Serum norepinephrine, epinephrine, metanephrine and
normetanephrine levels studied for hypertension aetiology were within normal limits.
For lipids, metanephrine,
normetanephrine, or hemoglobin A1c, there were no differences between the groups.
Blood adrenaline, noradrenaline, metanephrine,
normetanephrine and adrenocorticotropic hormone levels were also normal.
Measurement of plasma free metanephrine and
normetanephrine or 24-h urinary fractionated metanephrines are considered to be the most accurate biochemical tests for pheochromocytoma (4).
Plasma metanephrine levels were normal-to-mildly elevated [metanephrine 0.30 (reference value: 0-0.46 nmol/L);
normetanephrine 1.06 (0-0.98 nmol/L); epinephrine 0.73 (0-0.46 nmol/L); norepinephrine 4.45 (0-2.48 nmol/L); domapine <0.2 (0-0.55 nmol/L)].
To exclude pheochromocytoma as a cause of secondary hypertension, 24-h urine metanephrine and
normetanephrine levels were measured and were found to be normal.
The 24-hour urine
normetanephrine level was 141 881 nmol/24 hours.
Preoperative LDH measurement was 422 U/L, VMA was 1.93 mg/day,
normetanephrine was 255.5 [micro]g/24 h, metanephrine was 60.9 [micro]g/24 h, and cortisone was 2.03 [micro]g/dL.
Three years post-resection, a routine endocrinological surveillance test detected elevated urine norepinephrine,
normetanephrine and dopamine.
Biochemical tests performed prior to surgery suggested no sign of pheochromocytoma with normal metanephrine,
normetanephrine, and dopamine levels.
Plasma metanephrine and
normetanephrine levels were checked and were within normal limits.
Abdominal MRI and elevated urinary methylated metabolites of catecholamines (Metanephrine = 3.2 [micro]mol / 24h (normal range (NR) 0.2 to 1),
Normetanephrine = 47.5 [micro]mol / 24 h (NR: 0.4 to 2.1)) confirmed the diagnosis of catecholamine-secreting retroperitoneal PG.
