Dermatology - Eczema, Psoriasis and Infection Flashcards
(365 cards)
1
Q
Main features of eczema
A
Red, itchy, dry
2
Q
Physical signs in eczema
A
Erythema Scale Excoriation Exudate Crusting Hyperkeratosis Lichenificaation
3
Q
Excoriation
A
Scratch marks
4
Q
Hyperkeratosis
A
Excessive production of epidermis which stays stuck and becomes thick (like on feet)
5
Q
Lichenification
A
Increased roughened skin markings due to rubbing
6
Q
Vesicles
A
Raised, clear fluid-filled lesion <0.5cm in diameter
7
Q
Sub erythroderma vs erythroderma eczema
A
Sub erythroderma (70-90%) Erythroderma (>90%)
8
Q
Exudate
A
Fluid oozing which dries to form crust
9
Q
Who can atopic eczema affect
A
Adults or children
10
Q
What are included in atopic disease
A
Eczema
Asthma
Urticaria
Hay fever
11
Q
What gene abnormality is accosted w/ atopic eczema
A
Fillagrin gene abnormalities
Cross hatching in thenar eminence
12
Q
How does atopic disease manifest in skin
A
Disruption in barrier function of skin - makes skin ‘leaky’
13
Q
Typical sites of atopic eczema
A
Flexures
14
Q
Different strengths of corticosteroids
A
Mild (e.g. 1% hydrocortisone) x4 - face
Medium (e.g. eumovate) x4 - flexures
Potent (e.g. betnovate) x4 - limbs
Very potent (e.g. dermovate) - thicker skin e.g. palms and soles
15
Q
Difference in strength from mild and very potent steroids
A
64x
16
Q
Are cushingoid features common w/ topical steroids
A
No
17
Q
Asteatotic eczema
A
Cuased by lack of oil
Usually seen in older people nursing homes or long stay hosp pts
18
Q
How much does oil production change per year
A
1% drop with age
19
Q
Treatment of asteatotic asthma
A
Bathes less often, short and cooler
Use less detergent
Apply oil to skin or emollients
Keep air moist in home
20
Q
Irritant contact eczema
A
Chemicals will irritate skin cells deepening on exposure and conc
Irritation isn’t same as allergy (due to immune process)
21
Q
What can irritant contact eczema present as
A
Looks same as atopic eczema - hx is imperative
22
Q
Allergic contact eczema
A
Comes on a few hrs to 96 hrs after contact
Investigate w/ patch tests
23
Q
Common skin allergens
A
Nickel
Fragance
Chromate
Formaldehyde
24
Q
Ix for allergic contact dermatitis
A
Patch tests
Apply patches day 1
Remove day 3
Read days 3 and 5 - redness, itch, scale
Select batteries according to hx and distribution
25
Why is diagnosing varicose eczema important
Commonly breaks down (infection or scratching) to form leg ulcer
26
Treatment of venous stasis
```
Lose wt
Exercise
Elevate legs
Avoid standing/ sitting for long periods
Compression bandages
VV surgery
```
27
Eczema and scratching
Scratching causes lichenification long term
Excoriated skin exudes and crust
May become secondarily infected
28
What type of lichenification can be caused by scratching
Lichen simplex
29
Why are bandages used in eczema
Stops scratching and break scratch/ itch cycles
| Paste bandages of wet wraps can be used in children
30
When should bandages not be used for eczema
If eczema is infected
31
Infected eczema (bacterial)
Often due to scratching and causes impetiginous change
Commonly due to presence of Staph A
Produces impetiginized eczema
32
Impetiginized eczema
Produces yellow (aureus) crust and/ or blisters of impetigo
33
Infected eczema (viral)
Herpes simples - causes cold sores
Also infects eczema on head and neck
Eczema herpeticum
34
Eczema herpeticum
Erythematous, vesicular, well defined crusted blisters
35
Discoid
Coin shaped
36
Discoid eczema
Variant of bacterial infected eczema
37
What is discoid eczema often confused with
Psoriasis
| But has follicular areas, less well defined and lacks psoriasis scale usually
38
What does discoid eczema often co-exist with
W/ areas of follicular eczema
39
Treatment for discoid eczema
Abx and antiseptic/ steroid combi needed
40
Pompholyx eczema
Little blisters down the sides of fingers
Intensely itchy
Episodic
41
Causes of pompholyx eczema
Allergy or endogenous (atopic) or both
42
What is seborrhoeic eczema sue to
Sensitivity to yeast on skin
| Not due to yeast in diet
43
Epidemiology of seborrhaeic eczema
Very common (esp in older pts)
44
What can negatively affect sebborhoeic
Made worse by stress
| Severe in HIV disease
45
What does seborrhoeic eczema rash
Dandruff
| Rash on eyebrows, nose, nasolabial folds and flexures
46
Treatment of seborrhoeic eczema
Treat w/ topical or systemic antifungals +/- corticosteroid creams
47
General treatment of eczema
```
Emollients if dry
Antiseptic soaks if oozing
Topical steroids depending on degree of infl
Abx course if infected or discoid
Antifungals if seborrheic
Antivirals if herpes
Bandaging if scratching
Elevation etc in stasis
```
48
More aggressive treatments for eczema
PUVA
Oral alitretinoin
Oral azathioprine, ciclosporin - broad spectrum immunosuppressants
49
Ddx of eczema
```
Scabies
Fungal infection in hands
Psoriasis
Drug eruption
Rarer diseases e.g. bullous pemphigoid, dermatitis herpetiformis, mycosis fungoides
```
50
Scabies as ddx of eczema
Burrows between the fingers and friends/ family usually affected
51
Fungal infection in hands as ddx of eczema
Often unilateral (one hand, tow feet)
52
Psoriasis as ddx of eczema
Can be itchy but different Physical signs
53
Tineal (fungal) hand infection
Fine, silver scale in creases, lack of cracking and often unilateral
Take fungal scrapings if unsure
54
Psoriasis and discoid eczema
Similar, nail changes can occur in both
| But different physical signs, look at scalp
55
Skin functions
```
Protective barrier
Temperature regualtion
Sensation
Immunosurveillance
Appearances/ cosmesis
Waterproofing
```
56
Cell types in epidermis
Keratinocytes
Langerhans' cells
Melanocytes
Merkel cells
57
Keratinocytes function
Protective barrier
58
Langerhan's cell function
Present antigens and activate T-lymphocytes for immune protection
59
Melanocytes function
Produce melanin, which gives pigment to the skin and protects the cell nuclei from UV radiation-induced DNA damage
60
Merkel cells
Contain specialised nerve endings for sensation
61
How many layers does the epidermis have
4, each representing a different stage of maturation of the keratinocytes
62
Epidermal layers
```
Stratum basale (basal cell)
Stratum spinosum (pickle cell layer)
Stratum granulosa (granular cell layer)
Stratum lucidem - found in thicker skin
Stratum corneum (horny layer)
```
Come Let's Get Sun Burnt
63
Stratum basale
Actively dividing cells
| Deepest layer of epidermis
64
What is found in the stratum spinosum
Differentiating cells
| Cells are bound together by desmosomes
65
Function of stratum granulosum
Secrete lipids in extracellular areas
66
Stratum corneum
Layer of keratin
| Most superficial layer of epidermis
67
Lichen planus
C/c autoimmune disorder affecting skin (esp flexor surfaces), mucosa and genitals
Scaliness and itchy skin may be seen
68
A/c px of lichen planus
Affects flexor surfaces
Itchy and can be painful
Distinct, often round, purpuric, raised lesion
69
Healing of lichen planus lesions
Aa the initial lesions heal, leave a small, flat brown discoloured circle
70
Mx of lichen planus
Many cases resolve spontaneously within a yr, can give topical steroids
71
Epidemiology of granuloma annular
Relatively common disorder
| Affects children and young adults
72
Granuloma annulare px
Localised ring of beaded papules on the extremities
73
Mx of granuloma annulare
Many cases resolve spontaneously within a year
74
What does the efficacy of a topical drug depends on
Its internet potency and its ability to penetrate skin
75
Factors affecting penetration of topical drugs
Conc of medication
Thickness and integrity of stratum corneum
Frequency of application
Compliance
76
Factors affecting pharmcokinetics of topical drugs
Anatomy/ site
hydration of skin
Type of compound - hydrophilic vs phobic
Age
77
Common drugs given for derm
```
Steroids
Retinoids
Calcineurin inhibitors
Topical abx
Imiquimod
Sunscreens
```
78
Why are steroids given in derm
Effective at reducing symptoms tops of infl, but dint address underlying cause of disease
79
Which dermatoses are most responsive of steroids
Psoriasis
| Atopic dermatitis
80
Topical calcineurin inhibitors
NSAIDs that reduce pro-infl cytokines responsive for itch and rash of atopic dermatitis
81
Imiquimod
Topical immunotherapy (enhances cell-mediated immune response)
82
Indications of imiquimod
Genital warts
Superficial BCC
Actinic keratosis
83
Clinically important immune deficiency as a rare cause of skin disease
Infections in HIV (cold sore, thrush)
Skin cancer sin organ transplant recipient
Congenital deficiencies e.g. Wiskott-Aldrich syndrome
84
Allergy vs autoimmunity
Both are examples of overactivity/ abnormal regulation of immune system
Allergy - bad clinical reaction to immune system to environmental antigens (allergens)
Autoimmunity - bad clinical reaction by the immune system to self-antigens (auto antigens)
85
Basis of hypersensitivity reaction in skin
Immunological reactions cause disease by promoting infl
Infl leads to diff clinical patterns of disease
A pattern of disease may be caused by more than one type of immunological reaction
86
What is urticaria characterised by
Short-lived swellings caused by plasma leakage from capillary blood vessels in and below skin
87
Main mediator for plasma leakage in urticaria
Histamine - Type I HS or Type V (in response to autoantibodies)
88
What is histamine released from in Type I HS reaction
```
Most cells (along w/ other mediators)
Degranulation of mast cells may be triggered by allergens or autoantibodies
```
89
Bullous pemphigoid
Acquired blistering condn of the skin, sometimes mucous membranes
90
What type of HS is bullies pemphigoid
II
| Autoantibodies against one or more antigens in the hemidesmosomes
91
Viral skin infections
Herpes simple
Herpes zoster or shingles
Viral warts
Molluscum contagiosum
92
Pathogen causing Herpes simplex
HSV-1 or HSV-2
93
Features of cold sores
Painful (neuropathic - tingling), self-limited
| Often seen in recurrent dermatoses
94
Prevalence of HSV1 and HSV2
HSVI - orofacial (80-90%), sometimes genital
| HSV2 - genital (70-90%), sometimes orofacial
95
Transmission of HSV
Direct contact at a mucosal surface or on site of abraded skin
96
Symptoms and signs of herpes simplex
Painful (sore) grouped vesicles on erythematous base --> crust + erosions
97
Dx of HSV
Usually clinical
Direct microscopy (Tznack smear)
Viral culture
98
Treatment of genital herpes simplex
Topical acyclovir 5% ointment
SystemicL: aciclovir - 200mg 5x/day for 5/7
Prophylaxis: 200mg TDS for 6/12 - 12/12
99
Alternative treatments of HSV
Famciclovir
| Valacyclovir
100
HSV in immunocomoproimised
Lesions can be extensive or c/c
101
Prognosis of HSV
HSV persists in Doral root ganglia for life so tends to reoccur
102
Compliactions of HSV
Erythema multiform
Eczema herpeticum
Affects CNS
103
Definition of herpes zoster
A/c painful dermatomal dermatoses
104
Prevalence of herpes zoster
10-20% of adults have hx of disease
105
Transmission of herpes zoster
Reactivation of latent VZV in a sensory ganglion (previously had chicken pox)
106
Symptoms and signs of shingles
Pain in a demrtaomal or band like pattern
| Followed by group of grouped vesicles on erythematous base --> crusting, fever and malaise
107
Dx of shingles
Viral culture
Tzanck smear
DDFA
Serology
108
Treatment of shingles
Analgesics
| Aciclovir (effective 24-72hr of disease onset) 800mg 5x/day for 5/7
109
Prognosis of shingles
Symtoms resolve in 2-3/ 52
110
Complications of shingles
Post-herpetic neuralgia
Cranial nerce syndromes e.g. Ramsey hunt syndrome
In immunocompromised: disseminated form
111
Pathogen causing viral warts
HPV
112
Viral wart definition
Benign epithelial growth (premalignant on genitals and immunosuppressed - 16-18 subtypes )
113
Prevalence of viral warts
5% of population
114
Transmission of viral warts
Skin to skin contact
| Sexually (condyloma acuminatum)
115
Symptoms of viral warts
Hyperkeratotic, flesh-coloured papule and/or plaque studded w/ small dots (thromboses capillaries)
116
Dx of viral warts
Clinical appearance
| Histology if any doubt
117
Treatment of viral warts
No treatment
Topical salicylic acid
Cryosurgery
118
Prognosis of viral warts
Remove spontaneously within yrs
| In immunocompromised; warts are resistant
119
Complications of viral warts
SCC genitals e.g. 16-18 subtypes
120
Pathogen causing molluscs contagious
Molluscum contagious virus (MCV) (poxvirus)
121
Definition of molluscum contagiousm
Benign self-limited papular eruption
122
Prevalence of molluscum contagiousum
Common in children and sexually active adults
123
Transmission in mollucsum contagiosum
Skin to skin contact
124
Symptoms in mollucscum contagiousm
Smooth flesh-coloured, dome-shaped, umbilicate papules contain keratotic (cheesy) plug
125
Dx of MCV
Clinical appearance
126
Prognosis of MCV
Spontaneous resolution
127
Treatment of MCV
May not be necessary
Cryotherpay
Curettage
May use topical immunomodulator drugs
128
Bacterial skin infections
```
Impetigo
Folliculitis, furunculosis, carbunculosis
Ecthyma
Erysipelas and cellulitis
Necrotizing fasciitis
```
129
Pathogen causing impetigo
Staph A > Strep pyogenes
130
Impetigo
Superficial skin infection
131
Prevalence of impetigo
1%
132
Transmission of impetigo
S. aureus and S. pyogenes are infrequent resident flora of skin
133
Symptoms of non-bullous impetigo
Vesicles or pustules or erythemautos skin --> erosions --> golden-yellow crust
134
Symptoms of bullous impetigo
Flaccid bullae w/ clear, yellow fluid (S. aureus) --> erosions ---> golden-yellow crust
135
Dx of bullous impetigo
Clinical px
| Confirmation by culture
136
Treatment of bullous impetigo
Topical aciclovir and/ or systemic abx e.g. topical mupirocin TDS for 7-10days or systemic beta lactams
137
Pathogens causing infection of hair follicles
Staph A
Psuedomonas aeruginosa
Folliculitis, furunculosis, carbunculosis
138
Transmission of infection of hair follicles
S. aureus is infrequent resident flora of skin
| Exposure to P. aeruginosa in hot tubs or swimming pools
139
Different infections of fair follicles
Folliculitis - most superficial
Furunculosis
Carbunculsosis - deepest
140
Dx of infection of hair follicles
Clinical px
| Conformation by culture
141
Treatment of infections of hair follicles
Topical treatments w/ 1% clindamycin or 2% erythromycin
| Systemic antistpah abx, incision and drainage
142
Symptoms in folliculitis
Generally asymptomatic
| But may be pruiritis and painful
143
Furunculosis
Tender, erythematous, fluctuant nodules that rupture w/ purulent discharge
144
Carbunculosis
Larger & deeper infl nodules often w/ purulent drainage
145
Ecthyma
Deep infection of the skin (down to epidermis) that causes a shallow, round, punched out ulcer
146
Pathogens causing ecthyma
Staph A
Strep pyogenes
Botha re infrequent resident flora of skin
147
Symptoms of ecthyma
Vesicles and bullae that progress to punched out ulcerations w/ adherent crust, which heals w/ scarring
148
Dx of ecthyma
Clinical px
| Confirmation by culture
149
Treatment of ecthyma
Oral staphylococcal abx
150
Erysipelas and cellulitis
Erysipelas - super infection of skin, involves upper dermis and superficial lymphatics
Cellulitis - Deeper infection of skin, involving deep dermis and s/c tissue
151
Pathogens causing erysipelas;as and cellulitis
Staph A and strep pyogene
152
Symptoms of erysipelas
Tender, well-defined, erythematous patch
153
Symptoms of cellulitis
Ill-defined erythematous and oedematous patch
154
Dx of erysipelas and cellulitis
Clinical px
155
Treatment of erysipelas and cellulitis
Beta lactams - e.g. fluclox/ amoxi or erythromycin
156
Pathogens causing necrotising fasciitis
```
Strep pyogenes
Gp B and C strep
Vibrio vulnifics
Clostridium perfigens
Bacteroides fragilis (mixed infection)
```
157
Necrotizing fasciitis
Life threatening infection of s/c tissue and fascia
158
Causes of necrotising fasciitis
Idiopathic
After surgery/ trauma - cutaneous portal of entry
IVDU
159
Symptoms seen in necrotising fasciitis
Erythema and severe pain extending to deep to underlying fascia
Skin becomes dusky and bullae form
160
Progression of symptoms in necrotising fasciitis
Severe pain, erythema and oedema followed by necrosis, gangrene
Fever, systemic toxicity, organ failure, shock, death
161
Dx of necrotising fasciitis
Bx for histology
| Gram stain and culture for identifying causative pathogen
162
Treatment of necrotising fasciitis
Surgical debridment or amputation
| Abx (gentamicin, clindamycin)
163
Parasitic skin infections
Scabies
Cutaneous and mucocutaneous leishmaniasis
Cutaneous larva migrans
164
Scabies
Infective disease of the skin caused by S. scabiei burrowing into the epidermis
165
Transmission of scabies
Skin to skin contact
166
Symptoms of scabies
Intense itching, esp at night
| Burrows, vesicles, papule and pustules
167
Location of scabies lesions
```
Finger webs
Around wrists Elbows
Armpits
Waist
Thigh
Genitals, nipples, breast and lower buttocks
```
168
Dx of scabies
Looking for mites
| Eggs under microscopes (skin scrapings)
169
Treatment for scabies
Skin lotions contain permethrin
All family members, all over body
Repeat treatment in 7/7
170
Pathogen causing cutaneous and mucocutaneous leishmaniasis
Leishmania tropica (cutaneous)
L. brazilenis (mucocutaneous)
L mexican, L. aethiopia (diffuse cutaneous)
Originate from sand fly
171
Symptoms in cutaneous leishmanias
Skin lesions w/ erythema, infl and ulceration
172
Symptoms in mucocutaneous leishmaniasis
Lesions of mnasal and/ oral mucosa
173
Symptoms of diffuse cutaneous leishmaniasis
Multiple, deep skin lesions
174
Mucocutaneous leishmaniasis
Infections disease of skin caused by Leishmania spp, growing and destroying epidermis and mucosae
175
Transmission of leishmaniasis
Bites of infected sandflies
176
Ddx of leishmaniasis
Appearance of lesions
| Culture of parasite
177
Treatment of leishmaniasis infections
CL: self-healing, abx
| MCL, DCL - pentavalent antimonial , amphotericin B
178
Pathogen causing cutaneous larva migrans
Larvae of dog and cat hookworm
179
Cutaneous larva migrans (creeping eruption)
Cutaneous eruption usually confined onto the skin of the feet, arms, or buttocks caused by migrating larva
180
Transmission of cutaneous larva migrans
Active penetration of the skin by larva
181
Symptoms of cutaneous larva migrans
Erythematous, pruritic, serpiginous lesions that advance severe mm/day
Allergic immune response
182
Dx of cutaneous larva migrans
Classical clinical appearance of the eruption
183
Tx of cutaneous larva migrans
```
Thiabendazole (topical or oral)
Albendazole
Mebendazole
Ivermectin
Abx
```
184
Fungal infections of the ksin
```
Tinea corporis (body)
Tinea capitis (head)
Tinea pedis (feet)
Tinea cruris (groin)
Candida intertrigo
Piyriasis versicolour
```
185
Tinea
Infectious disease of the skin caused by fungi
| Most common organisms are tines verrucosum, Tinea rubrum, micorposrum canis
186
Dx of tinea infections
Skin scrapings by direct microscopy - branching hyphae may be seen
Woods light reveals green flurosence
187
Symptoms of tinea infections
Itch
| Usually peripheral scaling, discoid lesions
188
Tx of tinea infections
Imiadozales (miconozale or clotrimazole) or the allylamines e.g. terbinafine
Systemic antifungals for nails, scalp or widespread, also give. for c/c fungal infections of skin
189
Systemic antifingals for c/c/ infections
Griseofulvin
Terbinafine
Itraconazole
190
Pathogen causing candidal intertrigo
Yeast - candida albicans
191
Candidal intertrigo
Superficial, mycotic infection of skin
| Erythematous, macerated patch w/ satellite macule or pustules extending beyond the flexures
192
Where does candidate interior tend to affect
Tends to affect moist, occluded skin folds
193
Dx of candidate intertrigo
Skin scrapings or swab (black) - culture
194
What should you check if a pt presents w/ widespread candidal intertrigo
DM (fasting glucose, urinalysis)
HIV
These condns make them predisposed to candidiasis
195
Symptoms of candidal intertrigo
Itch, maybe pain
196
Tx for candidal intertrigo
Clotrimazole, terbinafine or antifungals w/ weak steroids e.g. daktacort
Keep area drug - powder anti fungal, loose clothing, wt loss if obese
Severe cases po fluconazole
197
Pathogen causing pityriasis versicolor
Yeast - malassezia furfur
198
Pityriasis veriscolor
Superficial mycotic infections of skin
| Confluent, fine scale, well-dermacted, hypo/hyperpigented plaques
199
Dx of pityriasis verisocolor
Skin scrapings or swab (black)
200
Tx for pityriasis versicolor
Selenium sulphide shampoo (2.5%)
Ketoconazole shampoo
Topical anti fungals
201
Features of c/c plaque psoriasis
Well defined
Erythematous patches
Scaly
Seen in extensor surfaces - elbow, knees, scalp, hands and feet
202
Features of guttate psoriasis
AKA 'rain drop' psoriasis
Common in children
Lesion often erupts after an URTI (strep infetion)
Small scaly plaques
203
What does guttate psoriasis respond well to
Phototherapy
204
Features of pustular psoriasis
Generalised painful erythematous and sterile pustules
A/c px - pyrexia and ill pts
Can be life threatening
205
Complications of pustular psoriasis
2' infection
Disturbed protein and electrolyte imbalance
Renal and liver impairment
206
Types of pustular psoriasis
Generalised pustular psoriasis
Palmoplantar pustolosis
Acrodermatitis continua of Hallopeau
207
Features of palmoplantar pustulosis
Localised to palms and soles
Sterile yellowish and brownish pustules
May have c/c plaque psoriasis elsewhere
208
Features of acrodermatitis continue of Hallopeau
Very rare
Pustules on distal portion of finger and sometimes toes
Shedding of nail can occur if involved
209
Features of flexural psoriasis
Inverse psoriasis
Localised to skin fold (flexures), genitals
Shunt and smooth
Fungal and bacterial trigger may exist
210
Features of scalp psoriasis
Common site in c/c plaque psoriasis
Well defined clay plaques
Can extend from hairline to neck
Hair loss usually transient
211
Features of nail psoriasis
Niall pitting
Onycholysis (loosening of nail)
Subungual hyperkeratosis
212
Types of psoriasis
C/c plaque
Guttate
Pustular
Localised forms
213
Localised forms of psoriasis
Scalp
Nail
Flexural
Oral mucosa
214
Epidemiology of psoriasis
Infl skin disease affecting 2% population
M=F
Two peak: 10-20yrs and 50-60yrs
215
Predisposing factors for psoriasis
```
Genetic
Infection - strep, HIV
Stress
Drugs
Autoimmune - T cell
Trauma - Koebner phenomena
```
216
Drugs predisposing psoriasis
Lithium
BB
Anti-malarial
Tapering down systemic steroids
217
Koebner phenomenon
Formation of new lesions in otherwise healthy skin after cutaneous injury
Lesions are same as preexisting dermatoses
218
Psoriasis as the marker of underlying systemic disease
Psoriasis pts at greater riskier mI, metabolic syndrome
Directly correlates w/ psoriasis severity
Increase mortality in severe psoriasis
219
Metabolic syndrome
Multiplex risk factor that arises from insulin resistance accompanying abnormal adipose deposition and function
220
Topical treatments for psoriasis
```
Vit D3 analogues
Corticosteroids
Dithranol
Retinoids
Coal tar
Salicylic acid
```
221
An example of vit D3 analogue
Calcipotriol
222
MOA of vit D3 analogues
Inhibit epidermal proliferation and infl cell function
223
Indication of vit D3 analogues
Mild to moderate psoriasis
| Some not appropriator face and genitalia
224
Adverse effect of vitamin D3 analogues
Irritation
| Hypercalcaemia
225
Indications for corticosteroids
Mild to moderate psoriasis
226
Adverse effects of corticosteroids for psoriasis
Skin atrophy
Peri-oral dermatitis and steroid rosacea
Allergic contact dermatitis
Suppression of pituitary adrenal axis
Short term use is best
227
Properties of coal tar and wood tars
Anti infl and anti-pruritic
228
Adverse effects of coal tar and wood tars
Unpleasant smell
| Messy formulation - staining
229
Keratolytics for psoriasis
E.g. salicylic acid
Reduces scales --> enhances penetration of topical medications
Risk of systemic intoxication if applied on widespread areas
230
Example of topical retinoid
Tazarotene
231
Topical retinoids for psoriasis
Decrease epidermal proliferation and inhibits differentiation
Not very effective
232
Adverse effects of topical retinoids
Irritation
Pruritus
Burning sensation
Dryness
233
Indications for dithranol
Mild to severe psoriasis
234
Dithranol for psoriasis
Short contact (out-pt)
24 hrs application schedule (in-pt)
Concand application time gradually increased
235
Adverse effects of dithranol
Irritation
| Staining of clothes and skin
236
Phototherpay for psoriasis
Topical PUVA: psoralen baths or topical application
Systemic PUVA: ingestion of psoralen
Narrow band UVB: most optimal option
237
Adverse effects of phototherpay
Skin burn
Increases risk of skin cancer
Cataracts w/ PUVA-ingested
238
MTX indication in psoriasis
Severe psoriasis - reduced lymphocyte proliferation
239
Admin of MTX for psoriasis
Once weekly dose (IM, SC or po)
| Folic acid added on another day
240
Blood monitoring for MTX
FBC
LFTS
U&Es
241
Adverse effects of MTX
```
Nausea
Pancytopenia
Oral erosions
Opportunistic infections
Hepatic and cirrhosis
Interstitial pneumonitis
```
242
Ciclosporin indication for psoriasis
Sever psoriasis - decreases T-cell in epidermis
243
Monitoring for cyclosporin
BP
U&Es
LFTs
Lipids
244
Adverse effects of cyclosporin
```
HTN
Renal failure
Carcinogeneisis
Opportunistic infections
Hyperlipidaemia
```
245
Systemic retinoids
E.g. acitretin
Derived from vit A
Inhibit epidermal proliferation and the activation of polymorphic leukocytes
246
Monitoring of systemic retinoids
LFTs
| Fasting lipids
247
Side effects of systemic retinoids
```
Teratogenic
Dryness of skin and mucosal membranes
Hepatic toxicity
Hyperlipidaemia
Depression and suicidal ideation
```
248
NICE pathway for psoriasis treatment options
1. Topical therapy
2. Phototherapy
3. Specialist referral - for systemic therapy, non-biologics before biologics
249
NICE indications for biological therapy for psoriasis
Moderate to severe plaque psoriasis in adults to fill to repost/ intolerant/ have contraindications to other systemic therapies
250
What is severe psoriasis defined at
PASI > 10
| DLQI > 10
251
Biologics given for psoriasis
```
Adalimumab - anti-TNF
Etanercept - anti-TNF
Ustekinumab - blocks IL-12 7 IL-23
Ixekizumab - blocks IL-17
Secukinumab - blocks IL-17a
```
252
When is infliximab indicated in psoriasis
PASI of 20
| DLQI > 18
253
Adverse effects of biologic therapy in psoriasis
```
Infections (TB) and malignancy
Demylinating disease
Heart failure
Allergic reaction
Lupus-like syndromes
Rarely, sever hepatitis
```
254
PASI
Psoriasis Area Severity Index
Assess severity of psoriasis in 4 body areas
Range from 0 (no disease) to 72 (maximal disease)
Physician-peformed assessment
255
Social effect of psoriasis
Psoriasis affects QoL
Disabling (psoriasi to palms and soles)
Affects social and personal life
Low self esteem
256
DLQI
Dermatology Life Quality Index (DLQI)
A simple, practical pt-focused technique
10 question validated questionnaire
Used to assess impact of skin disease o pt
257
Allergy risk factors
```
First born
Atopic parents (genes)
C-section delivery
Bottle-fed
Early abx
```
258
Types of food hypersensitivity
Food allergy - IgE -mediated food allergy, non-IgE mediated food allergy e.g. coeliac
Non-allergic food HS (formerly food intolerance)
259
What is psoriasis
C/c infl skin condn due to hyperproliferation of keratinocytes and infl cell infiltrations
260
Where does seborrheic psoriasis px
Nasolabial folds
| Retro - auricular
261
Auspitz sign
Seen in psoriasis
| Scratch and gentle removal of scales cause capillary bleeding
262
Complications of psoriasis
Erythroderma
263
Erythema vs purpura
Erythema - redness (due to infl or vasodilation) that DOES blanch w/ pressure
Purpura - red/ purple (bleeding into skin or mucous membrane) that DOES NOT blanch w/ pressure
264
Petechiae
Small pin-point macule
265
Ecchymoses
Larger, flat-like bruises
266
Mx of mild plaque psoriasis
Topical treatments e.g. hydrocortisone, tazarotene
267
Mx of moderate to severe psoriasis
PUVA
MTX
Ciclosporin retinoids
Biologics
268
Mx of gutatte psoriasis
PUVA
Ciclosporin
MTX
269
Mx of pustular psoriasis
Supportive care
PUVA
Systemic agents e.g. cyclosporin, MTX
270
Mx of urticaria
Fexofenadine (antihistamine)
| Sometimes oral steroids are used
271
Macule
Flat area of altered colour
272
Patch
Larger, flat area of altered colour or texture
273
Papule vs nodules
Papule - solid raised lesion <0.5cm in diameter
| Nodule - solid raised lesion >0.5cm in diameter, w/ a deeper component
274
Plaque
Palpable scaling raised lesion >0.5cm in diameter
275
Vesicle vs bulla
Raised clear, fluid-filled lesion <0.5cm (vesicle)/ >0.5 (bulla) in diameter
276
Pustules
Pus-containing lesion <0.5cm in diameter
277
Abcess
Localised accumulation of pus in dermis of s/c tissue
278
Wheal
transient raised lesion due to dermal oedema
279
Excoriation
Loss of epidermis following trauma e.g. scratching
280
How do the different Th cells manifest in disease
Th1 - involve in autoimmune diseases
| Th2 - involved in allergic disease
281
Examples of atopic diseases
```
Asthma
Eczema
Rhinitis
Dermatitis
Food allergy - anaphylaxis, diarrhoea, abdominal pain, FTT
```
282
Conditions and their associated risk of developing asthma
Eczema - 50%
Eczema + allergy - 90%
Rhinitis - 50%
283
Emergency plan for allergens contact
```
Avoidnaces
Antihistamines asap - may need bronchodilator
Repeat histamine
Adrenaline (Epipen or anapen)
Seek medical help
```
284
Systemic signs that might hint at a skin infection
Fever
HR
RR
BP
285
Lab testing for skin infections
```
Swabs
Scrapes
Bx
Aspirates
Bloods - cultures, serology, FBC, CRP
```
286
Toxin mediated skin infections
Staph A - scalded skin syndrome, TSS
| Strep pyogenes - scarlet
287
Tips for describing skin infection lesions
```
Pustules or vesicles
Raised or flat
Crusted or non-crusted
Pus inside dermis or deeper
Ulceration and scarring
Discharge 0 exudate
Progression
Palpation - rough, smooth, indurated
```
288
Production of macule
Local infl
Immune response
Infiltrating leukocytes
289
Production of papule
More marked infl
| Invasion of neighbouring tissues
290
Production of vesicles
Microbe invades epithelium - HSC, VZV
291
Production of ulcer
Epithelium ruptures
| Microbe discharged - HSV, VZV
292
Production of papilloma
Microbe grows in epithelium, which proliferates, microbe shed w/ epithelial cells (warts)
293
Factors affecting microbial load on skin
```
Limited amount of moisture presents
Acid pH of normal skin
Surface temp
Slaty sweat
Exerted chemicals e.g. sebum, fatty acids
```
294
Exotoxins
Produced mostly by Gram+ve bacteria
| Released into surroundings
295
Endotoxins
Exists as part of outer portion of cell wall of Gram-ve
| Freed when cell dies and cell wall breaks
296
Ddx of cellulitis
Stasis ulcer
Impetigo
Stasis dermatitis
297
What is erysipelas confined to
Dermis
Well detracted
Typically in cheeks, face and nose
298
Palpation of erysipelas
Warm
Tender
Smooth
299
Mx of abscess
Incise and rain areas
Hosp admission
Abx
IV
300
Ecthyma vs impetigo
Ecthyma is a deep infection than impetigo (invasion of demris)
Unlike impetigo, ecthyma heals w/ scarring (eschar)
301
Pathogen causing ecthyma gangrenous
Pseudomonas aeruginosa
302
Skin manifestation of systemic infections
Petechial rash of meningocoaal septicaemia
Ecthyma gangrenosum of pseudomonas in blood stream
Splinter haemorrhage of endocarditis
Rash as part of systemic infection (e.g. chicken pox, measles)
Primary site of herpes simplex infection
Toxin mediated skin disease
303
Features of TSS
```
High fever
Rash that resembles sunburn followed by desquamation
D+V
Hypotension
Multiorgan failure
```
304
What can TSS be caused by
Use of tampons
305
What is Scalded Skin Syndrome (SSS)
Flaccid blisters and superficial denudation/ desquamation
| AKA Ritter's disease
306
Desquamation
Peeling of skin
| Skin cels are created, clogged away and replaced
307
Who does SSS affect
Children <5
| Immunocompromised adults
308
PVL
Panton-Valentine-Lecocidin
A toxin produced by staph A that kills leucocytes
Has been proven to cause recurrent, persistent skin infections e.g. abcesses
309
Why is PVL screened for in hospitals
Necrotising infections - risk of fatal pneumonia
310
How is MRSA killed before pts go to surgery
Nasal decontamination w/ mupirocin wash
311
Streptococcal toxinoses
Streptococcal skin infections are caused by Strep. Pyogenese (Gp A strep)
Strep impetigo develops independently of strep URTI
312
Streptococcal toxins
Pyrogenic toxins - causes of rash seen in scarlet fever and streptococcal TSS
Streptolysins O and S: dame mammalian cells
Streptokinase: plasminogen --> plasmin, lysis of clots
Hyaluronidase: disrupts ground substance
313
A/c glomerulonephritis and skin infections
Occurs more often after skin infections then throat infections
314
Meningococcal petechiae
Endotoxin causing endothelial damage
Increased permeability and capillary leakage (micro haemorrhage)
Activation of coagulation cascade --> microvascular thrombosis
NB non blanching 'tumbler test'
315
Initial lesion causing necrotising fasciitis
Can be trivial e..g minor abrasion, insect bite, injection (IVDU) and visible skin lesion
316
Initial px of necrotising fasciitis
That pf cellulitis (v hard and indurated) - can advance rapidly or slowly
As it progresses there's systemic toxicity - high temp, disorientation, lethargy
317
Examination of local sites of necrotising lesion
Typically reveals cutaneous infl, oedema and and discolouration or gangrene and anaesthesia
318
Fournier's gangrene
Associated w/ DM, this is an extensive necrotising infection of the genitals, perianal, scrotum and perineal region and groins
Life threatening - surgery within 1hr
319
Causative organisms of Fournier's gangrene
Gram -ve
GpA strep
Anaerobes
320
Epidemiology of Fournier's gangrene
M > F
321
Anaerobic/ clostridial gangrene
Traumatic or surgical wounds can be come infected w/ Clostridum species
322
How does C. tetani causes clostridial gangrene
Gains access to the tissues through of the ski, but the disease it produces of the powerful exotoxin
323
Causes of gas gangrene/ clostridia gangrene
Several species of clostridia - C. pefringens is the most common
324
Diabetic foot ulcers causeative organisms
Can be caused by Staph A, Strep, anaerobes, E. coli, proteus, polymicrobial - infections
These can all become necrotic
325
Gram +ve cocci - aerobic
Pairs, tetrads: staph
| Chains: strep, enterococcus sp
326
Gram-ve rods - aerobic
E. coli
Preoteus
Pseudomonas
327
Gram +ve/-ve bacteia - anaerobes
Peptostreptococcus
| Clostridum
328
ZN stain
+ve for mycobacteria
329
Systemic viral infections seen in skin
```
Measles
VZV
Erythrovirus (aka parvovirus)
HHV-6
Rubella
```
330
Nail changes in psoriasis vs infections
Fungal - single nail, infl at nail bed, darker colour (brown discolouration)
Bacterial - green (pseudomonas)
Psoriasis - more symmetrical, more nails involved
331
What does the PASI score look at
% of body involvement
Redness
Induration
332
What might cause a flare up of psoriases
```
Stress
Medications
Infections e.g. step & guttate
Smoking
Drinking
Steroids - tapering down & pustular
Koebner
```
333
Drugs that may cause a flare of psoriases
BB
NSAIDs
Anti-malarial
Lithium
334
What group of syndromes are psoriasis associated with
Metabolic syndrome e.g. DM , increased insulin resistance, HTN, abdominal obesity
335
Treatment of mild atopic eczema
Emollients
| Mild potency topical steroids
336
Prescription of emollients
250g to 500g for children, 500g+ for adults
| Prescribe two containers for children - one available at school, nursery
337
Treatment of moderate atopic eczema
Emollients
Moderate potency topical steroids
Topical calcineurin inhibitors - tacrolimus
Bandages
338
Treatment of severe atopic eczema
```
Emollients
Moderate potency topical steroids
Topical calcineurin inhibitors - tacrolimus
Bandages
Phototherapy
Systemic treatments
```
339
How should emollients be applied
In downwards motion to avoid plugging follicles
| Folliculitis - avoid excessive rubbing in of any topical if there’s a possibility of histamine release
340
Skin barrier defect as cause of atopic eczema
Inherited abnormalities in fillagrin expression
Water is lost
Irritants and allergens may penetrate skin barrier
341
Th2 response as a cause of atopic eczema
Infl induced by Th2 response exacerbates barrier defect
```
Ceramides reduced
Fillagrin reduced
Antimicrobial peptides reduced
Bacteria colonise and infect skin
Infections harder to control
```
342
Why is urticaria described as transient
Usually doe not last more than 24hrs in same place
343
Distinctive feature of anaphylaxis vs angiodema
Anaphylaxis is characterised by circulatory shock e.g. hypotension
Angiodema is just swelling
344
Types of urticaria
Ordinary E.g. physical - clothing. Can be a/c, c/c, or episodic
Mechanical
Aquagenic
Solar
345
Dx of urticaria/ angiodema
Hx is typically sufficient
Examination - distribution, morphology and size of wheals
Further ix may be needed e.g. urticarial vasculitis (ESR, autoimmune screen), skin prick test
346
Dermatographism
Exaggerated wheal and flare response that occurs within minutes of skin being touched
Most common form of physical or c/c inducible urticaria
347
Treatment of urticaria/ angiodema
Stop offending drug
Avoid trigger
Give non-sedative antihistamine op to qid - fexofenadine
Short course of pred
Stronger agents - anti-IgE, cyclosporin, calcineurin inhibitors,
348
Paronychia
Infection AROUND nail caused by staph or strep
349
Treatment of paronychia
Incision and drainage using local anaesthetic
| Follow up w/ po abx
350
What is the stream basale bound to
Basement membrane by hemidesmosomes
351
What IL are involved in the pathogenesis of psoriasis
IL-17 and IL-23
352
Why are oral steroids contraindicated in psoriasis
Treats psoriasis initially but causes very bad flare once stooped
353
How many session can be given for narrow band UVB in psoriasis
Max 30-36
354
When is narrow band UVB contraindicated in psoriasis
If pt has several moles
355
Different retinoids and their indications
Isotet for acne
Alitret for hand eczema
Acitret for psoriasis
356
What viral infections should be screened before starting ciclosporin
HPV
357
Causes of erythema nodusum
NODUSUM
```
NO - no cause
D - drugs E.g. dapsone, sulphonamides
O - OCP
S - sarcoidosis
U - ulcerative colitis/ Crohn’s
M - micro e.g. TB, strep, toxoplasmosis
```
358
Mx of SSS
IV abx
Topical fusidic acid
Supportive treatment
359
When is Nikolsky's sign positive
SSS
TEN
Pemphigus vulgaris
360
What can you get get SSS secondary to
Initial impetigo
361
Abx of choice to treating TSS
IV clindamycin and meropenem
362
Treatment of severe TEN
IVIg +/- plasmapheresis
363
Treatment of scarlet fever
Oral penicillin V
364
Algorithm for topical treatment of psoriasis
All pts need to use emollients
1st line - potent steroid (betnovate) and Vit D (Dovonex) applied at diff times
2nd line - stop steroid, use Vit D BD
3rd line - stop Vit D, use potent steroid BD
Dithranol and coal tar are alternatives
365
Side effects of ciclosporin
```
Hypertrophy of gums
Hypertrichosis
HTN
Hyperkalaemia
Hyperglycaemia
```
