Nephrological abnormalities in patients with transaldolase deficiency

Background. Transaldolase deficiency (OMIM 606003) is a multisystem disorder first described in 2001. Transaldolase is an enzyme of the reversible part of the pentose phosphate pathway. Affected patients have abnormal polyol concentrations in body fluids, mostly in urine. The clinical presentation is variable. The leading symptoms are coagulopathy, thrombocytopenia, hepatosplenomegaly, hepatic fibrosis and dysmorphic features. The objective of our study was to attempt to characterize the renal phenotype of patients with transaldolase deficiency. Methods. Clinical and laboratory data of all nine patients with transaldolase deficiency presently known were gathered by retrospective chart analysis. Results. Nephrological abnormalities were present in seven of the nine patients. The most common findings were low molecular weight (LMW) proteinuria and hypercalciuria. The two oldest patients had moderate chronic kidney failure. In two patients, generalized aminoaciduria was found, two patients had renal phosphate wasting and three patients had hyperchloremic metabolic acidosis. Three patients had anatomical abnormalities. Conclusions. Renal tubular dysfunction is present in the majority of patients with transaldolase deficiency and may lead to chronic renal failure. The combination of unexplained liver dysfunction with LMW proteinuria should prompt metabolic screening for transaldolase deficiency by measuring urinary polyols. In patients with transaldolase deficiency, monitoring of kidney function is mandatory.