How kidneys increase blood pressure
The kidneys constantly monitor the blood flow within them. If blood supply decreases, they perceive this as a drop in pressure throughout the body and trigger a hormonal cascade that constricts blood vessels and retains sodium and water. The pressure is rising.
The problem is that when the renal artery is narrowed or when the kidney tissue is damaged, this mechanism works idle: the body as a whole does not need increased pressure, but the kidney continues to require it. Persistent hypertension develops that responds poorly to conventional treatment.
- Renovascular form - narrowing of the renal artery; the kidney does not receive enough blood
- Renoparenchymatous form - damage to the renal tissue itself: glomerulonephritis, diabetic nephropathy, chronic pyelonephritis, polycystic disease, reflux nephropathy
- Mixed options
Urological reasons
- Reflux nephropathy - scars in the kidney after childhood pyelonephritis against the background of vesicoureteral reflux; common cause of hypertension in young people
- Hydronephrosis and long-term urinary tract obstruction
- Shriveled kidney after illness or injury
- Consequences of kidney injury - hypertension may appear months later
- Polycystic kidney disease
- Large cyst compressing kidney tissue
- Kidney tumors, including those that produce hormones
- Nephroptosis with tension of the vascular pedicle in a vertical position
- Renal vascular abnormalities, including fibromuscular dysplasia - common in young women
- Atherosclerosis of the renal arteries is the main cause in the elderly
When to be suspicious
- Hypertension first appeared before the age of 30 or, conversely, after 55
- Blood pressure is poorly controlled on three or more medications in adequate doses
- Previously well-controlled blood pressure suddenly became high
- Crisis course with episodes of pulmonary edema
- Creatinine increased noticeably after starting to take certain groups of blood pressure medications
- On ultrasound, one kidney is noticeably smaller than the other
- There are changes in urine tests: protein, red blood cells
- In childhood there were repeated pyelonephritis
- There has been a kidney injury or surgery on the urinary tract
- Common atherosclerosis of other localizations
Diagnostics
- 24-hour blood pressure monitoring
- Urinalysis, daily protein, albumin/creatinine ratio
- Creatinine with GFR calculation, electrolytes
- Ultrasound of the kidneys - size, structure, difference between the kidneys, signs of hydronephrosis and cysts
- Ultrasound of the renal arteries - screening for stenosis
- CT angiography or MR angiography of the renal arteries
- Dynamic nephroscintigraphy - separate assessment of renal function
- Void cystography for suspected reflux
- Hormonal studies to exclude other secondary causes of hypertension
- Kidney biopsy for suspected glomerulonephritis
- Fundus examination and echocardiography to assess target organ damage
Treatment
- Elimination of urological causes: removal of stones and restoration of urine outflow, correction of hydronephrosis, treatment of reflux
- Puncture or excision of a large cyst compressing the kidney
- Nephropexy with a proven connection between hypertension and nephroptosis
- Stenting or angioplasty of the renal artery for stenosis - according to the decision of a vascular specialist
- Nephrectomy for a completely shriveled, non-functioning kidney that is a source of hypertension
- Drug therapy, selected taking into account the condition of the kidneys, is prescribed by a cardiologist or nephrologist
- Strict salt restriction
- Weight loss, smoking cessation, lipid control
- Treatment of underlying kidney disease
Observation
- Regular self-monitoring of blood pressure with keeping a diary
- Periodic monitoring of creatinine and urine analysis
- Control ultrasound of the kidneys
- Assessment of the condition of target organs: heart, fundus, blood vessels
- Caution with painkillers
- Limiting salt on an ongoing basis
- Check with your doctor about any new medications—some increase blood pressure and worsen kidney function
Where to get examined in Tashkent
Examination for suspected renal origin of hypertension includes ultrasound and Doppler ultrasound of the renal arteries, assessment of renal function and search for urological causes.
In Tashkent, such an examination is carried out at the UROLOGIC COMPLEX medical center and at the Tashkent Medical Park clinic, and further management is carried out jointly with a cardiologist and nephrologist.
If your blood pressure does not drop well despite several medications, and you are under thirty or over fifty-five, discuss a kidney examination with your doctor. This is the situation where the found cause really changes the outcome. Clinic contacts are below.
