PSC is chronic
progressive liver disease whose cause and cure is unknown, advancing
toward cirrhosis and sometimes liver failure.
Primary Sclerosing Cholangitis is a disease primarily of the bile
ducts, both inside and outside the liver (the ducts of the gallbladder
and pancreas may also be involved) The walls of the bile ducts become
inflamed (cholangitis). The inflammation causes scarring and hardening
(fibrosis) that narrows the bile ducts. The bile is then unable
to drain through the ducts accumulating in the liver causing damage
to liver cells. Eventually, so much bile is accumulated, it seeps
into the bloodstream. As a result of this long term cell damage
the liver develops cirrhosis (hardening or fibrosis).
The exact cause of PSC is unknown. Researchers suggest that there
may be a connection to the immune system, but this is yet unproven.
PSC often starts between the ages of late teens
and 20s and 45 and 50's, and it occurs most often in men. It was
once considered a rare disease, but recent studies show it is more
common than previously thought. About 70% of the patients with PSC
also have an Inflammatory Bowel Disease (IBD), especially ulcerative
colitis in which the colon becomes inflamed and ulcerated. Researchers
again suggest that genetic factors may link PSC and ulcerative colitis.
PSC usually progresses very slowly. Initially there may be no symptoms
unless a blood test picks up for instance above normal ranges in
the blood of the liver enzyme levels called alkaline phosphatase.
When symptoms do develop, they may be intermittent or persistent.
Gradually, they may worsen. The symptoms are caused by two things:
the bile not draining properly through the bile ducts, and the liver
not doing its job. Bile ducts can become infected, causing chills,
fever and upper abdominal tenderness. Itching may occur when bile
seeps into the bloodstream. As the disease progresses, chronic fatigue,
loss of appetite, weight loss and jaundice (yellowing of skin and
eyes) may occur. Finally, in the advanced stages of cirrhosis, extensive
swelling can occur in the abdomen and feet. Liver failure may take
many years to develop.
Diagnosis is usually made by cholangiography, an x-ray called ERCP
that involves injecting dye into the bile ducts. The test is performed
under sedation. A lighted, flexible endoscope is inserted through
the mouth, stomach and then into the small intestine. A thin tube
is place through the scope into the bile ducts, and the dye is injected
to highlight the bile ducts on the x-ray. If there is narrowing
of the bile ducts, the diagnosis of PSC is confirmed.
As the disease progresses, a liver biopsy is usually
needed to determine how much damage has occurred. Under local anesthesia,
a slender needle is inserted through the right lower chest to extract
a small piece of liver for microscopic analysis.
Although the disease is slow in progressing it varies from one person
to another, often liver transplantation is the only therapeutic
option for patients with end stage liver disease resulting from
this disorder, but there is increased risk of stomach cancer and
more aggressive IBD including Ulcerative Colitis with no guarantee
that the PSC won’t attack the new liver.
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