Table 1 Biochemical and molecular parameters of 4 patients
From: Uric acid, an important screening tool to detect inborn errors of metabolism: a case series
Patient 1 | Patient 2 | Patient 3 | Patient 4 | |
|---|---|---|---|---|
Profile | Hypouricaemic hypouricosuria | Hypouricaemic hypouricosuria | Hyperuricaemic hyperuricosuria | Hypouricaemic hyperuricosuria |
Serum uric acid (μmol/l) | 50 (119–428) | 45 (119–428) | 525 (119–428) | 97 (119–428) |
Urine uric acid: creatinine (mmol/mmol) | 0. 001 (0.5–1.40) | 0. 01 (0.7–1.50) | 2.22 (0.4–1.1) | |
Fractional excretion of uric acid (%) | 1.8 (15–22) | 0.48 (15–22) | 16 (15–22) | 33 (15–22) |
Xanthine: creatinine (mmol/mmol) | 0.33 (<0.1) | 1. 45 (<0.1) | ||
Hypoxanthine: creatinine (mmol/mmol) | 0. 04 (<0.01) | 0.104 (<0.01) | ||
Sulfocysteine: creatinine (μmol/mmol) | 188.9 (0–10) | |||
Enzyme assay | Undetectable hypoxanthine–guanine phosphoribosyl transferase | |||
Genetic analysis | HPRT1 gene HPRT1 c.402+1G>A (IVS5+1G>A) | SLC22A12 gene revealed missense heterozygous transitions p.T467M | ||
Diagnosis | Xanthinuria type I or II | Molybdenum cofactor deficiency | Lesch–Nyhan disease | Renal hypouricaemia type 1 |