Book of Medical Disorders in Pregnancy - Tintash

owel, but conjugated bilirubin is not.
On reaching the ingestible bilirubin is
acted upon by the bacterial flora and is
enzymatically reduced to a series of
colorless urobilin-nogen. About 50 per
cent of the urobilin-nogen is reabsorbed
into the portal circulation and thus
returned to the liver. Most of this
compound is removed from the blood
and re excreted into bile. If the liver is
normal and the rate of urobilino-gen
return is not too rapid. The tiny amount
of absorbed urobilinogen which is not re
excreted amounts to less than 4 mgm per
day this passes into the systemic blood
stream and is then removed in the urine.
The excretion of bilirubin is dependent
on mechanisms which limit biliary and
intestinal reabsorption. Uro-bilinogen is
formed predominantly in the lower
intestinal tract, while absorption of
bilirubin metabolites occurs maximally
in an area which is proximal to the
terminal ileum. The urobilinogen in the
lower intestine is excreted in the stools
and amounts to about 300 mgm daily.
Oxidation of urobilinogen to urobilin
gives colour to the stool.
Jaundice: Jaundice is a clinical state
where there is an increase in the level of
bilirubin in the blood. This can occur in
four different ways. Firstly, there might
be an increased load of the pigment on
the liver cell. Second, there might be a
disturbance in the process by which
bilirubin diffuses into the cells from the
sinusoids and is actively transported to
the microsome for conjugation.
Thirdly, there may be defects in the
actual con-jugation process and finally,
there may be difficulty in the passage of
bile via the biliary tract, to the intestine.
Multiple disturbances can coexist in
anyone patient.
Liver function in pregnancy:
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In normal pregnancy there is very little
significant change in the liver function.
Both the blood flows as well as the
parenchymal structure of the liver are
not affected. However some of the
biochemical tests show slight alteration.
Liver biopsy does not show any pathological
change.
Jaundice in Pregnancy:
Incidence - Jaundice occurs in 1: 1500
pregnancies in Europe. The exact incidence
in Pakistan is not known. There
were 3 cases of Jaundice at Lahore General
Hospital in 1000 pregnancies.
Causes - In a number of studies viral
hepatitis has been reported to be responsible
in 40 per cent cases, re-current intrahepatic
cholestatic jaundice in about
20 per cent, bile duct obst-ruction in
another 5 per cent and in the remaining
35 per cent cases there may be other
causes.
Different types: Recurrent Intrahepatic
Cholestatic Ja-undice of Pregnancy' -
This is an obst-ructtive type of jaundice
which occurs in the later half of
pregnancy, usually in the last trimester.
The exact cause of this complication is
not known but an abnormal cholestatic
reaction to steroids produced in
pregnancy has been implicated. Similar
changes occur in patients who have been
using synthetic sex steroids for contra
captive purposes.
Diagnosis – Liver Biopsy shows dilated
bile can-aliculi with stasis of bile.
Both conjugated bilirubin and alkaline
phos-phatase are increased. The