Læknablaðið : fylgirit - 01.08.1978, Page 14

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4. The aim. of medical treatment is to
reverse this metabolic abnormality by
stimulating the liver to secrete „good“
bile, which is unsaturated in cholesterol
instead of ,,bad“ or supersaturated
bile which led to the formation of the
stones in the first place.
5. Both CDCA and UDCA probably act in
the same way — by inhibiting hepatic
cholesterol synthesis and by reducing
biliary cholesterol secretion.
SELECTION BASED ON SYMPTOMS
ALONE (WITHOUT X-RAYS)
Even though patients may have typical
symptoms of gallstones such as pain
suggestive of biliary colic or fat intole-
rance, belching, abdominal discomfort or
distention, CDCA should not be given
until the presence of gallstones has been
proven, usually by oral cholecystography.
Experience in some European countries
has shown that family practitioners tend to
prescribe CDCA for non-specific dyspepsia
on the assumption that if antacids and
cimetidine have not worked, the problem
must be due to gallstones so why not trv
CDCA? Even though the results of un-
controlled trials have suggested that in
patients with gallstones, CDCA reduces
both the frequency and severity of non-
specific dyspeptic symptoms and biliary
colic (the mechanism for this apparent
improvement is unknown), it seems un-
wise, at present, to recommend CDCA for
the treatment of ,,biliary“ symptoms
alone.
SELECTION BASED ON X-RAYS
I Gallbladder function
We now know that treatment should be
confined to patients with radiolucent gall-
stones in „functioning" gallbladders —
those which opacify well during oral chole-
cystography and contract in response to a
fatty meal. Stones which „float“, forming'
a distinct layer or raft in the mixture of
bile and cholecystographic contrast mate-
rial on erect X-ray films, are almost in-
variably cholesterol-rich stones. Patients
with gallstones of this type are most likely
to benefit from CDCA therapy.
II Radiolucent non-cholesterol gallstones
Some 15—20% of radiolucent stones are
not cholesterol-rich (arbitrarily defined as
> 75% cholesterol by weight) in type;
they are, therefore, unsuitable for medical
treatment. This is particularly true of
small stones with an irregular contour
which „sink“ during cholecystography
when the films are taken with the patient
erect. However, there is no certain way of
detecting such patients based on X-rays
alone nor even, in our experience, when
the X-rays are combined with an analysis
of bile-rich duodenal fluid. Although in
theory, up to l/5th of patients with radio-
lucent stones may have non-cholesterol
calculi, in practice fortunately this
happens only rarely. Out of some 165 gall-
stone patients treated medically in our
own unit, we have seen only 4 who failed
to respond to treatment, came to chole-
cystectomy and were found to have radio-
lucent „pigment" stones.
III Radio-opaque stones
Although we have known for 5—6 years
that radio-opaque gallstones do not respond
to CDCA treatment, many patients are
still referred to our clinic for cheno-
therapy with partially calcified stones.
Even a faint rim of calcification or the
presence of a calcified nucleus in the
centre of the stone seems to prevent com-
plete gallstone dissolution. It is NOT ade-
quate to accept verbal or even written
reports about the radiological appearance
of the gallstones. The doctor treating the
patient should review the X-rays person-
ally. Many X-rays are technically unsatis-
factory because of an inadequate number
of films, poor quality X-rays or because
overlying bowel gas has obscured the gall-
stones. If in doubt, or if the X-rays have
not been taken within 3 months of starting
treatment, they should be repeated.
Equally, if the patient has had an attack
of severe biliary colic or cholecystitis
since the last X-ray was taken, the oral
cholecystogram should be repeated lest the