Dermatopathology Flashcards
Hyperkeratosis
Thickening of the stratum corneum
Parakeratosis
Flattened, keratinocyte nuclei within the stratum corneum, where nuclei are not normally present
Orthokeratosis
Hyperkeratosis of anuclear keratinocytes within the stratum corneum
Acanthosis
Thickened stratum spinosum
Acantholysis
Loss of cohesion between keratinocytes due to dissolution of intercellular connections
Dyskeratosis
Abnormally or prematurely cornified (keratinized) keratinocytes in the epidermis that stain pink on H&E
What are the layers of the epidermis?
“Cancel labs get some beer”
Stratum Corneum Stratum Lucidum (thick skin only - palms and soles of feet) Stratum Granulosum Stratum Spinosum Stratum Basale
Papillomatosis
Irregular undulation of the epidermal surface
Solar Elastosis
Accumulation of basophilic (grey/blue) matierial in the upper dermis due to sun damage
Papule
Elevated skin lesion
Macule
Flat skin discoloration
Ichthyosis Vulgaris
A disorder of dry, scaly skin due to defective desquamation that leads to build-up into a compacted scale. Often described as “fish scales.”
What is the inheritance pattern of ichthyosis vulgaris?
Autosomal dominant mutation
Presents with severe, thick plates of scale that almost resemble reptile scales and present at birth. Mostly affects palms, soles, and flexures.
Lamellar Ichthyosis
What is the inheritance pattern of lamellar ichthyosis?
Autosomal recessive mutation
X-linked Ichthyosis
Presents as more brownish and scaly eruption in males, usually in early childhood.
What is the mutation in X-lined ichthyosis?
Mutation in STS gene leads to defective steroid sulfatase
Seborrheic Keratosis
Papillomatosis, acanthosis, and horn cyst formation. Present as stuck on plaques or verrucous lesions
Leser-Trelat Sign
Sudden onset of multiple seborrheic keratosis that is indicative of paraneoplastic syndrome and metastatic cancer
Acanthosis Nigricans
Lacks acanthosis and horn cyst. Clinically presents as a velvety plaque most common on the back of the neck or axilla.
What are fibroepithelial polyps AKA?
- Skin Tag
- Acrochordon
Common scaly erythematous patch located on sun-damaged skin - Increasingly common with age
Actinic Keratosis
What is actinic keratosis a precursor for?
SCC
What is the “flag sign?”
It is seen in actinic keratosis - Basal layer atypia with overlying parakeratosis alternating with orthoparakeratosis.