, we have summarized expert opinions on several aspects of the disease to improve knowledge and provide guidance for diagnosis and treatment.Nephrology Dialysis Transplantation 09/2014; 29(suppl 4):iv87-iv94. DOI:10.1093/ndt/gfu090 · 3.49 Impact Factor