Pilosebaceous Unit, Apocrine, and Eccrine Glands

Question 1

Four segments of a pilosebaceous unit

Answer 1

keratinized follicular infundibulum, hair, sebaceous gland, sebaceous duct, connects gland to infundibulum

Question 2

Common microorganisms in sebaceous glands

Answer 2

malazzezia (tinea versicolor), S. epidermis, and propionibacterium (acne pathogenesis).

Question 3

Holocrine secretion

Answer 3

from sebaceous glands, cells disintegrating and releasing a light, viscous fluid.

Question 4

Components of sebum

Answer 4

Free FA’s, wax, and sterol esters, triglycerides, and squalene, produced at a rate of 1 mg per 10 cm sq. every three hours.

Question 5

Higher sebum production associated with:

Answer 5

seborrheic dermatitis

Question 6

Lower sebum production associated with:

Answer 6

xerosis, atopy

Question 7

Pathogenesis of acne vulgaris

Answer 7

DHEAS and testosterone production post-puberty increase sebum production and contribute to development of acne.

Question 8

How acne develops

Answer 8

1. abnormal keratinization, with increased proliferation and retention of corneocytes in acroinfundibulum form microcomodones
2. microcomodone expands, sebaceous lobule undergoes regression, accumulation of sebum and keratinocytes create raised comodone
3. compaction continues, comodones rupture and lead to inflammation. Pustules associated with neutrophiles, mixed influx in inflammatory papules, nodules, and cysts.

Question 9

Clinical features of acne vulgaris

Answer 9

Closed comodones (“whiteheads”) approximately 1 mm skin-colored pustules w/ no follicular openings. Open comodones (“blackheads”) are dome-shaped papules w/ dilated follicular outlets. Melanin deposition gives blackhead color.

Question 10

Common site of acne in women, indicating hormonal influence

Answer 10

chin and jawline.

Question 11

Clinical expression of acne fulminans

Answer 11

Most severe cystic acne in young men 13-16 years old. Characterized by abrupt eruption of nodular and suppurative acne in association w/ systemic manifestations, including fever, malaise, myalgias, and hepatosplenomegaly. Painful, oozing, friable plaques with hemorrhagic crust. Significant scarring.

Question 12

Describe acne conglobata

Answer 12

severe eruptive acne w/o systemic manifestations. Part of follicular occlusion tetrad.

Question 13

Describe acne mechanica

Answer 13

result of mechanical or frictional obstruction of pilosebaceous unit by helmet, chin strap, suspenders, or collars: follows linear or geometric patterns

Question 14

Describe acne excoriee

Answer 14

Result of excoriation or manipulation, common in pts with anxiety disorder, OCD, or personality disorders.

Question 15

Describe drug-induced acne

Answer 15

Commonly from anabolic steroids, corticosteroids, lithium, phenytoin, isoniazid, iodines, or bromides. An abrupt, monomorphous eruption of inflammatory papules in contrast to heterogenous morphology in lesions of acne vulgaris.

Question 16

Describe neonatal acne

Answer 16

In 20% of healthy newborns, appear around 2 weeks and gradually resolve by 3 months of age. Small, inflammatory papules typically arising on cheek and nasal bridge.

Question 17

Describe infantile acne

Answer 17

Neonatal acne that persists beyond 3 months. Suggests mild hormonal imbalance. Deep cystic lesions and pustules occasionally. From DHEA from their immature adrenal glands! Should resolve by around 12 months.

Question 18

Indications for use, use, and side effects of topical retinoids

Answer 18

Commonly: tretinoin or adapalene. Normalizes follicular keratinization, expulsion of existing comedones, and prevention of new lesions. Instruct pt to use on entire face.

Question 19

Indications for use of topical anti-inflammatory agents

Answer 19

Include: benzoyl peroxide (BPO) and topical antibiotics (clindamycin, sulfur/sulfacetamide) for their anti-inflammatory and anti-bacterial properties. Apply directly to lesion.

Question 20

Antibiotics as acne treatment and their indications for use

Answer 20

Reduces inflammation of papules, pustules, and nodules. Common ones: tetracycline (main one), doxycycline, minocycline, and trimethoprim-sulfamethoxazole. Best used for a short period of time.

Question 21

Side effects of tetracycline used for acne treatment

Answer 21

nausea/vomiting, pseudotumor cerebri, photosensitivity (tetracycl, doxycycl), blue-gray pigment deposition (minocycl), lupus-like symptoms (minocycl), dizziness

Question 22

Another option for acne treatment in women, especially acne related to hormone fluctuations

Answer 22

oral contraceptives or spironolactone (inhibits testosterone receptor)

Question 23

Acne lesions grade and treatment recommendations

Answer 23

1: comodones (topical retinoids, BPO)
2: superficial inflammatory (topical retinoids, BPO, topical antibiotics)
3: papular/ pustular (combined topical and systemic therapy)
4: nodulcystic (systemic isotretinoin)

Question 24

Treatment recommendation for severe or nodulocystic acne

Answer 24

Isotretinoin to shrink sebaceous glands and open follicular ostia, thereby reducing acne severity. Teratogenic, so careful with women. Monitor for ocular, cutaneous, psychological, and musculoskeletal side effects. Systemic side effects of hepatic toxicity or hyperlipidemia.

Question 25

Women on isotretinoin must sign the iPLEDGE and are educated on:

Answer 25

teratogenicity, depression and mood disturbances, nausea/vomiting, pseudotumor cerebri, tinnitus, myalgias and artralgias, hyperlipidemia, and hepatotoxicity.

Question 26

Pathogenesis of rosacea

Answer 26

Multi-factorial. Pt hx of blushing easily and inflammatory acneiform papules on cheeks and nose. Triggers are food or medicine that induce vasodilation, thermal stimuli, and UV light. Some association b/w helicobacter pylori and demodex folliculorum with rosacea reported in some individuals.

Question 27

Common triggers of rosacea

Answer 27

environmental stimuli (UV light, wind, cold, humidity), emotional stress, heat, alcohol consumption, spicy foods.

Question 28

Clinical features of rosacea

Answer 28

Primary diagnostics: flushing, non-transient erythema, telangiectasis, papules and pustules (mostly on central face), absences of comodones. Secondary: burning or stinging, xerosis on central face, edema, ocular manifestation including dry eyes, foreign body sensation, burning or stinging, rhinophyma

Question 29

Variants of Rosacea

Answer 29

Periorifical dermatitis: small erythemous papules in perioral or periocular areas. HALLMARK: sparing of vermillion border. Exacerbated by topical steroids. Pyoderma faciale: acute eruption of inflamed papules and pustules in centrofacial region. Condition can occur in patients who begin with mild rosacea Steroid rosacea: topical or systemic steroids exacerbate rosacea, controlled w/ systemic antibiotic or topical calcineurin inhibitor. Discont steroid use.

Question 30

Treatment of Rosacea

Answer 30

Topical antibiotics (metronidozole, sulfur, BPO), systemic tx (oral antibiotics), surgical tx (laser and lights). Retinoids of limited use. Laser for dilated vessels.

Question 31

Location and function of apocrine glands

Answer 31

Axilla and anogenital region. Function unknown, like olfactory communication.

Question 32

Pathogenesis and clinical presentation of hidradenitis suppurativa

Answer 32

Occlusion of apocrine sweat glands, leading to chronic condition with recurrent boils and draining sinus tracts with subsequent scarring. Begins at puberty, more common in women.

Question 33

What is the follicular occlusion triad? (AKA acne inversa)

Answer 33

acne conglobata, hidradenitis suppurativa, and dissecting cellulitis of the scalp (perifollicular pustules, nodules, abscesses, and sinuses that evolve into scarring alopecia). Pt sometimes presents with pilonidal cyst, creating follicular tetrad. Pathology thought to be hyperkeratinization.

Question 34

Tx for hidradentis suppurativa

Answer 34

Topical: antibiotics, absorbent powder, antiseptic soap, aluminum chloride Systemic: prednisone, oral retinoids, oral antibiotics Surgical: intralesional steroids, injection, incision and drainage, laser

Question 35

Areas of highest concentration of eccrine ducts

Answer 35

Axilla, palms, soles.

Question 36

Excretory function of eccrine glands used for delivery of what medication?

Answer 36

oral ketoconazole, used to treat widespread fungal infection.

Question 37

Tx of hyperhidrosis

Answer 37

aluminum chloride, in anti-perspirants, can be prescribed at higher doses. Apply for two days in a row to dry skin and then only as needed. Too much and there is skin irritation.

Question 38

Use of oral anti-cholingergics (glycopyrrolate) for tx of hyperhidrosis

Answer 38

Reduces stim of sweat glands as part of SNS. Slowly increase dose or side effects of orthostatic hypoTN, blurred vision, dry mouth and urinary retention.

Question 39

Use of botulinum toxin to tx hyperhidrosis

Answer 39

prevents ACh release to prevent stim of sweat glands. Well-tolerated in axilla, painful in palms and soles.

Question 40

sugical sympathectomy uses for hyperhidrosis

Answer 40

For palmar hyperhidrosis only. Cut sympathetics in the neck, but potential side effect of compensatory hyperhidrosis has no cure.