Dermatopathology part 6 Flashcards
Panniculitis
inflammation of fat lobules or the connective tissue septa separating fat lobules
Erythema nodosum: Etiology, SX
inflammatory reaction of hte connective tissue septa separating fat lobules
most common in females 20-30
not a disease but a reaction to various etiologies
self limited resolution in 6 weeks
fever malaise and joint pain may precede the rash
ERythema nodosum: gross
painful, red, subcutaneous, elevated nodules
nodules are indurated and poorly circumscribed
usually located on the anterior aspect of the tibia
bilateral but not symmeteric
Erythema nodosum causes
idiopathic
strep infection
sarcoidosis
inflammatory bowel disease
fungal infection
pregnancy
meds: OCP, sulfa, amiodarone, antibiotics
syphillis
TB
Erythema nodosum: TX
bed rest, lega elevation, NSAIDS, and heat for SX. Steroids only when infection excluded
Erythema nodosum histo
septal panniculitis (little to no necrosis of lobule)
Early: widening of septa from fibrin edema and neutrophilic infiltrate
chronic: mononuclear cells and granulomatous inflammation of septum with fibrosis
Warts
benign growths caused by infection of epidermal cells with human papilloma virus
generally occur in children and yougn adults
transmitted by skin to skin contact
lesions disrupt skin lines
intralesional brown black dots are pathogenomic and reprsent thrombosed vesels
Wart gross: the common wart (verruca vulgaris)
the common wart (verruca vulgaris)
flesh colored papule with hyperkeratotic surface
most common on elbows, knees, fingers, palms
Wart gross; Flat wart (verruca plana)
flesh colored, slightly raised papules and flat surface
usually on chin, dorsum of hands, and legs
Wart gross: Plantar wart (verruca plantaris)
HPV 1
fleshed colored papule with hyperkeratotic surface
warts found on underside of foot. may cause pain if on pressure areas.
Warts: Anogenital wart (condyloma acuminatum)
Most common STD, types HPV 6 and 11
HPV 16 and 18 can lead to cervical cancer
appearnce: soft, fleshy pink papillomas on the genitalia, perineum , and anus.
Verruca vulgaris histo
exophytic
chruch spire of verrucous acanthosis
koilocytes (cells with vacuolated cytoplasm- clearing around the nucleus)
infected cells may show prominent keratohyline granules
Warts sx
most warts are asymptomatic
may bleed
most disappear in 1-2 years but may mutiply or recur despite treatment
Warts TX
cryotherapy may need > 1 treatment, 60-75%
duct tape: more effective than cryo in some studies
salicyclic acid
5 fu
imiquimod
pdophyllin for genital warts
pare lesion down or soak to allow better penetration of topical medication
Molluscum contagiosum
common, self limited viral infection in kids and sexually active adults
caused by poxvirus
transmitted via skin to skin contact and is highly contagious
Molluscum contagiosum: SX
asymptomatci smooth, dome shaped papules with central umbilication
lesions are flesh colored and translucent
papules ahve a cheesy core that can be expressed
may occur singly or in groups
occur anywhere on kids and genitals of sexually active adults
Molluscum contagiosum TX
spontaneously remit in a few months
In HIV patients, lesions can be extesnive, grow very large and be refaractory to treatment
TX: cryotherapy, curettage, salicyclic acid
Molluscum contagiosum: Histo
cup shaped lesion with scallped border
verrucous acanthosis (epidermal hyperplasia)
molluscum bodies in cells of stratum corneum and stratum granulosum (ovid, homogeneous, cytoplasmic inclusion bodies)
Impetigo
Common, highly contagious superficial bacterial infection of the skin
children, adults
painful lesions distinguishes from contact dermatitis
two forms nonbullous and bullous
Staph a. is most common cause of either kind
Impetigo: Nonbullous
most common
face and extremities
papules progress to vesicles on erythematous base
when vescicles rupture causes typically “hone colored rust”
Impetigo: Bullous
young children
vesicles enlarge to form flaccid bullae with clear yellow fluid contents, later becomes darker and more turbid; ruptured bullae leave a thin brown crust
trunk is more frequently affected
Impetigo Histo
accumulation of neutrophils beneath stratum corneum
Impetigo TX
topical: Mupirocin or hydrogen peroxide cream for limited number of lesions
oral antibiotics for bullous type
Scabies
infection with sarcoptes scabiei
common in school age children, nursing home patients, and less developed countries
patients present with the worst itch they;ve ever had
incubation time is about 1 month so contacts may not be symptomatic
Scabies sx
predilection for finger webs, wrists, and penis
spares head, neck, palms, and soles
linear burrows with a drak dot at one end representing apth of female mite in skin
small inflammatory papules and excoriations predominate
Scabies (sarcoptes scabiei)
highly contagious: skin contact, towels, linens
mites tunnel in epidermis, lay eggs, and deposit feces. Very few mites present
eggs and feces cause delayed type IV hypersensitivity reaction causing intense itching usually at night
Scabies diagnosis
look for burrows on hands, wrists, etc
suspect in anyone with persistent generalized, severe pruritis
confirm diagnosis by scraping burrow with a scalpel. Look under microscope to detect mites, ova, or feces
Scabies oil preparation
put a few drops of mineral oil on glass slide
put mineral oil on scalpel blade
scrape burrow with blade
put scrapings on slide
look under microscope
Sccabies TX
topical: 5% permethrin cream, 1% lindande lotion
oral ivermectin
treat all close contact and wash all linens and underwear
not contagious after 1 treatment. itching may alst for weeks as mites are shed. use topical steroids and oral antihistamines
Xanthelasma (xanthoma
collection of macrophages containing lipid droplets
assocaited with familial hyperlipidemias, nephrotic syndrome, myeloma, pnacreatitis, thryoid disease, primary biliary cirrhosis
may be isolated findings. Always check lipids
mongolian spot
single gray-blue lesion over lumbosacral area
more common in asian and native americans pts
melanocytes lcoated in the dermis instead of epidermis that may be neural crests cells interrupted in migration
most disappear during childhood.
no melanomas occur in this lesion
cherry angioma
bright red , domed, vascular lesions on trunk
benign and increase with age
TX not indicated
Hemangioma of infancy
most common tumor of infancy
most common in premature, caucasian girls
benign tumor of hyperplastic blood vessels
blachable bright red to deep purple lesions
arise in the first few weeks of life and grows for the first year then regresses normally by 10.
Hemangioma of infancy
do not treat unless it ulcerates or blocks ears, eyes, larynx
can use propranolol, steroids, or laser
parents need a lot of reassurance
Alopecia
3 phases of hair development: anagen (grwoing) catagen (involution), telogen (resting and hair shed at end)
Alopecia androgentic alopecia
polygenic inheritance
involves scalp 5 alpha reductase activity and androgenic effects of dihydrotestosterone produced
men and women equally affected
men: loss at temporal areas and mid scalp
women: diffuse loss, rarely complete, front hairline maintained
Alopecia: tinea capitis (ringworm)
isolated pruritic lesion on scalp with central clearing
Alopecia Telogen effluvium
diffuse decrease in ahir density due to rapid conversion of anagen to telogen hair
precipitate by stressful events, illness, fever, pregnancy
Aloipecia areata
autoimmune disorder causing patchy or diffuse hair loss
alopecia TX
alopecia areata: high potency topical steroids
androgentic alopcia: minoxidil and finasteride (inhibits syntehsis of dihydrotesterone.)
spirnolactone in women.
Xeroderma pigmentosum
autosomal recessive condition
decreased ability to repair DNA followed damage by UV light due to defects in excision of abnormal nucleotides or defects in replacement of nucleotides following excision
first year of life with erythema, scaling, subsequent hyperpigmentation and lentigo on lgiht exposed area
skin later shows atrophy, teleangiectasia and intermingling areas of hypo and hyperpigmentation
squamous cell cancer, basal cell cancer and melanoma develop as early as 50-60 years of life
Chediak higash syndrome
autosomal recessive
immunodeficiency due to defect in neutrophil phagosome lysosome fusion causing abnormal giant lysosomal inclusions visible on peripheral blood smear. Pyogenic infection due to staph and strep.
Albinism: abnormal melanin sotrage in melanocytes causes aprtial oculocutaneous albinism
nystagmus, peripheral and cranial neuropathies
most commonly diagnosied in childhood.
Wiskott aldrich syndrome
x linked disorder
immunodeficiency
eczema
thrombocytopenia
combined B and t lymphcyte disorder
albinism
melanocytes normal in number and location but production of melanin defective due to complete absence of tyrosinase
complete albinism manifest by white hair, blue eyes and pink or white skin.
