Pemphigoid (Herpes) Gestationis (PG)

The aims of this leaflet

This leaflet is designed to tell you more about Pemphigoid Gestationis. It tells you what the condition is, what causes it, what can be done about it and where to find out more about it.  

What is Pemphigoid Gestationis?

Pemphigoid Gestationis is a rare skin blistering disorder that occurs in pregnant women. It usually starts in pregnancy but can also come back in women when they take oral contraceptive therapy orhave their periods for some time after the pregnancy.
It usually starts with an itchy rash that develops into blisters. It is commonest during mid to late pregnancy (the 2nd  and 3rd  trimesters).  

What causes Pemphigoid Gestationis?

Pemphigoid Gestationis is an auto-immune blistering disease which means that the woman’s   immune system reacts against her own skin causing skin blistering.
Female hormones (particularly oestrogen) are thought to aggravate the reaction and this may be why it starts during the stage in pregnancy when oestrogen levels rise. Pemphigoid Gestationis may come back in further pregnancies and also may also come back in some women who take oral contraceptive therapy or with their periods following pregnancy, but later on there is usually no problem.  

Does Pemphigoid Gestationis run in families?

No, but there is a link with other auto-immune diseases (which may run in families) such as thyroid disease and pernicious anaemia. 

What are the symptoms of Pemphigoid Gestationis?

Itching is common and often starts around the umbilicus (belly button) during mid to late pregnancy (13 to 40 weeks of the pregnancy). Itching may be followed by a rash with large red inflamed areas of skin and then later blisters may develop. 

What does Pemphigoid Gestationis look like?

There is often a rash with wheals (like hives, nettle rash or urticaria) and large raised red patches commonly occurring on the trunk, back, buttocks and limbs. The face, scalp, mouth and genital area are usually not involved.  Large tense blisters then appear on the red patches within 1-2 weeks, and are also seen on palms and soles. The blisters usually contain clear fluid or occasionally blood-stained fluid. There is usually no scarring when the blisters heal.  

How will Pemphigoid Gestationis be diagnosed?

Diagnosis requires a skin sample (biopsy) and/or a blood test for special laboratory tests (immunofluorescence). Usually the appearance and behaviour of the rash is very typical, but in early disease without blisters the rash can look like other skin diseases.  

Can Pemphigoid Gestationis be cured?

No but it can be suppressed with treatment. The symptoms often improve towards the end of pregnancy but many women will experience a flare of the rash around the time of delivery. In most cases symptoms resolve days or weeks after giving birth, but in some women the disease can remain active for months or years and may require continued treatment. Restarting periods, use of oral contraceptive therapy can all cause flare-ups of the disease for some time after delivery as can further pregnancies.  

How can Pemphigoid Gestationis be treated?

The primary aim of treatment is to relieve itching, prevent blister formation and treat any secondary infection. It is also important during pregnancy to use treatments that are as safe as possible for both mother and baby.
The use of emollients, (moisturising) creams and ointments can help with the inflammation and discomfort of the skin as can bathing or showering in emollient and soap substitutes. 
Steroid creams or the greasier steroid ointments are necessary to relieve symptoms. The steroid cream or ointment should only be applied to affected areas of skin and a mild (for example hydrocortisone) or moderate steroid cream should be used. The amount should be as small as possible, and ideally only 1-2 small (15-30g) tubes should be used for a few days and intermittently. However, if the condition is severe then application of a stronger steroid cream or ointment to the skin in larger quantities is still better than steroids given by mouth. 
Mild to moderate strength steroid creams or ointments appear to be safe during pregnancy but stronger steroid creams and ointments may cause problems with the growth of the unborn baby, so that they may be born small especially if the mother is using large amounts (more than 50 gm, 1/2 large tube per month or over 200-300gm, 2-3- large tubes, in the whole pregnancy) of steroid creams or ointments.
Treatment for more severe disease (with blistering) is usually with high doses of steroid tablets to get the disease under control rapidly. This needs careful monitoring and should involve the obstetricians, to look at both the health of the mother and baby. The dose of steroid tablets may need to be increased at the end of pregnancy to prevent the disease flaring after delivery.
 
Antihistamines may be helpful to treat the itch. The following are considered safe in pregnancy:
non-sedating: Loratadine, Cetirizine, and sedating (drowsy making): Clemastine, Dimethindene, Chlorpheniramine.
 
Blisters may be burst (with a sterile needle) to offer relief from discomfort and dressings can be applied to weepy or raw areas of skin. 
Other drugs may be used in more severe cases or in women who experience severe disease following delivery.  

Will the baby be affected?

Occasionally the baby will develop a blistering rash following delivery due the mother’s antibodies crossing the placenta. This only occurs in 5-10% of babies and the rash is usually only temporary lasting up to 6 weeks until the antibodies are cleared. Usually mild treatment only is required such as emollients, mild steroid creams or ointments and dressings.
The baby is at increased risk of premature delivery and may be relatively small for dates. With this in mind it is important that the obstetrician and dermatologist monitor the pregnancy closely with careful observation of the baby’s size and growth, particularly if the mother is taking steroid tablets or if the mother is using large amounts (more than 200 gm, 2 large tubes) of steroid creams or ointments.
It has been shown recently that this reduction in foetal growth is not due to treatment with steroid tablets but due to disease severity. Therefore early treatment is essential in such cases.  

Is normal delivery possible?

Yes and Caesarean section is not recommended for this condition unless there are other indications. Blistering can develop at the site of the scar and may require treatment. Blistering of the vulva and vagina can occur but only in a minority of cases.  

Are the treatments safe for the baby and mother?

Mild to moderate strength steroid creams or ointments appear to be safe during pregnancy and can be used, but stronger steroid creams and ointments may cause problems with the growth of the unborn baby, so that they may be born small.
 
With steroid tablets there is always an increased risk of developing diabetes (raised sugar levels) and hypertension (raised blood pressure). Careful observation of blood pressure and urine checks are therefore essential for the mother at antenatal clinic, while ultrasound scans can look for any
changes in the baby’s growth. Women who have been taking steroid treatment for a prolonged period may not be able to stop the drugs immediately and should see a doctor for advice about the best way to reduce treatment.  

Can women with Pemphigoid Gestationis still breastfeed?

Yes. Even while taking steroid tablets women should still be encouraged to breastfeed as only negligible amounts of steroid get into breast milk. There is some evidence that breastfeeding may make the rash disappear more quickly.  

Is any special monitoring required?

Yes, regular review at an antenatal clinic is even more important if the mother is taking steroid tablets orally and blood tests, urine tests, blood pressure checks with ultrasound scans are all extremely important to monitor the mother and baby’s wellbeing.  

Where can I get more information about Pemphigoid Gestationis?

Link to on-line support group
http://health.groups.yahoo.com/group/PemGest/
Web links to detailed leaflets
www.dermnetnz.org/immune/pemphigoid-gestationis.html
www.emedicine.com/derm/topic178.htm  
 
This leaflet has been prepared by the EADV task force “skin disease in pregnancy”, it does not necessarily reflect the official opinion of the EADV
 
Updated July 13