Pentosuria

Pentosuria is an inborn error of metabolism which is characterized by the excretion of 1 to 4 g of the pentose L-xylulose in the urine per day.

Epidemiology

The condition occurs essentially in Ashkenazi Jews with an estimated incidence of the heterozygote mutation of 1/79.

Clinical description

Pentosuria is benign and shows no symptoms. The sole biological feature is the constant excretion of L-xylulose in the urine that may be mistaken with glycosuria.

Etiology

It is due to mutations in the DCXR gene on chromosome 17 that codes for L-xylulose reductase (or L-xylitol dehydrogenase), an enzyme that catalyzes the conversion of 1-xylulose into xylitol.

Genetic counseling

Transmission is autosomal recessive.