Table 1.
Biochemical serum and urine analysis of the proband at the age of diagnosis (20 years old) through to the age when she began peritoneal dialysis (25 years old)
| Exam (reference values) | Age (years) | |||||
|---|---|---|---|---|---|---|
| 20 | 21 | 22 | 23 | 24 | 25 | |
| Serum calcium (8.3–10.6 mg/dL) | 7.1 | 8.3 | 9.1 | 7.9 | 7.5 | 10.9 |
| Serum magnesium (1.3–2.7 mg/dL) | 0.9 | 1.3 | 1.2 | 1 | 0.9 | 0.9 |
| Uric Acid (2.6–6.0 mg/dL) | 7.5 | 7.5 | 11.9 | 11.8 | 12.2 | 13.1 |
| Creatinine (0.50–1.10 mg/dL) | 1.9 | 2.1 | 2.4 | 3.7 | 4.8 | 5.6 |
| iPTH (12–72 pg/mL) | 120 | 321 | 305 | 542 | 900 | 2620 |
| Urea (19–49 mg/dL) | 72 | 84 | 85 | 84 | 137 | 220 |
| FECa (<0.20) | 3.78 | 4.24 | 3.53 | 3.03 | 2.5 | 2.7 |
| FEMg (3–5) | 14.6 | 15.8 | 19.1 | 28.9 | 20.4 | 19.3 |
| Urinary pH (4.8–7.0) | 7 | 7 | 6.5 | 6 | 5 | 6.5 |
| Glomerular Filtration Rate (81–134 mL/min 1.73 m2) | 51 | 45 | 34 | 33 | 25 | 11 |
At the age of diagnosis, the patient presented high levels of uric acid, urea, and intact parathyroid hormone. At age 20, she presented stage 3, moderate chronic kidney disease (CKD). She presented high fractional excretion of calcium and magnesium. In six years, she progressed to end-stage kidney disease. Formulas: FECa (Ca(U) X Cr(S)/Ca(S) X Cr(U) X 100); FEMg (Mg(U) X Cr(S)/Mg(S) X Cr(U) X 100); Glomerular Filtration Rate: [140 – age (years) X weight (kg)/72 X Cr(S) (mg/dL) X 0.85 (female)]. Abbreviations: iPTH, intact parathyroid hormone; FECa, fractional excretion of calcium relative to creatinine; FEMg, fractional excretion of magnesium relative to creatinine; Ca, calcium; Mg, magnesium; U, urinary; S, serum; Cr, creatinine