[Prevalence of true resistant hypertension among uncontrolled hypertensive patients referred to a tertiary health care center]. 
Estimate the prevalence of resistant hypertension (rHTN) in uncontrolled hypertensive treated patients referred to a tertiary care center specialized for hypertension management.  The study was prospective observational.  Between January 2013 and April 2015, we recruited hypertensive treated patients, 18years age or older, under antihypertensive drugs since at least 12months, and referred to the hypertension unit of Tizi-ouzou university hospital for uncontrolled hypertension.  rHTn was defined as an office blood pressure≥140mmHg despite a triple therapy including renin angiotensin system blockers, calcium antagonists and diuretics at optimal doses, since at least 4weeks.  We screened 2367 patients with a mean age of 61.1±11.2years and 64.2% of men.  Eight hundred forty-three (35.6%) patients had suboptimal treatment, 364 (15.4%) a poor adherence to treatment and 202 (8.5%) a white-coat effect.  An excessive salt intake and a drug-related hypertension were identified in 281 (11.9%) and 36 (1.5%) patients, respectively.  A secondary cause of hypertension was diagnosed in 468 (19.8%) subjects.  Finally, only 173 patients showed a true rHTN requiring four drugs or more and its prevalence was 7.3% (CI 95%: 6.3-8.3).  Less than one patient from ten referred in our center for uncontrolled hypertension had a true rHTN, and more than fifty percent of patients had pseudo-resistance.  Most of patients with seemingly rHTN can reach blood pressure target provided they undergo thorough work up and care by a specialized team.