Two families with compound heterozygosity for adenine phosphoribosyltransferase deficiency

• Published in: Pediatric nephrology (Berlin, West) West), 2010-06, Vol.25 (6), p.1173-1176
• Main Authors: Iwaki, Takuma, Kusaka, Takashi, Ohashi, Ikuko, Nishida, Tomoko, Imai, Tadashi, Itoh, Susumu
• Format: Article
• Language: English
• Subjects: Adenine Phosphoribosyltransferase - deficiency; Adenine Phosphoribosyltransferase - genetics; Brief Report; Child, Preschool; Enzymes; Female; Gene mutations; Genetic screening; Heterozygote; Humans; Infant; Kidney Failure, Chronic - genetics; Male; Medicine; Medicine & Public Health; Mutation; Nephrology; Pediatrics; Pedigree; Purines; Urology
• ISSN: 0931-041X; 1432-198X
• DOI: 10.1007/s00467-009-1430-4

Adenine phosphoribosyltransferase deficiency is a disorder in which 2,8-dihydroxyadenine (2,8-DHA) crystalluria is caused by a congenital deficiency in the enzyme adenine phosphoribosyltransferase (APRT). In most cases, APRT deficiency is caused by autosomal recessive inheritance of a homozygote of the mutant gene APRT*Q0 or APRT*J, but there are also some cases in which the disorder is caused by the compound heterozygote APRT*Q0 and APRT*J. In the patients described here, brown round crystals were found in their urinary sediment. Crystalluria was the first sign of APRT deficiency, thereafter confirmed by genetic screening for APRT*/Q0 and APRT*. We performed genetic screening for APRT*Q0 and APRT*J in two families and diagnosed three cases of APRT*Q0 /APRT*J compound heterozygote-type APRT deficiency. Genetic screening for APRT*Q0 and APRT*J of family members is effective for early diagnosis and early treatment for family members.