This substance, which is often used by dermatologists to treat erythema nodosum and sporotrichosis, can cause halogenoderma.
Saturated solution of potassium idodide (SSKI)
*Note: "KI" is the chemical abbreviation for potassium idodide
What inflammatory infiltrate is typically present in halogenoderma?
This neutrophilic drug reaction, which is often confused with Sweet's syndrome, is likely due to a toxin insult to the eccrine glands.
Neutrophilic eccrine hydradenitis (NEH)
*Note: NEH is most commonly seen in patients with acute myelogenous leukemia receiving cytarabine
Activation of which two viruses might be linked to the pathogenesis of DRESS?
HHV 6 and HHV7
True or false: facial edema is a characteristic feature of DRESS.
What is the most common cause of mortality associated with DRESS?
Fulminant liver failure
What is the first-line therapy for DRESS?
Systemic steroids (topical steroids can be used alone in mild cases)
Fixed drug eruptions (FDE) can occur anywhere on the body, however certain sites are more commonly involved. These include:
The lips, face, hands, feet, and genitalia
What drug most commonly causes the non-pigmented variant of FDE?
What drugs are most commonly implicated in FDEs?
Sulfonamides, NSAIDs, barbiturates, tetracyclines, and carbamazepine
What drug is most commonly associated with drug-induced linear IgA bullous disease? What group of drugs is next most commonly associated?
Beta lactam antibiotics
True or false: pseudolymphoma (i.e. drug induced lymphoma) tends to have a biologically aggressive course, and typically meets the diagnostic criteria for Non-Hodgkin's lymphoma.
False; it has a benign biological behavior and does not satisfy the criteria for non-Hodgkin lymphoma
*Note: complete recovery typically occurs several weeks after withdrawing the drug
**Note: pseudolymphoma can simulate either a T- or B-cell lymphoma.
True or false: DRESS often recurs when the systemic steroid used to treat it is withdrawn. Thus, a long slow taper is typically necessary.
True or false: drug-induced alopecia always causes anagen effluvium.
False; it can produce either telogen or anagen effluvium
Do chemotherapy drugs cause an anagen or telogen effluvium?
* This explains the more rapid onset of alopecia that typically occurs with chemotherapy (anagen effluvium occurs within 2-3 weeks of drug exposure, while telogen effluvium occurs within 2-4 months of drug exposure)
True or false: anti-convulsants, beta-blockers, lithium, and retinoids can all cause telogen effluvium.
Other than chemotherapy drugs, list three other drugs that can cause an anagen effluvium.
*This is a tough one!
Bismuth, gold, and thallium
True or false: it's a myth that patients with straight hair can sometimes regrow curly hair after chemotherapy.
False! This is not a myth. Sometimes patients with straight hair can regrow curly hair.
What is a potential complication of patients with psoriasis who are receiving chemotherapy?
Necrosis of the psoriatic plaques
Give examples of drugs that can cause psoriasis with a short, intermediate, and long latency period (i.e. how soon after giving the drug the psoriasis occurs).
Short: terbinafine and NSAIDs
Intermediate: antimalarials and ACE inhibitors
Long: lithium and β-blockers
Other than corticosteroids, list two drugs that are associated with acneiform eruptions.
Androgens and lithium
True or false: chloroquine and sunitinib are two drugs that can lead to lightening, or complete depigmentation of the hair.
What changes does 5-FU typically cause in the nails?
What pigmentary changes can the drug sunitinib induce on the hair?
Either ligtening OR darkening of the hair
List the seven drugs most commonly implicated in drug-induced hyperpigmentation of the skin.
*Image: amiodarone-induced hyperpigmentation
What drug is most commonly implicated in pseudoporphyria?
True or false: immunosuppressed patients have an increased risk of immunologically mediated adverse drug reactions (ADRs).
True; although this seems paradoxical, they have a 10 - 50 time increased risk of immunologically mediated ADRs
What is the difference between anaphylaxis and an anaphylactoid reaction?
Anaphylaxis = Ag binds to IgE on surface of mast cells, basophils, degranulation, release histamine
Anaphylactoid = non-immunologic release of histamine +/- inflammation
For patients who have ACEi-induced angioedema, can you substitute with an ARB? Why?
No, is a different class of drugs but receptor antagonist are still associated with angioedema
What are some histologic differences between AGEP and pustular psoriasis?
AGEP = superficial dermal edema, vasculitis, eosinophil exocytosis, keratinocyte necrosis
Pustular psoriasis = acanthosis
What are the most common visceral involvement and leading cause of death in DRESS?
At what CD4 count do you commonly see increased susceptibility to drug reactions
What are the types of immunologic reactions according to Gell-Coombs classification?
IgE dependent (type I)
- Urticaria, Angioedema, Anaphylaxis
Cytotoxic (type II) [Ab vs. fixed Ag]
- Thrombocytonpenia --> petechiae
Immune-complex dependent (type III)
- Vasculitis, Serum-sickness, Urticaria
Cell-mediated, delayed type (type IV)
- Exanthamatous, Fixed, Lichenoid drug erruption
What are the clinical manifestations of anaphylaxis?
Where is the pathology in leukocytoclastic vasculitis (what vessels)?
What is the primary lesion in AGEP?
non-follicular sterile pustules
AGEP must be differentiated from acute pustular psoriasis of Von Zumbusch. How?
AGEP = Acute
AGEP = drug history present
What percentage of Sweet's syndrome is drug-induced?
- All-trans-retinoic acid
- G-CSF (stimulate neutrophil differentiation)
- GM-CSF (stimulate neutrophil proliferation)
True or False: neutrophilia is present in drug-induced Sweet's syndrome
What is the most common drug that causes neutrophilic eccrine hidradenitis?
Cytarabine (AML Rx)
What toxic anticonvulsant metabolite DRESS patients cannot detoxify?
What are the four types of fixed drug eruptions?
Flagellate linear hyperpigmentation is caused by what drug?
True or Flase: in drug-induced systemic LE, ds-DNA antibodies are typically present.
False; Anti-histone antibodies are usually elevated (in 95% of patients)
True or Flase: Abrupt cessation of mitotic activity of stem cells of the hair matrix occurs in Telogen Effluvium
This occurs in Anagen Effluvium