Rosen & Barkin's 5-Minute Emergency Medicine Consult (580 page)

• Typical findings of erythema and scaling are the result of increased number of epidermal stem cells and keratinocyte hyperproliferation, shortened cell cycles, inflammatory infiltrates, and vascular changes
  
• Triggers include:
  
  • Drugs:
    
    • Lithium
      
    • β-blockers
      
    • Antimalarials
      
    • Steroid withdrawal
      
    • NSAIDs
      
    • Alcohol
      
    • Potassium iodide
      
  • Infections:
    
    • Streptococcal pharyngitis
      
    • HIV
      
    • Staph
      
  • Local trauma:
    
    • Frostbite
      
    • Sunburn
      
    • Recent skin trauma (Koebner phenomenon)
      
  • Stress: Emotional and physical
    
  • Winter:
    
    • Low light exposure
      
    • Dry weather
      
  • Cigarette smoking
    
  • Elevated BMI
    

DIAGNOSIS

• Long standing area of scaling erythema
  
• May give a history of previous diagnosis of psoriasis
  
• May be mildly pruritic
  
• May relate to one of the above triggers
  
• Specific location of lesions
  
• Family history of the disease
  
• History of improvement with sun exposure, or if recurrent, success of prior regimens
  
• Systemic symptoms like fevers or joint pains
  

• The classic skin lesion is a round, red patch with a central plaque of silvery, white scale that appears on extensor surfaces
  
• Redness and scaling around the umbilicus is highly suggestive of psoriasis
  
• Positive Auspitz sign:
  
  • Erythema and punctate bleeding when scales are removed
    
• In dark-skinned patients lesions may be grey
  
• Scalp lesions may be confused with seborrhea:
  
  • Lesions that extend beyond the hair borders indicate psoriasis
    
• Stippling and pitting of nail and onycholysis:
  
  • Yellow or brown band across the nail may help differentiate psoriasis (+ band) from onychomycosis (– band)
    
• Patients with plaque psoriasis may have concomitant psoriatic arthritis:
  
  • Often affects the DIP joints of the hands and feet
    
• Asymmetric oligoarticular arthritis:
  
  • Present in 70% of these patients
    
  • Swelling of the juxta-articular tissue
    
  • “Sausage-shape” to the affected digits
    

• The diagnosis is clinical
  
• Rarely, a biopsy is necessary to confirm the diagnosis or rule out other conditions
  

• No lab test confirms the diagnosis
  
• Elevated sedimentation rate in erythrodermic and pustular forms
  
• Positive streptococcal cultures and titers with guttate psoriasis
  
• Hypocalcemia and leukocytosis in pustular disease
  
• Negative rheumatoid factor
  
• Uric acid may be elevated
  
• If starting medications, consider checking baseline CBC, LFTs, and renal function, as well as TB screening
  

• Plain radiographs of the hands or feet may be abnormal with psoriatic arthritis
  
• Sacroiliitis and ankylosing spondylitis may also be seen on radiographs
  

Best thought of by region

• Scalp: Seborrhea
  
• Flexure creases:
  
  • Candidiasis
    
  • Intertrigo
    
  • Eczema
    
• Nails: Onychomycosis
  
• Trunk and extremities:
  
  • Nummular eczema
    
  • Pityriasis rosea or rubra pilaris
    
  • Tinea
    
  • Systemic lupus erythematosus
    
  • Syphilis
    
  • Lichen simplex chronicus
    
  • Atopy, drug eruption
    
  • Mycosis fungoides
    
  • Squamous cell carcinoma
    

TREATMENT

• Maintain universal precautions
  
• IV access and pain control as necessary
  

• General resuscitation efforts aimed at correcting fluid and electrolyte abnormalities
  
• Treating sepsis if present:
  
  • Cultures of lesions, blood, and urine
    
• Systemic steroids should not be used as they may predispose to severe complications
  

• Patients should be educated on the chronic nature of psoriasis and that there is no cure even with treatment
  
• Treatments can be expensive and compliance is often poor
  
• Some patients may decline treatment in milder cases
  
• 3 basic types of treatment for psoriasis:
  
  • Topical therapy
    
  • Systemic therapy
    
  • Phototherapy
    
• Topical therapy is the most commonly prescribed treatment modality from the ED
  
• Systemic therapy is usually employed only after failure of topical and phototherapy and in conjunction with a dermatologist
  
• Exceptions where systemic therapy may be used:
  
  • Generalized pustular psoriasis
    
  • Very active psoriatic arthritis
    
  • Psoriasis that is considered severely disabling
    
• Phototherapy is not an ED treatment modality
  
• Dermatology consult should be obtained in severe cases
  

• Mild to moderate disease:
  
  • Usually topical treatment only
    
  • No single topical agent works best for all patients.
    
  • Emollients:
    
    • Works well for limited plaque psoriasis
      
    • Greasier choices work best, but may be poorly tolerated by patients.
      
  • Topical steroids
    
    • Major form of therapy for those with limited disease
      
    • Can be used as monotherapy, 1–2 times a day, or in combination with emollients
      
    • Once improvement is achieved, consider tapering use
      
    • May need to rotate drugs
      
    • Occlusive dressing improves efficacy
      
  • Salicylic acid
    
    • Topical keratolytic agent
      
    • Precaution if already on systemic aspirin
      
  • Coal-tar preparations:
    
    • Usually used with topical steroids
      
    • Newer forms are less messy
      
  • Vitamin D analogs:
    
    • Calcipotriene and calcitriol
      
  • Tazarotene
    
    • Topical retinoid, 0.1% cream
      
    • Pregnancy class X
      
  • Tacrolimus
    
    • Topical treatment for inverse psoriasis or facial lesions
      
• Is steroid sparing and reduces risk of atrophy from steroids
  
• Moderate to severe disease:
  
  • The above-named agents may be employed along with phototherapy and systemic medications
    
  • Phototherapy:
    
    • UV radiation is thought to have antiproliferative and anti-inflammatory effects
      
    • Ultraviolet B light is usually combined with ≥1 topical agents and has reports of 80% remission
      
    • Ultraviolet B may be used alone in guttate psoriasis
      
    • Psoralen ultraviolet A (PUVA) light therapy combines a systemic agent (psoralen) that sensitizes the skin to UVA light
      
    • Therapy is usually given 2–3 times per week
      
  • Systemic agents: May be used in various combinations with the above modalities:
    
    • Should not be initiated without dermatology consultation
      
    • Methotrexate (immunosuppressant): Assess renal, liver, and hematologic function prior to therapy; not to be used during pregnancy
      
    • Retinoids: May cause dryness, scaling, redness, and tenderness of the skin
      
    • Systemic corticosteroids: Not favorable due to iatrogenic Cushing syndrome; it may have a role in acute erythrodermic psoriasis if patient is extremely ill
      
    • Cyclosporine: Use in conjunction with dermatology consult
      
  • Injectable immunosuppressants: Etanercept and Alefacept
    

FOLLOW-UP

• Advise patients that the disease is not contagious
  
• Warn patients to avoid skin trauma and sunburns
  
• Educate the patient on avoiding medications that trigger relapses
  
• Refer patients to the National Psoriasis Foundation,
  www.psoriasis.org
  

• About 10–15% of cases occur ≤age 10
  
• Involvement of face and flexural areas more common; pustular and erythrodermic less common
  
• May have significant psychosocial impact on this population
  

Many of the drugs used to treat psoriasis are contraindicated in pregnancy

• Referral to dermatology is indicated for most patients with psoriasis
  
• Patients with psoriasis may also need referral to primary care doctor and/or psychiatry to cope with impaired quality of life
  

Follow-up with dermatology and/or primary care doctor to evaluate efficacy of treatment

• Patients with pustular psoriasis are at risk for severe systemic infections
  
• Patients with erythrodermic psoriasis are at risk for dehydration and may need to be treated similarly to a major burn patient
  
• Improvement occurs in weeks, not days