[Rational diagnostic approach in hypertension]

The list of causes of hypertension is quite long. However, the diagnostic procedure for detection of such forms should take in account the fact that the cause of nearly 95% of the cases with high blood pressure is unknown, i.e. primary or essential. The most often form of secondary hypertension is seen in patients with chronic renal disease, whereas renovascular, endocrine, cardiovascular or neurologic disorders all show a prevalence of less than 1%. Careful anamnestic evaluation and clinical examination combined with few simple laboratory tests allow the detection of most cases with secondary hypertension. Diagnosis of renovascular hypertension may require a more expended work up which, however, should only be performed in case of clinical suspect. Furthermore, the procedure in case of suspected endocrine disorders is of high clinical relevance, since hormonal analysis and/or radiologic examinations may be very expensive.