Elevated inflammation markers in pheochromocytoma compared to other forms of hypertension.

Objective: To investigate the effect of long-term catecholamine excess in pheochromocytoma on leukocyte and platelet count and on proteins of acute-phase response.

Methods: Fifteen subjects with pheochromocytoma, 16 with primary aldosteronism, 18 with essential hypertension and 17 healthy controls were studied. Sixteen subjects with pheochromocytoma were investigated after tumor removal. Leukocyte, neutrophil and platelet count, as well as C-reactive protein were measured in all subjects, while fibrinogen, alpha(1)-antitrypsin, alpha(2)-macroglobulin, orosomucoid, transferrin and prealbumin were only measured in subjects with pheochromocytoma, primary aldosteronism and essential hypertension.

Results: Subjects with pheochromocytoma showed significantly higher leukocyte [7.5 +/- 0.9 10(9)/l, p < 0.001 vs. primary aldosteronism (5.4 +/- 0.9 10(9)/l) and healthy controls (5 +/- 0.9 10(9)/l), p = 0.04 vs. essential hypertension (6.3 +/- 1.6 10(9)/l)], neutrophil (p < 0.001 vs. primary aldosteronism and healthy subjects) and platelet counts (p < 0.001 vs. primary aldosteronism; p = 0.01 vs. essential hypertension) compared to the other groups of subjects. Similar results were obtained for positive proteins of acute-phase response in subjects with pheochromocytoma [C-reactive protein: 0.62 +/- 0.52 mg/dl, p < 0.001 vs. healthy subjects (0.08 +/- 0.08 mg/dl), p = 0.001 vs. primary aldosteronism (0.17 +/- 0.19 mg/dl), p = 0.04 vs. essential hypertension (0.31 +/- 0.26 mg/dl); fibrinogen: p = 0.02 vs. primary aldosteronism; orosomucoid: p = 0.005 vs. primary aldosteronism; alpha(2)-macroglobulin: p = 0.009 vs. primary aldosteronism]. No significant differences were found in plasma levels of alpha(1)-antitrypsin, transferrin and prealbumin. Tumor removal led to a significant decrease in leukocyte (p = 0.004), neutrophil (p = 0.007) and platelet count (p = 0.003) and also to a significant decrease in acute-phase proteins (C-reactive protein: p = 0.03, fibrinogen: p = 0.008, alpha(1)-antitrypsin: p = 0.003, orosomucoid: p = 0.04).

Conclusions: Chronic catecholamine excess in pheochromocytoma is accompanied by an increase in inflammation markers which was reversed by the tumor removal.