A Better Kidney Measurement

Diagnosing kidney failure in liver disease patients with cirrhosis

(RxWiki News) In a new study, researchers argue that the current way for diagnosing kidney failure in patients with cirrhosis is not accurate enough. Their results show that measures used by the Acute Kidney Injury Network (AKIN) may offer more precise results.

Spanish researchers set out to see how well AKIN measures could predict kidney failure in patients with cirrhosis - scarring and damage to the liver from chronic liver disease.

They found that the AKIN measures were more sensitive to changes in levels of creatinine - a muscle product that the kidneys filter out of the body through urine. High levels of creatinine in a person's blood is a sign of kidney failure.

dailyRx Insight: Spotting kidney failure in patients with liver disease will save lives.

The risk of death is very high for liver disease patients with kidney failure. According to Mark Thursz, Vice-Secretary of the European Association for the Study of the Liver, "Defining more sensitive tests that help to identify patients at risk of [kidney] failure or death earlier is critical to enable us to intervene and ensure the patient has the best possible outcome."

Currently, kidney failure is defined as have blood creatinine levels higher than 1.5 mg/dL. However, AKIN measures consider kidney failure as an increase in blood creatinine that is at least 0.3 ml/dL.

In other words, AKIN measures look at significant changes in blood creatinine rather than setting a fixed mark.

In their study of 300 cirrhosis patients, the researchers found that patients had the lowest chance of survival if they met both the current kidney failure criteria (creatinine greater than or equal to 1.5 mg/dL) and the AKIN criteria (increase in creatinine greater than or equal to 0.3 ml/dL).

Of these patients, 58 percent died, compared to 29 percent of patients who had creatinine levels lower than 1.5 mg/dL.

When patients met the criteria for kidney failure according to the current stands, but not according to AKIN standards, their survival rate was 80 percent.

These findings show that the AKIN measures, used in combination with the current standards, are significantly more accurate in predicting the outcomes of patients with cirrhosis.

More accurate diagnoses hopefully will lead to improvements in care for liver disease patients who face a high risk of death.

It is estimated that 5%-10% of the United States population, or 15 million to 30 million people, suffer from cirrhosis of the liver. Cirrhosis results when healthy liver tissue is replaced by non-functioning fibrous scar tissue. Cirrhosis has many causes, but most commonly results from alcohol abuse, viral hepatitis (B and C), and fatty liver disease (from insulin resistance and drug injury). Various genetic and metabolic diseases can also cause cirrhosis (ex. Wilson's disease, hemochromatosis). The symptoms of cirrhosis are variable, but they all are a result of either the liver not functioning (bruising and bleeding, itching, hepatic encephalopathy) or blood flow being restricted from a damaged liver (ascites, fluid in the abdomen; enlarged spleen). Eventually other organ systems like the kidneys and immune system may fail. Diagnosis is made by a liver biopsy, but a number of abnormal blood tests can also be diagnostic. Treatment is first aimed at the underlying causes (ex. Stopping drinking, treating hepatitis, treating Wilson's disease), and then managing complications (draining ascites, treating hypertension and infections, dialysis). Liver transplant is highly effective for patients that qualify. 

Chronic kidney disease affects over 26 million people in the United States, with more being affected by instances of acute kidney disease. Kidney disease results when the kidneys gradually lose their ability to filter out waste products from the blood and maintain the proper balance of water, salts and proteins in the blood. Chronic kidney failure can be caused by a multitude of reasons, but is commonly seen in patients with high blood pressure and diabetes, as well as patients with autoimmune diseases. Acute kidney failure is similar to chronic kidney failure in that the kidneys fail to do their jobs, but it happens at a more rapid pace, usually due to loss of blood flow, toxic drugs, or obstruction of urine flow. Symptoms of kidney failure include feeling tired, muscle cramps, trouble sleeping, swollen feet and puffy eyes, and an increased need to urinate. Eventually many patients need replacement of the hormones erythropoietin and calcitriol, and sometimes dialysis and kidney transplantation Treatment includes medications like ACE inhibitors (Lotensin, Capoten, Vasotec) and ARBs (Cozaar, Diovan, Benicar) although they are not curative.. Diagnosis is made by measuring substances in the blood and urine.

The study's results were presented at the International Liver Congress.

Review Date: 
March 31, 2011