Azotemia vs Uremia – Symptoms & Differences

Azotemia

It is a serious renal condition that is characterized by rapid heartbeat, low urine flow, vomiting and a variety of other problems.

In the United States, azotemia occurs in about 1% percent of all hospital admissions. It mainly affects the patients in the age group of 48 to 64 years.

Types

Post-Renal Azotemia

It is an excess of nitrogen in the blood that is caused by a blockage in the kidneys which prevents the urine from being excreted from the renal system.

Intrarenal Azotemia

Intrarenal azotemia, also known as acute kidney injury or acute renal failure, is attributed to problems with the kidney itself. Possible causes include:

  • diseases which may cause chronic renal failure – chronic analgesic abuse, pyelonephritis (inflammation of a part of the kidneys), and diabetes;
  • non-steroidal anti-inflammatory drugs (such as ibuprofen);
  • intravenous radiocontrast dye – these dyes may cause kidney problems;
  • angiotensin-converting enzyme inhibitors – these are medications which slow the activity of the enzyme ACE;
  • biologic therapies, like – Interferon Alfa or Interleukin-2;
  • chemotherapy drugs, like – Carboplatin, Cisplatin (used to treat ovarian cancer, prostate cancer, testicular cancer, breast cancer, pancreatic cancer, cervical cancer, head and neck cancer, bladder cancer, lung cancer, liver cancer, esophageal cancer, brain tumors, mesothelioma, and neuroblastoma), Mitomycin, Carmustine, high-dose Mithramycin, Methotrexate, and Streptozocin;
  • anti-fungal antibiotics (Amphotericin B);
  • drugs like Aminoglycoside antibiotics (including – Vancomycin or Gentamycin).

Prerenal Azotemia

Prerenal azotemia, also referred to as the prerenal failure, occurs when something that is affecting the blood circulation affects how the kidneys function. It is the most common cause of acute renal failure. Prerenal azotemia can be restored back to normal by facilitating a sufficient or normal amount of blood to the kidneys. Damage may occur to the kidney (acute tubular necrosis) if the cause is not fixed quickly.

Conditions which may lead to prerenal azotemia include:

  • blockage of the artery which supplies the kidney with blood;
  • burns;
  • shock;
  • dehydration;
  • heart failure;
  • heat exposure;
  • long-term diarrhea or vomiting;
  • hemorrhage.

Symptoms

Common symptoms may include:

  • nausea and vomiting;
  • acute renal failure;
  • fluid retention;
  • loss of appetite;
  • not wanting to participate in the usual activities;
  • loss of energy;
  • acute kidney injury.

Complications

People suffering from the condition are prone to damage of the kidneys and kidney failure (occurs when the kidneys suddenly become unable to filter waste products from the blood). Therefore, it is crucial to take timely steps for decreasing the risk of azotemia related complications.

Diagnosis

The diagnostic involves the following:

  • kidney imaging – your healthcare provider may order ultrasonography or X-rays of the kidneys to visualize any abnormalities within the kidneys;
  • 24-hour urine test – it checks the function of the kidneys and detects disease. During this test, a 24-hour sample of urine is obtained to measure the specific gravity, protein, osmolality, creatinine, and sodium concentrations to assess the condition of the kidneys;
  • kidney function test  – it measures the levels of BUN (blood urea nitrogen), chloride, serum uric acid, serum creatinine, potassium, sodium in kidney failure suferrers;
  • catheterization – during this procedure, a thin plastic tube is inserted into the urethra (a tube which connects the urinary bladder to the urinary meatus) to ease the urine flow to observe if there is any blockage;
  • physical exam – during this test, your healthcare professional will perform a physical exam to view the state of the kidneys;
  • medical history – information is gathered about current medications, any infections, diseases, and any family history of kidney disease.

Uremia

It a clinical condition that is described by metabolic abnormalities as well as an electrolyte, fluid, and hormone imbalances. In this condition, the level of the blood urea nitrogen is increased and can result from any disorder that hinders the excretion of urine from the body or which impairs the functioning of the kidneys.

Symptoms

It may cause you to have some of the following symptoms:

  • trouble concentrating;
  • extreme fatigue or tiredness;
  • vomiting;
  • nausea;
  • headache;
  • little or no appetite;
  • cramping in the legs.

Causes

Image credit – https://commons.wikimedia.org/wiki/File:Kidney_stones

Any condition that impairs the capacity of the kidneys to filter the waste products may result in uremia. Possible causes include:

  • excessive vomiting, diarrhea, or bleeding;
  • certain drugs, such as – nonsteroidal anti-inflammatory drugs that are given in excessive or high doses intravenous contrast material;
  • dehydration;
  • any trauma or injury to the kidney;
  • congestive heart failure;
  • burns;
  • certain medical conditions that cause a decrease in blood flow or blood volume;
  • surgery to the kidney;
  • embolism or occlusion of the renal artery that hinders the blood flow to the kidney;
  • anomalies of the kidneys;
  • failure of kidneys;
  • kidney stones;
  • diabetes;
  • hypertension (high blood pressure).

Risk Factors

Risk factors include:

  • excessive use of nonsteroidal anti-inflammatory medication;
  • kidney injury or trauma of any kind;
  • excessive bleeding;
  • autoimmune disease;
  • severe vomiting or diarrhea;
  • hypertension;
  • urine flow blockage;
  • hypotension;
  • infection;
  • diabetes;
  • shock;
  • kidney stones;
  • skin burns;
  • irregularities of a kidney;
  • dehydration;
  • congestive heart failure (a progressive disease that causes the heart to weaken);
  • recent surgery;
  • renal artery embolism.

Note – it is essential to note that not all people with the above conditions will deal with uremia.

Diagnosis

The diagnosis involves a specialized blood and urine tests which can help healthcare professionals to determine the number of waste products in the blood as well as how effectively are the kidneys functioning.

Treatment

The treatment requires hospitalization to correct the kidney filtration function.

Prevention

Since the condition is caused by kidney failure and severe kidney disease, you can prevent kidney disease by:

  • practicing regular physical exercise;
  • having a diet that is focused on fruits, veggies, and legumes;
  • controlling diabetes;
  • not smoking cigarettes and avoiding second-hand smoking;
  • taking steps to maintain cardiovascular health;
  • maintaining a healthy blood pressure.

Bottom Line – Azotemia vs Uremia

Azotemia is a condition which happens when the kidneys have been damaged by an injury or a disease. In this medical condition, there is an elevation of serum creatinine and blood urea nitrogen levels above normal values.

Uremia is the term for the clinical syndrome of renal failure with multisystemic problems, like – polydipsia, polyuria (an excessive large production or passage of urine), weight loss, vomiting, depression, and other sequelae of inadequate renal function and azotemia.

The two conditions can occur at the same time.

References

https://www.ncbi.nlm.nih.gov/pubmed/19566846
http://www.ijpediatrics.com/index.php/ijcp/article/viewFile/144/137
https://www.ncbi.nlm.nih.gov/pubmed/1270342