Ch. 15 - Disorders of skin appendages Flashcards
What conditions comprise the non-inflammatory alopecias?
Pattern alopecia (androgenetic balding)
Telogen effluvium
Trichotillomania
Tration alopecia
Pattern alopecia (androgenetic balding)
Miniaturization of follicular units with variability in diameter of follicles and decreased anagen:telogen ratio.
Telogen effluvium
(cause?)
Many telogen hairs. No miniaturization of pattern alopecia.
(interruption of anagen growth, eg febrile illness or crash diet)
Trichotillomania, traction alopecia
Empty anagen follicles, apoptotic keratinocytes in catagens, melanin casts, and trichomalacia.
What conditions comprise the inflammatory non-scarring alopecias?
Alopecia areata
Syphilitic alopecia
Alopecia mucinosa
Folliculotropic mycosis fungoides
Tinea capitis & Majogcchi’s fungal folliculitis
Acne vulgaris
Alopecia areata
Lymphocytes targeting melanocytes in the hair bulb (peribulbar infiltrate). Follicular miniaturization, melanin casts and eosinophils.
Syphilitic alopecia
Identical to alopecia areata (peribulbar inflammation), may contain plasma cells.
Alopecia mucinosa
Mucin within follicular epithelium and variable surrounding lymphoid infiltrate. Can be associated with mycosis fungoides.
Folliculotropic mycosis fungoides (cutaneous T-cell lymphoma)
Abnormal lymphocytes in the follicular epithelium (surrounded by white space). Papillary dermal fibrosis. CD7-.
Tinea capitis, Majocchi’s fungal folliculitis
Mixed inflammatory infiltrate. Fungal spores within or surrounding hair shaft.
Acne vulgaris
Infundibulum filled with laminated keratin and debris. Suppurative inflammation.
What conditions comprise the cicatricial alopecias?
Lupus erythematosus
Lichen planopilaris
Idiopathic pseudopelade
Central centrifugal cicatricial alopecia (CCCA)
Dissecting cellulitis
Folliculitis decalvans
Lupus erythematosus
Lymphoid infiltrate at the isthmus. Interface dermatitis. Hyperkeratosis. Perivascular/periadnexal infiltrate. Granular DIF.
Lichen planopilaris
Lymphoid infiltrate at the infundibulum. Lichenoid interface dermatitis. Civatte bodies. DIF with linear fibrin and cytoid bodies.
Idiopathic pseudopelade
Shrunken deep red “contracted” dermis with broad fibrous tract remnants. Thick elastic fibers.
Dissecting cellulitis
Clinically similar to nodulocystic acne, with deep dermal and subQ abscesses & granulation tissue.
Folliculitis decalvans
Suppurative folliculitis with wedge-shaped scar. Resembles Staph folliculitis.
Langerhans cell histiocytosis (histiocytosis X)
Perifollicular epithelioid histiocytes with edema & eosinophils.
Histiocytes stain with S100, CD1a, langerin. Birbeck granules.
Chondrodermatitis nodularis helicis
Central ulcer with fibrin core and granulation tissue. Essentially a decubitus ulcer.
Neutrophilic eccrine hidradenitis
Neutrophils within eccrine coil. Often noted during induction chemotherapy.
Hidradenitis suppurativa
Suppurative folliculitis with abscess formation and sinus tracts with suppurative/granulomatous inflammation. Granulation tissue.
Mucocele
Pooled mucin adjacent to minor salivary gland with variable granulomatous response.
Pattern alopecia (androgenetic balding)
Telogen effluvium
