90. Skin Disorders/Rash (23%) Flashcards
What’s the difference between Stevens-Johnson syndrome and Toxic epidermal necrolysis ?
- Stevens-Johnson syndrome (<10% skin involved)
- Toxic epidermal necrolysis (>30% skin involved)
Describe : Stevens-Johnson syndrome / Toxic epidermal necrolysis
- Rare immune-mediated skin reaction, usually triggered by medications
- Prodromal flu-like illness: Fever >39C, sore throat, rhinorrhea, cough, aches
- Sudden onset tender
- Painful skin rash on face/limbs
- 90% with involvement of mucous membranes (mouth, eyes, genital)
- Tender red/purple macules, diffuse erythema, targetoid lesions, bullae and/or vesicles (may have positive Nikolsky)
Describe tx : Stevens-Johnson syndrome / Toxic epidermal necrolysis
- Treat aggressively
- Treat underlying trigger
- Stop causative drug
- Treat infections (eg. Mycoplasma pneumoniae)
- Admission to ICU
- IV fluid resuscitation and wound management
Name common drugs that cause Stevens-Johnson sydrnome /TEN
- allopurinol
- NSAIDs
- antibiotics
- antiepileptics)
Name examples : Necrotizing soft tissue infections
- cellulite
- fasciite
- myosite
- gangrène gazeuse
Describe : Infections nécrosantes des tissus mous (3)
- Érythème diffus, gonflement, chaleur, brillance, sensibilité exquise
- Late findings : crépitation, bulles, nécrose cutanée, perte de sensation
- ↑ WBC, ↑ CRP/ESR, ↑ CK, subcutaneous air on XR/CT/MRI
Describe : Meningococcal infection (2)
- Can present with abnormal skin color pallor, mottling
- Petechial rash involving trunk, lower body, mucous membranes (oral and ocular), may have purpura, ecchymotic lesions
Describe tx : Infections nécrosantes des tissus mous (4)
- Admission en soins intensifs
- Exploration chirurgicale agressive
- Débridement
- Antibiotiques à large spectre : par exemple, Tazo/Clinda/Vanco IV
When to do Fluid Resuscitation for burns (children / adults)?
- > 15% BSA in children
- > 20% BSA in adults
Describe formula to determine fluid resuscitation for buns
Describe wound management in burns (6)
- Keep moist
- Apply antibiotic ointment to non-adherent dressing (Adaptic) then apply to wound
- Pain control
- Ensure tetanus vaccine status up-to-date
- Follow-up at <72h, to re-assess burn to better characterize partial vs. full thickness
- Refer to burn center PRN
Describe : Melanoma
- Subtype frequency: superficial spreading > nodular > lentigo maligna > acral lentiginous
- Diagnostic et traitement : biopsie excisionnelle pleine épaisseur avec marge de sécurité de 0,5 à 2 cm (selon l’épaisseur de Breslow)
Describe : Basal Cell Carcinoma
- Nodular BCC (most common) - raised pearly white nodule with telangiectasia >6mm
- Superficial BCC - red scaling plaques with thready border
- Diagnosis and treatment: full or partial-thickness biopsy (at edge of lesion to contain normal tissue)
- Excellent prognosis (low rates of malignancy)
Describe : Squamous Cell Carcinoma
- Persistent ulceration, crusting, hyperkeratosis, erythema
- Treatment: Surgical excision + biopsy (e.g., punch biopsy, Mohs micrographic)
- SCC In Situ: Bowen’s disease
Name Pre-malignancy lesions : Squamous Cell Carcinoma
Actinic keratosis (AK)
Leukoplakia (oral)
Lymphome T cutané (mycosis fongoïde )
- Infiltration lymphocytaire par étapes progressives (évolution lente au fil des années)
- Prurit → plaques ovales ou annulaires → plaque épaissie → tumeurs
Describe : Pemphigus (3)
- Désigne un groupe de maladies auto-immunes vésiculeuses et érosives potentiellement mortelles affectant la peau et les muqueuses
- Complications : une infection, une perte de liquide, des troubles électrolytiques
- Types: Vulgaris (le plus courant; 70% de tous les pemphigus), Foliaceus, IgA, Paranéoplasique
Describe tx : Pemphigus
- Stéroïdes systémiques (prednisone +/- rituximab)
- L’azathioprine ou le mycophénolate mofétil sont souvent utilisés pour tenter de réduire les stéroïdes
- Envisager un stéroïde topique d’appoint très puissant (par exemple, propionate de clobétasol) pour les érosions plus importantes.
- Couvrir les érosions avec une pommade antibiotique ou un émollient doux (par exemple, de la vaseline) +/- des pansements non adhésifs
Describe skin lesions : Granulomatose avec polyangéite (Wegener)
Purpura des membres inférieurs, nécrose focale et ulcérations (peuvent également inclure de l’urticaire, livedo reticularis, des nodules)
Describe : Systemic lupus erythematosus (SLE)
Acute
* Malar (or butterfly) rash that resolves without scarring
* Bullous, maculopapular, mucosal erosions/ulcerations, photosensitivity, hair loss
Subacute
* Flat scaly patches, annular polycyclic lesions on trunk and arms
Chronic
- Indurated hyperpigmented discoid plaques (most above neck)
Name skin lesions : Diabetes
- Acanthosis nigricans (seen in most patients with childhood diabetes)
- Diabetic dermopathy (30% of patients with diabetes) : Light brown/red oval/round scaly patches usually in pretibial area
Name skin lesions : Celiac
- Dermatite herpétiforme (« coeliaque de la peau »)
- Éruption papulovésiculaire prurigineuse sur les extenseurs
- Biopsie possible pour confirmer la maladie coeliaque
- Stomatite aphteuse récurrente
Describe : Kaposi’s Sarcoma
- Common in AIDS and following organ transplant
- Purple/black papular lesions, most commonly affecting lower limbs, back, face, mouth, genitalia
Describe tx : Dermatitis (3)
- 💡 Ensure proper general skin care
- Topical steroids (see table at bottom of page) applied sparingly BID x 2-4 weeks and re-assess
- Protopic for maintenance
Describe : Impetigo (2)
- Highly common contagious superficial bacterial infection (usually S. aureus or GAS)
- Primarily affecting children aged 2-5
Describe tx : Impetigo (6)
- Topical mupirocin 2% ointment (Bactroban) TID x 5 days
- Can consider topical fusidic acid (although some resistance)
- Extensive treatment (widespread dispersion, multiple lesions, and/or fever) : Systemic antibiotics
- Hand hygiene to prevent spread
- May return to school 24h after effective antibiotic therapy
- Draining lesions should be covered
Describe : Gale
- Highly contagious parasitic skin infection characterized by intense pruritus (particularly at night when mites are most active)
- Common in children, young adults, and people living in close proximity (e.g., child care facilities, nursing homes, prisons, refugee camps)
- Diagnosed clinically (e.g., close contact with confirmed positive, pathognomonic rash) or with dermoscopy
Describe lesions : Gale
- Lésions linéaires superficiels
- Petites papules excoriées au niveau des doigts, des poignets, des coudes, des aisselles, des aréoles, de la peau périombilicale, de la taille, des organes génitaux masculins, des genoux, des fesses et des pieds (lésion secondaire; images du milieu et de droite)
Describe tx : Gale
- Topical permethrin 5% cream applied to the whole body from the neck to the soles of the feet, including areas under the fingernails and toenails (plus scalp in infants & young children) and washed off after eight hours. Can be repeated 1 week later if necessary.
- Can manage pruritus with oral antihistamines or topical corticosteroids if severe
- All textiles, bedding, clothing should be washed and dried at hottest temperature
- Strongly consider prophylactic treatment for close contacts (even if asymptomatic as incubation period can be ~1 month)
- Watch for superficial bacterial infection and treat accordingly with oral antibiotics
