Adenine phosphoribosyltransferase deficiency in the United Kingdom: two novel mutations and a cross-sectional survey.

Background: Adenine phosphoribosyltransferase deficiency is an inborn error of metabolism that can cause kidney disease from crystalline nephropathy or kidney stones.

Methods: We present three cases from a single centre with varied presentations to illustrate how increasing awareness led to better patient identification. We then undertook a cross-sectional survey of all the patients identified from the Purine Research Laboratory in the UK since 1974.

The impact of introducing thioguanine nucleotide monitoring into an inflammatory bowel disease clinic.

Background: Thioguanine nucleotides (TGNs) are the active product of thiopurine metabolism. Levels have been correlated with effective clinical response. Nonetheless, the value of TGN monitoring in clinical practice is debated.

HPRT deficiency: identification of twenty-four novel variants including an unusual deep intronic mutation.

Hypoxanthine phosphoribosyltranferase (HPRT) deficiency is an X-linked disorder of purine salvage that ranges phenotypically from hyperuricaemia to Lesch-Nyhan Syndrome. Molecular testing is necessary to identify female carriers within families as a prelude to prenatal diagnosis. During the period 1999-2010 the Purine Research Laboratory studied 106 patients from 68 different families.

Purine nucleoside phosphorylase deficiency: a mutation update.

Purine nucleoside phosphorylase (PNPase) deficiency is an autosomal recessive disorder affecting purine degradation and salvage pathways. Clinically, patients typically present with severe immunodeficiency, neurological dysfunction, and autoimmunity. Biochemically, PNPase deficiency may be suspected in the presence of hypouricemia.