Fibroblast growth factor 23 and calcium-phosphate metabolism in relation to cardiovascular risk factors in patients with type 1 diabetes.

BACKGROUND: Cardiovascular disease (CVD) is the major cause of mortality in type 1 diabetes (T1D). The objective of this study is to evaluate fibroblast growth factor 23 (FGF23) and calcium-phosphate metabolism in relation to cardiovascular risk factors in adults with and without T1D. METHODS: A case-control study was conducted using data from patients with T1D and age- and sex matched controls without T1D from the Lifelines Cohort Study. RESULTS: We included 302 adults in the T1D group and 302 adults in the control group. Median age was 42 years. Median glycosylated hemoglobin (HbA1c) in the T1D group was 7.8%. FGF23 of all patients with T1D was not significantly different from controls. Females with T1D had significantly higher FGF23 than males with T1D (83.3 vs 69.3 U/mL, p = 0.002), this was not observed in controls. Serum phosphate, calcium, and alkaline phosphatase were higher and parathyroid hormone was lower in patients with T1D, compared to controls (all p < .001), all within normal range. In the T1D group, FGF23 was positively correlated with serum phosphate (p < .001), alkaline phosphatase (p = .01), and calcium (p = .030), these correlations were not observed in controls. Median FGF23 was significantly higher in current smokers than in nonsmokers with T1D (84.9 vs 73.5 U/mL, p < .05). CONCLUSIONS: Serum calcium, phosphate, and alkaline phosphatase were higher in patients with T1D than in controls and were positively correlated to FGF23 in patients with T1D. Current smokers with T1D had higher FGF23 than nonsmokers with T1D. These findings may contribute to the increased risk of CVD in patients with T1D.

OHVIRA syndrome: Early recognition prevents genitourinary complications.

Introduction: The obstructed hemivagina and ipsilateral renal anomaly (OHVIRA) syndrome is characterized by the triad uterus didelphys, obstructed hemivagina, and ipsilateral renal dysplasia. To make a radiological diagnosis, knowledge of this syndrome is of paramount importance. Early recognition may prevent complications such as unnecessary surgical procedures, endometriosis, and infections, which could adversely affect fertility. Case report: A 1-day-old female newborn in whom a right-sided cystic kidney abnormality was seen on antenatal ultrasound was admitted with anuria and intralabial mass. Besides the multicystic dysplastic right kidney, ultrasound revealed a uterus didelphys with right-sided uterus dysplasia, an obstructed right hemivagina, and an ectopic ureteric insertion. The diagnosis of obstructed hemivagina and ipsilateral renal anomaly syndrome with hydrocolpos was made and the hymen was incised. Later, ultrasound helped in diagnosing a pyelonephritis in the afunctional right kidney that was not draining into the bladder (hence no culture could be obtained), requiring intravenous antibiotics and a nephrectomy. Discussion: Obstructed hemivagina and ipsilateral renal anomaly syndrome is an anomaly of the Müllerian and Wolffian ducts of unknown cause. Patients typically present after menarche with (progressive) abdominal pain, dysmenorrhea, or urogenital malformations. In contrast, prepubertal patients can present with urinary incontinence or an (external) vaginal mass. The diagnosis is confirmed by an ultrasound or magnetic resonance imaging. Follow-up includes repeated ultrasounds and monitoring of kidney function. Treatment consists of drainage of the hydrocolpos/hematocolpos; in some cases, further surgery is indicated. Conclusion: Consider obstructed hemivagina and ipsilateral renal anomaly syndrome in girls with genitourinary abnormalities: early recognition prevents complications later in life.

Outcome of infantile nephropathic cystinosis depends on early intervention, not genotype: A multicenter sibling cohort study.

Infantile nephropathic cystinosis (INC) is an inheritable lysosomal storage disorder characterized by lysosomal cystine accumulation, progressive kidney disease, and multiple extrarenal complications (ERCs). Cysteamine postpones the onset of end-stage kidney disease (ESKD) and reduces the incidence of ERCs; however, cysteamine is generally initiated upon establishment of the renal Fanconi syndrome (FS) and partial loss of kidney function, whereas data on long-term effects of cysteamine administered from neonatal age are lacking. An international multicenter retrospective cohort study of siblings with INC was set up to investigate the outcome in relation to age at initiation of cysteamine versus CTNS genotype, with attention to patients treated with cysteamine from neonatal age. None of the siblings treated from neonatal age (n = 9; age 10 ± 6 years) had reached ESKD, while 22% of their index counterparts (n = 9; age 14 ± 5 years) had commenced renal replacement therapy. Siblings treated with cysteamine from the onset of symptoms at a younger age compared with their index counterparts, reached ESKD at a significant older age (13 ± 3 vs. 10 ± 3 years, p = 0.002). In contrast, no significant difference in ERCs was observed between sibling and index patients, independently from the age at initiation of cysteamine. The CTNS genotype had no impact on the overall outcome in this cohort. In INC, presymptomatic treatment with cysteamine results in a better renal outcome in comparison to treatment initiated from the onset of symptoms. This justifies including cystinosis into newborn screening programs. SYNOPSIS: In infantile nephropathic cystinosis, presymptomatic treatment with cysteamine improves the renal outcome which justifies the inclusion of cystinosis into newborn screening programs.

Fertility in Cystinosis.

Cystinosis is a rare inheritable lysosomal storage disorder characterized by cystine accumulation throughout the body, chronic kidney disease necessitating renal replacement therapy mostly during adolescence, and multiple extra-renal complications. The majority of male cystinosis patients are infertile due to azoospermia, in contrast to female patients who are fertile. Over recent decades, the fertility status of male patients has evolved from a primary hypogonadism in the era before the systematic treatment with cysteamine to azoospermia in the majority of cysteamine-treated infantile cystinosis patients. In this review, we provide a state-of-the-art overview on the available clinical, histopathological, animal, and in vitro data. We summarize current insights on both cystinosis males and females, and their clinical implications including the potential effect of cysteamine on fertility. In addition, we identify the remaining challenges and areas for future research.

Human and animal fertility studies in cystinosis reveal signs of obstructive azoospermia, an altered blood-testis barrier and a subtherapeutic effect of cysteamine in testis.

Cystinosis is an inherited metabolic disorder caused by autosomal recessive mutations in the CTNS gene leading to lysosomal cystine accumulation. The disease primarily affects the kidneys followed by extra-renal organ involvement later in life. Azoospermia is one of the unclarified complications which are not improved by cysteamine, which is the only available disease-modifying treatment. We aimed at unraveling the origin of azoospermia in cysteamine-treated cystinosis by confirming or excluding an obstructive factor, and investigating the effect of cysteamine on fertility in the Ctns-/- mouse model compared with wild type. Azoospermia was present in the vast majority of infantile type cystinosis patients. While spermatogenesis was intact, an enlarged caput epididymis and reduced levels of seminal markers for obstruction neutral α-glucosidase (NAG) and extracellular matrix protein 1 (ECM1) pointed towards an epididymal obstruction. Histopathological examination in human and mouse testis revealed a disturbed blood-testis barrier characterized by an altered zonula occludens-1 (ZO-1) protein expression. Animal studies ruled out a negative effect of cysteamine on fertility, but showed that cystine accumulation in the testis is irresponsive to regular cysteamine treatment. We conclude that the azoospermia in infantile cystinosis is due to an obstruction related to epididymal dysfunction, irrespective of the severity of an evolving primary hypogonadism. Regular cysteamine treatment does not affect fertility but has subtherapeutic effects on cystine accumulation in testis.

First Successful Conception Induced by a Male Cystinosis Patient.

Cystinosis is a rare autosomal recessive lysosomal storage disease characterized by multi-organ cystine accumulation, leading to renal failure and extra-renal organ dysfunction. Azoospermia of unknown origin is the main cause of infertility in all male cystinosis patients. Although spermatogenesis has shown to be intact at the testicular level in some patients, no male cystinosis patient has been reported yet to have successfully induced conception.We present the first successful conception ever reported, induced by a 27-year-old male renal transplant infantile nephropathic cystinosis patient through percutaneous epididymal sperm aspiration (PESA) followed by intracytoplasmatic sperm injection (ICSI). After 36 weeks and 6 days of an uncomplicated pregnancy, a dichorial diamniotic (DCDA) twin was born with an appropriate weight for gestational age and in an apparently healthy status. Moreover, we demonstrate that the sperm of epididymal origin in selected male cystinosis patients can be viable for inducing successful conception.Our observation opens a new perspective in life for many male cystinosis patients whom nowadays have become adults, by showing that despite azoospermia fathering a child can be realized. In addition, our findings raise questions about the possibility of sperm cryopreservation at a young age in these patients.

Clinical and molecular aspects of distal renal tubular acidosis in children.

BACKGROUND: Distal renal tubular acidosis (dRTA) is characterized by hyperchloraemic metabolic acidosis, hypokalaemia, hypercalciuria and nephrocalcinosis. It is due to reduced urinary acidification by the α-intercalated cells in the collecting duct and can be caused by mutations in genes that encode subunits of the vacuolar H+-ATPase (ATP6V1B1, ATP6V0A4) or the anion exchanger 1 (SLC4A1). Treatment with alkali is the mainstay of therapy. METHODS: This study is an analysis of clinical data from a long-term follow-up of 24 children with dRTA in a single centre, including a genetic analysis. RESULTS: Of the 24 children included in the study, genetic diagnosis was confirmed in 19 patients, with six children having mutations in ATP6V1B1, ten in ATP6V0A4 and three in SLC4A1; molecular diagnosis was not available for five children. Five novel mutations were detected (2 in ATP6V1B1 and 3 in ATP6V0A4). Two-thirds of patients presented with features of proximal tubular dysfunction leading to an erroneous diagnosis of renal Fanconi syndrome. The proximal tubulopathy disappeared after resolution of acidosis, indicating the importance of following proximal tubular function to establish the correct diagnosis. Growth retardation with a height below -2 standard deviation score was found in ten patients at presentation, but persisted in only three of these children once established on alkali treatment. Sensorineural hearing loss was found in five of the six patients with an ATP6V1B1 mutation. Only one patient with an ATP6V0A4 mutation had sensorineural hearing loss during childhood. Nine children developed medullary cysts, but without apparent clinical consequences. Cyst development in this cohort was not correlated with age at therapy onset, molecular diagnosis, growth parameters or renal function. CONCLUSION: In general, the prognosis of dRTA is good in children treated with alkali.

Pediatric lupus nephritis presenting with terminal renal failure.

A 12-year-old Congolese girl presented with acute renal failure, edema, hypertension, hemoptysis, hematuria, and proteinuria after a history of throat infection. Renal ultrasound showed kidneys of normal size, with increased echogenicity of the cortical parenchyma and decreased corticomedullary differentiation. Other additional investigations showed pancytopenia with decreased complement (low C3 and C4). Antinuclear antibodies were strongly positive, including anti-double stranded DNA. Renal biopsy confirmed severe grade IV lupus nephritis. She was treated with high-dose steroids, mycophenolate mofetil and hydroxychloroquine, in addition to hemodialysis. After one week of intensive treatment, diuresis recovered and dialysis could be stopped after six sessions. We describe an uncommon case of severe lupus nephritis, presenting with terminal renal failure. Since the rarity of this disease presentation, other more common diagnoses have to be considered. Once the diagnosis of lupus nephritis is established, a choice has to be made between the different induction treatment protocols. The patient's ethnic background and other supportive therapies, such as the need for dialysis, can help to make this choice.

Cystinosis: a new perspective.

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.

Management dilemmas in pediatric nephrology: Cystinosis.

BACKGROUND: Cystinosis is a rare, inherited autosomal recessive disease caused by the accumulation of free cystine in lysosomes. It is treated by the administration of cysteamine, which should be monitored by trough white blood cell (WBC) cystine measurements to ensure effective treatment. CASE-DIAGNOSIS/TREATMENT: The index case had an older brother who had previously been diagnosed with cystinosis, allowing early diagnosis of the index case at the age of 5 months. Cysteamine therapy was started at the age of 3 years; however, monitoring of WBC cystine levels did not occur on a regular basis during most of his life. Growth retardation improved after correction of electrolyte disturbances, the initiation of cysteamine therapy and treatment with recombinant human growth hormone. Renal replacement therapy was started at the age of 11 years, and renal transplantation was performed at the age of 12 years. Extra-renal cystine accumulation caused multiple endocrinopathies (including adrenal insufficiency, hypothyroidism and primary hypogonadism), neurological symptoms, pancytopenia owing to splenomegaly and portal hypertension due to nodular regenerative hyperplasia, aggravated by splenic vein thrombosis and partial portal vein thrombosis. The patient died of diffuse intra-abdominal bleeding caused by severe portal hypertension. CONCLUSION: Cysteamine treatment should be started as early as possible, and dosage should be monitored and adapted based on trough WBC cystine levels. RELEVANT INTERNATIONAL GUIDELINE: Emma F et al. (2014) Nephropathic cystinosis: an international consensus document. Nephrol Dial Transplant 29:iv87-iv94.

Improving the prognosis of nephropathic cystinosis.

Cystinosis is an autosomal recessive inherited lysosomal storage disease. It is characterized by generalized proximal tubular dysfunction known as renal Fanconi syndrome and causes end-stage renal disease by the age of about 10 years if left untreated. Extrarenal organs are also affected, including the thyroid gland, gonads, pancreas, liver, muscle, and brain. Treatment consists of administration of cysteamine, resulting in depletion of cystine that is trapped inside the lysosomes. Since cysteamine has a short half-life, it should be administered every 6 hours. Recently, a new delayed-release formulation was marketed, that should be administered every 12 hours. The first studies comparing both cysteamine formulations show comparable results regarding white blood cell cystine depletion (which serves as a measure for cystine accumulation in the body), while a slightly lower daily dose of cysteamine can be used.

Copper deficiency in patients with cystinosis with cysteamine toxicity.

OBJECTIVES: To assess whether copper deficiency plays a role in the recently described cysteamine toxicity in patients with cystinosis, and to examine whether polymorphisms in copper transporters, lysyl oxidase, and/or type I procollagen genes could be responsible for the occurrence of cysteamine toxicity in a small subset of patients with cystinosis. STUDY DESIGN: Thirty-six patients with cystinosis were included: 22 with Fanconi syndrome (including 7 with cysteamine toxicity), 12 after renal transplantation, 1 receiving hemodialysis, and 1 with ocular cystinosis. Serum copper and ceruloplasmin levels and urinary copper/creatinine ratio were measured. Genes ATP7A and CTR1 (encoding copper transporters), LOX (encoding lysyl oxidase), and COL1A1 and COL1A2 (encoding type I procollagen) were analyzed in patients with (n = 6) and without (n = 5) toxicity. Fibroblast (pro)collagen synthesis was compared in patients with (n = 3) and those without (n = 2) cysteamine toxicity. RESULTS: All 22 patients with Fanconi syndrome had increased urinary copper excretion. Serum copper and ceruloplasmin levels were decreased in 9 patients, including all 7 patients with cysteamine toxicity. No specific sequence variations were associated with toxicity. All fibroblasts exhibited normal (pro)collagen synthesis. CONCLUSION: Patients with cystinosis with cysteamine toxicity demonstrate copper deficiency. This can cause decreased activity of lysyl oxidase, the enzyme that generates the aldehydes required for collagen cross-linking. Thus, copper supplementation might prevent cysteamine toxicity.

Cysteamine: an old drug with new potential.

Cysteamine is an amino thiol with the chemical formula HSCH2CH2NH2. Endogenously, cysteamine is derived from coenzyme A degradation, although its plasma concentrations are low. Most experience with cysteamine as a drug originates from the field of the orphan disease cystinosis, in which cysteamine is prescribed to decrease intralysosomal cystine accumulation. However, over the years, the drug has been used for several other applications both in vitro and in vivo. In this article, we review the different applications of cysteamine, ending with an overview of ongoing clinical trials for new indications, such as neurodegenerative disorders and nonalcoholic fatty liver disease (NAFLD). The recent development of an enteric-coated cysteamine formulation makes cysteamine more patient friendly and will extend its applicability for both old and new indications.

Stem cell microvesicles transfer cystinosin to human cystinotic cells and reduce cystine accumulation in vitro.

Cystinosis is a rare disease caused by homozygous mutations of the CTNS gene, encoding a cystine efflux channel in the lysosomal membrane. In Ctns knockout mice, the pathologic intralysosomal accumulation of cystine that drives progressive organ damage can be reversed by infusion of wildtype bone marrow-derived stem cells, but the mechanism involved is unclear since the exogeneous stem cells are rarely integrated into renal tubules. Here we show that human mesenchymal stem cells, from amniotic fluid or bone marrow, reduce pathologic cystine accumulation in co-cultured CTNS mutant fibroblasts or proximal tubular cells from cystinosis patients. This paracrine effect is associated with release into the culture medium of stem cell microvesicles (100-400 nm diameter) containing wildtype cystinosin protein and CTNS mRNA. Isolated stem cell microvesicles reduce target cell cystine accumulation in a dose-dependent, Annexin V-sensitive manner. Microvesicles from stem cells expressing CTNS(Red) transfer tagged CTNS protein to the lysosome/endosome compartment of cystinotic fibroblasts. Our observations suggest that exogenous stem cells may reprogram the biology of mutant tissues by direct microvesicle transfer of membrane-associated wildtype molecules.

Halitosis in cystinosis patients after administration of immediate-release cysteamine bitartrate compared to delayed-release cysteamine bitartrate.

Halitosis due to dimethylsulfide (DMS) generation is a major side effect of cysteamine in the treatment of cystinosis. Recently, an enteric coated formulation of cysteamine bitartrate (RP103) administered twice daily was demonstrated to be non-inferior for lowering WBC cystine levels compared to the non-enteric coated formulation (Cystagon®), administered 4 times per day. Since both formulations had different pharmacokinetic profiles, we compared DMS breath levels after administration of either RP103 or Cystagon® in four cystinosis patients. Although cysteamine areas under the curve (AUCs) were comparable, AUC of DMS was lower after the administration of RP103 compared to Cystagon®. This observation is of importance in cystinosis patients, since halitosis hampers compliance with cysteamine therapy.

Detailed studies of growth hormone secretion in cystinosis patients.

BACKGROUND: Cystinosis is an autosomal recessive disorder characterized by intralysosomal cystine accumulation. Growth retardation is more pronounced in cystinosis than in other chronic kidney diseases and is mostly not corrected by cysteamine. METHODS: Growth was evaluated in nine cystinosis patients, all treated with cysteamine, both after cysteamine and recombinant human growth hormone (rhGH) therapy initiation. Growth hormone (GH) secretion was studied by nocturnal GH measurements in four of nine patients and by glucagon test in four of nine patients. RESULTS: RhGH was administered to seven of nine patients. At rhGH initiation, height was below -2 SDS in five of seven patients, final height was above -2 SDS in six of seven. In two patients not treated with rhGH, final height remained below -4 SDS despite cysteamine treatment being started at the age of 6.1 and 8.1 years, respectively. Nocturnal GH secretion was normal in all patients. Glucagon tests revealed GH deficiency in one patient; two of four patients had abnormal GH peak timing. CONCLUSIONS: We present the first reported case of GH deficiency in cystinosis. Although no overt GH deficiency was detected in other patients, abnormal GH peak timing can indicate a subclinical GH secretion problem. RhGH significantly improved growth in cystinosis patients and should be initiated early in life.

Studying nonobstructive azoospermia in cystinosis: histologic examination of testes and epididymis and sperm analysis in a Ctns⁻/⁻ mouse model.

OBJECTIVE: To study the pathogenesis of male infertility in cystinosis due to nonobstructive azoospermia, using a Ctns(-/-) mouse model. DESIGN: Observational case-control study. SETTING: Academic research laboratory. ANIMAL(S): Male C57BL/6 Ctns(-/-) mice were compared with C57BL/6 wild-type (wt) mice. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Fertility was studied using litter size (n = 3 vs. n = 2). After animals were sacrificed, testes, epididymis, and vas deferens were removed for testicular cystine measurements (n = 5 vs. n = 6), histologic studies (n = 3 vs. n = 3), and sperm analysis (n = 3 vs. n = 3). RESULT(S): Mean testicular cystine content was significantly higher in Ctns(-/-) mice compared with wt mice (26.6 ± 1.22 vs. 0.1 ± 0.01 nmol cystine/mg protein). Testes of Ctns(-/-) mice had lower weight compared with wt mice (0.096 ± 0.009 g vs. 0.112 ± 0.004 g), but mice fertility was similar (litter size 6.6 ± 1.4 vs. 6.3 ± 2.6 pups). Neither histologic nor sperm abnormalities were found. CONCLUSION(S): The Ctns(-/-) mouse model generated on C57BL/6 background is not suitable for clarifying the pathogenesis of male infertility in cystinosis. The etiology of nonobstructive azoospermia in these patients remains unclear.

[Lipoblastoma and lipoblastomatosis: especially in children]. / Lipoblastoom en lipoblastomatose: vooral bij kinderen.

Lipoblastoma and lipoblastomatosis are rare benign fatty tumours that mainly occur in children under the age of 3 years. Several body sites can be affected. The term 'lipoblastoma' is reserved for an encapsulated neoplasm; 'lipoblastomatosis' for tumours demonstrating infiltrative growth. Most of the clinical symptoms arise from a mass effect of the tumour on surrounding tissues. The tumours should be differentiated from lipoma, myxoid liposarcoma and hibernoma. A clear distinction can be made by cytogenetic analysis, since each of these tumours is known for its own typical genetic abnormalities. In lipoblastoma and lipoblastomatosis, these include a breakpoint in the 8q11-13 region or polysomy of chromosome 8, both leading to the activation of the oncogenic pleomorphic adenoma gene 1 (PLAG1) on 8q12. Treatment consists of surgical resection; there is no need for radiotherapy or chemotherapy. Clinical outcome depends on the completeness of the resection and damage that is done to the surrounding tissues during surgery.

Cysteamine toxicity in patients with cystinosis.

OBJECTIVE: To report new adverse effects of cysteamine. STUDY DESIGN: Detailed clinical information was obtained from the patients' physicians. RESULTS: New adverse events were reported in 8 of 550 patients with cystinosis treated with cysteamine in Europe during the last 5 years. Detailed clinical information was not available for 2 of these patients, 1 of whom died from cerebral ischemia. The 6 evaluable patients developed vascular elbow lesions (6/6), neurologic symptoms (1/6), bone and muscle pain (2/6), and/or skin striae (2/6). Analysis of biopsy specimens from the elbow lesions demonstrated angioendotheliomatosis with irregular collagen fibers. In 3 of the 6 patients, the daily cysteamine dose exceeded the recommended maximum of 1.95 g/m(2)/day. Dose reduction led to improvement of signs and symptoms in all 6 patients, suggesting a causal relationship with cysteamine administration. CONCLUSION: Cysteamine administration can be complicated by the development of skin, vascular, neurologic, muscular, and bone lesions. These lesions improve after cysteamine dose reduction. Doses >1.95 g/m(2)/day should be prescribed with great caution, but underdosing is not advocated.

Non-invasive measurements of atherosclerosis in adult cystinosis patients.

BACKGROUND: Cystinosis is characterized by intralysosomal cystine accumulation, causing end stage renal disease around 10 years of age if not treated with cysteamine. Cystine accumulation in blood vessels might increase atheroma formation or arterial stiffness and therefore increase the risk for cardiovascular disease (CVD). This study aimed to investigate the risk for CVD by non-invasive measures of atherosclerosis (NIMA) and to evaluate the effect of cysteamine treatment. PATIENTS AND METHODS: Thirteen Dutch adult cystinosis patients were included. White blood cell (WBC) cystine levels, glomerular filtration rate (GFR) and concommitant medications were obtained from medical records. NIMA included carotid intima-media thickness (cIMT, n = 13), pulse wave velocity (PWV, n = 8) and pulse wave analysis (PWA, n = 6). RESULTS: GFR ranged between 4-95 mL/min/1.73 m². All but one patient were treated with cysteamine, mean WBC cystine values ranged between 0.34-1.64 nmol cystine/mg protein, 8 patients had mean WBC cystine levels <1 nmol cystine/mg protein. When compared to healthy subjects, cIMT and PWV levels were above normal values in 1 patient for each measure. PWA measurements showed high augmentation index in three patients who did not receive lipid-lowering medication. When corrected for renal function, cIMT and PWV levels were within the normal range. CONCLUSION: Young adult cystinosis patients treated with cysteamine have no additional risk for CVD when compared to patients with chronic kidney disease of other causes.