BOF: 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.
Last Updated: 1/05/06
