Pregnancy dermatoses Melissa

Question 1

Pemphigoid gestationis -when

Answer 1

Onset from 4/52 gestation to 1/52 post partum

• Commonest 21-28/52
• Subsequent pregnancy onset usually earlier
• May become quiescent later in pregnancy then flare post-partum
• Usually lasts weeks  months after birth, Occasionally lasts years

Question 2

Pemphigoid gestationis: May be seen with…

Answer 2

May also be seen with hydatiform moles and choriocarcinoma

Fathers more often HLA-DR2

Question 3

Pemphigoid gestationis: antigen

Answer 3

BP 180 (BPAG2; collagen XVII) > 230
Predominantly IgG1

Question 4

Pemphigoid gestationis

Answer 4

PROGNOSIS
Often flares at delivery
3-10% Infant can have blistering in the 1st 2/52  emollients only
May be weeks, months to years before resolution
Exacerbation may be seen with menstruation
OCP  flare  contraindicated whilst disease active
Likely to recur in subsequent pregnancy
More or less severe 10% of subsequent pregnancies are normal

Question 5

Pemphigoid gestationis- exam and spares what

Answer 5

• Urticated papules, plaques and target lesions
• Blisters & vesicles arise within
• Eruption often begins around the umbilicus
• Spreads to abdomen and thighs
• Extremities, palms and soles can be affected
• Spares mucosa, face, palms, soles
• Can spread to neonate

Question 6

Pemphigoid gestationis associations and risks

Answer 6

Associations
Autoimmune diseases such as 
-	Graves'
-	Vitiligo
-	Alopecia areata
Association with premature delivery and risk of low birth weight, neonatal pemphoid gestationis

Question 7

Pemphigoid gestationis

Answer 7

TREATMENT
General
Education about current and subsequent pregnancies
Consider admission

Topical
Mild cases  may get by with potent topical steroids alone

Systemic
Prednisolone (40mg/d) 0.5mg/kg – taper as soon as blister formation suppressed.
Use once blistering occurs
May need to increase post-partum for flares
Does pass into milk
Antihistamines - Will pass into breast milk  drowsiness

2nd / 3rd Line Rx
IVIG, Plasmapheresis, AZA (as an adjunct with steroids)

Question 8

Pemphigoid gestationis - dapsone could be used

Answer 8

Dapsone contraindicated

Not effective and causes haemolytic disease of the newborn

Question 9

Pemphigoid gestationis - histo

Answer 9

Histopathology
Early : Epidermal and papillary dermal oedema
Occasional foci of eosinophilic spongiosis
Later: subepidermal blisters filled with eo’s
C3 linear deposition along BMZ
IgG1 autoantibodies directed against a transmembrane hemidesmosomal protein (BP180; collagen XVII)

DIF:IgG (30%) + C3 (100%) in linear pattern
Also seen in BP, HG, EBA and bullous SLE
IgG1 > IgG4 in PG vice versa in BP 1 > 4
May see only linear C3 in BP & HG
Differentiating between these two is impossible on DIF or histo
Salt split skin IgG epidermal fragment

IIF +ve in 10%
HG factor  amplified IIF procedure
Amplified and detected by the complement binding properties of the antibody  50% +ve

Question 10

Polymorphic eruption of pregnancy=Pruritic Urticarial Papules and Plaques of Pregnancy: how common

Answer 10

1:130-1:300

Question 11

Polymorphic eruption of pregnancy=Pruritic Urticarial Papules and Plaques of Pregnancy . who and when

Answer 11

during later portion of 3rd trimester or immediately post partum.
Primiparous women usually. Higher risk: multiples, male fetus, C section.

Question 12

Polymorphic eruption of pregnancy=Pruritic Urticarial Papules and Plaques of Pregnancy - recurs?

Answer 12

Does not recur unless multiple gestation, no maternal or fetal risks Unusual to recur with OCP

Question 13

Polymorphic eruption of pregnancy=Pruritic Urticarial Papules and Plaques of Prengnancy

clinical features

Answer 13

Urticarial papules and plaques +/- vesicles usually in striae. Usually periumbilical sparing. Spares face, palms, soles
Duration – 6/52
Spontaneous remission within a few days of delivery.
Development of polymorphous features (vesicles, erythema, target and eczematous lesions) with disease progression

Question 14

Polymorphic eruption of pregnancy=Pruritic Urticarial Papules and Plaques of Pregnancy - aeitology

Answer 14

Aeitology:
abdominal skin may lead to damage of connective tissue and elicitation of allergic type reaction. Cross reactivity to collagen

Question 15

Polymorphic eruption of pregnancy=Pruritic Urticarial Papules and Plaques of Pregnancy DDx

Answer 15

DDx: urticarial pemphioid gestationis, Pemphigoid gestationis, atopic eruption of pregnancy. Also drug eruption, viral exanthema, pityriasis rosea, eczematous dermatitis, scabies.

Question 16

Polymorphic eruption of pregnancy=Pruritic Urticarial Papules and Plaques of Pregnancy
Tx

Answer 16

Topical CS, pred if bad

Reassurance

Question 17

Polymorphic eruption of pregnancy=Pruritic Urticarial Papules and Plaques of Pregnancy
Histo

Answer 17

• Non specific
• Spongiosis , acanthosis with hyperkeratosis and parakeratosis
• Sometimes exocytosis of eosinophilis

Question 18

Which drugs to use in pregnancy
pred
antihistamines
topicals

Answer 18

Antihistamines
o Chlorpheniramine : 1st trimester
o 2nd/3rd: loratadine
Systemic
o Pred: largely inactivated in placenta mother:fetus 10:1
o 1st trimester weeks 8-11: possible increased risk of cleft lip/palate esp if high doses are prescribed and for >10 days; longer duration of therapy ok if doses are

Question 19

physiological changes in pregnancy

Answer 19

-	Hyperpigmentation
o	Melasma 70%, areola/linear nigra (90%)
-	Hair
o	Hirsutism
o	Telogen effluvium – may last up to 15 months
o	Post partum androgenic alopecia
-	striae
o	up to 90%
-	vascular
o	spider angiomas, pyogenic granulomas

Question 20

Pustular psoriasis of pregnancy = impetigo herpetiformis

Answer 20

May be concerned as a type of pustular psoriasis BUT often has absence of +ve family hx, abrupt resolution of sx at delivery, a tendancy to recur at subsequent pregnancies. Factors known to trigger pustular psoriasis eg infection, drugs, rebound from steroids are often absent

Question 21

Pustular psoriasis of pregnancy = impetigo herpetiformis

Answer 21

Usual onset 3rd trimester

Question 22

Pustular psoriasis of pregnancy = impetigo herpetiformis Maternal and foetal risk

Answer 22

Foetal risk: placental insufficiency may lead to stillbirth or neonatal death
Maternal risk: sepsis or hypocalcaemia (rare)

Question 23

Pustular psoriasis of pregnancy = impetigo herpetiformis Ix

Answer 23

Investigations
FBC: leucocytosis, neutrophilia, anaemia
ESR: elevated 
Albumin: low 
Ca, Phosphate, Vit D: may be low 
Culture: negative
Swab: negative

Question 24

Pustular psoriasis of pregnancy = impetigo herpetiformis features

Answer 24

Erythematous patches with subcorneal pustules at their margins.

Begins in flexures, generalises demonstrate centrifugal spread.

Often associated constitutional symptoms eg fever, chills, malaise, diarrhoea, nausea & arthralgias. Tetany, delirium and convulsions occur if hypocalcaemia is severe.

Question 25

Pustular psoriasis of pregnancy = impetigo herpetiformis features
Tx

Answer 25

Resolution post delivery
Monitor fluids and electrolytes, cardiac & renal function
Fetal monitoring for decrease in HR (sign of hypoxaemia)
Topical treatments: wet dressings and topicals
Systemic CS
Cyclosporin 5-10mg/kg
nbUVB + steroids
Infliximab

Question 26

Autoimmune progesterone dermatitis

Answer 26

• can appear during pregnanc or post partum
• cyclic flares of dermatitis which correspond to luteal phase
• tx involves inhibiting ovulation via estrogen containing preps

Question 27

Atopic eruption of pregnancy

Answer 27

In pregnancy there is a switch to Th2 cytokine production (IL4 and IL10) less (IL12 – TH1) which worsens imbalance in atopic patients

Question 28

Atopic eruption of pregnancy

where and who already has eczema and when

Answer 28

Eczematous or papular individuals with a person/familial atopic background and/or eleveated serum IgE.
75% before 3rd trimester

20% exacerbation of pre existing atopic dermatitis
2/3 lesions in atopic sites
1/3 papular eruption on trunk and extremities: prurigo or small erythematous papules, xerosis
20% flare of existing eczema
80% no hx of atopic eruption or after a long remission.

Question 29

Intrahepatic cholestasis of pregnancy

TX

Answer 29

Treatment
Close foetal monitoring, may require early induction of labour
Reduce bile acid levels
Ursodeoxycholic acid : safe, only SE is mild diarrhoea 15mg/kg daily or 1g daily until delivery. Reduces maternal sx and fetal risk.
Enhances bile acid excretion.
Cholestyramine: May help 70% in mild-mod. Can take several days for effect. But may precipitate Vit K & a coagulopathy.
Bland emollients, antihistamines + UVB
Monitor coags
Remits at 2-4 weeks post delivery. May recur with OCP

Question 30

Intrahepatic cholestasis of pregnancy

Presentation

Answer 30

Intense itching, worse at night
Starts palms and soles, then generalised
Jaundice only 10%-20% of patients
Pruritis persists until delivery
Protacted course is unusual – would need to look for other liver disease esp primary biliary cirrhosis
Fatigue, nausea, vomiting or anorexia

Question 31

Intrahepatic cholestasis of pregnancy

pathogenesis

Answer 31

Reduced excretion of bile acids
Crossing placenta can lead to acute fetal anoxia due to abnormal uterine contractility and vasoconstriction of chorionic veins as well as impaired fetal cardiomyocyte function
One predisposing factor is mutations in genes that encode bile transporter proteins. When transporters capacity to secrete substrates is exceeded eg in setting of high levels of sex hormones in pregnancy, signs and symptoms of cholestasis can develop.

Question 32

When and where

cholestatic eruption of pregnancy

Answer 32

Onset 3rd trimester (highest placental hormone levels)
10% 1st, 25% 2nd trimester

Recurs in 45-70% of subsequent pregnancies. Higher in multiple pregnancies. Can recur with OCP

Most common in south America, positive family hx in up to 50% - may be related to higher hormone levels
Higher risk hep C, selenium deficiency, increased intestinal permeability

Question 33

Intrahepatic cholestasis of pregnancy

Answer 33

Diagnosis serum bile acid >11micromol/L (normal in non pregnant 0-6) – often >40
During pregnancy ALP usually increase due to placenta anyway and GGT levels are lower than in non pregnancy state.
Transaminases are usually elevated but may be normal in 30%
Hepatic USS is normal but may reveal gallstones in jaundiced patients

Question 34

Intrahepatic cholestasis of pregnancy

Answer 34

Risk to mum: steatorrhea, vit K deficiency (increased risk of post partum haemorrhage), later risk of cholelithiasis or gallbladder disease
Highest risk to fetus: Increased risk of prematurity 20-60%, intrapartum fetal distress 20-30% and stillbirths 1-2% (increased placental anoxia, meconium stained amniotic fluid)