Dermatology
Drug Reactions
Built from Dermatology, 5th Edition

What’s inside
19 sections · 181 slides
Overview
- What this topic covers
Overview and Epidemiology
How common drug eruptions are, and the language used to describe them
- Cutaneous adverse drug reactions: the basics
- SCARs: severe cutaneous adverse reactions
- The severe cutaneous adverse reactions (SCARs)
- How common are drug eruptions
- Why the true incidence is hard to pin down
- Skin reaction rates for drugs given to over 1000 patients
- Skin reaction rates for drugs given to over 1000 patients (continued)
- Drugs given to over 1000 patients with almost no skin reactions
- Additional reviews of specific types of cutaneous adverse reactions to drugs.
- Additional reviews of specific types of cutaneous adverse reactions to drugs. (continued)
- Additional reviews of specific types of cutaneous adverse reactions to drugs. (continued)
Pathogenesis and Genetics
Immune and non-immune mechanisms, and the HLA alleles that raise risk
- Two broad mechanisms behind drug rashes
- Mechanisms of cutaneous drug-induced reactions.
- Immune (Gell-Coombs) drug reactions
- Type IV is split into four sub-patterns
- How a drug becomes a target for the immune system
- Genetic risk: specific HLA alleles
- Specific HLA alleles that increase the risk of cutaneous drug reactions.
- Specific HLA alleles that increase the risk of cutaneous drug reactions. (continued)
- Specific HLA alleles that increase the risk of cutaneous drug reactions. (continued)
- Non-immunologic mechanisms in practice
Diagnostic Approach
Working out which drug is to blame, and what testing can and cannot tell you
- A rigorous approach to the suspected culprit
- Rigorous approach to determine the cause of a drug eruption.
- Timing and outcome after stopping the drug
- Time interval to onset by type of drug-induced eruption
- Mortality by type of drug-induced eruption
- Selected drugs responsible for each eruption type
- A working chart for the suspected reaction
- Blank drug eruption chart template
- Algorithm for a suspected adverse cutaneous drug reaction
- Features that suggest a severe cutaneous adverse reaction (SCAR)
- Laboratory tests: limited diagnostic value
- Patch testing: how often it identifies the culprit drug
- Patch testing: practical notes by reaction type
- Patch testing: practical notes by reaction type (continued)
- Rechallenge: useful but risky
Urticaria, Angioedema and Anaphylaxis
The immediate, IgE-mediated end of the drug-reaction spectrum
- Urticaria: features and timing
- Confirming and treating drug-induced urticaria
- Anaphylactoid reactions: urticaria without IgE
- Adverse reactions to radiocontrast media
- Angioedema
- Anaphylaxis
Exanthematous Drug Eruptions
The most common drug rash, and how to tell it apart from a viral exanthem
- Exanthematous eruptions: the most common drug rash
- What an exanthematous eruption looks like
- A second example of exanthematous drug eruption
- Course and warning signs
- Telling a drug rash apart from a viral exanthem
- Differential diagnosis algorithm for an exanthematous drug reaction (continued)
- Treating an exanthematous eruption
DRESS
Drug reaction with eosinophilia and systemic symptoms - a delayed, multi-organ hypersensitivity syndrome
- DRESS: an unusual, life-threatening reaction
- Timing and first signs of DRESS
- Internal organ involvement in DRESS
- Internal manifestations of DRESS/DIHS
- RegiSCAR scoring system for DRESS
- RegiSCAR scoring system for DRESS (continued)
- RegiSCAR scoring system for DRESS (continued)
- RegiSCAR scoring system for DRESS (continued)
- J-SCAR diagnostic criteria for DRESS/DIHS
- Testing and follow-up in DRESS
- Assessment and longitudinal evaluation of DRESS
- Assessment and longitudinal evaluation of DRESS (continued)
- Frequency of clinical and laboratory features in DRESS
- Frequency of clinical and laboratory features in DRESS (continued)
- DRESS/DIHS severity score
- DRESS/DIHS severity score (continued)
- Drugs associated with drug reaction with eosinophilia and systemic symptoms (DRESS).
- Drugs associated with drug reaction with eosinophilia and systemic symptoms (DRESS). (continued)
- Drugs associated with drug reaction with eosinophilia and systemic symptoms (DRESS). (continued)
- What drives DRESS, and how it is treated
Serum Sickness, Vasculitis and Neutrophilic Reactions
Immune-complex reactions and the pustular, neutrophil-driven drug eruptions
- Serum sickness-like eruption
- Drug-induced cutaneous small vessel vasculitis
- Acute generalized exanthematous pustulosis (AGEP)
- AGEP due to metronidazole
- AGEP - most commonly associated medications
- AGEP: diagnosis and treatment
- Sweet syndrome (acute febrile neutrophilic dermatosis)
- Halogenoderma
- Iododerma in a patient with late-stage chronic kidney disease
- Neutrophilic eccrine hidradenitis
SDRIFE
Symmetrical drug-related intertriginous and flexural exanthema
- SDRIFE: a symmetric flexural rash
- SDRIFE clinical diagnostic criteria
- SDRIFE - reported culprit drugs and vaccines
Bullous Drug Eruptions
Fixed drug eruption, linear IgA bullous dermatosis, drug-induced pemphigoid, and SJS/TEN
- Fixed drug eruption: the signature recurrence
- Fixed drug eruption - clinical spectrum, panels A-H
- Generalized bullous FDE (GBFDE)
- Fixed drug eruption histopathology
- Variants, drugs, and management of FDE
- Fixed drug eruption due to metronidazole
- Bullous fixed drug eruption
- Generalized bullous fixed drug eruption due to naproxen
- Fixed drug eruption due to naproxen
- Fixed drug eruption due to acetaminophen
- Vesicular fixed drug eruption of the glans penis
- Linear IgA bullous dermatosis (drug-induced)
- Drug-induced bullous pemphigoid
- Stevens-Johnson syndrome and toxic epidermal necrolysis
Photosensitivity
Phototoxic and photoallergic reactions - light plus a drug
- Phototoxicity: a predictable sunburn look-alike
- Photoallergy: an acquired immune reaction to light
- Drug classes linked to photoallergy
Chemotherapy-Related Reactions
Alopecia, mucositis, and the many faces of toxic erythema of chemotherapy
- Chemotherapy-induced alopecia
- Mucocutaneous side effects of antineoplastic agents, by reaction and responsible drug
- Mucositis (stomatitis) from chemotherapy
- Other common chemotherapy skin reactions
- Toxic erythema of chemotherapy (TEC)
- Toxic erythema of chemotherapy - terminology and variants
- Further chemotherapy skin reactions
- Paclitaxel-induced onycholysis with subungual hemorrhage
Targeted Therapy
Cutaneous side effects of the kinase inhibitors and monoclonal antibodies used in cancer care
- Why targeted therapy causes skin side effects
- Targeted therapy group A: antibody and kinase inhibitor classes
- EGFR inhibitors - cutaneous side effects
- EGFR inhibitors - cutaneous side effects (continued)
- BRAF inhibitors - cutaneous side effects
- BRAF inhibitors - cutaneous side effects (continued)
- MEK inhibitors - cutaneous side effects
- HER2-targeted antibodies - cutaneous side effects
- BCR-ABL / multi-target inhibitors - cutaneous side effects
- BCR-ABL / multi-target inhibitors - cutaneous side effects (continued)
- BCR-ABL / multi-target inhibitors - cutaneous side effects (continued)
- Anti-VEGF antibodies - cutaneous side effects
- Targeted therapy group B: further kinase inhibitor classes
- VEGFR / multi-kinase inhibitors - cutaneous side effects
- VEGFR / multi-kinase inhibitors - cutaneous side effects (continued)
- VEGFR / multi-kinase inhibitors - cutaneous side effects (continued)
- VEGFR / multi-kinase inhibitors - cutaneous side effects (continued)
- BTK inhibitors - cutaneous side effects
- CDK4/6 inhibitors - cutaneous side effects
- FGFR inhibitors - cutaneous side effects
- ALK / ROS1 inhibitors - cutaneous side effects
- PI3K inhibitors - cutaneous side effects
- Mucocutaneous side effects of mTOR and proteosome inhibitors.
- Mucocutaneous side effects of mTOR and proteosome inhibitors. (continued)
- Papulopustular (acneiform) EGFR-inhibitor reaction
- Preventing and treating the EGFR papulopustular reaction
- Papulopustular eruption due to cetuximab
- Papulopustular eruption due to erlotinib
- EGFR inhibitor-associated paronychia and pyogenic-granuloma-like lesions
Immunotherapy and Immune Checkpoint Inhibitors
Immune-related adverse events (irAEs) from anti-CTLA-4, anti-PD-1 and anti-PD-L1 therapy
- Immune checkpoint inhibitors: why the skin reacts
- Mucocutaneous and extracutaneous side effects of immune checkpoint inhibitors
- Lichenoid dermatitis due to anti-PD-1 antibody therapy
- Grading and managing ICI cutaneous side effects
- Inflammatory eruptions - Clinical findings by grade
- Inflammatory eruptions - Treatment recommendations by grade
- Inflammatory eruptions - ICI management by grade
- Bullous eruptions - Clinical findings by grade
- Bullous eruptions - Treatment recommendations by grade
- Bullous eruptions - ICI management by grade
- SCARs (SJS/TEN, AGEP, DRESS) - Clinical findings by grade
- SCARs (SJS/TEN, AGEP, DRESS) - Treatment recommendations by grade
- SCARs (SJS/TEN, AGEP, DRESS) - ICI management by grade
- Immunotherapy and older cancer drugs together
Hair and Mucosal Reactions
Drug-induced hair loss and oral/genital ulceration
- Drug-induced hair loss: two mechanisms
- Drug-induced alopecia by phase
- Hair growth changes and mucosal ulceration
Other Cutaneous Drug Reactions
Anticoagulant necrosis, HIV drug reactions, drug-induced lupus, pigmentary and psoriasiform reactions
- Anticoagulant-induced skin necrosis
- Granulomatous reactions and drug reactions in HIV infection
- Drug-induced lupus erythematosus
- Lymphomatoid drug reaction
- Pigmentary changes from drugs
- Drug-induced psoriasis
- Uncommon adverse mucocutaneous drug reactions.
Vaccines and Injection-Site Reactions
Local and systemic skin reactions to vaccines and injected medications
- Vaccine-related skin reactions
- Reactions localized to sites of injections of medications and vaccines (in addition to extravasation of those administered intravenously).
- Reactions localized to sites of injections of medications and vaccines (in addition to extravasation of those administered intravenously). (continued)
- Reactions localized to sites of injections of medications and vaccines (in addition to extravasation of those administered intravenously). (continued)
- Cutaneous side effects of insulin injections
- Vitamin K and mRNA vaccine injection-site reactions
- Injection-site reaction to lipid nanoparticle mRNA SARS-CoV-2 vaccine (“Moderna arm”)
Treatment and Prevention
Managing a drug reaction, and public-health measures to reduce SCARs
- The order of steps in managing a drug eruption
- Corticosteroids: not a universal answer
- Public health measures to prevent SCARs
- Key takeaways
References
Source citations from the chapter
- References
- References (continued)
- References (continued)
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- References (continued)
- References (continued)
- References (continued)
- Dermatology, 5th Edition (2-Volume Set)