Asymptomatic CBD
stones may be found incidentally during evaluation of patients with suspected
gallstones. In fact, in non-jaundiced patients with normal ducts on
trans-abdominal ultrasound the prevalence of CBD stones at the time of
cholecystectomy is unlikely to exceed 5% (Collins et al., 2004).
Patients with choledocholithiasis may present
with biliary colic.
The pain is usually located in the right upper quadrant
and/or epigastrium and frequently radiates to the back and right scapula. The
intensity of the pain is often severe enough that patients often seek immediate
medical attention with the first episode. Classically, the pain of biliary
colic occurs following fatty meals, although this situation does not occur in
most cases. An association with meals is present in only 50% of patients, and
in these patients, the pain often develops more than 1 hour after eating. In
the remaining patients, the pain is not temporally related to meals and often
begins at nighttime waking the patient from sleep.The duration of pain is
typically 1 to 5 hours. The attacks rarely persist for more than 24 hours and
are rarely shorter than 1 hour. It is not possible to differentiate between
biliary colic due to cystic duct obstruction by gallbladder stones and biliary
colic caused by stones migrated to the bile duct. In fact, the term “biliary
colic” does not pretend to make such differentiation (Besselink
et al., 2009). Pain is likely to be caused by distension of the bile duct by
the offending stone(s) within the bile duct. The probability of stone retention
increases with increasing diameter of the stone(s) (Festi
et al., 1999).
Other presenting symptoms include
bilirubinuria (or tea-colored urine), pruritus, acholic stools, and jaundice.
However, the biliary obstruction usually is incomplete. There may be nausea and
vomiting with intermittent or constant epigastric or right upper quadrant (RUQ)
pain. Typically, the pain and jaundice associated with CBD stones are more
intermittent and transient than when the biliary obstruction is caused by a
malignancy (Nakeeb 2006).
Physical
examination of patients with choledocholithiasis may be normal or reveal
jaundice, scleral icterus, and abdominal tenderness over the right upper
quadrant without peritoneal signs. Early in the course, physical examination
may not be very different from that of patients with cholecystitis (Eisen
et al., 2001).
The
natural history of a given CBD stone is difficult to predict. In a prospective
study of 1000 patients with symptomatic gallstones, it was found that 73% of
cases that presented with features suggestive of CBD stones had no CBD stones
at time of operation, and were therefore considered to have passed the stone
spontaneously. However, cases of cholangitis or jaundice were less likely to
pass stones spontaneously (Tranter 2003). In another study,
the
frequency of unexpected bile duct stones in patients who have experienced
biliary colics varies between 5% and 12%.These data indicate that bile duct
stones are relatively rare in patients with biliary colics and/or that most
bile duct stones migrate spontaneously to the duodenum (Caddy et al.,
2006).
The clinical course may be complicated by acute gallstone
pancreatitis, cholangitis, or rarely, hepatic abscess. Also prolonged biliary obstruction can lead to biliary cirrhosis
and portal hypertension (Ko et al., 2002).
CBD stones are covered by a bacterial biofilm of adherent
quiescent bacteria residing in a hermetic environment. When stones cause
obstruction of the ducts, cytokines released by epithelial cells activate these
bacteria to the planktonic and virulent forms. Therefore, bile duct obstruction
secondary to stones often is accompanied by bacterial sepsis resulting from
activation of the bacterial biofilm on these stones. Sepsis is much less likely
to occur in the context of malignant obstruction without choledocholithiasis (Ko
et al., 2002).
The classical diagnostic presentation of cholangitis
is Charcot’s triad which includes: jaundice, right hypochondrial tenderness and
fever with chills. A consensus meeting was held in Tokyo in 2007 to define
diagnostic criteria of acute cholangitis. Some panelists proposed that history
of biliary disease should be included in the diagnostic criteria for acute
cholangitis (Mayumi
et al., 2007).
Table (1): diagnostic criteria for acute cholangitis (Mayumi et al., 2007).
A. Clinical context and clinical manifestations
|
1. History of biliary disease
2. Fever and/or chills
3. Jaundice
4. Abdominal pain (RUQ or upper abdominal)
|
B. Laboratory data
|
5. Evidence of inflammatory response[1]
6. Abnormal liver function tests[2]
|
C. Imaging findings
|
7. Biliary dilatation, or evidence of an etiology (stricture, stone,
stent, etc)
|
Suspected diagnosis:
|
Two or more items in A
|
Definite diagnosis:
|
·
Charcot’s
triad (2 + 3 + 4)
·
Two or more
items in A + both items in B + C
|
Gallstone
pancreatitis can develop from the obstruction of the ampulla of Vater by common
duct stones. CBD stones are responsible for up to 50% of all cases of
pancreatitis.The risk of persistent
ampullary obstruction increases with advanced patient age and stone size less
than 5 mm (Telem et al., 2009). Most patients with gallstone pancreatitis experience a mild
self-limited attack from which they recover within a few days; however, some
patients will progress to develop severe pancreatitis with peripancreatic
necrosis, infection, or pseudocyst formation. Severe tenderness may point to
acute gallstone pancreatitis (Eisen
et al., 2001). Persistent CBD stones may also increase acute
biliary pancreatitis mortality rate. Autopsy studies demonstrate CBD stones in
up to 60% of patients with mortality secondary to acute biliary pancreatitis
(Telem et al., 2009).
Some cases of
acute biliary pancreatitis are due to
the biliary microcrystals (microlithiasis). The pathogenesis of acute
pancreatitis produced by biliary crystals is unknown. It is probably related to
the temporary impaction or migration of very small stones or clusters of
crystals at the level of the ampulla of Vater. The mechanism of such
pancreatitis is presumably the same as that when “normal size” biliary stones
are impacted in the ampulla of Vater in the onset of the disease. However, most
of patients presented with this condition suffered from acute pancreatitis
classified in earlier litrautrue as so called “idiopathic” pancreatitis, as
they do not bear gallbladder sludge, gallbladder stones and they did not have
the history of cholecystectomy (Kohut
et al., 2002).
Finally, prolonged biliary obstruction can lead to biliary
cirrhosis. The average time for choledocholithiasis to lead to biliary
cirrhosis is about 5 years, depending on the extent of obstruction. Even with
cirrhosis, however, the obstruction should be relieved because some reversal of
portal hypertension and secondary biliary cirrhosis may be possible (Ko
et al., 2002).
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