Acute kidney failure occurring without other cause in a person with severe liver disease .

Causes, incidence, and risk factors

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 drastic reduction in blood flow to the kidneys. The kidney structure remains essentially normal and the kidneys often will instantly function 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 impending 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).

Signs and tests

Examination may reveal

hepatic encephalopathy , jaundice , ascites , and other signs of liver failure along with the decrease in kidney functioning. Deep tendon reflexes are increased and abnormal reflexes may be present, indicating damage to the nervous system. The abdomen is dull on examination by tapping with the tips of the fingers ( percussion ), often with a visible fluid wave when examined by touch ( palpation ). There may be increased breast tissue, decreased testicular size, lesions (spider telangiectasia) on the skin or other signs of liver failure. 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 (Note: 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

An

EEG may be performed if signs of hepatic encephalopathy are present

Treatment

Treatment is directed to improving liver function, if possible, and to ensuring that circulating blood volume and cardiac output (heart pumping action) are adequate. The disorder is generally treated in the same manner as kidney failure from any cause. All unnecessary drugs (particularly neomycin, NSAIDS and diuretics) are stopped. Dialysis may improve symptoms. There are medications such as octreotide, midodrine, and dopamine, which may be used as a temporary measure to improve kidney function. Surgical placement of a shunt from the abdominal space (peritoneum) to the jugular vein or superior vena cava (called a Levine shunt) may reduce ascites and reverse some of the symptoms of kidney failure.

Expectations (prognosis)

The probable outcome is poor. Death commonly occurs as a result of secondary infections or hemorrhage.

Complications

Secondary infections

Bleeding

Hepatic coma

End-stage renal disease

Fluid overload with subsequent

congestive heart failure or pulmonary (lung) edema

Damage and failure of multiple organ systems

Calling your health care provider

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