Hepatorenal syndrome

Definition

Hepatorenal syndrome is acute kidney failure that occurs with no cause in a person with severe liver disease.

Causes

Hepatorenal syndrome occurs when there is a decrease in kidney function in a person with a liver disorder. The most common symptom is decreased urine production. As a result of reduced elimination of urine, nitrogen-containing waste products accumulate in the blood stream (azotemia).

The exact cause of hepatorenal syndrome is unknown. For some reason, there is severe reduction in blood flow to the kidneys. The structure of the kidney remains basically normal, and the kidneys will often function instantly well if the liver disease is corrected (for example, by liver transplantation).

The disorder occurs in up to 10% of patients hospitalized with liver failure. It may be a sign of approaching death, caused by the accumulated effects of liver damage and kidney failure, in people with acute liver failure, cirrhosis, or alcoholic hepatitis. It is diagnosed when other causes of kidney failure are ruled out.

Risk factors include cirrhosis, alcoholic hepatitis, acute liver failure, recent abdominal paracentesis, infection, gastrointestinal bleeding, use of diuretics, and the presence of orthostatic hypotension (blood pressure which falls when the person rises or suddenly changes position).

Symptoms

• Decreased urine production
• Dark-colored urine
• Yellow skin
• Weight gain  
• Abdominal swelling
• Change in mental status
  • Dementia
  • Delirium
  • Confusion
• Coarse muscle movements, jerking
• Nausea and vomiting

Exams and Tests

A physical examination will not directly reveal kidney failure. However, the exam will usually show signs of chronic liver disease -- hepatic encephalopathy, jaundice, ascites

The following may indicate kidney failure:

• Absent or low urine production, less than 400 cc/day
• Very low urine sodium concentration
• Increased urine specific gravity and osmolality
• Low serum sodium
• Fluid retention in the abdomen or extremities
• Increased BUN and creatinine levels (in people with liver disease, the BUN and creatinine levels underestimate the severity of kidney dysfunction)

The following may indicate liver failure:

• Low serum albumin
• Abnormal PT
• Increased ammonia levels
• Paracentesis with ascites
• Signs of hepatic encephalopathy (an EEG may be performed if such signs are present)

Treatment

Treatment is aimed at improving liver function, and ensuring that the amount of blood in the body and the heart pumping action are adequate. The disorder is generally treated in the same manner as kidney failure from any other cause. All unnecessary medicines are stopped. This is especially true for the antibiotic neomycin, NSAIDS (pain relievers such as ibuprofen)  and diuretics ("water pills"). Dialysis may improve symptoms. There are medications such as octreotide, albumin, and dopamine, which may be used as a temporary measure to improve kidney function.

Surgical placement of a shunt (called a Levine shunt) from the abdominal space (peritoneum) to the jugular vein may reduce ascites and reverse some of the symptoms of kidney failure. However, surgical shunts are rarely placed, because severe liver disease makes surgery very risky. A non-surgical shunt (known as TIPS) may be tried in some patients.

Outlook (Prognosis)

The predicted outcome is poor. Death usually occurs as a result of secondary infections or hemorrhage.

Possible Complications

• Secondary infections
• Bleeding
• Hepatic coma
• End-stage kidney disease
• Fluid overload with subsequent congestive heart failure or pulmonary edema
• Damage and failure of multiple organ systems

When to Contact a Medical Professional

This disorder most often is diagnosed in the hospital during treatment for a liver disorder.