78: Acne Vulgaris Flashcards
What are the common clinical features of acne vulgaris?
- Comedones
- Papules
- Pustules
- Nodules
These lesions typically appear on the face, chest, and back.
What is the prevalence of acne vulgaris among adolescents aged 12-25 years?
The prevalence of acne vulgaris is approximately 85% among individuals aged 12 to 25 years.
What factors are considered in the history of a patient with acne vulgaris?
- Gradual onset of lesions around puberty
- Abrupt onset may indicate an underlying etiology
- Hyperandrogenism in females with severe acne
- Drug-induced acne from various medications
What are the types of lesions associated with acne vulgaris?
- Noninflammatory comedones (open or closed)
- Inflammatory lesions (red papules, pustules, or nodules)
Closed comedones are referred to as whiteheads, while open comedones are known as blackheads.
What is the significance of family history in patients with acne vulgaris?
Family history of acne has been reported in 62.9% to 78% of patients, with those having a family history tending to be male and experiencing earlier onset, truncal involvement, and scarring.
What are the four key elements of pathogenesis in acne vulgaris?
- Follicular epidermal hyperproliferation
- Sebum production
- Presence and activity of Propionibacterium acnes
- Inflammation and immune response
How does the prevalence of acne vulgaris vary by age and gender?
- Prevalence: 85% among ages 12-25 years.
- Adolescents: Higher prevalence in males.
- Adults: Higher prevalence in females.
What factors should be considered in a female patient with severe acne?
- Hyperandrogenism: Consider if acne is severe, sudden in onset, or associated with hirsutism or irregular menstrual periods.
- Family history: May indicate a genetic predisposition to more severe forms of acne.
What types of scars can result from acne lesions?
Acne lesions can lead to different types of scars, including:
- Atrophic scars: ice pick, boxcar, rolling
- Hypertrophic scars
What is the initial clinical lesion that develops in acne?
All clinical lesions in acne begin with the microcomedo, which develops into comedones, inflammatory lesions, and scarring.
What is the significance of abandoning the term ‘nodulocystic’ in the context of severe acne?
The term ‘nodulocystic’ should be abandoned because true cysts are rarely found in acne. Instead, the term ‘severe nodular acne’ is more appropriate to describe severe cases of inflammatory acne.
What are the major psychosocial impacts of acne on young people?
Acne is a major cause of psychosocial and psychological impairment, leading to increased rates of depression, anxiety, and psychosocial stress.
What are the key elements involved in the etiology and pathogenesis of acne?
- Follicular epidermal hyperproliferation
- Sebum production
- Propionibacterium acnes
- Inflammation and immune response
What complications can arise from acne lesions after resolution?
Complications that can arise from acne lesions after resolution include:
- Transient macular erythema
- Postinflammatory hyperpigmentation, especially in dark skin, which may persist for months
- Acne scars, which can be atrophic or hypertrophic.
Describe the process that leads to the formation of a microcomedo in acne pathogenesis.
The formation of a microcomedo in acne pathogenesis involves the following steps:
1. Follicular epidermal hyperproliferation
2. Obstruction of the follicular ostium
3. Accumulation of keratin, sebum, and bacteria
4. Dilation of the upper hair follicle
5. Formation of a microcomedo
What are the characteristics of a microcomedo in the pathogenesis of acne?
- Hyperkeratotic infundibulum
- Cohesive corneocytes
- Sebum secretion
- Dilation of follicular ostium
What occurs during the formation of an inflammatory papule or pustule in acne?
- Rupture of follicular wall
- Further expansion of follicular unit
- Proliferation of Propionibacterium acnes
- Perifollicular inflammation
What is the significance of a nodule in the context of acne pathogenesis?
- Rupture of follicular wall
- Marked perifollicular inflammation
- Scarring
What defines a comedone in the acne pathogenesis process?
- Accumulation of shed corneocytes
- Sebum
- Dilation of follicular ostium
What are the key pathological changes that occur during the formation of a microcomedo in acne vulgaris?
The formation of a microcomedo involves:
1. Hyperkeratinization of the infundibulum.
2. Accumulation of shed corneocytes.
3. Formation of comedones.
4. Sebum secretion leading to dilation of the follicular ostium.
Describe the inflammatory process that leads to the formation of a nodule in acne vulgaris.
The formation of a nodule involves:
1. Rupture of the follicular wall.
2. Marked perifollicular inflammation.
3. Development of papules or pustules.
4. Potential scarring as a result of the inflammatory response.
What role does Propionibacterium acnes play in the pathogenesis of inflammatory acne lesions?
Propionibacterium acnes contributes to the pathogenesis of inflammatory acne lesions by:
- Proliferating within the follicular unit, leading to inflammation.
- Triggering an immune response, which exacerbates the inflammatory process.
What factors contribute to keratinocyte hyperproliferation in acne?
Factors include:
- Androgen stimulation
- Decreased linoleic acid
- Increased IL-1 activity
- Effects of P. acnes
- Dihydrotestosterone
How does P. acnes contribute to inflammation in acne?
P. acnes induces inflammation through various mechanisms:
- Contains a carbohydrate antigen that stimulates antibody development.
- Elicits a delayed-type hypersensitivity response.
- Stimulates host innate responses via secretion of proinflammatory cytokines and chemokines.