OBGYN Dermatology Flashcards
DDX for common pruritic conditions in pregnancy WITH PRIMARY LESIONS
With primary lesions: pemphigoid gestationis, polymorphic eruption of pregnancy, atopic eruption of pregnancy
Ddx for common pruritic conditions in pregnancy WITHOUT a primary lesions
Without a primary lesion: intrahepatic cholestasis.
When in pregnancy does this condition erupt?
Key features: rare, pruritis, vesiculobullous eruption that develops during late pregnancy or immediate postpartum.
Diagnosing Pemphigoid Gestationis: ___ __ deposition along the basement membrane zone (BMZ) by direct __. __ autoantibodies are directed against a transmembrane __ protein
Diagnosing Pemphigoid Gestationis: Linear C3 deposition along the basement membrane zone (BMZ) by direct IF. IgG1 autoantibodies are directed against a transmembrane hemidesmosomal protein
Pemphigoid Gestationis: causes?
Increased risk of prematurity and SGA neonates; the risk correlates with disease severity
Commonly results in subsequent pregnancies
Thought to be triggered by paternal antigen in the placenta
Abrupt onset of cutaneous lesions on the trunk, in particular the abdomen and often within or immediately adjacent to the umbilicus
Spares the mucous membranes
When does atopic eruption of pregnancy often occur in gestation?
80% of atopic skin changes for the first time during pregnancy. Happen earlier on.
Atopic Eruption of Pregnancy
Key Features; eczematous and or papular skin lesions in a patient with an atopic diathesis in whom other specific dermatoses have been excluded
Onset; 20% of women experience an exacerbation of pre-existing atopic dermatitis, 80% develop atopic skin changes for the first time during pregnancy.
Distribution: ⅔ eczematous lesions often involving “atopic sites” such as the face, neck and flexural aspects of the extremities, ⅓ develop papular eruption on the trunk and extremities.
MOST COMMON pruritic disorder during pregnancy
Generally appears EARLIER than other pregnancy related dermatoses.
Nonspecific histology; negative direct IF, elevated serum igE levels in up to 70% of patients
No maternal or fetal risks; commonly recurs in subsequent pregnancies
Would not get immunofluorescence (can differentiate between pemphigoid gestationis)
Pathogenesis: preventing fetal rejection– normal pregnancy is characterized by a LACK of strong maternal cell-mediated immune function and reduced Th1 cytokine production, as well as a dominant humoral immune response with increased Th2 cytokine production.
This natrual switch towards a dominant Th2 response, which worsens the imbalance already present in most atopic patients, is thought to favor the development of AEP
When in pregnancy does this usually erupt?
Polymorphic eruption of pregnancy. usually happens in third trimester- immediately post partum.
Pathogenesis; rapid, late stretching of abdominal skin may lead to damage of connective tissue and elicitation of an allergic-type reaction, resulting in the initial appearance of the eruption within striae.
Intrahepatic Cholestasis of Pregnancy
Definition:pruritus without primary skin lesions with an onset during the third/last trimester.
Sudden onset of intense, generalized pruritus
Extensor surfaces of the extremities, buttocks and abdomen are usually most severely affected.
Secondary changes correlated with disease duration and vary from subtle excoriations to severe prurigo nodularis.
Elevated total serum bile acid levels are diagnostic; histology is nonspecific and IF is negative
Increased risk of prematurity, intrapartum fetal distress, and stillbirths
Recurs in 45-75% of subsequent pregnancies.
Pathogenesis: key element is reduced excretion of bile acids, which provokes severe pruritis in the mother. Toxic bile acid crossing the placenta may also may have deleterious effects on the fetus
Abnormal uterine contractility and vasoconstriction of chorionic veins, impaired fetal cardiomyocyte function, all this can lead to acute fetal anoxia
- List a differential diagnosis for common non-infectious vulvar lesions that cause pruritis.
Lichen sclerosis
Lichen simplex chronicus
Psoriasis
treatment? key features?
inverse Psoriasis
Key features: lack of scale, involves skin folds, symmetry bilaterally on either side of the fold, may be pruritic or asymptomatic
May be difficult to differentiate from LSC
Look for family history of psoriasis or for other signs of psoriasis in scalp, nails, umbilicus, external ear and extensor surfaces.
Treatment: sedating antihistamine, mid to high potency topical corticosteroid ointments, calcineurin inhibitors for patients requiring topical steroids more than 3x weekly.
Also the same treatment for LSC and LS treatment.
Lichen Sclerosis
Key features: __, ivory-white flat papules and plaques with epidermal __ and __ plugging. Most commonly affects female or male genitalia, less often extragenital skin.
Key features: sclerotic, ivory-white flat papules and plaques with epidermal atrophy and follicular plugging. Most commonly affects female or male genitalia, less often extragenital skin.
Bartholin Cyst
Cyst Mechanism: a duct may become obstructed secondary to inflammation or trauma. Bartholin gland duct cysts are often asymptomatic. If they cause discomfort, it is typically less severe than with an abscess.
Key Features: erythematous vulvar mass, dyspareunia, or pain with walking or sitting
Abscesses usually spontaneously rupture after 3-4 days
Abscesses are commonly polymicrobial, although neisseria gonorrhoeae is a common isolate.
Complications: squamous cell carcinoma is a rare complication of Bartholin gland pathology.
N. gonorrhoeae and C. trachomatis may cause abscess and adenitis and swabs should be taken for culture.
treatment for abscess?
Treatments for Abscess:
Ruptures: sitz bath every 8-12 hours
Unruptured, sitz bath every 8-12 hours, incision and drainage with subsequent placement of a WORD catheter for 4-6 weeks or until it falls out
Antibiotics not indicated with adequate drainage
Excision should be reserved for recalcitrant cases and not performed at times of active infection
Treatments for Cyst:
Notreatment for asymptomatic lesions
Symptomatic cysts may be marsupialized
Antibiotics for Abscess infection:
Consider covering for N. gonorrhea: ceftriaxone or ciprofloxacin
Consider covering for C. trachomatis: doxycycline or azithromycin 1 g by mouth as a single dose.
Antibiotics for Abscess infection:
Consider covering for N. gonorrhea: __ or __
Consider covering for C. trachomatis: __ or __ 1 g by mouth as a single dose.
Antibiotics for Abscess infection:
Consider covering for N. gonorrhea: ceftriaxone or ciprofloxacin
Consider covering for C. trachomatis: doxycycline or azithromycin 1 g by mouth as a single dose.
