Cutaneous drug eruptions

Question 1

Urticaria

Answer 1

Type 1 anaphylactic reaction

Question 2

Pemphigus and pemphigoid

Answer 2

Type II cytotoxic reaction

Question 3

Purpura/rash

Answer 3

Type III immune complex mediated reaction

Question 4

T-cell mediated erythema/ rash

Answer 4

Type IV cell mediated delayed hypersensitivity reaction

Question 5

Are immunologically mediated reactions dose dependent?

Answer 5

No

Question 6

Eczema immunologically mediated?

Answer 6

No

Question 7

Are eczema, drug induced alopecia, phototoxicity, skin erosion/atrophy (from topically applied 5FU/steroids), Psoriasis, pigmentation, cheilitis, xerosis dose dependent?

Answer 7

Yes, because these are not immunologically mediated

Question 8

Concommittent disease that may make you more likely to have drug eruption?

Answer 8

Viral infections (HIV/EBV/CMV)
Cystic fibrosis

Question 9

Why can NSAIDs cause reaction?

Answer 9

They have beta lactam ring –> this is a risk

Question 10

Most common type of drug eruption?

Answer 10

Xanthematous drug reaction

Question 11

What type of hypersensitivity is a xanthematous drug reaction?

Answer 11

Type IV (T cell mediated)

Question 12

When would you get xanthematous reaction?

Answer 12

4-21 days after taking first drug

Question 13

Pattern of xanthematous drug reaction distribution?

Answer 13

Wide spread, symmetrically distributed
Mucous membranes usually spared

Itch is common
Fever is common

(can progress to severe)

Question 14

Indicators of a potential severe reaction? (xanthematous)

Answer 14

Involvement of mucous membrane and face. • Facial oedema & erythema.
• Widespread confluent erythema.
• Fever (>38.50C).
• Blisters, purpura, necrosis.
• Lymphoadenopathy, arthalgia.
• Shortness of breath, wheezing.

Question 15

PECANS SAP

xanthematous reaction

Answer 15

Penicillins
Erythromiciin
Chloramphenicol
Allopurinol
NSAIDS
Sulfonamide abx

Streptomicin
Anti-epileptics
Phenytoin

Question 16

Urticaria usually mediated by which Ig?

Answer 16

IgE

IgE

Usually an immediate IgE- mediated hypersensitivity reaction (Type I) after rechallenge with drug (β-lactam antibiotics, carbazepine, many other drugs).
Or
– Direct release of inflammatory mediators from Mast cells on first exposure (aspirin, opiates, NSAIDs, muscle relaxants, vancomycin, quinolones)

Question 17

Drugs which could cause acne?

PAILS

Answer 17

Phenytoin
Androgens
Isoniazid
Lithium
Steroids

Question 18

Drugs which could cause acute generalised exanthematous pustulosis? (AGEP)
(CAbAm)

Answer 18

Calcium channel blockers
Antibiotics
Antimalarials

Question 19

Drug induced bullous pemphigoid?

FAP …. lol

Answer 19

Furosemide
ACE inhibitors
Penicillin

Question 20

Drug which could trigger linear IgA disease?

Answer 20

Vancomycin

Question 21

Describe a fixed drug eruption appearance?

Answer 21

Well demarcated, round/ovoid plaque
Red, painful

Hands, genitalia, lips, occasionally oral mucose

Question 22

Will a fixed drug eruption resolve when you stop taking that drug?

Answer 22

Yes but you have persistent pigmentation

-can reoccur on the same site on re-exposure to the drug

Question 23

Drugs associated with fixed drug eruptions?

Try Doing Nothing Cause Paracetemol

Answer 23

Tetracylcine
Doxycyline
NSAIDS
Carbamazepine
Paracetemol

Question 24

Drugs which would cause SJS/TEN

Suck Candy Cause Nobody Pays Today

Answer 24

Sulfonamide
Cephalosporins
Carbamezepine
NSAIDs
Phenytoin
Tramadol

Question 25

Drug reaction with eosinophilia and systemic symtpoms? | (VAANS

Answer 25

``` Vancomycin Allopurinol Anti-convulsants NSAIDs Sulfonamides ```

Question 26

Are phototoxic cutaneous drug reactions immunologically mediated?

Answer 26

No, they will arise in anyone if there is enough appropriate drug and the appropriate wavelength of light

Question 27

Waveband of light that usually causes phototoxic drug reaction?

Answer 27

UVA/visible light | Can occur indoors through window and glass

Question 28

When you react to psoralen, when would you develop erythema and pigmentation?

Answer 28

3-5 days after

Question 29

Which drugs will exxagerate sunburn? (QT)

Answer 29

Qunine, thiazides

Question 30

Which drugs will give you telangiectasia in the sun? (CT)

Answer 30

Calcium channel blockers cause Telangiectasia

Question 31

Immediate prickling with delayed erythema and pigmentation?

Answer 31

Chlorpromazine, amiodarone

Question 32

Why is skin testing NOT indicated for serum sickness reactions (TYPE III) or for T-cell mediated reactions (TYPE IV)?

Answer 32

Can potentially trigger SJS, TEN and DRESS

Question 33

Test if you think it is a suspected allergic contact dermatitis (type IV)?

Answer 33

Patch and photopatch test

Question 34

Management of cutaneous drug reaction?

Answer 34

Discontinue the drug (if possible). Use an alternative. • Topical steroids may be useful. • Antihistamines may be useful. • Allergy bracelets are useful for some drugs. • Drug eruptions should be reported via the Yellow Card scheme (Medicines and Healthcare products Regulatory Agency)