Secondary hypertension can account for 15% of hypertension cases. The causes of secondary hypertension mostly come from renal diseases, such as renal parenchymal or renovascular disease, and endocrine diseases. The importance of diagnosing secondary hypertension lies in the fact that it may convert an incurable disease into a potentially curable disease. Even if the underlying disease may not be curable, being able to offer disease specific treatments may often make blood pressure control much easier. The causes of endocrine hypertension include primary aldosteronism, pheochromocytoma, Cushing's syndrome, acromegaly, hyper-or hypothyroidism, hyperparathyroidism and other mineralocorticoid hypertension (e.g. apparent mineralocorticoid e...