Lecture 11

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Questions and Answers

What triggers mast cell degranulation in autoimmune cases?

Exercise

Pressure on the skin

Cold temperatures

IgG antibodies binding to IgE receptors (correct)

Which treatment is most effective for chronic urticaria (CU) according to the provided treatment options?

Three-month courses of cyclosporine (correct)

Only non-sedating antihistamines

Chronic use of systemic steroids

A single high-potency antihistamine

What is the recommended approach for antihistamine treatment in chronic urticaria?

Combining a sedating high-potency antihistamine with a non-sedating antihistamine (correct)

Using one sedating antihistamine only

Using only over-the-counter antihistamines

Using two non-sedating antihistamines only

What percentage of patients will experience no improvement after a three-month course of cyclosporine for CU?

33% Signup and view all the answers

What common physical cause is linked to hives after a hot shower?

Increased temperature Signup and view all the answers

Which condition is the most common dermatosis specific to pregnancy?

Pruritic Urticarial Papules and Plaques of Pregnancy Signup and view all the answers

In which trimester does PUPPP typically occur?

Late third trimester Signup and view all the answers

What is a common trigger for the development of PUPPP in pregnant women?

Stretching of the skin Signup and view all the answers

What area of the body is typically spared during the rash associated with PUPPP?

The umbilicus Signup and view all the answers

What is the typical treatment for severe cases of PG?

Systemic corticosteroids Signup and view all the answers

How does Pemphigoid Gestationis typically present initially?

As red papules around the umbilicus Signup and view all the answers

What is the typical prognosis for PUPPP after delivery?

Symptoms resolve within 1-2 weeks Signup and view all the answers

Which type of birth outcome is Pemphigoid Gestationis associated with?

Increased risk of premature delivery Signup and view all the answers

What is the most common symptom of irritant hand dermatitis on exposure to water?

Burning or stinging Signup and view all the answers

Which layer of the skin is primarily responsible for protecting against irritants?

Stratum corneum Signup and view all the answers

What is the recommended method to decrease exposure to water in patients with irritant hand dermatitis?

Wearing rubber gloves over cotton liners Signup and view all the answers

What characterizes acute urticaria?

Blanched papules or plaques Signup and view all the answers

In irritant hand dermatitis, what commonly happens when soap is used frequently?

Removes the oil layer more than the skin can recreate Signup and view all the answers

What is the primary underlying cause of acute urticaria?

Activation of mast cells by antigens Signup and view all the answers

Which treatment is discouraged for chronic use in irritant hand dermatitis due to its potential to impair healing?

Topical steroids Signup and view all the answers

Which statement accurately describes Lichen Planus (LP)?

LP is commonly associated with mild itchiness and purple papules. Signup and view all the answers

Which symptom is commonly associated with hives in acute urticaria?

Itching Signup and view all the answers

What is the most common area affected by cutaneous Lichen Planus?

The flexor wrists Signup and view all the answers

Which characteristic is associated with oral Lichen Planus?

Red patches with white lines in a net-like pattern Signup and view all the answers

What triggers the immune response in Lichen Planus?

Virus or controversial factors Signup and view all the answers

Which treatment is primarily used for cutaneous Lichen Planus?

High potency topical steroids Signup and view all the answers

Granuloma Annulare (GA) typically presents with which feature?

Raised yellow-to-orange rings Signup and view all the answers

What is the common demographic affected by Granuloma Annulare?

Young adult to middle-aged females Signup and view all the answers

What biopsy finding is associated with Granuloma Annulare?

Mucin and granulomas Signup and view all the answers

Which age group is most commonly affected by prurigo nodularis?

Middle-aged to elderly individuals Signup and view all the answers

What is the characteristic appearance of prurigo nodules?

Well-circumscribed, hyperpigmented, and hyperkeratotic nodules Signup and view all the answers

How does a prurigo nodule develop?

It starts as an itchy area before developing into a nodule after scratching Signup and view all the answers

What is a key distinction regarding the diagnosis of prurigo nodularis?

It is a secondary diagnosis resulting from primary skin conditions Signup and view all the answers

What type of medications can be beneficial in treating prurigo nodularis?

Tricyclic antidepressants and neuropathic agents like gabapentin Signup and view all the answers

Which area of the body do prurigo nodules typically spare?

Face Signup and view all the answers

What is a common risk factor for developing irritant hand dermatitis (IHD)?

Frequent handwashing or wearing rubber gloves Signup and view all the answers

Why is prurigo nodularis considered similar to lichen simplex chronicus (LSC)?

Both involve hypertrophy of cutaneous nerve twigs Signup and view all the answers

What triggers mast cell activation in response to an antigen?

Cross-linking of two IgE molecules bound to an antigen Signup and view all the answers

Which of the following is classified as a fast-acting mediator?

Histamine Signup and view all the answers

What is the main mediator responsible for the itch associated with urticaria?

Histamine Signup and view all the answers

Which of the following is the first-line treatment for acute urticaria?

Antihistamines Signup and view all the answers

What characterizes chronic urticaria (CU)?

Hives occur almost daily for at least 6 consecutive weeks Signup and view all the answers

What distinguishes slow-acting mediators from fast-acting mediators in mast cells?

Slow-acting mediators are produced only after mast cell activation Signup and view all the answers

What is a common misconception regarding antihistamines and urticaria treatment?

Antihistamines completely resolve hives and itching Signup and view all the answers

Which of the following drugs is ranked highest for effectiveness in treating acute urticaria?

Doxepin Signup and view all the answers

Study Notes

Miscellaneous Dermatoses in Pregnancy

Pruritic Urticarial Papules and Plaques of Pregnancy (PUPPP)/Polymorphic Eruption of Pregnancy (PМЕР): Most common pregnancy dermatosis (0.5-1% of first pregnancies). Rare after first pregnancy. Incidence increases with maternal weight gain, especially common in twin pregnancies. Begins in abdominal striae, often spreads but spares the umbilicus. Characterized by erythematous, edematous papules and plaques, sometimes vesicles. Highly pruritic. Resolves within 1-2 weeks postpartum. Topical steroids and oral antihistamines often effective.
Pemphigoid Gestationis (PG): Less common than PUPPP. Typically occurs late in pregnancy. Lesions start as red papules/plaques that evolve into tense blisters. Often widespread. Recurs with subsequent pregnancies. Autoantibodies directed against bullous pemphigoid antigens. Associated with increased risk of premature delivery and low birth weight. Requires systemic corticosteroids for severe cases. Oral antihistamines and topical steroids may be used for milder cases but are often not effective.

Lichen Planus (LP)

Characteristics: Uncommon skin condition (affecting less than 1% of the population), typically in middle-aged individuals, but can occur at any age, without racial predilection. Classic presentation includes pruritic, purple, planar, polygonal papules with Wickham's striae (fine white lines). Common locations include flexor wrists, forearms, shins, and sacral regions. Can also affect oral/genital mucosa.
Mechanism: An autoimmune disease; lymphocytes (primarily CD8+ T-cells) attack the epidermis. The triggers are unknown but possibly a virus.
Treatment: High-potency topical steroids for mild-moderate disease; systemic immunosuppressants for severe, unresponsive cases.

Granuloma Annulare (GA)

Characteristics: Relatively common dermatosis, primarily affecting young to middle-aged females. Characterized by yellow-to-orange, raised rings with slightly raised, smooth borders. Common in the backs of hands. Can affect large areas in some cases. Asymptomatic; spontaneous resolution is typical.
Mechanism: Pathogenesis unknown, but biopsies show granulomas and mucin.
Treatment: Often resolves spontaneously; topical steroids may be ineffective. Cryotherapy with liquid nitrogen can be effective in persistent cases.

Other Conditions

Pretibial Myxedema (PM): Associated with Graves' disease (thyroid disorder) but occurs in less than 5% of Graves' patients. Characterized by shiny, indurated nodules/plaques on the shins—variable skin colour (skin-colored, red, brown). Accumulation of mucin in the dermis. Usually not itchy.
Lichen Simplex Chronicus (LSC): Common in patients with atopic dermatitis, hyperpigmented thickened plaques, accentuated skin lines, and possible fissures/bleeding. Develops from chronic scratching and rubbing leading to an “itch-scratch cycle."
Prurigo Nodularis: Hyperpigmented, hyperkeratotic nodules frequently itchy. Affects primarily middle-aged females, but can occur at any age. Often associated with an “itch-scratch cycle”. Can be treated with topical or intralesional steroids in mild-moderate cases. More severe cases may require antihistamines or systemic therapies such as immunosuppressants.
Irritant Hand Dermatitis (IHD): Common in people who frequently wash their hands or wear rubber gloves. Characterized by erythema, scaling, and burning/stinging in involved areas (dorsal hands, palms, interdigital spaces). Can be caused by exposure to strong irritants or excessive hand washing.
Acute Urticaria (Hives): Most common in children and young adults. Characterized by blanched papules or plaques (hives) with surrounding erythema. Itchy and can affect any location. Often related to mediator release from mast cells responding to antigens. Relieved with antihistamines. More severe cases might need systemic steroids.
Chronic Urticaria (CU): Hives that occur continuously or daily for at least 6 weeks. Usually more numerous and widespread than acute urticaria. Often idiopathic or autoimmune; Can be associated with physical triggers (pressure, temperature). Often treated with multiple antihistamines along with other treatments based on underlying causes.

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Description

Explore the various dermatoses encountered during pregnancy, focusing on conditions like Pruritic Urticarial Papules and Pemphigoid Gestationis. Understand their characteristics, incidence, management, and implications for maternal and fetal health. This quiz will enhance your knowledge about pregnancy-related skin issues.