Skin Flashcards
What are some physiological skin changes in pregnancy? (7)
- Increased pigmentation
- Melasma: light brown facial pigmentation, develops in approx 70% women, often in second half of pregnancy
- Spider naevi: face, upper trunk, arms
- Palmar erythema: present in up to 70% women by the third trimester
- Hypertrichosis and hirsutism: in response to high oestrogen and progesterone hair cycle stays in anogen phase promoting growth; 3-6 months postpartum changes to telogen phase and hair starts to fall out
- Striae gravidarum
- Pruritis (without rash or cholestasis)
What is a possible complication of psoriasis in pregnancy?
Impetigo herpetiformis (a rare, severe form of pustular psoriasis)
Urticated erythema, beginning in the flexures and particularly the groins, is associated with sterile pustules, which may become widespread and affect mucosa.
Condition associated with severe systemic upset - fever, neutrophilia, hypocalcaemia.
Rx: systemic corticosteroids, regular fetal surveillance
Obstetric implications:
- Increased risk of LBW
- Often recurs in subsequent pregnancies
NB. Most psoriasis improves in pregnancy
Of women with eczema, what % will suffer an exacerbation in pregnancy?
20%
What are the management options for Psoriasis in pregnancy?
1st - Emollients, topical corticosteroids, topical calcipotrial (a vit D analogue)
2nd - Narrowband UVB or broadband UVB
3rd - Ciclosporin and anti-TNF alpha biologics
NOT MTX: antimetabolite, teratogenic
Also contraindicated in pregnancy: hydroxyurea, acitretin
What is erythema nodosum?
Inflammation of the subcutaneous fat
Typically presenting as tender erythematous nodules over the anterior lower legs
May occur in pregnancy without any known cause
TB and Sarcoidosis should be excluded with a CXR
The woman should be asked about symptoms of streptococcal infection and IBD, as well as recent meds (esp. sulfonamides)
What is erythema multiforme?
Acute self-limiting condition predominantly affecting the peripheries
Symmetrical eruption
Erythematous Papules that evolve into concentric rings of varying colour with central pallor
May complicate pregnancy without obvious cause
Common causes: drugs, viral infections (particularly HSV)
What is the most common pregnancy-specific dermatosis?
PEP / PUPPP
Polymorphic eruption of pregnancy
Incidence 1:200, i.e. 0.5%
When does PEP normally present?
Third trimester
Mean gestational age at onset is 34/40
Resolves postpartum
What is the distribution of the rash in PEP?
Abdomen (with umbilical sparing), along the striae
Spreading to the thighs, buttocks, under the breasts and upper arms
How would you describe the rash seen in PEP?
Pruritic
Urticaria Papules and plaques,
Erythema
And rarely, vesicles or target lesions
What is the pathogenesis of pemphigoid gestationis?
Autoimmune (possibly related to exposure to fetal antigens)
Binding of circulating complement-fixing IgG antibodies to a protein (bullous pemphigoid antigen 2) in the hemidesmosomes of the basement membrane zone of the skin, triggers an immune response leading to the formation of sub-epidermal vesicles.
Associated with other autoimmune conditions e.g. Grave’s disease, vitiligo, T1DM, RA
How is pemphigoid gestationis diagnosed?
1) Skin biopsy and direct immunofluoresence
- shows complement (C3) deposition at the basement membrane zone.
- (negative in PEP)
2) Serum indirect immuonfloresecnece show antibodies in blood serum (30-100% cases)
What are the fetal risks in pemphigoid gestationis?
LBW
PTB
Suggestion of but less evidence for stillbirth
The neonate may be affected with a similar bullous eruption
This occurs in 10% cases and is mild and transient
What is the treatment for Pemphigoid gestationis?
- Topical potent or ultrapotent corticosteroids (e.g. 0.05% clobetasol propionate)
- MOST require Systemic steroids (e.g.g 40mg prednisolone od)
- Topical or systemic ciclsporin or tacrolimuis
- Sedating antihistamine
How would you describe the rash seen in Pemphigoid gestationis?
Intensely pruritis
Urticated erythematous papules and plaques
Target lesions
Annular wheals
After delay of approx 2/52: vesicles, large tense bullae form
What is the distribution of the rash seen in pemphigoid gestationis?
Abdomen (umbilicus AFFECTED), lesions begin in periumbilical region
Spreading to limbs, palms and soles
What are the risk factors for PEP?
First pregnancy Multiple gestation Excessive gestational weight gain White skin Male fetus
What is the pathophysiology of PEP?
Stretching of the abdominal skin
Elicits an immune response due to connective tissue damage
What are the four dermatoses of pregnancy?
- Obstetric cholestasis
- Pemphigoid gestationalis
- PUPP
- Atopic eruption of pregnancy
Pemphigoid gestationis
Clinical features?
Rare (1 in 50,000)
onset at any gestation up to 1 week postpartum
Starts periumbilical
Itchy macular papular rash
Spreads to trunk, buttocks, arms
Excludes face scalp palms soles and mucous membranes
Target lesions and plaques
Forms vesicles and large tense bullae after 2 weeks
Pemphigoid gestationis
Histology
subepidermal vesicle formation (subepidermal blister)
immunopathological by deposition of complement 3 (C3) along the basement membrane zone (dermal perivascular inflammatory infiltrate)
Pemphigoid gestationis
Complications?
Secondary bacterial infection, Preterm delivery SGA Stillbirth neonatal bullous eruption (10%),
Pemphigoid gestationis
Management?
Potent Topical Steroids (Mild Disease)
Systemic Steroids (Severe)
Antihistamine (oral)
Third line: Azathioprine, ciclosporin, IV IG, plasmapheresis.
Pemphigoid gestationis
Advice?
Usually resolves postpartum, but if onset postpartum higher risk of progression to bullies pemphigoid with prolonged recovery several months
Obstetric risks: LBW, PTB, stillbirth, bullous eruption of neonate (mild)
Usually recurs in subsequent pregnancies
May be earlier and more severe in future pregnancies,
Associated with other organ-specific autoimmune diseases esp Graves
Can recur with combined hormonal contraceptives
PUPP clinical features?
Common (1 in 200)
Assoc with multiple gestation and increased maternal wgt gain
Usually in primps
Usually in third trimester
Begins over the abdomen in striae, with sparing of the periumbilical
Spreads to breasts, upper thighs and arms.
Excluded face palms soles and mucous membranes
PUPP histological features?
Non-specific
Negative Immunofluorescence studies
Management PUPP?
Emolient Menthol creams Hydrocortisone 1% cream Sedating antihistamines Rarely potent/ultrapotent topical steroids
Recurrence of PUPP in future pregnancies?
Unusual for recurrence in future pregnancies
What is the incidence of atopic eruption of pregnancy?
1 in 300
What are the features of atopic eruption of pregnancy?
Majority (75%) onset BEFORE third trimester
20% cases have pre-existing hx eczema
Presents with eczematous papule and plaques in limb flexures, face, neck etc
Also red/brown pruritic papules over limbs and trunk
Self resolves post partum
No adverse obstetric outcomes
May recur in future pregnancy
Why does acne typically get worse in pregnancy?
Higher androgen levels, particularly in third trimester
Increased sebum secretion by sebaceous glands
What happens to eczema and psoriasis in pregnancy?
Why?
Grossly speaking eczema deteriorates and psoriasis improves.
Due to move from Th1 to Th2 predominant state - meaning a reduction in cell mediated immunity and increase in autoimmune conditions.
However, either can improve or deteriorate in pregnancy.
