Disease Profile: Other Flashcards
1
Q
Describe the first line management of mild-moderate acne
A
Topical treatment for 3/12 then review - benzoyl peroxide or retinoids +/- topical antibiotic
2
Q
Name three drugs associated with Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN)
A
Antibiotics (penicillin, sulfonamides, cephalosporins), carbamazepine, phenytoin
3
Q
Why is biotin important?
A
Essential co-factor for carboxylase enzymes
4
Q
Describe the clinical presentation of vitamin B2 deficiency
A
Cheilosis, angular stomatitis, painful red dry tongue
5
Q
What is acute generalised exanthematous pustulosis?
A
Drug reaction involving widespread rash with numerous small, non-follicular, sterile pustules around the neck, axillae and groin
Usually starts a few days after drug exposure and resolves with peeling
6
Q
What is discoid eczema?
A
Ezcema which occurs in circular or oval patches, patients often atopic, very often infected
7
Q
Describe the management of a drug eruption
A
Discontinue drug if possible
Topical steroids may help
Antihistamines may help if type I or with symptoms of itch
8
Q
Name 3 options for the management of eczema in secondary care
A
Phototherapy - mainly, systemic immunosuppression, biological agents (for atopic - target IL-4/IL-13)
9
Q
Why is skin prick testing not first line for testing of allergy if it is more specific and sensitive?
A
Anaphylaxis risk
10
Q
Describe the clinical features of a type II allergic adverse drug reaction
A
Cytotoxic reactions - pemphigus and pemphigoid
11
Q
Describe the pathophysiology of contact irritant dermatitis
A
Non-specific physical irritation rather than a specific allergic reaction e.g. soap, water, cleaning products, water, nappy rash, ‘lip-lick’ chelitis
12
Q
Describe the clinical presentation of acne
A
Non-inflammatory lesions (comedones) - blackheads and whiteheads
Inflammatory lesions - papules, pustules, cysts, nodules on an erythematous base
13
Q
When are mild topical steroids indicated in psoriasis?
A
Flexural disease, palmar plantar disease and scalp psoriasis
14
Q
What occurs in the allegic stage of a type I hypersensitivity (allergy)?
A
On re-exposure to allergen, the allergen will bind to IgE coated mast cells → cell degranulation (release of histamine and other inflammatory mediators)
15
Q
What is a cutaneous drug eruption?
A
Adverse drug reaction of the skin - can be immunologically mediated (allergic) or non-immulogically medicated (non-allergic)
16
Q
How would you manage a patient under 12 with mild-moderate acne which has not improved after 3 months of topical therapy?
A
Erythromycin or clarithromycin BD
17
Q
Describe the clinical presentation of acute eczema
A
Papulovesicular, erythematous lesions, itch, ill-defined, oedema, ooze/scaling/crusting
18
Q
What causes venous (stasis) dermatitis?
A
Incompetent veins in the leg, commonly due to increased venous pressure by obesity, leak RBCs into the tissue resulting in swelling, haemosiderin, pigmentation and inflammation
19
Q
Describe the clinical presentation of psoriasis
A
Symmetrically distributed, red scaly plaques with well-defined edges, itching
Commonly on scalp, elbows and knees
20
Q
What is the diagnostic criteria for atopic eczema?
A
Itching + 3 or more of:
Visible flexural rash
History of flexural rash
Personal/family history of atopy
Generally dry skin
Onset before age 2
21
Q
What should all patients with type I hypersensitivity (allergy) be given to use in the event of anaphylaxis?
A
Adrenaline autoinjector
22
Q
How would you define acne that consists of scattered comodones, papules and pustules?
A
Mild
23
Q
What is the safest method of investigating a type I hypersensitivity (allergy)?
A
Specific IgE blood test
24
Q
What are target lesions?
A
Annular shaped macules that are raised with a red rim and centre with a wedge of normal skin inbetween; feature of erythema multiforme and toxic epidermal necrolysis
25
Which investigation would you perform in suspected contact allergic dermatitis?
Patch testing
26
When would you consider a wound swab of a leg ulcer?
If ulcer increasingly painful/exudate/malodour/enlarging
27
How would you define acne that consists of numerous papules, pustules and mild atrophic scarring?
Moderate
28
What is sebopsoriasis?
Overlap of seborrhoeic dermatitis and psoriasis, affects scalp, face, ears and chest, colonised by malassezia
29
Describe the clinical features of a type IV allergic adverse drug reaction
T cell-mediated delayed hypersensitivity reactions - erythema/rash
30
Name three drugs associated with acneiform drug eruptions
Glucocorticoids (steriod acne), androgens, lithium
31
When is dithranol indicated in psoriasis?
Short contact regiments for stable chronic plaque disease
32
Describe the histology of lichen planus
Irregular sawtooth acanthosis
Hypergranuloss and orthohyperkeratosis
Band-like upper dermal infiltrate of lymphocytes
Basal damage with formation of cytoid bodies
33
Describe the clinical presentation of a dermatofibroma
Unchanging firm lesion, skin-coloured or brownish
Occasionally itchy
34
Where is acne most common and why?
Distribution reflects sebaceous gland sites - face, upper back, anterior chest
35
When would you consider systemic treatment in mild-moderate acne?
Poor response to topical treatment at 3 month review
36
How may you identify the drug behind a cutaneous drug eruption if the causative drug is not obvious from history/examination?
If suspect phototoxic drug reactions - phototesting
Biopsies can identify type of drug reaction and exclude other diseases
Patch and photopatch test, skin prick testing
37
How might you investigate a suspected dermatofibroma if you aren't certain enough to diagnose clinically?
Dermoscopy, biopsy
38
What causes dyshidriotic eczema (pompholyx eczema)?
Occurs when there is a very sudden acute flare up of eczema and the spongiotic vesicles join together, resulting in the formation if intensely itchy tiny blisters developing in the hands and feet
39
What is the second-line treatment for a patient with type I hypersensitivity (allergy)?
Corticosteriods
40
When is systemic (immune) therapy indicated in psoriasis?
Severe or non-responsive disease
41
Describe the pathophysiology of venous ulcers
1. Elevation of venous pressure in the legs e.g. by abdominal obesity which resists venous return from the legs
2. Veins dilate and valves become incompetent, varicose veins develop
3. Increased hydrostatic pressure in the vessels → red blood cell leakage into the tissue resulting in swelling, haemosiderin, pigmentation and inflammation
4. The skin cannot heal well due to poor blood supply, so begins to break down
42
What lifestyle advice would you give to a patient with type I hypersensitivity (allergy)?
Allergen avoidance
43
What causes arterial leg ulcers?
Insufficient blood supply due to peripheral vascular disease
44
Name three drugs associated with drug reaction with eosinophilia and systemic symptoms (DRESS)
Sulfonamides, anticonvulsants, allopurinol
45
What is nodular pruigo?
Skin condition characterised by very itchy firm lumps, associated with atopic eczema; more common in black people
46
Describe the histology of acute eczema
Inflammatory infiltrate (lymphocytes) in the upper dermis, spongiosis, vesicles
47
Describe the clinical presentation of fixed drug eruptions
Well demarcated round/ovoid plaques
Can present as eczematous lesions, papules, vesicles or urticaria
Red, painful
Occur on hands, genitalia, lips, occasionally oral mucosa
48
What occurs in the sensation stage of a type I hypersensitivity (allergy)?
Production of specific IgE by B cells (helped by T cells) in response to initial allergen exposure, residual IgE antibodies bind to circulating mast cells via Fc receptors
49
Describe the clinical features of photo-induced/photosensitive eczema
Caused by a reaction to UV light so there is usually a well defined edge e.g. cut-off collar
Patients often atopic
50
Name three patient risk factors for a cutaneous drug eruption
Young adults, female, concomitant disease
51
Describe the clinical features of adult eczema
Generalised dryness and itching, hand eczema may be the primary manifestation
52
How would you manage moderate eczema?
Moderate topical steroid e.g. betamethasone valerate 0.025%, if face affected start with mild steroid
53
Where do the majority of venous ulcers tend to occur?
Gaiter area
54
Why is vitamin B2 important?
Essential co-factor in numerous metabolic reactions
55
Describe the pathophysiology of phototoxic drug reactions
Drug metabolites interact with UV light (usually triggered by UVA) → free radical release → direct tissue or cell injury → severe rash
56
Name three drugs associated with drug-induced bullous pemphigoid
ACE inhibitors, penicillin, furosemide
57
What is small plaque psoriasis?
Plaques \<3 cm, often late set of onset
58
When is phototherapy indicated in psoriasis?
More severe or widespread disease, first line for guttate psoriasis
59
Which patient group are dermatofibromas more common in?
Immunosuppressed patients
60
What is eczema herpeticum?
Disseminated viral infection (herpes simplex) characterised by monomorphic punched-out lesions; most commonly seen as a complication of atopic eczema
61
Describe the pathophysiology of contact allergic dermatitis
Type IV hypersensitivity (T cell) reaction to external antigen e.g. nickel, chemicals, topical therapies, plants
62
Name a drug which can trigger linear IgA disease
Vancomycin
63
Describe the clinical presentation of vitamin K deficiency
Bleeding tendency, seen in the skin as purpura and easy bruising
64
Which patients with psoriasis should use emollients?
Should be used by all patients
65
What is drug reaction with eosinophilia and systemic symptoms (DRESS)?
Widespread erythema, facial oedema, fever, lymphadenopathy and hepatosplenomegaly which usually starts 2-6 weeks after initial exposure
66
Name two endocrine disorders which predispose to acne
PCOS, hyperandrogenism
67
How would you investigate vitamin K deficiency?
Measure coagulation and serum vitamin K
68
Which physical findings are associated with phototoxicity caused by quinine, thiazides, demeclocycline?
Exaggerated sunburn
69
How would you define acne that consists of numerous papules, pustules, severe atrophic scarring, cysts, nodules?
Severe
70
What is rosacea?
Chronic inflammatory skin disease that may be triggered by a number of factors e.g. alcohol, stress
71
Which investigation is used to confirm anaphylaxis?
Serum mast cell tryptase level
72
Describe the clinical presentation of type I hypersensitivity (allergy)
Urticaria, angioedema, wheeze/asthma, anaphylaxis
73
Describe the clinical presentation of vitamin A deficiency
Keratotic follicular papules on the thighs and upper arms, dry skin
74
Describe the clinical presentation of rosacea
Recurrent facial flushing followed by erythema with papules and pustules (rash)
75
Describe the clinical presentation of vitamin B6 deficiency
Dermatitis of face, scalp, neck, shoulders, buttocks and perineum, glossitis
76
Describe the clinical presentation of biotin deficiency
Hyperkeratosis around hair follicles, bent hairs, inflamed gums, poor wound healing
Fatigue, malaise, muscle and bone pain
77
Describe the management of severe cystic acne
Commence systemic antibiotic therapy and refer immediately for consideration of systemic isotretinion treatment (roaccutane)
78
Describe the clinical features of a type III allergic adverse drug reaction
Immune complex mediated reactions - purpura/rash
79
Describe the pathophysiology of atopic eczema
Defective skin barrier allows access/sensitisation to allergen and promotes colonisation by microorganisms
80
Name three drug risk factors for a cutaneous drug eruption
Chemistry - β-lactam compounds, NSAIDS, high molecular weight/hepten-forming drugs
Topical route
Higher dose/longer half-life
81
What is erythrodermic psoriasis?
May or may not be proceeded by another form of psoriasis, acute and chronic forms, may result in systemic illness with temperature dysregulation, electrolyte imbalance, cardiac failure
82
What causes stasis (varicose) dermatitis?
Physical trauma to skin of the lower legs caused by increased hydrostatic pressure of the blood (venous insufficiency) resulting in extravasion of RBCs
83
How would you investigate biotin deficiency?
Measure serum biotin
84
Describe the effect of anaphylaxis on breathing
Bronchospasm (wheeze) with tachypnoea
85
Describe the effect of anaphylaxis on circulation
Hypotension (+ collapse) and/or tachycardia
86
Describe the effect of anaphylaxis on the airway
Pharyngeal or laryngeal oedema
87
What is the third-line treatment for rosacea?
Isotretinoin
88
What lifestyle advice would you give to a patient with rosacea?
Avoid triggers
89
Which aspect of the history is very important in diagnosing a type I hypersensitivity (allergy)?
Consistent reaction with every exposure to allergen
90
Describe the management of lichen planus
Topical steroid + antihistamine
91
Why does acne occur at puberty?
Increased androgens at puberty which causes hypercornification and can also increase sebum production
92
Name the most common lichenoid disorder
Lichen planus
93
Mutations in which gene is associated with severe/early onset atopic eczema?
Mutations in fillagrin gene - involved in skin barrier function
94
What is the Koebner phenomenon?
Appearance of new skin lesions on previously unaffected skin secondary to trauma; seen in eczema and psoriasis
95
What is the second-line treatment for rosacea?
Topical therapies + oral antibiotics (doxycycline)
96
Crusting of an eczema lesion indicates secondary infection by which organism?
Staph. aureus
97
What causes psoriasis?
Inflammation triggered by environmental factors in genetically susceptible individuals (HLA genes)
98
Describe the clinical features of a type I allergic adverse drug reaction
Anaphylactic reactions, urticaria
99
What is chronic plaque psoriasis?
Psoriasis that is treatment resistant
100
How would you manage mild eczema?
Topical steroid
101
What is wound bed preparation with reference to a leg ulcer?
Removal of devitalized tissue by debridement, can be autolytic, sharp debridement, biological or surgical
102
Describe the histology of psoriasis
Thickened epidermis with more keratin in the keratin layer, retention of nuclei in keratinocytes (parakeratosis), accumulation of inflammatory cells, particularly neutrophils, in the upper epidermis (micro-abscesses), elongated rete pegs
103
What causes lichen simplex?
Physical trauma to skin - scratching
104
Define a type I allergy
IgE-mediated antibody response to external antigen
105
Describe the clinical presentation of an exanthematous drug eruption
Widespread symmetrically distributed rash 4-21 days after taking drug
Pruritus and mild fever common
Usually mild and self-limiting but can progress to a severe life-threatening reaction
106
How would you investigate vitamin A deficiency?
Measure serum vitamin A
107
Define psoriasis
Common chronic inflammatory dermatosis
108
When would you consider a challenge test in diagnosis of allergy?
If skin prick test negative but history very convincing
109
When should you aim to heal simple venous ulcers by?
12 weeks
110
Name three features which indicate an exanthematous drug eruption may be severe (life-threatening)?
Involvement of mucous membrane and face, fever \>38.5℃, facial erythema and oedema
111
What is acrodermatitis enteropathica?
Autosomal recissive disorder resulting in insufficient zinc absorption
112
Which patient group is most likely to develop rosacea?
More common in females, age 30-40 years
113
Why is vitamin A important?
Responsible for epithelial proliferation, keratinsation and development
114
How would you investigate vitamin B2 deficiency?
Measure the activity coefficient of erythrocyte glutathione reductase
115
Name a medication sometimes used for asthma in the context of allergy
Mast cell stabilisers (e.g. sodium cromoglycate)
116
Which physical findings are associated with phototoxicity caused by nalidixic acid, tetracyclines, naproxen, amiodarone?
Increased skin fragility
117
Which physical findings are associated with phototoxicity caused by psoralens?
Delayed 3-5 days erythema and pigmentation
118
What are phototoxic cutaneous drug reactions?
Non-immunological skin reaction arising in an individual exposed to enough photo-reactive drug and light of the appropriate wavelength
119
List some general measures for the management of eczema
Remove potential triggers, avoid irritants, loose cotton clothing, emollients
120
How would you manage severe eczema?
Potent topical steroid e.g. betamethasone valerate 0.1% on inflamed areas
For more sensitive areas moderate potency e.g. betamethasone valerate 0.025%
121
Define a chronic leg ulcer
Open lesion between the knee and ankle joint that remains unhealed for at least 4 weeks
122
How would you investigate underlying arterial disease in a patient presenting with a leg ulcer?
ABPI
123
Describe the clinical presentation of vitamin B3 deficiency
Dermatitis, delirium, diarrhoea, death
124
Describe the management of a leg ulcer
Pain control, de-sloughing agent if necessary, 4 layer compression bandaging
125
Which physical findings are associated with phototoxicity caused by chlorpromazine, amiodarone ?
Immediate prickling with delayed erythema and pigmentation
126
Name a disease associated with lichen planus
Hepatitis C
127
Describe the clinical features of nail psoriasis
Pitting, onycholysis, yellowing and ridging
128
What is guttate psoriasis?
Widespread small plaques most commonly after a streptococcal throat infection (strep throat), seen in patients 15-25, often resolves after several months
129
What causes the majority of chronic leg ulcers (60-80%)?
Venous blood stasis
130
Give three examples of immunological cutaneous drug reactions
Drug-induced alopecia, phototoxicity, atrophy due to topical steroids
131
What is the Auspitz sign?
Bleeding points where surface scale of psoriasis is removed
132
How would you treat telangiectasia + rhinophyma caused by rosacea?
Laser therapy
133
What is the first-line treatment for rosacea?
Topical metronidazole
134
Name two long term complications of rosacea
Rhinophyma (thickening of the skin), telangectasia
135
What is palmoplantar psoriasis?
Psoriasis involving palms and/or soles with keratoderma and painful fissuring
136
When would you consider skin prick testing for allergy?
If specific IgE negative but history convincing (suspect false negative)
137
Which immune cells will be present in drug-induced eczema?
Eosinophils
138
Where do the majority of arterial ulcers tend to occur?
The foot
139
Why is vitamin K important?
Essential cofactor for several blood coagulation factors
140
Describe the pathophysiology of acne
Increased androgens at puberty leads to hypercornification
Pilosebaceous units become plugged with keratin, and then become infected with corynebacterium acnes
Keratin and sebum build up to produce comedones
Rupture of comedones will cause the inflammatory lesions
141
Name the hypersensitivity reactions associated with drug-induced eczema
Type I or Type IV
142
What is the first-line treatment for a patient with type I hypersensitivity (allergy) after avoidance?
Anti-histamines
143
Why is vitamin C important?
Required for many metabolic pathways
Required for structure and function of skin so vital for wound healing
144
Describe the clinical presentation of acrodermatitis enteropathica
Infants develop diarrhoea, alopecia, dry/brittle hair and perioral, facial and acral dermatitis
145
What is a dermatofibroma?
Proliferation of fibroblasts induced by reaction to insect bite/minor trauma
146
Name three drugs associated with acute generalised exanthematous pustulosis drug eruptions
Antibiotics, calcium channel blockers, antimalarials
147
What are lichenoid disorders?
Conditions characterised by damage to basal epidermis
148
What is Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN)?
Life-threateing mucocutaneous drug reactions that are considered variants of a disease spectrum; they are characterised by varying extents of blistering/epidermal detachment and mucosal ulceration
149
How would you investigate vitamin B3 deficiency?
Clinical diagnosis - diffifult to measure niacin levels
150
Describe the clinical presentation of lichen planus
Itchy flat-topped violaceous papules on the flexor surfaces of wrist/forearm, ankles and legs
Oral lesions - lacy white lesions on the inside of the cheek
151
What is flexural psoriasis?
Psoriasis that affects body folds and genitals in smooth, well-defined patches which are colonised by candida yeasts
152
How would you manage a patient over 12 with mild-moderate acne which has not improved after 3 months of topical therapy?
Lymecycline OD OR doxycycline OD OR erythromycin/carithromycin BD
153
Which physical findings are associated with phototoxicity caused by calcium channel blockers?
Exposed telangiectasia
154
What are fixed drug eruptions?
Well demarcated round/ovoid plaques which recur at the same site each time a drug is taken and resolves with persistent pigmentation when drug stops
Can re-occur at same site on re-exposure to drug
155
Name two lasting effects of chronic acne on the skin
Atrophic scars, skin hyperpigmentation
156
Which regions are most commonly affected in infantile eczema?
Primarily involves face, scalp and extensor surfaces of the limbs, nappy area usually spared
157
What is unstable plaque psoriasis?
The rapid extension of existing or new plaques induced by infection, stress, drugs, or drug withdrawal
158
Why is vitamin B3 important?
Essential co-factor in numerous metabolic reactions
159
How can diabetes lead to chronic leg ulcers?
Diabetes impedes the normal stages of wound healing
160
Why is vitamin B6 important?
Co-enzyme for many processes
161
What is the most commonly used location for coal tar in the treatment of psoriasis?
Scalp
162
How would you investigate vitamin C deficiency?
Usually clinical diagnosis
163
Which patient group is most likely to develop acne?
Age 12-24, family history
164
What is acne?
Inflammatory condition of the pilosebaceous unit
165
What causes seborrheic eczema ('cradle cap')?
Probably a reaction to babies skin being colonised by natural bacteria
166
Describe the management of a dermatofibroma
Completely benign - reassure, no excision required
167
How would you investigate zinc deficiency?
Measure serum zinc
168
Define eczema
Spongiotic inflammation of the skin resulting in itchy skin lesions - similar clinical and pathological features but different pathogenic mechanisms (i.e. different causes)
169
What are urticarial drug reactions?
Usually an immediate IgE-mediated (type I) hypersensitivity reaction after rechallenge with drug, commonly β-lactam antibiotics, carbamazepine
Can also be due to a direct release of inflammatory mediators from mast cells on first exposure, commonly aspirin, opiates, NSAIDs, muscle relaxants, vancomycin, quinolones
170
What is the first line topical therapy for psoriasis?
Vitamin D analogues - calciptriol/calcitriol
171
Why is vitamin C important?
Essential co-factor in collagen formation e.g. hair, and for bone and teeth health
172
What are exanthematous drug eruptions?
Most common type of drug eruption involving a type IV reaction most commonly associated with antibiotics (beta-lactams, sulfonamides), NSAIDs, anti-epileptics (carbamazepine, phenytoin), alopurinol and chloramphenicol
173
Describe the clinical presentation of chronic eczema
Thickening (lichenification), elevated plaques, increased scaling, excoriation, secondary infection
174
Name two treatment options for psoriasis in secondary care
Phototherapy, immunosuppression/immune modulation
175
Describe the clinical presentation of biotin deficiency
Rare - usually only seen in malabsorptive states or inadequate parenteral nutrition
Facial dermatitis, glossitis, alopecia
176
How would you investigate vitamin B6 deficiency?
Measure serum or urinary Vitamin B6
177
Describe the clinical presentation of acquired zinc deficiency
More common, may be due to increased elimination of zinc secondary to burns or infection
Dermatitic rash of hands and feet mainly
Growth retardation in children
178
Which regions are most commonly affected in childhood eczema?
Predominantly flexural
179
Name 4 drugs associated with fixed drug eruptions
Antibiotics (tetrecycline, doxycycline), paracetamol, NSAIDs and carbamazepine
180
When would skin prick testing be contraindicated in a patient with a cutaneous drug reaction?
Serum sickness reactions (Type III) or for Type IV reactions
Those with severe cutaneous adverse drug reactions
181
What would you advise a parent of a child with an allergy to do in the event of an acute allergic reaction?
1. At first sign of reaction give chlorphenamine
2. If allergic reaction does not resolve or gets worse over next 30 mins seek urgent medical help and give prednisolone
3. If child becomes blue or collapses give adrenaline IV and call 999
