1/12. glomerulonephritis in late-onset cystinosis. Report of two cases and review of the literature.This paper describes the clinical history of two male nontwin siblings with late-onset cystinosis, a variant of cystine storage disease. The diagnosis was established clinically and confirmed by measurement of cystine concentrations in leucocytes and skin-fibroblasts. Both patients presented with an incomplete nephrotic syndrome and renal biopsy showed, in addition to lesions of polykaryocytosis, a picture of focal and segmental glomerular hyalinosis. Renal function was stable in one patient over a follow-up period of two years; the other patient progressed toward terminal renal failure and was successfully transplanted.- - - - - - - - - - ranking = 1keywords = storage disease, storage (Clic here for more details about this article) |
2/12. CTNS mutations in African American patients with cystinosis.cystinosis, an autosomal recessive lysosomal storage disorder, is rarely diagnosed in african americans. The disease results from mutations in the gene CTNS; at least 55 such mutations have been reported. By far the most common is a 57,257-bp deletion of Northern European origin encompassing most of the CTNS gene. We performed mutation analysis on dna from four African American patients with cystinosis. In one individual with classical, nephropathic cystinosis, we identified a new molecular defect, i.e., a homozygous GT-->CC substitution at the 5 position of IVS 5 of CTNS (IVS 5 5 GT-->CC). The out-of-frame splicing of exon 5 creates a null allele consistent with the patient's severe phenotype. Two patients were heterozygous and one homozygous for the common 57-kb deletion allele, reflecting the admixture of African and Northern European gene pools in north america. The two african americans heterozygous for the 57-kb deletion were also hemizygous for a 928G-->A change, associated with ocular or nonnephropathic cystinosis. These two individuals are the only known african americans with ocular cystinosis. We conclude that the diagnosis of cystinosis should be entertained in african americans with symptoms of the disease, and that mutation analysis for the 57-kb deletion should be considered in this group of patients.- - - - - - - - - - ranking = 30.173607343528keywords = lysosomal storage, storage (Clic here for more details about this article) |
3/12. Parenchymal organ cystine depletion with long-term cysteamine therapy.Nephropathic cystinosis is a lysosomal storage disorder characterized by renal failure, multisystem organ damage, and poor growth. Oral cysteamine therapy retards renal deterioration and enhances growth, but parenchymal organ cystine depletion has never been documented. We measured skeletal muscle cystine in 11 cystinosis patients not treated with cysteamine; analysis of their values plus 11 published values showed that muscle cystine increases linearly with age in cystinosis patients (slope, 0.074 nmol half-cystine/mg wet wt/year). In contrast, 15 patients treated for 4 to 11 years with oral cysteamine had a relatively constant muscle cystine content (slope, 0.004 nmol half-cystine/mg wet wt/year). The treated patients' mean muscle cystine, 0.091 /- 0.064 (SD) nmol half-cystine/mg wet wt, was significantly less (P < 0.001) than that for the 11 youngest untreated patients, 0.754 /- 0.534 nmol half-cystine/mg wet wt. On postmortem examination, a 9-year-old cystinosis patient treated for 8 years with oral cysteamine had liver, kidney, pancreas, lung, and spleen cystine values 5 to 90 times lower than those of an untreated age-matched control. We conclude that long-term oral cysteamine therapy routinely depletes cystinotic skeletal muscle of cystine; cysteamine is the treatment of choice for the prevention of both renal and nonrenal complications of cystinosis.- - - - - - - - - - ranking = 30.173607343528keywords = lysosomal storage, storage (Clic here for more details about this article) |
4/12. Swallowing dysfunction in 101 patients with nephropathic cystinosis: benefit of long-term cysteamine therapy.Nephropathic cystinosis is a rare, autosomal recessive lysosomal storage disorder caused by mutations in the CTNS gene that codes for a cystine transporter in the lysosomal membrane. Affected patients store 50-100 times the normal amounts of cystine in their cells, and suffer renal tubular and glomerular disease, growth retardation, photophobia, and other systemic complications, including a myopathy and swallowing dysfunction. Using videofluoroscopy and ultrasound examinations, we assessed the swallowing function of 101 patients with nephropathic cystinosis on their most recent admission to the National Institutes of health Clinical Center between 1987 and 2004. These patients ranged in age from 6 to 45 years; more than half had significant complaints of swallowing difficulty. On examination of barium swallow, the oral, pharyngeal, and esophageal phases of swallowing were abnormal in 24%, 51%, and 73% of patients, respectively. The frequency of dysfunction increased with age for each phase of swallowing. Both the Swallowing Severity Score (a measure of dysfunction on barium swallow) and the Oral Muscle Composite Score (a reflection of vocal strength, oral-facial movement, and tongue and lip function) increased (that is, worsened) with the number of years that a patient was not receiving treatment with cysteamine, the cystine-depleting agent of choice in cystinosis. The severity scores decreased with the number of years on cysteamine therapy. The Swallowing Severity Score varied directly with the severity of muscle disease, but was not correlated with the presence or absence of the 57-kb CTNS deletion that commonly occurs in nephropathic cystinosis patients. We conclude that swallowing dysfunction in cystinosis presents a risk of fatal aspiration, correlates with the presence of muscle atrophy, and, based on cross-sectional data, increases in frequency with age and number of years without cysteamine treatment. cystine-depleting therapy with cysteamine should be considered the treatment of choice for both pre- and posttransplant cystinosis patients.- - - - - - - - - - ranking = 30.173607343528keywords = lysosomal storage, storage (Clic here for more details about this article) |
5/12. cystinosis as a cause of noncirrhotic portal hypertension.cystinosis is a rare autosomal recessive storage disorder, characterized by the abnormal accumulation of cystine in cellular lysosomes. This accumulation, which can occur in any organ system, leads to crystallization of trapped cystine and ultimately cellular death. Hepatic manifestations of cystinosis although rare, have been described in the literature. However, to our knowledge, only one other case of non-cirrhotic portal hypertension secondary to cystine accumulation in kupffer cells has been reported. In this case and ours, portal hypertension was found in the absence of bridging fibrosis. Furthermore, in our case, for the majority of the patient's course, hepatic synthetic function remained normal. cysteamine is therapeutic in this disorder, and can lead to significant removal of cystine, and thus to reversibility of disease, however, it requires high doses and must be taken regularly. Porto-systemic shunting in combination with aggressive medical therapy could potentially benefit patients who develop non-cirrhotic portal hypertension in this clinical setting.- - - - - - - - - - ranking = 0.35417648397673keywords = storage (Clic here for more details about this article) |
6/12. central nervous system involvement in nephropathic cystinosis.Nephropathic cystinosis, an autosomal recessive lysosomal storage disorder due to impaired cystine transport, causes damage to multiple organs that results in end-stage renal disease, hypothyroidism, and retinopathy, usually in childhood. dialysis and renal transplantation now frequently enable patients with cystinosis to live into adulthood. Examinations at autopsy of a 28-year-old man who died of complications of this disease showed deposits of cystine crystals in multiple organs. There was severe cerebral involvement with multifocal cystic necrosis, dystrophic calcification, spongy change, and vacuolization that had produced profound neurologic deficits. Electron microscopy of the brain documented cytoplasmic deposition of cystine crystals in membrane bound vacuoles within the cytoplasm of pericytes and within parenchymal cells of the white matter. While affected patients who have received renal transplants may no longer die from renal failure, serious, potentially life-threatening, neurologic complications of this disorder may supervene.- - - - - - - - - - ranking = 30.173607343528keywords = lysosomal storage, storage (Clic here for more details about this article) |
7/12. The value of conjunctival biopsy in childhood cystinosis.cystinosis is frequently presented with cystine storage in the cornea and conjunctiva, and the diagnosis can be established by slit-lamp examination. It can also be confirmed by electron microscopy of a conjunctival biopsy. The present paper reports on a 16-month-old boy with Fanconi's syndrome, in whom the slit-lamp examination did not show crystal deposits of cystine in the conjunctiva. The ultrastructural study of the conjunctival biopsy demonstrated polygonal crystals within double membrane-limited organelles located in fibroblasts. Similar crystals were subsequently found in a kidney biopsy. We therefore think that conjunctival biopsy is a valuable diagnostic tool prior to performing renal biopsy, even in cases with negative findings by ophthalmologic examination.- - - - - - - - - - ranking = 0.35417648397673keywords = storage (Clic here for more details about this article) |
8/12. Biochemical phenotyping of a single sibship with both cystinosis and fabry disease.Two lysosomal storage diseases, cystinosis and fabry disease, were diagnosed clinically in different members of a single sibship. The possibility that the affected sister and brother might have related disorders with disparate manifestations was pursued. The four principal family members were tested for heterozygote status with respect to serum and leukocyte alpha-galactosidase A activity, urinary trihexosylceramide excretion, and the capacity to engage in cystine counter-transport across leukocyte lysosome membranes. Results were consistent with classical autosomal recessive inheritance in the case of cystinosis and X-linked inheritance for fabry disease, confirming that this family represents an example of two rare disorders occurring in the same sibship.- - - - - - - - - - ranking = 87.117972746064keywords = lysosomal storage disease, lysosomal storage, storage disease, storage (Clic here for more details about this article) |
9/12. Nephropathic cystinosis with central nervous system involvement.Nephropathic cystinosis is associated with end-stage renal failure, retinal damage, and hypothyroidism. patients may now survive past the first decade of life with the use of dialysis and renal transplantation. Examination of a 24-year-old woman with this disorder revealed ovarian failure, mildly abnormal results on a glucose tolerance test, intermittent confusion, short-term memory loss, and cerebral atrophy on computerized axial tomography. autopsy examination at age 25 years revealed cystine storage in multiple tissues including the atrophic ovaries, pancreatic islet cells, the aorta, and the brain. Dysfunction of multiple organ systems may develop in patients with cystinosis who survive into adulthood. This emphasizes the need for a systemic therapy for cystinosis.- - - - - - - - - - ranking = 0.35417648397673keywords = storage (Clic here for more details about this article) |
10/12. Lysosomal cystine transport in cystinosis variants and their parents.Children with nephropathic cystinosis store 50 to 100 times normal amounts of free cystine in many cells and display negligible lysosomal cystine transport in their leucocytes and cultured fibroblasts. A patient with intermediate (adolescent) cystinosis exhibited a similar deficiency of egress out of fibroblast lysosome-rich granular fractions. Another individual with benign (adult) cystinosis accumulated only 2.85 nmol 1/2 cystine/mg leucocyte protein, or 20-50% of the amount stored in nephropathic cystinosis leucocytes. His leucocyte granular fractions also displayed substantial residual cystine-carrying capacity, as determined by measurement of lysosomal cystine counter-transport. We conclude that the variant forms of cystinosis represent a continuum of lysosomal cystine storage, with the varied clinical presentation depending on the amount of residual cystine-carrying capacity, genetic predispositions, and differential tissue susceptibilities.- - - - - - - - - - ranking = 0.35417648397673keywords = storage (Clic here for more details about this article) |
| | Next -> |