Azotemia is a condition that occurs when your kidneys have been damaged by disease or an injury. You get it when your kidneys are no longer able to get rid of enough nitrogen waste.

Azotemia is usually diagnosed by using urine and blood tests. These tests will check your blood urea nitrogen (BUN) and creatinine levels.

Types

There are three types of azotemia:

  • Prerenal: Prerenal azotemia occurs when fluid isn’t flowing enough through the kidneys. This low flow of fluid creates high levels of concentration of serum creatinine and urea. This type of azotemia is the most common and can usually be reversed.
  • Intrinsic: Intrinsic azotemia usually occurs from infection, sepsis, or disease. The most common type of intrinsic azotemia or intrinsic renal failure is acute tubular necrosis.
  • Postrenal: A urinary tract obstruction causes postrenal azotemia or renal failure. Postrenal azotemia can also occur with prerenal azotemia.

These types of azotemia may have somewhat different treatments, causes, and outcomes. However, they each can lead to acute kidney injury. Azotemia can also lead to acute kidney failure if it’s left untreated or if it’s not discovered early.

Azotemia and uremia are two different types of kidney conditions. Azotemia is when there’s nitrogen in your blood. Uremia occurs when there’s urine in your blood. However, they’re both related to kidney disease or injury.

Many times, you won’t notice any symptoms of something being wrong with your kidneys, including azotemia, until a late stage. This late stage is usually when kidney failure has started.

The symptoms of azotemia may include:

  • acute renal failure (if azotemia continues to progress over a period of hours or days)
  • acute kidney injury
  • loss of energy
  • not wanting to participate in your usual activities
  • loss of appetite
  • fluid retention
  • nausea and vomiting

Nausea and vomiting are a sign that the disease has worsened.

The primary cause of azotemia is a loss of function of your kidneys. However, the different types of azotemia or renal failure have different causes:

  • when fluid flowing through the kidneys is not enough to remove the nitrogen (prerenal azotemia)
  • when the urinary tract is obstructed by something or by a rupture (postrenal azotemia)
  • infection or disease (intrinsic azotemia)
  • heart failure
  • complications of diabetes
  • some medications, particularly nephrotoxic drugs and high doses of steroids
  • advanced age
  • history of renal difficulties
  • heat exposure
  • severe burns
  • dehydration
  • lowered blood volume
  • some surgeries
  • an injury to the kidney

Cancer treatment can also sometimes cause azotemia. Chemotherapy drugs are powerful and can damage your kidneys. Your oncologist will monitor your kidneys with regular tests. If needed, your doctor may be able to adjust or try different chemotherapy medications if your kidneys are affected.

The treatment of azotemia depends on the type, cause, and what stage of progression it’s in. With this in mind, some of the treatments may include:

  • dialysis (for late-stage progression; may only be temporary)
  • iNOS (inducible nitric oxide synthase) inhibitors
  • delivery of the baby in the case of pregnancy
  • early treatment of postrenal azotemia
  • treatment of the underlying condition or disease
  • intravenous fluids
  • medications
  • changes in your eating habits

Those with kidney disease or other kidney issues can develop prerenal azotemia. Other complications may include:

Prerenal azotemia in pregnancy can cause acute kidney injury and jeopardize the health of the baby and the mother. If you’re pregnant and have a history of kidney disease, you should let your doctor know. You’ll want to have your kidney function tested periodically throughout your pregnancy.

If you have any symptoms of kidney disease or injury, you should see a medical professional immediately or call 911. It’s important that you schedule regular appointments with your doctor. During these checkups, your doctor will take routine blood and urine lab tests. These tests will help them find any issues with your kidneys early, before any outward symptoms are noticeable.

If caught early, many forms of azotemia are treatable and manageable. However, other health conditions and pregnancy can make treatment difficult.

Many people with azotemia have a good prognosis.

Complications, other health issues, and kidney disease or injury caught in late stages may make regular dialysis necessary. It’s important to note that azotemia that’s left untreated or has complications can result in death. For this reason, it’s important to see your doctor regularly.