Pruritus Flashcards
What are the causes of pruritus in pregnancy
Obstetric cholestasis
Polymorphic eruption of pregnancy
Atopic eruption of pregnancy
Pemphigoid gestatoinis
OR pre-existing dermatological conditions e.g. xerosis, eczema, infections, systemic disease etc.
What is obstetric cholestasis / intrahepatic cholestasis of pregnancy (ICP) and what is the cause
Pruritis and raised bile acids with no alternative diagnosis
What is the epidemiology of obstetric cholestasis / intrahepatic cholestasis of pregnancy (ICP)
Most common cause of itch presenting without a rash in pregnancy
Affects 1 in 100 in the UK, with 1/3 having a family Hx
What is the aetiology of obstetric cholestasis / intrahepatic cholestasis of pregnancy (ICP)
Thought to be due to deposition of bile salts in the skin with elevated levels of lysophosphatidic acid (LPA)
Autosomal dominant sex-linked inheritance
(Oestrogen has a cholestatic effect on the liver and other reproductive hormones affect the function of bile acid transport within hepatocytes, the COCP may precipitate a similar syndrome.)
What are the symptoms of obstetric cholestasis / intrahepatic cholestasis of pregnancy (ICP)
From 28w gestation (80% after 30w)*
Itch/pruritis: Starts/is noticeable on the soles and palms then spreads to the trunk and limbs, Worse at night
Jaundice (10%)
Anorexia and malaise
Abdominal pain
Dark urine
Pale stools or steatorrhoea
(no rash)
*Hep C (HCV) positive women present earlier
What investigations should be done for obstetric cholestasis / intrahepatic cholestasis of pregnancy (ICP)
Same-day referral to a local maternity unit
Diagnosis of exclusion (PET, AFLP, viral hepatitis, autoimmune hepatitis, drug induced hepatic impairment)
Bedside: urine dip, BP (PET)
Bloods
- LFTs and bile acids: ↑bile acids ↑transaminases ↑ALP/bilirubin ↑ gamma-GT
- hep A/B/C serology: -ve
- EBV and CMV serology: -ve
- Anti-smooth muscle (anti-Sm) and anti-mitochondrial antibodies: normal
- FBC
Other: liver USS, CTG
What is the management for obstetric cholestasis / intrahepatic cholestasis of pregnancy (ICP)
Same day referral to maternity unit
Antenatal
1. Symptomatic relief
- Emollient e.g. menthol 0.5%
- Sedating antihistamines e.g. chlorphenamine at night
2. Treatment
- Ursodeoxycholic acids + vit K supplements
- Rifampicin second line
3. Self-care
- Sit in front of a fan, soak in cool bath, apply ice baths to affected areas, cooling substances (aloe), cool, loose, cotton clothing
4. Monitoring: weekly LFTs, 2x doppler and CTG, consultant-led care
Intrapartum (risk of stillbirth)
BA>100: deliver at 35-36 weeks
BA 40-100: Deliver at 38-39 weeks
BA<40: Deliver at 40+ weeks
Postpartum
Should resolve from 48h - 4-6w
Postnatal LFTs from 2 weeks onwards until resolved, contact obstetrics if not after 8w
Advise against COCP
What are the complications of obstetric cholestasis / intrahepatic cholestasis of pregnancy (ICP)
Stillbirth
Premature delivery
Meconium aspiration or meconium stained liquor
Foetal distress
Vitamin K deficiency
Bacterial infection of excoriations caused by scratching
What are the features of polymorphic eruption of pregnancy (risk factors + symptoms)
Third trimester, usually first pregnancy and in women with excessive weight gain or multiple pregnancy
Pruritic urticarial papules that coalesce into plaques
1. Abdomen, first on the striae with umbilical sparing
2. May remain localised, spreading to the buttocks and proximal thighs, or become widespread
3. May later develop into widespread non-urticated erythema
Lasts 4-6 weeks but does not pose serious risk to baby
What is the management for polymorphic eruption of pregnancy
Emollients
Consider topical corticosteroids
Offer sedating antihistamine e.g. chlorphenamine or promethazine
+ self-care
What are the features of Pemphigoid gestationis
Rare autoimmune disorder that often occurs in the third trimester
1. Intense itch
2. erythematous urticarial papules and plaques on the abdomen, then spread to cover the body
3. Tense blisters/bullous rash
Flares up at delivery with subsequent spontaneous regression over the following weeks to months
Associated with an increased risk of preterm delivery and low infant birth weight
Neonates born to women with pemphigoid gestationis may have a mild, transient skin rash (10%)
What is the management for Pemphigoid gestationis
Topical corticosteroids
Antihistamines
Additional antenatal surveillance due to risk of preterm birth and reduced foetal growth
+ self-care
What self-care advice is given to women with pruritus in pregnancy
Bathing:
- Spend <20 minutes in the bath
- Bathe less frequently (2-3 weekly)
- Use cool or lukewarm water
- Avoid bubble baths, soap, and perfumed products
- Use mild, alcohol-free cleansers or an emollient as a soap substitute
- Avoid drying the skin and pat dry instead
Cool showers can provide short-term relief, but they should not do this too often
Nails should be kept short, try to rub instead of scratch
Indoor environment should be kept cool, especially the bedroom
Wear cotton or silk, avoid wool or synthetics
Avoid spicy foods, alcohol, and caffeine which may cause vasodilation to worsen the itch
What are the physiological changes to the skin in pregnancy
Linea nigra
Pre-existing conditions (e.g. acne can worsen during pregnancy) - Acne flares in 3rd trimester – oral or topical erythromycin, retinoids contraindicated
Increased pigmentation (face, areola, abdo midline) common
Spider naevi affecting face, arms, upper torso
Broad pink linear striae – striae gravidarum common over lower abdo and thighs
Hand and nipple eczema common post-partum
Psoriasis – topical steroids, methotrexate contraindicated
What are the symptoms of pruritis folliculitis and what is the management
2nd or 3rd trimester, resolve a week after delivery
Acne (considered a type of hormone-induced acne)
Pruritic follicular eruption with papules and pustules affecting trunk can involve limbs
M: topical steroids
