BOF: 3.49
A 27-year-old Asian female attends the antenatal clinic
complaining of intense itching of her skin. This is generalised but the palms
and soles of her feet are affected to a greater degree. The pruritus is
increased at night. She is in her 34th week of gestation and has
had no complications and is otherwise well. On direct questioning she reveals
that her mother had similar problems during pregnancy and had been told that
this was a normal occurrence.
On examination she looked well and there were no
abnormalities clinically.
Investigations showed elevated transaminases but all
other investigations were normal.
The registrar in obstetrics who sees this patient rings
you up for advice regarding this patient. Your advice would be:
a)
Treat with ursodexoycholic acid and plan to deliver the baby between
36-38 weeks
b)
Admit the patient for MRI scanning to localise the site of biliary
obstruction
c)
Admit the patient and arrange an ERCP
d)
Deliver the baby by caesarean section immediately to prevent stillbirth
e)
Admit the patient and have her seen by the infectious disease team as
the patient probably has viral hepatitis
Answer: a)
This patient probably has obstetric cholestasis (OC).
This is a condition in which there is pure cholestasis with no necrosis of
cells and no inflammation. Oestrogens and progestogens are thought to play the
primary part in this condition. It is most common when levels of these
hormones are high that is in late pregnancy and multiple pregnancies. The
condition resolves after delivery.
The condition usually presents at 30-36 weeks of
gestation (may start in the first trimester). The presenting feature is
pruritus, which is generalised but tends to affect the palm and soles of the
feet in particular and is worse at night. A positive family history may be
obtained in 30%.
There are no abnormalities on physical examination and
the only abnormality usually found on investigation is elevated transaminases.
In a patient presenting with pruritus in pregnancy, the
finding of elevated transaminases with no other abnormality (clinically or on
laboratory testing) is diagnostic of obstetric cholestasis.
Serum bile acid levels are a more specific marker of
obstetric cholestasis.
The foetus is at greater risk in these patients, the
complications being prematurity, foetal distress, meconium staining,
stillbirth and perinatal death.
It is best to deliver the baby between 36-38 weeks as the
risk of stillbirth increases after 36 weeks of gestation.
Ursodexoycholic acid reduces bile acid levels and may
ameliorate pruritus. It has not been shown to improve foetal outcome
Revision Tip
Revise obstetric cholestasis
KEYS to SUCCESS in Medicine page 288-289
