Dr.S.Venkatesan MD

The much fancied criteria   “suspect secondary  HT” if the  onset of  hypertension  is   before 30 years   later than  55  years ,may be useful  .But a caution about this criteria  : It does not mean you should not hesitate to  diagnose renal HT  between 30 -55 years.  The  real onset may be   < 30years , but  the patient may report to the physician  late  in his /her  40 or 50s !

1. Diastolic blood pressure > 120
2. Sudden acceleration blood pressure
3. Blood pressure which is  resistant to control with three or 4 drugs ,that shall typically include a  diuretic.
4. An episode of left ventricular failure (Often referred to as  called flash pulmonary edema)
5. Presence of  Hypertensive retinopathy
6. Para umbilical bruit
7. HT associated with significant CAD
8. Marked LVH in echocardiography
9. Finally , most importantly , worsening of renal function with ACE inhibitor is a  strong clue the kidney is under perfused  and  the   renal circulation  is dependent on  elevated angiotenisn 2 (Which ,if blocked worsens the GFR ).This implies every physician should take a baseline serum creatinine  and urea before starting them on ACEI.(Which is rarely followed , as far as my country is concerned !)

Is there any simple way to  differentiate  reno vascular from renal parenchymal HT ?

It is very difficult to differentiate between these two clinically. It makes things more difficult , as  combination of both occurs. Prolonged renal ischemia can result in parenchymal damage as well.

The simplest way is to do a rapid ultrasound imaging to assess kidney size and texture (Loss of cortical-medullary differentiation indicating early renal contraction phase ).Of course , our nephrology colleagues are always there to help you out .

* It need to be remembered the functional renal HT -Renal tubular acidosis,  Adrenal HT (Conn’s /chromo-pheocytomas  has to be ruled out , as these entities also occur in the same age group ).The combination of hypokalemia and mild alkalosis is a  good clue to rule out many of these  defects.

* The CT scan image used in the above illustration  courtesy

http://www.ajronline.org/cgi/content-nw/full/189/3/528/FIG21