Title: GZ / The Grenz Zone Season 1 / Episode 12
Tags: GZ DermnetNZ Waikato

Q: Erythroderma is also known as [...], and is descriptive of erythema and scaling affecting > [...]% BSA regardless of cause
A: exfoliative dermatitis; 80- 90
Back Extra: Complications
Skin vasodilation = ↓ peripheral resistance may lead to tachycardia, high
output cardiac failure, and edema
Extra blood flow in skin can disrupt thermoregulation leading to hyper or hypothermia. CC: Chills!

Erythroderma can be caused by 7 main causes
Papulosquamous
Dermatitis
Drug Rxn
CTCL
Infections
Auto-immune conditions
Physical causes
Back Extra: Papulosquamous: psoriasis, pityriasis rubra pilaris
Dermatitis: atopic, allergic contact, seborrheic, chronic actinic dermatitis, stasis derm
Drug Rxn: SJS, TEN, DRESS syndrome, drug rash
CTCL: erythrodermic MF, Sézary syndrome
Infections: Viral exanthems, Norwegian Scabies, Staph Scalded Skin syndrome
Auto-immune conditions such as Lupus, GVHD, bullous pemphigoid
Physical causes e.g. Burns

Q: Most common cause of erythroderma?
[...]
A: Psoriasis
Back Extra: Makes up 20% of cases, usually in pts who have a flare of pre-existing psoriasis
Caused by withdrawal of steroids/cyclosporine/methotrexate OR triggers (“SICK LAB” Smoking/Stress, Infections, Hypocalcemia, Koebnerization, Lithium, Antimalarial/ACE-I, BB...also alcohol, obesity, NSAIDs, terbinafine, TNF-alpha inhibitors)

Q: Erythroderma may have papulosquamous causes, including [...] and [...]
A: psoriasis; pityriasis rubra pilaris
Back Extra: Psoriasitic erythroderma caused by withdrawal of steroids/cyclosporine/methotrexate OR triggers (“SICK LAB”. Joint pain may be a key finding in psoriatic erythroderma; palmoplantar changes and weight loss also specific for psoriasis
Follicular plugging w/ islands of sparing on dorsal fingers and knees = pityriasis rubra pilaris

Erythroderma may be caused by dermatitis, including atopic dermatitis, allergic contact dermatitis, seborrheic dermatitis, chronic actinic dermatitis, and in very rare cases, stasis dermatitis with a profound id reaction
Back Extra: Severe pruritis may indicate atopic dermatitis (or Sézary syndrome)
Atopic Derm: hx of ≥1 features of atopic triad: atopic derm, hay fever, asthma. More severe itching. Look for ↑ IgE + eosinophilia on lab
Allergic Contact: (e.g. Parthenian plant in India)
Seborrheic: think of neurologic conditions (Parkinson’s) or HIV
Chronic Actinic: men >50 caused by UVA, UVB, and visible light. ↑CD8:CD4
Stasis derm with profound Id reaction: very rare cause of erythroderma

Erythroderma may be caused by atopic dermatitis, particularly if the patient exhibits signs of the atopic triad (atopic dermatitis, hay fever (allergic rhinitis), and asthma) or if they have eosinophilia and elevated IgE on labs
Back Extra: Severe pruritis may indicate atopic dermatitis (or Sézary syndrome)
Atopic Derm: hx of ≥1 features of atopic triad: atopic derm, hay fever, asthma. More severe itching. Look for ↑ IgE + eosinophilia on lab
Allergic Contact: (e.g. Parthenian plant in India)
Seborrheic: think of neurologic conditions (Parkinson’s) or HIV
Chronic Actinic: men >50 caused by UVA, UVB, and visible light. ↑CD8:CD4
Stasis derm with profound Id reaction: very rare cause of erythroderma

Q: Erythroderma may be caused by chronic actinic dermatitis, which is seen in men >50 caused by UVA, UVB, and visible light
Labs will show an ↑CD[...]:CD[...] ratio
A: 8; 4
Back Extra: Opposite of Sézary syndrome, which has an increased CD4:CD8 ratio
Actinic = referring to light, particularly UV light (think sun damage)

Erythroderma may be caused by drug reactions, including Stevens-Johnson syndrome, toxic epidermal necrolysis, and DRESS syndrome (also known as drug induced hypersensitivity reaction), and every day drug rashes
Back Extra: Allopurinol, bactrim, and anti-seizure medications are the most common culprits of both SJS and erythroderma
Those with HIV are more prone to get drug-induced erythroderma
DRESS = Drug Reaction with Eosinophila and Systemic Symptoms

Q: Erythroderma may be caused by cutaneous T-cell lymphomas, including [...] and [...]
A: Sézary syndrome; erythrodermic mycosis fungoides
Back Extra: Patients with Sézary syndrome are erythrodermic acutely, whereas erythrodermic MF patients get erythroderma from pre-existing plaques of MF and don't meet the criteria for Sézary syndrome

Q: What is the triad for Sézary syndrome?
[...], [...], and [...] in the skin, lymph nodes, and blood
A: Erythroderma; diffuse lymphadenopathy; malignant T-cells (Sezary cells)
Back Extra: Cerebriform or convoluted nuclei
Other features include alopecia, nail changes, and leonine faces

Differential for leonine facies?
Paget’s disease of the bone
Amyloidosis
Lepromatous Leprosy, Lymphoma, Leishmaniasis
Mycosis fungoides
Sarcoidosis, Scleromyxedema
Back Extra: “PALMS”

Q: Erythroderma with severe pruritis is most likely caused by [...] or [...]
A: atopic dermatitis; Sézary syndrome

Q: The [presence/absence] of a facial rash and the [presence/absence] of fever are helpful clues in ruling out psoriasis as the potential cause of erythroderma
A: presence; presence
Back Extra: Joint pain, depression, nail changes, and palmoplantar changes favor psoriasis as a potential etiology

Q: When evaluating the cause of erythroderma, violaceous rash is suggestive of [...], while a salmon rash is suggestive of [...]
A: CTCL; pityriasis rubra pilaris

Q: When evaluating the cause of erythroderma, facial edema may suggest [...] or [...] as the cause
A: a drug reaction; DRESS

Q: When evaluating the cause of erythroderma,a morbilliform rash may suggest [...] or [...] as the cause
A: a drug; viral rash

Q: Erythroderma may be caused by infection, including [...], [...], and [...]
A: viral exanthems; Norwegian Scabies; Staph Scalded Skin syndrome
Back Extra: May also consider doing a KOH scraping, as some patients have had an erythrodermic reaction from widespread dermatophyte infection

Q: [Fine/Large] areas of peeling in erythrodermic patients suggests an acute cause, such as a drug reaction, while [...] scale is more suggestive of atopic dermatitis or generalized tinea
A: Larger; fine

Q: What are the two forms of contact dermatitis?
[...] and [...] contact dermatitis
A: Irritant; allergic
Back Extra: Irritant contact dermatitis makes up 80% of contact dermatitis cases and can affect anyone with enough contact w/ substance and can occur in hours of contact since there is no need to recruit memory cells
Allergic contact dermatitis affects a small percentage of people that come into contact and requires time and re-sensitization, happening within a day or two

Q: What are the three ingredients in triple antibiotic ointments?
[...]
Which one(s) commonly cause allergic contact dermatitis?
[...]
A: “BNP”: bacitracin, neomycin, polymyxin B; Bacitracin and neomycin
Back Extra: Polymyxin is less common, but never say never!