Dermatology Flashcards

1
Q

What is acne vulgaris?

A

Affects face, neck & upper trunk

There’s obstruction of the pilosebaceous follicle with keratin plugs, which results in comedones, inflammation & pustules.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Who gets acne vulgaris?

A

80-90% of teenagers, 60% seek medical advice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What bacteria is present in acne vulgaris?

A

Propionibacterium acnes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Pathology of acne vulgaris

A

Ance is a disorder of the pilosebaceous unit (hair follicle + sebaceous gland)

There’s increased sebum production (due to androgenic hormones), bacterial colonisation (P. acnes) and inflammatory mediators

Development of acne is multifactorial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Risk factors for acne vulgaris

A
Puberty
PCOS
Congenital adrenal hyperplasia 
Exogenous steroids/testosterone
Medications - steroids, anti epileptics, EGFR inhibitors 
High glycemic index foods
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Symptoms of acne vulgaris

A

Comedones - dilated sebaceous follicle. If the top is closed = whitehead, if the top is open = blackhead

Inflammatory lesions when the follicle bursts = papules and pustules

an excessive inflammatory response = nodules and cysts

Scarring - ice pick scars and hypertrophic scars

Drug induced acne - monomorphic e.g. pustules in steroid use

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is a papule?

A

a solid or cystic raised spot on the skin that is less than 1cm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is a pustule?

A

small inflamed pus filled blister like sore on the skin surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is acne fulminans?

A

very severe acne associated with systemic upset (fever). Hospital admission is often required and the condition usually responds to oral steroids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How can acne be classified?

A

mild: open and closed comedones with or without sparse inflammatory lesions

moderate acne: widespread non-inflammatory lesions and numerous papules and pustules

severe acne: extensive inflammatory lesions, which may include nodules, pitting, and scarring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the mx for acne vulgaris?

A

1st = single topical retinoid or benzoyl peroxide

2nd = topical combination therapy with topical abx, benzoyl peroxide or topical retinoid

3rd = oral abx (tetracyclines = lymecycline, oxytetracycline or doxycycline) OR COPC in women + co-prescribe topical retinid/benzoyl peroxide (but not a topical abx)

4th = oral isotretinoin under specialist supervision

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What tx for acne can you not give to pregnant women?

A

Retinoids

Tetracyclines - lymecycline, oxytetracycline or doxycycline. Use erythromycin instead

Oral isotretinoin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the complications of acne?

A

Post inflammatory lesions - scarring and hyperpigmentation

Mental health impact

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are some prognostic markers associated with severe eczema?

A
onset at age 3-6 months
severe disease in childhood
associated asthma or hay fever
small family size
high IgE serum levels
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the Mx for eczema?

A
  1. emollients (E45, diprobase, oilatum, aveeno), soap substitutes
  2. topical steroids - hydrocortisone, eumovate, betnovate, dermovate
  3. UV radiation
  4. immunosuppressants: e.g. ciclosporin, antihistamines and azathioprine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is eczema?

A

chronic atopic condition caused by defects in the normal continuity of the skin barrier, leading to inflammation in the skin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Symptoms of eczema

A

Dry, red, itchy and sore patches on the skin
On flexor surfaces - inside the elbows and knees & face/neck
Have flares

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Side effects of topical steroids

A

thinning of the skin = skin is more prone to flares, bruising, tearing, stretch marks and telangiectasia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What bacteria opportunistically infect the skin of patients with eczema?

A

Staph aureus (tx flucloaxacillin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is eczema herpeticum?

A

a viral skin infection in patients with eczema caused by the herpes simplex virus (HSV) or varicella zoster virus (VZV).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is basal cell carcinoma?

A

One of the 3 main types of skin cancer
Lesions are slow growing and only locally invade, metastases are extremely rare

Lesions are called rodent ulcers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Symptoms of basal cell carcinoma

A

Sun exposed sites are affected - head & neck, not the ear

Initially are pearly flesh coloured papules with telangiectasia

They then may ulcerate, leaving a central crater

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How should patients with suspected BCC be referred?

A

Routine referral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Mx of BCC

A
surgical removal
curettage
cryotherapy
topical cream: imiquimod, fluorouracil
radiotherapy

Do a punch biopsy if treatment other than standard surgical excision is planned

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the subtypes of BCC?

A

Nodular
Morphoeic
Superficial
Pigmented

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is cellulitis?

A

an inflammation of the skin and subcutaneous tissues, typically due to infection by Streptococcus pyogenes or Staphylcoccus aureus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What bacteria commonly cause cellulitis?

A

Strep pyogenes

Staph aureus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the symptoms of cellulitis?

A

Commonly occurs on the shins
Erythema, pain and swelling
systemic upset - fever

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Ix for cellulitis

A

Clinical diagnosis

Can do bloods and blood cultures if sepsis is suspected

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How can cellulitis be classified?

A

With Iron classification

I = no signs of systemic toxicity

II = systemically unwell / co-morbidity which may complicate or delay resolution

III = significant systemic upset (acute confusion, tachycardia, tachypnoea, hypotension) / unstable co-morbidity (vascular compromise of limb)

IV = sepsis syndrome or severe life threatening infection e.g. necrotising fasciitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Who should be admitted for IV antibiotics with cellulitis?

A

Eron classification III or IV cellulitis
Severe/rapidly deteriorating cellulitis
<1yo / frail
Immunocompromised
Significant lymphoedema
Facial cellulitis or periorbital cellulitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Mx of cellulitis

A

1) oral abx if Eron classification I or II: flucloxaccilin, clarithromycin, erythromycin (pregnancy) or doxycycline
2) IV abx in Eron classification III or IV: co-amoxiclav, cefuroxime, clindamycin or ceftriaxone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What are the 2 types of contact dermatitis?

A

Irritant contact dermatitis

Allergic contact dermatitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is irritant contact dermatitis?

A

common - non-allergic reaction due to weak acids or alkalis (e.g. detergents).
Often seen on the hands.

Erythema is typical, crusting and vesicles are rare

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is allergic contact dermatitis?

A

type IV hypersensitivity reaction.

Uncommon - often seen on the head following hair dyes.

Presents as an acute weeping eczema which predominately affects the margins of the hairline rather than the hairy scalp itself.

Topical treatment with a potent steroid is indicated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is pityriasis versicolor?

A

Also called tinea versicolor

Is a superficial cutaneous fingal infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is the fungus that causes pityriasis versicolor?

A

Malassezia furfur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Symptoms of pityriasis versicolor

A
Most commonly affects trunk 
Patches are hypo pigmented, pink or brown 
More noticeable following a suntan 
Scale is common
Mild pruritus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Risk factors for pityriasis versicolor

A

can occur in healthy individuals
Immunosuppression
Malnutrition
Cushings syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Mx of pityriasis versicolor?

A

Topical anti fungal - ketoconazole shampoo

If it doesn’t respond - consider another diagnosis (send scrapings to confirm diagnosis) + oral itraconazole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is the cause of cutaneous warts?

A

HPV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Symptoms of cutaneous warts

A

Commonly seen on hands and feet (verruca = plantar wart)

Firm raised, with a rough surface that resembles a cauliflower

43
Q

Symptoms of lichen planus

A

itchy, papular rash most common on the palms, soles, genitalia and flexor surfaces of arms
rash often polygonal in shape, with a ‘white-lines’ pattern on the surface (Wickham’s striae)
Koebner phenomenon may be seen (new skin lesions appearing at the site of trauma)
oral involvement in around 50% of patients: typically a white-lace pattern on the buccal mucosa
nails: thinning of nail plate, longitudinal ridging

44
Q

Mx of lichen planus

A

Topical potent steroids

Benzydamina mouthwash or spray

May need oral steroids or immunosuppression

45
Q

Mx for cutaneous warts

A

Topical salicylic acid

Cryotherapy

46
Q

Referral to dermatology for cutaneous warts if..

A

An uncertain diagnosis.
A facial wart.
Multiple recalcitrant warts and compromised immunity.
Extensive warts.
Persistent warts that are unresponsive to available primary care treatments.

47
Q

What is folliculitis?

A

Localised inflammation of the hair follicle or sebaceous gland that is limited to the epidermis

48
Q

What is hot tub folliculitis?

A

Pseudomonal folliculitis that appears 8-48 hours after exposure to contaminated water, is usually self limiting and doesn’t require abx

49
Q

Symptoms of folliculitis

A

tender papules / pustules
Pruritic
Located at the site of hair follicles

50
Q

What causes head lice?

A

the parasitic insect Pediculus capitis

51
Q

What is the life cycle of head lice?

A

Head lice - only live on humans and feed on blood

Eggs - grey/brown, glued to hair close to snap. Hatch in 7-10 days

Nits - empty egg shells, white, shiny. found further along the hair shaft as they grow out

52
Q

Symptoms of head lice

A

New cases have no symptoms

Itching occurs 2-3 weeks after infection

53
Q

Diagnosis of head lice

A

fine-toothed combing of wet or dry hair

54
Q

Mx of head lice

A

treatment is only indicated if living lice are found

a choice of treatments should be offered - malathion, wet combing, dimeticone, isopropyl myristate and cyclomethicone

household contacts of patients with head lice do not need to be treated unless they are also affected

No school exclusion advised

55
Q

What is impetigo?

A

a superficial bacterial skin infection usually caused by either Staphylcoccus aureus or Streptococcus pyogenes.

56
Q

symptoms of impetigo

A

‘golden’, crusted skin lesions typically found around the mouth

Tends to occur on the face, flexures and limbs not covered by clothing

very contagious

57
Q

How is impetigo spread?

A

Direct contact with discharges from the scabs of an infected person

Indirect spread via toys, clothing, equipment and the environment can occur

58
Q

what is the incubation period for impetigo?

A

4-10 days

59
Q

Mx of impetigo

A

1) hydrogen peroxide 1% cream
2) topical abx creams: topical fusidic acid, topical mupirocin
3) oral flucloxacillin or erythromycin

60
Q

Should children with impetigo be kept off school?

A

children should be excluded from school until the lesions are crusted and healed or 48 hours after commencing antibiotic treatment

61
Q

What is malignant melanoma?

A

A malignant tumour arising from melanocytes in the skin

62
Q

Risk factors for malignant melanoma

A
A personal/family hx of skin cancer
Pale skin 
Hx of sunburn 
Hx of sun bed use 
Large number of moles
Increasing age
Organ transplant recipients
63
Q

symptoms of malignant melanoma

A

Major features (2 points each):

  • Change in size
  • Irregular shape or border
  • Irregular colour

Minor features (1 point each):

  • Largest diameter 7mm or more
  • Inflammation
  • Oozing or crusting of the lesion
  • Change in sensation (including itch)

Suspicion is greater for lesions scoring 3 points or more

64
Q

Ix for malignant melanoma

A

Excision biopsy & histology

65
Q

What are the types of malignant melanoma

A

Superficial spreading (most common type) - get on the arms, legs, back and chest in young people. Is a growing mole.

Nodular melanoma (second most common and most aggressive form) - sun exposed skin on middle aged people. Red or black lump or lump that bleeds/oozes

Lentigo melanoma - chronically sun exposed skin, older people. A growing mole

Acral lentiginous - a rare form. Nails, palms or soles. In African Americans or asians. Subungal pigmentation (Hutchinson’s sign) or on palms/feet

66
Q

mx of malignant melanoma

A

Suspicious lesions = excision biopsy to completely remove lesion, histology
Once diagnosis is confirmed on histology, a report will say whether further re-exision of margins is required
Sentinel lymph node mapping
Isolated limb perfusion
Block dissection of regional lymph node groups

67
Q

What predicts the prognosis of malignant melanoma?

A

Dependent on the stage which is assessed by the thickness, level of ulceration and spread to local lymph nodes

68
Q

What predicts the prognosis of malignant melanoma?

A

Dependent on the stage which is assessed by the thickness (Breslow depth), level of ulceration and spread to local lymph nodes

69
Q

What is erythema nodosum?

A

Inflammation of subcutaneous fat that causes tender, red, nodular lesions. Usually over the shins, forearms or thighs.

Resolves within 6 weeks, lesions heal without scarring.

70
Q

Causes of erythema nodosum

A

infection -
streptococci
tuberculosis
brucellosis

systemic disease -
sarcoidosis
inflammatory bowel disease
Behcet’s

malignancy/lymphoma

drugs -
penicillins
sulphonamides
COPC

71
Q

Causes of erythema nodosum

A

infection -
streptococci
tuberculosis
brucellosis

systemic disease -
sarcoidosis
inflammatory bowel disease
Behcet’s

malignancy/lymphoma

drugs -
penicillins
sulphonamides
COPC

Pregnancy

72
Q

Mx of guttate psoriasis

A

Most cases resolve in 2-3 months without tx

Can use topical agents as per psoriasis
UBV phototherapy
tonsillectomy in recurrent cases

73
Q

What is pyoderma gangrenosum?

A

Rare non infectious inflammatory disorder. Uncommon cause of very painful skin ulceration. Affects lower legs most commonly.

74
Q

Causes of pyoderma gangrenosum

A

idiopathic in 50%

inflammatory bowel disease in 10-15% -
ulcerative colitis
Crohn’s

rheumatological -
rheumatoid arthritis
SLE

haematological -
myeloproliferative disorders
lymphoma
myeloid leukaemias
monoclonal gammopathy (IgA)

granulomatosis with polyangiitis

primary biliary cirrhosis

75
Q

Symptoms of pyoderma gangrenosum

A

location:

  • typically lower limb
  • soften at the site of a minor injury

initially features:

  • starts quite suddenly
  • small pustule, red bump or blood-blister

later features:

  • skin breaks down resulting in an ulcer which is often painful
  • edge of the ulcer = purple, violaceous and undermined.
  • the ulcer itself may be deep and necrotic

may be accompanied by systemic symptoms:

  • fever
  • myalgia
76
Q

Mx of pyoderma gangrenosum

A

Oral steroids

Immunosuppression - ciclosporin / infliximab

77
Q

What is psoriasis?

A

a common chronic skin disorder

Red scaly patches on the skin

78
Q

causes of psoriasis

A

genetic: associated HLA-B13, -B17, and -Cw6.

immunological factors

environmental: it is recognised that psoriasis may be worsened (e.g. Skin trauma, stress), triggered (e.g. Streptococcal infection) or improved (e.g. Sunlight) by environmental factors

79
Q

complications of psoriasis

A

psoriatic arthropathy (around 10%)
increased incidence of metabolic syndrome
increased incidence of cardiovascular disease
increased incidence of venous thromboembolism
psychological distress

80
Q

symptoms of psoriasis

A

red, scaly patches on the skin
nail signs: pitting, onycholysis
arthritis

81
Q

mx of psoriasis

A

regular emollients may help to reduce scale loss and reduce pruritus

first-line: NICE recommend:
a potent corticosteroid (betamethasone) applied once daily plus vitamin D analogue applied once daily (topical calcipotriol)
should be applied separately, one in the morning and the other in the evening)
for up to 4 weeks as initial treatment

second-line: if no improvement after 8 weeks then offer:
a vitamin D analogue twice daily

third-line: if no improvement after 8-12 weeks then offer either:
a potent corticosteroid applied twice daily for up to 4 weeks, or
a coal tar preparation applied once or twice daily
short-acting dithranol can also be used

82
Q

secondary care mx for psoriasis

A

Phototherapy with UVB

Oral methotrexate / ciclosporin / oral isotretinoin / infliximab

83
Q

what is squamous cell carcinoma?

A

a common variant of skin cancer. Metastases are rare but may occur in 2-5% of patients.

84
Q

risk factors for SSC?

A

excessive exposure to sunlight / psoralen UVA therapy
actinic keratoses and Bowen’s disease
immunosuppression e.g. following renal transplant, HIV
smoking
long-standing leg ulcers (Marjolin’s ulcer)
genetic conditions e.g. xeroderma pigmentosum, oculocutaneous albinism

85
Q

tx of ssc?

A

Surgical excision with 4mm margins if lesion <20mm in diameter.
If tumour >20mm then margins should be 6mm.
Mohs micrographic surgery may be used in high-risk patients and in cosmetically important sites.

86
Q

Histology of psoriasis

A

On histology, there is epidermal hyperplasia (acanthosis), hyperkeratosis with retention of nuclei in stratum corneum (parakeratosis) and groups of neutrophils in the stratum corneum (Munro microabscesses).

87
Q

what is a mole?

A

a benign neoplasm of melanocytes

also called nevus

88
Q

What are the 6 Ps of lichen planus?

A

Pruritic, purple, polygonal, planar papules and plaques

89
Q

What is the mx for scalp psoriasis?

A

Potent topical corticosteroid for 4 weeks OD

If unsuccessful:

  • Different formulation of potent corticosteroid e.g. shampoo/mouse
  • Or topical agents to remove scale e.g. salicylic acid, emollients or oils before applying the steroid
90
Q

warnings with topical steroids

A

may lead to skin atrophy, striae and rebound symptoms

the scalp, face and flexures are particularly prone to steroid atrophy so topical steroids should not be used for more than 1-2 weeks/month

systemic side-effects may be seen when potent corticosteroids are used on large areas e.g. > 10% of the body surface area

NICE recommend that we aim for a 4-week break before starting another course of topical corticosteroids

they also recommend using potent corticosteroids for no longer than 8 weeks at a time and very potent corticosteroids for no longer than 4 weeks at a time

91
Q

Example vitamin D analogue

A

Calcipotriol

92
Q

Can vitamin D analogues be used long term

A

YEs, unlike steroids

93
Q

Can vitamin D analogues be used in pregnancy?

A

No, this should be avoided

94
Q

What are the nail changes seen in psoriasis?

A

pitting
onycholysis (separation of the nail from the nail bed)
subungual hyperkeratosis
loss of the nail

95
Q

What causes scabies?

A

the mite Sarcoptes scabiei

96
Q

How is scabies spread?

A

By prolonged skin contact

97
Q

Pathology of scabies infection

A

The scabies mite burrows into the skin, laying its eggs in the stratum corneum.

The intense pruritus associated with scabies is due to a delayed-type IV hypersensitivity reaction to mites/eggs which occurs about 30 days after the initial infection.

98
Q

Symptoms of scabies

A

widespread pruritus

linear burrows on the side of fingers, interdigital webs and flexor aspects of the wrist

in infants, the face and scalp may also be affected

secondary features are seen due to scratching: excoriation, infection

99
Q

Mx of scabies

A

permethrin 5% is first-line

malathion 0.5% is second-line

give appropriate guidance on use - apply it to cool, dry skin. Apply all over including the face and scalp. Pay close attention to areas between fingers/toes, under nails, armpit areas. Leave to dry for 8-12 hours (permethrin) or 24 hours (malathion) before washing off. Repeat 7 days later

pruritus persists for up to 4-6 weeks post eradication

Avoid close physical contact until treatment is complete

All household and close physical contacts should be treated at the same time, even if asymptomatic

Lander, iron or tumble dry clothing, bedding and towels

100
Q

what is Stevens-johnson syndrome?

A

a severe systemic reaction affecting the skin and mucosa that is almost always caused by a drug reaction.

101
Q

Symptoms of Stevens-johnson syndrome

A

rash is typically maculopapular with target lesions being characteristic. May develop into vesicles or bullae

mucosal involvement

systemic symptoms: fever, arthralgia

102
Q

Causes of Stevens-johnson syndrome

A
penicillin
sulphonamides
lamotrigine, carbamazepine, phenytoin
allopurinol
NSAIDs
COCP
103
Q

Mx of Stevens-johnson syndrome

A

hospital admission is required for supportive treatment

104
Q

risk factors for Stevens-johnson syndrome

A

female
HIV
Mycoplasma / CMV