Pigmentation/Cornification Disorders

Question 1

ichthyosis

Answer 1

• “Fish” refers to fish like scales
• **most common cornification disorder**
• deficiency in filaggrin = impaired formation of cornified keratinocytes
  
  • increased epidermal water loss
  • increased likelihood of inflammatory response when exposed to irritants and allergens
• Mild-moderate scaling on the extensor extremities
• tx:
  
  • emollients (petrolatum, mineral oil = especially after a bath/shower to lock in moisture)
  • keratolytic agents
    
    • retinoids

Question 2

Keratosis Pilaris

Answer 2

• cornification disorder
• keratotic follicular papules
  
  • tend to affect upper arms, thighs, and lateral cheeks
• tx:
  
  • hydrate skin with gentle cleansers and moisturizers
  • keratolytic agents
    
    • salicyclic acid, or retinoids consistently for months

Question 3

Vitiligo presentation and cause

Answer 3

• family hx of thryoid disease, DM, and vitiligo have increased risk of developing of vitiligo
• Multifactorial cause:
  
  • 1. autoimmune
  • 2. self-destruction of melanocytes
  • 3. neurogenic: nerve ending that secrete a neurochemical mediatory that is cytotoxic to melanocytes (segmental vitiligao)
  • 4. oxidative stress, melanocyte separate from basement membrane
• Generalized vitiligo (most common) vs localized vitiligo
  
  • localized: dermatomal pattern, rarely spread beyond dermatome
    
    • more common in children

Question 4

vitiligo workup and tx

Answer 4

• workup:
  
  • woodlamp examination: obvious depigmentation
  • dermoscopy may be useful
  • if unclear diagnosis: biopsy
  • perform full body skin exam and ROS to include endocrine and autoimmune disease
  • consider TSH with reflex T4
• Tx:
  
  • rapidly progressing? low dose oral prednisone for 2 weeks, break for 4-6 weeks then repeat if necessary
  • narrow band UVB therapy 2-3 times/week for 6 mo
  • topical steroids
  • topical calcineruin inhibitors (tacrolimus, pimecrolimus)
  • excimer laser
  • can lighten rest of skin if >40% affected (monobenzone)
  • make up

Question 5

Melasma

Answer 5

• symmetric, hyperpigmented patches with irregular borders as a results of increased epidermal or dermal melanin
• favors the face then the upper-mid chest then the extensor forearms
• skin phototypes III-IV in women mostly
  
  • pathogenesis: hyperfunctional melanocytes reacting to hormones or sun exposure
• Pt ed: avoid sun exposure/tanning beds
  
  • daily sunblock use
  • sun protections
  • discontinue oral contraceptive pills (OCP)
• tx:
  
  • hydroquinone 4-8% + retinoid + CS for 2-3 months then 2-3x/week for 1-2 months then stop
  • azelaic acid 15-20%
  • consider adding antioxidant
  • Laser/Microneedling

Question 6

Answer 6

Ichthyosis vulgaris

• Filaggrin deficiency = impaired formation of cornified keratinocytes
  
  • increases your loss of epidermal water
  • much more likely to have inflammatory rxn when exposed to irritants or allergens
• diagnosis:
  
  • clinical diagnosis
• tx:
  
  • Emollients or keratolytic agents

Question 7

Answer 7

Keratosis pilaris

• keratotic follicular papules may have som emild erythema
• thigsh, lateral cheeks, upper arms
• diagnosis:
  
  • clinical
• tx:
  
  • thick moisturizers (keep skin hydrated)
  • keratolytic agents: (must be used for months)
    
    • salicylic acid
    • retinoids
    • adapalene

Question 8

Answer 8

Vitiligo

• **increased prevalnce with family hx of thyroid disease, DM, and vitiligo**
• segmental/localized: more common in children
• Generalized: most common form
• diagnosis:
  
  • Woods lamp: obvious depigmentation
  • dermoscopy
  • consider biopsy from edge of vitiligo if unclear diagnosis
  • consider TSH with reflex T4
• ​Tx:
  
  • rapidly progressing? prednisone for 2 weeks, then rest 4-6weeks, repeat if necessary
  • narrow band UVB therapy for 6 months
  • topical steroids
  • topical calcineurin inhibitors (tacrolimus, pimecrolimus)
  • Monobenzone (skin lightener) for pts with vitiligo > 40% BSA

Question 9

Answer 9

Melasma

• hyperfunctional melanocytes
• stimulated by sun exposure and hormones
• family hx
• **most common in women in skin phototypes III-IV**
• diagnosis:
  
  • clinical
• tx:
  
  • sun protection
  • camouflage make up
  • discontinue OCPs if possible
  • (hydroquinone 4-8% (bleaches skin) +retinoid + corticosteroid (fluocinolone acetonide)
    
    • 2-3months then 2-3x/week for 1-2 months then stop

Question 10

Answer 10

Pityriasis Alba

• **commonly associated with children/adolescents, especially if they have atopic dermatitis**
• hypopigmented macules and patches with subtle fine scales
• located on face> shoulders/arms
• diagnosis:
  
  • clinical
• tx:
  
  • treat the atopic dermatitis
  • sunscreen
  • emollients
  • low grade topical steroids can help

Question 11

Answer 11

Acanthosis nigricans

• common marker for insulin resistance
• velvety, hyperpigmented plaques that are poorly define
• most common in neck, axillae, and other body folds
• diagnosis:
  
  • clinical
  • may want to check A1C
• tx:
  
  • tx underlying condition
  • treat skin with topical keratolytics (retinoid)