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Updated: Jul 18, 2026
13:13
Biochemical Measurement of Neonatal Hypoxia
Published on: August 24, 2011
Partial hypoxanthine-guanine phosphoribosyl transferase deficiency without elevated urinary hypoxanthine excretion
C M L van Dael1, L J W M Pierik, D J Reijngoud
1Section of Pediatric Nephrology, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, PO Box 30001, 9700 RB Groningen, The Netherlands. c.m.l.van.dael@bkk.umcg.nl
Molecular Genetics and Metabolism
|November 30, 2006
Summary
Partial hypoxanthine-guanine phosphoribosyl transferase (HGPRT) deficiency can cause neurological and kidney problems. This case highlights that normal blood uric acid and urinary hypoxanthine levels do not rule out partial HGPRT deficiency.
Area of Science:
- Biochemistry
- Genetics
- Pediatrics
Background:
- Partial hypoxanthine-guanine phosphoribosyl transferase (HGPRT) deficiency, or Kelley-Seegmiller syndrome, is linked to neurological symptoms and renal issues.
- Typical biochemical markers include elevated blood uric acid, increased urinary uric acid and hypoxanthine, and reduced HGPRT enzyme activity.
Observation:
- A boy with normal development experienced recurrent acute renal failure.
- Elevated urinary uric acid excretion occurred between renal attacks, with normal blood uric acid and urinary hypoxanthine levels.
- Significantly decreased HGPRT activity was detected in erythrocytes, leukocytes, and fibroblasts.
Findings:
- This case demonstrates that normal blood uric acid and urinary hypoxanthine levels do not exclude partial HGPRT deficiency.
- The biochemical presentation can vary, challenging traditional diagnostic criteria.
Implications:
- Clinicians should consider partial HGPRT deficiency even with seemingly normal biochemical markers.
- Early diagnosis and management are crucial for preventing severe neurological and renal complications.
- Further research into atypical presentations of HGPRT deficiency is warranted.
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