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Flashcards in Dermatology Deck (134)
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31

Prognostic factors of melanoma

Most important= Breslow thickness
- Measured from the granular cell layer to the deepest penetration of the neoplasm
- Survival decreases with increasing tumor thickness

Melanoma ulceration
- Marker for aggressive nature of lesion
- Nodular lesions
- Up stage equivalent to one T level

Mitosis
- New prognostic factor as of 2009
- Proliferation of the primary melanoma
- Threshold considered significant is greater than 1 mitosis per mm2
- Adversely influences survival
- Melanoma measuring < 1mm in thickness

Anatomic site
- Worse prognosis: Head and neck, Trunk, Hand and feet; Five-year survival 84%
- Better prognosis: Arms and legs; Five-year survival 93%

Age
- Increasing age--> decreasing survival
- Patients older than 50 years of age have a 84% five-year survival vs. 90% for younger patients

Gender
- Female patients have a better survival
- Female five-year survival 90%
- Men five-year survival 83%

32

Prognostic factors in regional metastases

Status of regional lymph nodes most powerful prognostic factor for survival
- Presence of regional lymph nodes portends a worse prognosis
- Number of lymph nodes involved is the most significant risk factor

The second most important risk factor is tumor burden
- Micrometastatic disease (SLN Bx) vs. macrometastatic disease (clinically palpable disease)

Worse prognosis:
- Ulceration
- Satellites
- Both clinical and microscopic metastasis around a primary melanoma
- In-transit metastasis: Intralymphatic metastases between the primary tumor and its nodal basin

33

Prognostic factors in distant metastases

Site of metastasis – most important factor
- Visceral metastases poorer prognosis than non-visceral (skin, subcutaneous tissue, distant lymph nodes) sites
- Number of metastases
- Amenable to surgical resection

34

Psoraisis Vulgaris

Pathophys:
- Multifactorial disorder with genetic predisposition
- New immune cell recognised: TH17 cell--> increased IL 17 causing increased keratinocyte proliferation--> chemokine release--> skin defense

Risk factors:
- Strep pharyngitis
- Stress
- Skin trauma (scratches): Koebner phenomenon


Features:
- Nail pitting (v. difficult to treat)- increased risk of psoriatic arthritis
- Morning stiffness

35

Psoriasis Inversa

Skin fold regions (inverse of expected region)
Does not have silver plaques

36

Erythroderma

Defined by erythema and desquamation involving more than 90% of skin surface

Differential:
- Skin eruption
- Infection
- Allergic reaction

37

Pustular psoriasis

May be systemically ill
- Need to be followed/assesed for: hypocalcemia, hypotension, fever

Care must be given with systemic steroids as taper--> pustular flare

38

Psoraisis treatment

Local:
- Corticosteroids
- Vit D analogues
- Tar

Phototherapy:
- PUVA
- Narrowband UVB

Systemic:
- Retinoids (push cell differentiation)
- Methotrexate
- Cyclosporine
- Mycophenolate mofetil
- TNF-alpha inhibitors for psoriatic arthritis

39

Atopic dermatitis

3/4 major features:
1. Prutitus
2. Typical morphology and distribution
3. Chronically relapsing
4. Personal or family history of atopy

Usually not before 3 months of age
- Relies on patient sratching it

In infancy:
- face= common site
- sites where they can rub against bed, reach easily
- May see failure to thrive

Childhood/adulthood
- Flexural surfaces= common sites
- Chronic involvement can lead to lichenification (skin thickens)

Features:
- White dermatographism (not red wheal, but white wheal)

Theory behind pathophys:
- Immunologic abnormalities (humoral immue, t-cell mediated immune response)
- Structure of skin abnormal (BAD skin)
- Defect in humoral immune response: high levels of serum IgE, binding to langerhaans cells
- Antigen-induced activation of IgE-bearing cells (mast cells, macrophages)
- Decrease in cyclic AMP--> hyperreactive mast cells, Langerhans' cells

Exacerbating factors:
- Anxiety, stress
- Climatic factors: temps, humidity
- Irritants: detergents, solvents, wool/rough material
- Food, contact, inhaled antigens

40

Itch-scratch cycle

Pruritis precedes visible eruption
- C-fibers transmit itch first
Scratching--> increased release of histamine from mast cells--> pruritis

41

Differential diagnosis of Atopic dermatitis


Differential diagnosis:
- Psoraisis, scabies, eczema
- Wiskott-Aldrich (eczema, thrombocytopenia, immunodeficiency)
- Hyper-IgE (cold staph abscesses- not painful/hot, eczema-like rashes, lung infections)
- Cutaneous T-cell lymphoma

42

Seborrheic Dermatitis

Earlier onset=typical
Absent pruritis
Limited distribution on face, groin

- Greasy scaly macules and patches on the central part of the face (nose, mouth, and eyebrows).
- Scalp is a common site of involvement, which the patients complain of bad “dandruff.” The condition is seen in neonates (e.g. cradle cap), which resolves when the maternal hormones are washed out.
- The condition is usually not seen in prepubescent age. In adults, the condition is more common in patients with neurologic diseases such as Parkinson’s disease.

Cause: belief that condition is caused by a commensal fungus, namely, Malesezzia furur.

Treatment: antifungal creams and shampoos are often recommended such as ketoconazole cream and shampoo. Other treatments include zinc based soaps and shampoos, immunomodulators such as pimecrolimus, and low potency steroid.

43

Scabies

Papules, burrows, nodules
Distribution:
- Infants= generalized
- Adults: finger webs, wrists, exillae, groin

Pruritis in patient and contacts
Mite debris on microscopic examination

44

Eczema herpes

Disseminated Herpes Simplex Virus (HSV)
Painful umbilicated pustular vesicles
Fever, malaise, lymphadenopathy
Significant morbidity and mortality (risk of systemic herpes infection)

Seen in patients with atopic dermatitis or other chronic skin conditions:
- dissemination of the cutaneous herpes simplex virus into the eczematous skin may lead to the eruption of clusters of umbilicated pustular vesicles known as eczema herpeticum or Kaposi's varicelliform eruption

45

Impetigo

Pustular vesicles with straw-colored discharge
- Due to staph aureus infection

46

Treatment for atopic dermatitis

- Topical steroids or immune modulators: tacrolimus, pimecrolimus
- Antihistamines
- Wet wraps
- Coal tar in ointment base, anthralin
- Antibiotics (topical, oral)
- Leukotriene antagonist

Flares:
- PUVA, UVB
- Systemic steroids
- Immunomodulators (cyclosporine, tacrolimus, azathioprine)

47

Lichen planus

Pruritic disorder of skin, mucous membranes
Appearance: violaceous polygonal papulaes, plaques on penis
- Hypertrophic or erosive

Oral mucosa with typical white reticulated plaque
- Associated with HCV

Erosive lichen planus= increased risk of squamous cell carcinoma in oral/mucosal lichen planus
- v. painful, can cause scarring/disfigurement

48

Lichen Nitidus

Variant of lichen planus
Seen in children
- non-pruritic

49

Acne keloidalis nuchae

Chronic folliculitis--> scarring ressembling keloids in darker-skinned individuals

50

Abscesses

Cause: Staph
- Furuncle= single follicle
- Carbuncle= multiple follicles

Treatment with I&D and antibiotics
- Chronic abscesses due to carriage

51

Hidradenitis Suppurativa

Inflammatory non-infectious process
Multi-focal and symmetric involving 2+ locations
- Treatment is difficult, scarring results

52

Epidermal cysts

Firm, mobile nodules
Treatment: I&D

53

Scarlet Fever

More common in kids, caused by Group A strep erythrogenic exotoxin
- 24-48 hours after sore throat
- Sandpaper-like papules
- Pastia lines, desquamation of palms and soles

Diagnosis: strep culture, ASO

Treatment: antibiotics

54

Erysipelas

Group A strep (except in post-partum/newborns= Group B strep)
- Infection of superficial dermal lymphatics from lacrations
- Erythematous, brawny plaque on face, legs

Treatment: oral antibiotics

55

Cellulitis

Staph or strep
Port of entry: tinea pedis in toes

Usually unilateral, can be bullous

Treatment: IV antibiotics

56

Stasis Dermatitis

Chronic venous stasis--> extravasated RBCs
- Erythema, yellow-brown plaques with lichenification
- Often bilateral

Treatment: compression, topical steroids

57

Erythema migrans

Borrelia burgdorgeri= Lyme disease
- 3-32 days after bite as papule--> annular
- 25-50% develop multiple lesions
- Fades without treatment

Treamtent (for Lyme): doxycycline

58

HHV 3

Varicella= Chicken pox

Herpes Zoster

59

HHV5

Cytomegalovirus

In adults: similar to EBV infection
In neonates: TORCH syndrome
- Blueberry muffin baby

Can also co-infect with HSV

Treatment: gangciclovir

60

HHV6

Roseola
- Self-limited, seen in babies

Pityriasis Rosea:
- Viral exanthem
- 20% have mild flu-like symptoms
- begins with 2-10 cm oval, scaling patch for 1 week--> followed by smaller oval patches (cigarette paper scale "christmas tree")
- Treatment: topical steroids for itch (rash recedes on its own

* Mimicker= secondary syphillis (6-8 weeks post-chancre)