Dermatology Flashcards
Management options for Acrochordon/fibroepithelial polyp
- No treatment
- Removal of lesions
The commonest dermatologic cyst
An epidermoid cyst (Sebaceous cyst/epidermal cyst/ epidermoid inclusion cyst/Pilar cyst)
Appearance and feel of Epidermoid cyst
- Firm to soft regular lump (usually round)
- Fixed to the skin
- A central pore or punctum may be present.
Location of epidermoid cyst in decreasing frequency
- Scalp»»Face»>Neck»Trunk>Scrotum
Origin of epidermoid cyst
Hair follicles
Management options for Epidermoid cyst
- No treatment
- Surgical removal
- Antibiotics, I&D, steroids for inflamed cyst
A superficial scalp nodule, lobulated with defined edges, mobile but stony feel to palpation
Pilomatrixoma
Diagnosis of Pilomatrixoma
- Tent sign
- Skin crease sign
- Ultrasound evidence of Calcification
Treatment of choice for Pilomatrixoma
Surgical excision, with margins of at least 1–2 cm
Cyst caused by puncture injury
implantation cyst
Features distinguishing implantation cyst from epidermoid cyst
- Absence of a punctum
- Age of the patient (Adults)
Management of implantation cyst
Surgical removal (incisional removal)
Management of choice mucoceles
Spontaneous resolution in 2-3 weeks
Ranula (mucocele of the sublingual gland) is managed by
removal of sublingual gland
People at risk for developing keloids
- Past hx of keloids
- Family hx of keloids
- People of colour
Treatment of choice of scarring (keloids or hypertrophic scar)
Intralesional Steroids
Commonest sites of Common warts
- Hands
- Feet (plantar)
- Extensor surfaces
Commonest sites of Plane (flat) warts
- Face
- distal limbs
HPV implicated in common warts
1,2,4,27 and 57
HPV implicated in plane warts
3, 10
HPV implicated in genital warts
6 and 11
Initial Management of common warts and plane warts -(other than the face).
- No tx (most resolve within 2 yrs
- 1st line - Salicylic acid plus or minus lactic acid
- 2nd line - Liquid Nitrogen
Treatment options for recalcitrant warts
- Destruction TX:
(Aggressive cryotherapy, electrosurgery, Laser TX) - Intralesional chemotherapy
- Intralesional immunotherapy
Treatment of facial Plane warts
- No TX (resolves within 12 months)
- Topical retinoid
Important lesion that can be confused with Seborrhoeic Keratoses
Lentigo maligna melanoma
Treatment of seborrheic Keratoses
- no TX
- destructive techniques (Cryotherapy, Ablative laser)
Treatment of choice for molluscum contagiosum
Spontaneous resolution (in 6-9 months or longer)
Prevention of Molluscum contagiosum spread
1- Avoid using the bath
2.- avoid bathing with others
3.- Avoid sharing towels with others
TX options for pyogenic granuloma (granuloma telangiecticum)
- 1st line-Surgical
(excision, curettage, shave excision) - Next line: cryotherapy or ablative tx
- No TX (spontaneous resolution)
Characteristic feature of dermatofibroma
Dimple sign on pinching margins
Treatment options for dermatofibroma
- Reasurrance
- Surgical excision (on request or rapidly enlarging nodule)
Prevalence of actinic (Solar) keratoses In Australia
-40-50% in over 40 year olds
- more than 80% in the 7th decade
Risk of progression of Actinic keratoses to SCC
LOW= 0.075-0.096% per year
Tx options for actinic keratosis
- Prevent further sun damage
(Sunscreen, appropriate clothing - Lesion specific therapy
(Cryotherapy with liquid nitrogen (T-o-C), curettage (+or- cautery) & shave excision). - Field Therapy
(5-FU,Diclofenac, PDT, Imiquimod)
A rapidly growing lesion on sun-exposed skin with smooth outer dome and a central keratin plug
Keratoacanthoma
Keratoacanthoma can be confused with?
SCC
Recommended treatment for Keratoacanthoma
Surgical excision with 2-4mm margin
Management of Lipoma
- Reassurance
- Surgical excision (cosmetic reasons or to relieve discomfort from pressure)
Multiple soft (or rubbery), lobulated mass located in the subcutaneous tissue of a woman with similar hx in her mother
Lipoma
A Solitary firm, painless, subcutaneous lumps invaginated with direct digital pressure (‘ the buttonhole sign) is?
A neurofibroma
Incidences of skin cancers in Australia
- BCC-80%
- SCC- 15-20%
- Melanoma < 5%
Skin cancer type associated with most deaths
Melanoma
High risk factors for melanoma
- > 5 dysplastic naevi
- > 100 simple melanotic Naevi
- Personal hx of previous melanoma
Most common location of melanoma in men & women.
Women- Lower limbs
Men- Upper back
Red flag pointers of melanoma
- New or changing lesion
- A Prominent pigmented lesion that stands out
- A Rapidly growing nodule of any color
- Non-healing lump or ulcer
- A lesion that concerns to the patient
- Dermoscopic changes on ff up or poor dermoscopic-clinical correlate
Prognostic factors of melanoma
- Thickness of lesion
- Length of lesion
- Site of lesion
- Sex, Age, Amelanotic melanoma & ulceration
Breslow classification of melanoma thickness
Clark I: tumor thickness =0mm
Clark 2: < 0.76mm= 5yr survival rate of 95%
Clark 3: 0.76-1.5mm= 70-98%
Clark 4: 1.51–4.0mm= 55–85%
Clark 5: > 4.0mm =30–60%
Diagnosis of Melanoma
Clinical exam by Maggylamp & dermoscopy
Features of melanoma lesion on dermoscopy
A = Asymmetry
B = Border= well defined & irregular
C = Colour= classically= blue–black.
D = Diameter= when first seen, most are ≥7mm
E = Evolution &/or Elevation= indicates invasion & is a sign of more advanced dx
Management of choice for Melanoma
Excision
Excision margin for melanoma
Is based on the thickness of lesion
- Melanoma in situ (lentigo maligna) — excision margin = 5 mm
- <1 mm thick—excision margin=1cm
- 1–4 mm thick– excision margin of 1cm-2cm
- > 4 mm thick, excision margin ≥2 cm
Management of a suspected melanoma (diagnosis unsure)
- Local excision biopsy with 2 mm margin to mid-fat layer for histology
- If other diagnosis; No further excision
- If melanoma is diagnosed; re-excised as per the thickness rule
What are follow-up rules for melanoma after tx
- 1 mm thick = 6 monthly reviews for 2 years
- 1–2 mm thick = 4 monthly for 2yrs, 6 monthly for next 2yrs, then yearly for 10yrs
- > 2 mm thick = review by both specialist and GP, regularly, for 10 years
- A yearly CXR is advisable.
Commonest sites of BCC
Mostly on sun-exposed areas:
Face (mainly), neck, upper trunk, limbs (10%)
Pattern of spread of BCC
A slow-growing tumor that spreads locally (not via lymph nodes or blood)!!!
Management of choice for BCC
Best: Simple elliptical excision (3–4 mm margin)
Other treatment options for BCC
- Mohs micrographic surgery
- Radiotherapy: frail people
- Photodynamic therapy
- Cryotherapy (avoid head & neck)
- Imiquimod 5% cream
Indications for Mohs micrographic surgery for BCC
o Mohs micrographic surgery
- Large or recurrent tumors
- Located where tissue conservation is required. (nose, eyelid & around the eyes, center of face)
- Infiltrative (morphoeic / micronodular subtypes)
- Poorly defined, so the extent of the tumor is not obvious clinically
Commonest sites of SCC
Mainly on sun-exposed areas (head, neck, back of hands, limbs, upper trunk)
Pattern of spread of SCC
- A fast-growing tumor capable of Metastases & involves regional lymph nodes
Origin of SCC
- De novo
- Premalignant lesions
Premalignant lesions of SCC
- Solar (actinic) keratoses
- keratoacanthoma
- Bowen disease
- Burns/chronic ulcers/leucoplakia
Treatment of choice for SCC?
Early Surgical excision with a 3 to 4 mm margin
(Wedge excision for SCCs of the ear and lip)
Other treatment options for SCC
- Specialized surgery &/or radiotherapy if large/in difficult site/lymphadenopathy
Post-excision follow up of SCC
Follow-up every 3-6 months for at least 2 years
A 20 year old girl with underlying history of inflammatory bowel disease and painful arthropathy of digits presents with non-itchy chronic red-silvery rash on the the extensor surfaces of elbows and knees that improves on sun exposure, there was similar hx in mother?
Psoriasis
Aggravating factors for Psoriasis
- Trauma (or physical stress, emotional stress, sunburn, winter)
- Infection (esp. GAS)
-Puberty/menopause
-Smoking - Drugs (BB, CQuine, Li, NSAIDs, OCPs)
commonest type of Psoriasis
Plaque (80%)
Diagnosis of psoriasis
- Clinical (biopsy may be needed to confirm diagnosis & r/o differentials)
Mainstay of treatment for Psoriasis
Topical Steroid
Initial recommended treatment for mild to moderate psoriasis
- Night: Dithranol 0.1+salicylic acid 0.3% +/-LPC (tar) 10% in paraffin or sorbolene cream
- Morning: Topical fluorinated corticosteroid (e.g. betamethasone) after shower
Treatment of Chronic stable plaque psoriasis
stronger fluorinated steroid +tar+ salicylic acid in sorbolene cream overnight or Calcipotriol or Calcipotriol+steroids
Tx of resistant localized plaque
Intralesional steroid injection (Triamcinolone)
Tx of severe psoriasis
- Systemic treatments: Chemotherapy: MTX/cyclosporine/Steroid/Acitretin
- Biologic: anti TNF agents, monoclonal antibodies
- Physical: Narrow band UV-B photo-therapy / photo-chemotherapy (Psoralen and UV-A).
Adjunctive management of psoriasis
- Exercise, rest, holidays preferably in the sun (No sunburn)!!!
- Avoid smoking
Conditions associated with Psoriasis
- CVS dx, DM, Obesity
- Depressive illness
- Arthritis, IBD, lymphoma
what makes an Acne mild?
Primarily composed of comedones + or - papules.
What are the features of moderate Acne?
- non-inflammatory comedones+inflammatory lesions (including papules
and a few pustules).
What are the features of moderate to severe Acne?
- Numerous comedones, pustules and papules +or- a few cysts or nodules.
What are the features of Severe Acne?
As for moderate to severe Acne + numerous nodules and/or cysts
How to treat Mild Acne?
Comedonal:
-1st line= Topical Retinoid
-alternative= Salicylic acid
- Inflammatory acne:
1st line=Top. Retinoid+BPO or BPO /Topical Ab.
How to manage Moderate Acne?
-1st line: BPO/topical AB
or Topical retinoid+BPO
-alternative (females): Hormonal therapy
±BPO/topical AB
or Topical retinoid
Management of moderate to severe Acne?
1st line: Topical AB + BPO + topical retinoid or
Oral AB + BPO +topical retinoid
Alt: Oral isotretinoin
Alt: (females) : Hormonal therapy ± BPO/topical AB
or Topical retinoid
Treatment of Severe Acne?
1st line: Oral isotretinoin
Alt (all): Oral AB+topical retinoid+BPO
or BPO/topical AB
Alt (females): Hormonal tx + topical retinoid +or- BPO
or BPO/Topical AB
Maintenance therapy for acne
Topical retinoid ± BPO or BPO/topical AB
What organism is implicated in Acne Vulgaris?
- Propionibacterium acnes
What organism is implicated in erythrasma?
-Corynebacterium minutissimum
Appearance of erthrasma
well defined scaly red, pink or brown patches in intertigous areas.
Predisposing factor to erythrasma
-Obesity
-Hyperhidrosis
- DM
- tropical climates
Diagnosis of erythrasma
- Clinical
- wood lamp (grows bright pink) to confrm diagnosis
Treatment of erythrasma
- Local antibiotics (clarithromycin/erythromycin)
- Oral antibiotics (clindamycin/erythromycin)
Clostridial myonecrosis (gas gangrene) diagnosis
- Mainly clinical (gas in soft tissues by palpation)
-culture and radiography supports diagnosis.
Management of Gas gangrene
Surgical debridement + Benzylpenicillin
58 year old woman with multiple hyper-pigmented lesions on the inner lower lip and buccal mucosa. family history of metastatic gastric cancer and metastatic colon cancer in mother and her brother respectively. Most likely diagnosis?
Peutz-Jeghers syndrome
Key features of Peutz-Jeghers syndrome
- Muco-cutaneous hyper-pigmented macules in association with hamartomatous polyps
in the GI tract. - Prone to developing cancers, GI bleeding,
& intestinal obstruction
Cause of peutz-jeghers
- Can arise denovo or Autosomal dominantly inherited
- Usually due to deletion of Serine threonine kinase 11 (STK11) gene on chromosome 19.
What are close differentials of Peutz-Jeghers Syndrome?
- Oral naevi & melanotic
(melanocytic) macule - Oral melanoacanthoma
- Smoker’s melanosis
- Addison disease
Investigations in Peutz-Jeghers Syndrome
1st line: FBC
2nd line (if low MCV) ;
iron studies, FOBT
- genetic testing may be offered (MLPA)
Etiology of Acute paronychia
Bacterial (often S. aureus) secondary to injury.
Presentation of Acute paronychia
Solitary painful distal finger + or - Pus
Management of Acute Paronychia
Antibiotics + or - I & D (if pus collection).
Etiology of Chronic Paronychia
Candida Yeast infection
Clinical presentation of Chronic Paronychia
. Painless nail fold swelling with loss of cuticle.
- Ridging & discoloration may occur
Management of Chronic Paronychia
- keep the skin dry
- Avoid manicures
- Topical imidazole
Treatment of choice for onychomycosis
-Oral Terbinafine
alternatives = flucocanzole & itraconazole
Typical presentation of Pyoderma gangrenosum
Inflammatory papule or pustule that progresses to a painful ulcer with violaceous undermined border.
Etiology of pyoderma gangrenosum
immune dysregulation plays a role
