Renal tubules are important delicate structures in the kidney. They participate in formation of urine as well as clearance of waste products from the body. Renal tubular damage causes acute tubular necrosis. In necrosis, the cells of the tissue become dysfunctional or they die. Thus renal tubular damage can lead to a condition called acute renal failure.
Renal tubular necrosis occurs due to several causes, but primarily the cause is insufficient blood supply to the kidney tissue. This means, there is lack of oxygen supply too and without oxygen, the tubule cells die.Acute tubular necrosis also occurs as a complication of various conditions which are associated with marked hypotension, severe water and salt depletion.
In other cases, renal tubule damage can develop as a consequence of incompatible blood transfusion or as a result of acute hemolytic crisis. It is also occasionally seen in patients suffering from obstructive jaundice or hepatocellular jaundice, severe infection and septicemia. Recent major surgery or traumatic injury damaging major muscle mass in the body can lead to renal tubular necrosis.
Certain drugs are also capable of producing acute renal failure, example aminoglycosides and other antibiotics.Certain poisons can also cause damage to the renal tubules.
Symptoms Of Renal Tubular Damage
- Initially the urine output is greatly reduced to 200 to 500ml/24 hours. This phase is called oliguric phase. There may be complete stoppage of urine known as anuria.
- There may be swelling all over the body, on face, legs etc.
- Nausea, vomiting, anorexia are common features.
- Patient becomes easily fatigued and lethargic.
- There may be abdominal pain.
- Patient complains of metallic taste in mouth.
- As the condition worsens, patient becomes confused. Muscular twitching, seizures, drowsiness, coma, and bleeding episodes occur.
At this stage the main dangers to life are:
- Pulmonary edema (collection of fluid in lungs).
- Potassium intoxication due to rise of potassium level in the blood. Especially if there is massive damage to the muscles and soft tissue as seen in traumatic injuries.
- Occurrence of severe infection.
- Rise of blood urea and creatinine.
Treatment Of Acute Tubular Necrosis
Since it is possible, in most cases, to reverse acute renal tubular necrosis, the underlying disease should be treated urgently. The view is to prevent and minimize the renal tubule damage that may lead to complication of acute renal failure.
The main criterion of treatment is to prevent excess buildup of fluid and waste in the body. At the same time give time to kidneys to heal.
- Identifying the cause and treating it.
- Restriction of fluid intake proportionately to its output.
- Medications to control potassium levels.
- Use of diuretic medicine to increase the amount of fluid output.
- Lastly kidney dialysis is life saving when all other measures fail. It can remove the excess of waste and fluid easily.
Indications for dialysis include; confusion and pre coma stage rise in potassium level, lack of urine production, raised urea and creatinin level and fluid buildup in the body.
Certain preventive measures can help to decrease the chance of renal tubular damage.
- Treat urgently conditions that are responsible for decreasing the blood flow to kidney or oxygen supply to the kidney. This reduces the risk of damaging the renal tubules.
- Always transfuse cross-matched blood to reduce the chance of transfusion reaction.
- Treat and control diabetes, liver disorders.
- Monitor carefully urine output when taking certain medicines.
- Drink enough fluids after any tests where contrast dye is used. This will aid in expelling excess of dye circulating in the system.