Skin Disorders Flashcards
Eczema and other variant symptoms
Inflammatory Disorder
Spongiotic Dermatitus
Erythema, scale, pruritic (itchy)
Types:
Atopic: occurs in children until adolescence on extensor surfaces. Associated with Asthma and allergic rhintis (runny nose). In older children, on flexural surfaces. The more you scratch the more it rashes.
Contact Dermatitis: caused by irritant or allergic contact.
-Type 4 Hypersensitivity: Antibody against cell surface antigens
Histologically: Spongiosis Epidermal, lymphotic exocytosis, perivascular lymphotytes, histiocytes, and eosinophils in blood vessels. Solar Elastosis also present. Acanthosis. Parakeratosis
Psoriasis symptoms and types
Inflammatory Disorder
Erythematous plaques with silvery scale. Pitting on nails, acanthosis (thicking) of epidermis, neutrophils within epidermis, prominent rete ridge.
(4) People Always Net Rockfish:
Psoriasis, pitting nails, plaques, acanthosis, neutrophils, rete pegs and rete ridges prominent
Variants:
Guttate Psoriasis: salmon-pink papules on trunk and extremities.
Pustular: raised bumps filled with white blood cells. Skin around is red.
Erythrodermic: skin looks like it’s been burned. Dangerous in older folks.
Histology: Hyperkeratosis, Acanthosis, Spongiosis, Munro’s Abscesses (neutrophil accumulation in spinous and granular layer), thin suprapapillary plate, eosinophilic infiltrate
Lichen Planus symptoms and types
Inflammatory disorder
4 Ps: Pruritic, purple, polygonal, polymorphous papules.
Associated with prior exposure to Hep C; may be autoimmune. Found on ventral wrists and mouth.
Histology: Band-like lymphocytic infiltrate at dermal-epidermal junction. Civatte bodies. Acanthosis, Prominent granular layer, dense stratum corneum ,
Pityriasis Rosea
Inflammatory Disorder
Large herald patch followed by Christmas tree pattern plaques, following tension lines.
“Roses are plants and trees are plants”.
Histology: Epidermal spongiosis w/ parkeratotic caps.
System Lupus Erythematosus
Malar butterfly macular erythema on face. Anti-nuclear Ab test. Vacuolization of basal layer. Granular IgG along basement membrane zone. Multi-organ involvement
Discoid Lupus Erythematosus
Erythematous scaly papules and plaques in sunexposed areas. No systemic concern. Histology: chronic inflammatory infiltrate at Dermal/epidermal junction, basement membrane thickening. Need to protect with sunscreen.
Human Papilloma Virus (warts)
- Viral infection
- Verruca vulgaris - common warts. Histology: papillomatous epidermal hyperplasia w/ hyperkeratosis and hypergranulosis. Mostly exophytic grownth
- Verruca plana- flat warts
- plantar warts: pounded inwards
- Condyloma accuminatem- genital warts (via HPV 6 & 11)
- HPV 16 and 18 associated with development of squamous cell carcinoma
- Histology: squamous epithelial cells undergo structural changes and hyperplasia (become kiloctyes).
- No reliable treatment
Molluscum Contagiosum
- Viral infection
- Pox virus
- Also known as water warts
- Slightly translucent papules with keratotic center
- Diffuse in children
- STD in adults
Histology: Eosinophilic viral inclusions in keratinocytes compress and obscure nucleus
Herpes
Herpes Simplex:
-unilateral distribution
HSV1: above the waist. Oral herpes.
HSV2: below the waste. Genital Herpes.
Varicella Zoster Virus:
- Chicken Pox (first instance of varicella)
- Zoster (reactivation of varicella); AKA Shingles. Dermatomal Distribution
Histology: epithelial giant cells, multinucleate
Impetigo
- Honey colored rusting
- Most common in children
- Bacterial infection typically caused by staph or streptococcus (both are gram positive bacteria)
Histology: Subcorneal neutrophils with bacterial colonies.
Treatment: Penicillin
Syphilis
- Caused by a spirochete (a worm-like spiral-shaped bacteria) called Treponema pallidum.
- Primary Syphilis: occurs 1 week to 3 months post infection as a chancre (ulcer)
- Secondary Syphilis: occurs 2-8 weeks after disappearance of primary as body rash. Not always itchy
- Tertiary Syphilis: 5-10 years after secondary. Cardiovascular syphilis and neurosyphilis. Affects internal organs.
Congenital: if mother doesn’t get it treated.
Test: RPR flocculation test. Used to be VDRL
Treatment: penicillin is a cure.
Tinea corporis
Tinea Capitus
Tinea Cruris
Tinea Pedis
Tinea Facei
Tinea Onychomycosis
Pityriasis (Tinea) Versicolor
Coccidiomycosis (Valley Fever)
Fungal Infection.
Corporis: (Body) Ringworm
Capitus: Head
Cruris: jock-itch
Pedis: athletes foot
Facei: Face
Onychomycosis: fungus nails
Pityriasis (Tinea) Versicolor: Small discolored patches on skin.
Valley Fever: wide range of skin lesions. Pulmonary symptoms with very and can have CNS ad joint involvement.
Do not use steroids b/c decrease immune response to fight it.
Test: KOH
Histology: Dermatophytes in the stratum corneum
Lyme disease
From ticks that carry Borrelia burgdorferi.
Target shaped bite.
Scabies
Itchy contagious disease from mites burrowing in stratum corneum. Itching will kill them.
Urticaria
Erythematous wheals with surrounding pallor.
Angioedma - massive localized swelling
Hives
Treatment: antihistamines
Histology: Derma edma. Mediated by IgE on mast cells. Interstitial neutrophils and eosinophis.
Morbilliform Rash
Erythamtous papules coalescing into plaques.
Allergic reaction to drugs in adults.
Ex. Water pill allergy
Histology: superficial vasodilation, perivascular lymphocytes.
Erythema multiforme
Blistering disorder
Target lesions often on palms or soles.
Serious form has mucosal lesion, (SJS)
Triggered by infections. Most commons is by Herpes Simplex.
Inflammatory cascade triggered by Langerhans cells.
Histology: Vacuolization of basal layer with apoptosis
Stevens-Johnson Syndrom/Toxic epidermal necrolysis (TEN)
Blistering disorder
Widespread blisters on trunk and face.
Erorsion of mucous membrane.
TEN is worse; blisters covering at least 30% of body.
Cause: in adults from allergic drug reaction.
Histology: Appears to be cell mediated immunity against keratinocytes triggered by CD8+ cytotoxic T cells and granulysin.
Dermatitis herpetiformis
- Blistering disorder
- Pruritic groups of blisters on extensor/dorsal surfaces.
- Associated with gluten-sensitive enteropathy.
Treatment: gluten free diet.
Histology: Papillary dermal neutrophilic microabcesses.
Granular deposits of IgA near DE junction within dermal papilla creating inflammatory response.
Melasma
Patchy pigment on face.
“Mask of pregnancy”
Histology: pigment in epidermis and/or dermis
Vitiligo
- White patches
- Complete loss of pigment
- Loss of melanocytes and pigment
Michael Jackson had it.
-Type IV Hypersensitivity - T-cell Mediated Disease
Albinism
- Absence of pigment in skin, hair, and nails.
- Autosomal recessive
- Melanin still present but it doesn’t work
Seborrheic Keratosis
- “Stuck on “ lesions
- sometimes inflamed or bleeding from picking.
- Histology: May have keratotic pores or pseudocysts.
- Variable size.
- Not related to sun exposure
- uneven pigmentation
Melanoma
- Tumor of melanocytes.
- Superficial spreading melanoma: most common. Grows on top layer of skin before spreading.
- Nodular Melanoma: invades bottom layer early, most serious.
- Mutations with P53 (Tumor Suppressor) or BRAF (oncogene)
- CDKN2A and CDK4 involved in familial melanoma.
Histology: Large variable nuclei, pagetoid (upward spreading) migration upward in epidermis, and
mitotic figures,
Acanthosis Nigrins
- Dark patches in interginous areas and neck.
- Common in people with obesity, and insulin resistance.
- May be associated with internal tumors but rarely.
Cafe au lait/neurofibromatosis
- Cafe au lait spots are benign light brown macules
- increase pigment in basal layer.
- multiple lesions (more than 6) associated with neurofibromatosis (tumors forming on nerve tissue)
- Benign spindle cell tumor of Schwann cells and fibroblasts.
Solar (actinic) elastosis
UV light damages collagen and elastic fibers in dermis. Causing skin wrinkling.
aka: Actinic keratosis
Bullous Pemphigoid
Type II Hypersensitivity: Antibody against cell surface antigens
Pemphigus vulgaris
Type II Hypersensitivity: Antibody against cell surface antigens
Systemic sclerosis
Type IV Hypersensitivity - T-cell Mediated Disease
Lentigo
Histology: exaggeration of rete ridges in lentigo area compared to surrounding normal skin. Melanocyte hyperplasia in basal layer. melanophages found in dermis (melanocytes eated by macrophages) aka pigment incontinence. Dirty sock appearance.
Basal Cell Carcinoma
Mechanism: involves PTCH mutation (tumor suppressor gene)
Histology: Telangiectasia, invasion of dermis and peripheral palisading at edge of lesion. Stroma retraction at dermal-epidermal layer. Little metastatic risk.
Intradermal Nevus
Histology: nevus clusters in superficial dermis with maturation with descent.
Melanoma
Histology: Cluster of atypical melanocytes in dermis and epidermis above basal layer (pagetoid spread). Red nuclei.
Squamous cell carcinoma
Histology: Keratin Pearls and invading kerotincytes with intercellular bridges in dermis.
Actinic Keratosis
Crusty scaly growth due to sun damage. Dysplasia is seen in epidermis. Cells have high N:C ratio
Solar elastosis (basis for wrinkling) can be seen: accumulation of bluish elastin
Papillomatosis and koilocytes a feature of?
HPV infection
