Papulosqamous Diseases

Question 1

Acute or chronic inflammatory dermatosis involving skin and/or mucous membranes

HLA-associated

Age of onset – 30-60 years old

Occurs in females > males

Answer 1

Lichen Planus

Question 2

What are some causes of lichen planus?

Answer 2

idiopathic (most cases) - Cell-mediated immunity (lymphocytes) plays a major role

Drugs

Viral (Hep C)

Metals (gold, mercury)

Question 3

“pruritic polygonal purple papules” – the four P’s

Distributed bilaterally and symmetrically

Common sites include flexor surfaces, genital skin, and mucous membranes (Virtually never seen on palms, soles, or face)

Most causes are idiopathic but evidence supports a cell-mediated immune response that damages basal keratinocytes

Histologic evaluation via punch biopsy

Answer 3

Lichen Planus

Question 4

What is the pathogenesis of lichen planus?

Answer 4

Dense infiltrate of lymphocytes occupies the papillary dermis and superficial dermis with vacuolization of the lower dermis - Lymphocytes attack the keratinocytes

CD4 🡪 CD8 shift

Colloid bodies – dense eosinophilic globules

Melanocytes may be destroyed accidentally

Question 5

Minute whitish streaks due to neutrophil deposits

Answer 5

Wickham’s striae

Question 6

Patients who have oral lichen planus are at an increased risk for what?

Answer 6

Increased risk of oral SCC

Question 7

Itchy eruption with numerous small papules - May form larger plaques

Angulated borders with flat tops

Violaceous hue

Wickham’s striae

Oral, erosive lesions with cancer patient

Answer 7

Lichen Planus

Question 8

What are some treatment options for lichen planus?

Answer 8

Topical or Systemic glucocorticoids

Cyclosporine or Tacrolimus solution

PUVA

Systemic Retinoids

Antihistamine (itching)

Question 9

Acute exanthematous eruption with a distinctive morphology and
often self-limited course

Age of onset

10-43 years

Common in spring and fall

Answer 9

Pityriasis Rosea

Question 10

What is the etiology of Pityriasis Rosea?

Answer 10

HHV 6 or 7 reactivation

Question 11

A single herald patch precedes the exanthematous phase which
develops over a period of 1-2 weeks - Salmon-red, fine collarette scale at periphery

Exanthem:
Dull pink or tawny

Oval, scattered with characteristic distribution with the long axes of the oval lesions following the lines of cleave in a “Christmas tree” pattern

Answer 11

Pityriasis Rosea

Question 12

What are some differential diagnoses to consider when evaluating for potential Pityriasis Rosea?

Answer 12

Syphilis - Consider RPR as truncal rash mimics secondary syphilis

Tinea corporis

Tinea versicolor

Viral exanthems

Drug eruptions

Question 13

What is the treatment for Pityriasis Rosea?

Answer 13

Symptomatic only!

Antihistamines/antipruritic lotions

Topical glucocorticoids

May be improved by UVB phototherapy or natural sunlight exposure if
treatment is begin in the first week of eruption

Question 14

Chronic disorder with polygenic predisposition and triggering
environmental factors (Can also be spontaneous)

Classic form: Sharply demarcated and erythematous and surmounted by silvery scales

T-cell driven autoreactive immune response

Familial/hereditary

Answer 14

Psoriasis

Question 15

What is the pathogenesis of Psoriasis?

Answer 15

Keratinocyte cycle alteration (shortened keratinocyte cell cycle and doubling of proliferative of cell population) causes thickening

Neutrophils migration plus parakeratotic cells = silvery scales

Pronounced dilation, tortuosity and increased permeability of capillaries

Question 16

In patients with Psoriasis, what percentage also have Psoriatic arthritis?

Answer 16

Psoriatic arthritis in 10-25% of cases

Question 17

What are some trigger factors for Psoriasis?

Answer 17

Physical injury (Koebner’s phenomenon)
Infections
Environmental factors
Stress
Drugs
ETOH

Question 18

What are the two major types of Psoriasis?

Answer 18

Eruptive: Inflammatory; Multiple, small lesions

Chronic: Stable plaque, Does not go away

Question 19

Which type of Psoriasis is precipitated by streptococcal pharyngitis?

Answer 19

Guttate

Question 20

What is the most common site for Psoriasis?

Answer 20

Extensor surfaces

Question 21

Sharp margins

Bright erythema

Non-confluent

Whitish or silvery scales (fish-like)

Lesions may occur at any site - Extensor surfaces most common

Affects nail bed and matrix - Pitting of nailbed and oil spots

Answer 21

Psoriasis

Question 22

What are some treatment options for Psoriasis?

Answer 22

Topical Fluorinated glucocorticoids

Hydrocolloid dressing

Vitamin D (watch hypercalcemia) +/- antibiotics

UV radiation

Coal tar

Methotrexate or Cyclosporine

TNF Inhbitors