Vascular Diseases of the Kidney
Regular and appropriate blood supply to the glomerular capillary network is essential for the proper function of the kidneys. If the blood supply to the kidney is hampered, there is fluid and salt disturbance in the body.
Vascular diseases of the kidney are:
- 1. Atherosclerosis
- 2. Hypertensive disease
- 3. Embolic diseases
- 4. Inflammatory diseases
- 5. Hematologic disorders.
Thromboembolic diseases of the Kidney
- Thromboembolic diseases of the kiidney occur due to embolization of thrombus formed in any artery or the left ventricle.
- Thrombosis of major renal arteries or their branches may be due to trauma, atherosclerosis, arteritis.
- Emboli may also commonly originate in the left ventricle as in AMI, bacterial endocarditis, non-infective endocarditis.
- There is flank pain, tenderness, fever, hematuria, leukocytosis, nausea, vomiting.
- Lab findings are increased AST, LDH, alkaline phosphatase.
- There is acute oliguria, hypertension. Diagnosis is by renal arteriography.
- · Surgical intervention
- · Anticoagulant therapy
- · Supportive therapy
- · Antihypertensives.
Atheroembolic disease of Renal arteries
- It is a part of systemic syndrome due to atherosclerotic plaques in aorta and other arteries.
- The atherosclerotic plaques embolise to the renal arteries and small arteries of the kidneys.
- It is common in the elderly.
- Clinical manifestations appear 1 day to 2 weeks after the embolization.
- There is fever, myalgia, headache, and weight loss. There may be purple toes, gangrene of toe, and embolization to other parts, hypertension, renal insuffi-” ciency, oliguria and renal failure.
- Dialysis, cholesterol-lowering agents, angiography, angioplasty of blocked vessels.
Renal vein thrombosis
- Thrombosis of one or both renal veins may occur in a patient of nephrotic syndrome, membranous glomerulopathy, carcinomas etc.
- There is proteinuria, fever, chills, tenderness in lumbar region, leucocytocsis, hematuria, deterioration in renal function, hypertension, Fanconi-like syndrome.
- Diagnosis is by angiography, Doppler ultrasound, CT, M RI.
- Anticoag u lation Streptokinase Nephrectomy Thrombectomy.
Renal artery stenosis (RAS)
- It is also called ischemic renal disease and it may be a part of end-stage renal disease in patients of uremia over 50 years of age.
- RAS may be the cause of hypertension in 5% of hypertensives.
- There is an atheromatous plaque at the origin of the renal artery.
- . Bilateral RAS may also be found, especially in elderly, hypertension, diabetes, atherosclerosis.
- There may be intrinsic structural abnormalities of the arterial wall especially in young women. This condi~ tion is called fibromuscular dysplasia.
- Diagnosis is by Doppler ultrasonography, ultrasound of kidneys, contrast angiography, intra-arterial digital subtraction angiography.
- ACE inhibitors with 99m Tc labeled DTPA or 99m Tc labeled MAG 3 renography, gadolinium 3D MR angiography are new and very sensitive and specific tests.
- Angioplasty of affected renal artery Angioplasty with stenting.
- In patients of hypertension, there is renal arteriolar disease which leads to loss of nephron function called nephrosclerosis.
- Nephrosclerosis may be benign or malignant.
Benign arteriolar nephrosclerosis
- In hypertensives with blood pressure> 150/ 90 mm Hg, especially in the early stages, the kidney size may be normal or reduced and the renal arteries may show atherosclerotic changes.
- The afferent arterioles are thick, with narrow lumens, with ischemic injury of glomeruli and tubules.
- On fundoscopy, there is narrowing of retinal arteries, and flame-shaped haemorrhages.
- There is cardiac hypertrophy and congestive heart failure.
- . Serum creatinine is raised and there is mild proteinuria.
- The GFR (Glomerular Filtration Rate) is normal.
Malignant arteriolar nephrosclerosis
- In long-standing hypertension, there may be a sudden accelerated elevation of blood pressure with diastolic blood pressure sometimes more than 130 mmHg, with papilledema, CNS manifestations, heart failure, and renal insufficiency.
- The kidneys are full of haemorrhages and have a characteristic flea-bitten appearance (diffuse red spots).
- There is fibrinoid necorsis, thickening of vessel walls and necrotizing arteriolitis.
- Usually malignant hypertension occurs in the 3rd or 4thdecade.
- It is more common in men.
- There is giddiness, headache, blurring of vision, seizures, and altered consciousness.
- There may be heart failure and renal failure.
- Lab findings are increased serum creatinine, hematuria, prQ,teinuria, RBC and WBC casts in urine, hypokalemia, metabolic alkalosis, hemolytic anaemia and uraemia-.
- Control of hypertension Management of uraemia.