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Hereditary tyrosinaemia type I is an autosomal recessive inborn error of tyrosine catabolism caused by a deficiency of the enzyme fumarylacetoacetase that results in liver failure, hepatocellular carcinoma, renal tubular dysfunction and acute intermittent porphyria. When treated with liver transplantation, tyrosinaemia type I was considered to be cured. Some years after the first liver transplantations in these patients, some reports focused on the renal function after transplantation. These reports showed that urinary succinylacetone excretion remained but that tubular function normalized. In this report we discuss the long-term renal follow-up (mean follow-up time 11 years, range 7-14 years) after liver transplantation in 9 patients with tyrosinaemia type I treated by liver transplantation in our centre. An evaluation was made of renal function and succinylacetone excretion in urine. In all patients we found a persistent excretion of succinylacetone in the urine. With respect to the glomerular function, we can conclude that there is no clear change in GFR. At the same time, tubulopathy persisted in some patients. We consider that excretion of metabolites such as succinylacetone will be an important contributing factor to tubular dysfunction after liver transplantation in patients with tyrosinaemia type I. Therefore, notwithstanding the major effect of liver transplantation on tyrosine metabolism, renal tubular dysfunction remains at risk and needs careful monitoring. Progressive tubular dysfunction can cause glomerular damage. The use of low-dose NTBC might be considered after liver transplantation in case of tubulopathy to prevent progression of tubular and glomerular dysfunction.

Contains fulltext : 89600.pdf (Publisher’s version ) (Closed access) INTRODUCTION: Cystinosis is an autosomal recessive disorder leading to intralysosomal cystine accumulation in various tissues. It causes renal Fanconi syndrome and end stage renal failure around the age of 10 years if not treated with cysteamine. Children with cystinosis seem to have a normal intelligence but frequently show learning difficulties. These problems may be due to specific neurocognitive deficits rather than impaired renal function. Whether cysteamine treatment can improve cognitive functioning of cystinosis patients is thus far unknown. We aim to analyze neurocognitive functioning of school-aged cystinosis patients treated with cysteamine in order to identify specific deficits that can lead to learning difficulties. PATIENTS AND METHODS: Fourteen Dutch and Belgian school-aged cystinosis patients were included. Glomerular filtration rate was estimated using the Schwartz formula. Children were tested for general intelligence, visual-motor integration, inhibition, interference, sustained attention, accuracy, planning, visual memory, processing speed, motor planning, fluency and speed, and behavioural and emotional functioning using standardized methods. RESULTS: Glomerular filtration rate ranged from 22 to 120 ml min(-1) 1.73 m(-2). Median full-scale intelligence was below the average of a normal population (87, range 60-132), with a discrepancy between verbal (median 95, range 60-125) and performance (median 87, range 65-130) intelligence. Over 50% of the patients scored poorly on visual-motor integration, sustained attention, visual memory, planning, or motor speed. The other tested areas showed no differences between patients' and normal values. CONCLUSION: Neurocognitive diagnostics are indicated in cystinosis patients. Early recognition of specific deficits and supervision from special education services might reduce learning difficulties and improve school careers. 01 december 2010