Pruritus can be a common complaint endorsed in both ambulatory and inpatient settings.

The best strategy for approaching pruritus is to stratify the pruritus into:

1. Pruritus related to an underlying skin condition
   • Skin is abnormal with evidence of inflammation
   • common primary skin disorders that may be associated with pruritus are indicated in the table below

     

2. Pruritus related to a systemic process
   • Skin is normal OR
   • The only skin abnormalities are related to chronic rubbing or scratching
     • Some clues:
       • Lichenification (thickened skin) or prurigo nodules (thickened, dark nodules)
       • Erosions in a linear pattern
       • Butterfly sign (sparing of the mid-back in a region that cannot be access for direct scratching)
   • 

When a secondary/systemic etiology is being considered, a comprehensive history and physical should be directed to evaluate for renal, liver, hematologic, endocrine, infectious, or autoimmune disease (as indicated in above table).

A basic series of investigations might include:

• CBC + Blood Film
• LDH, Uric acid, CXR +/- Flow cytometry of peripheral blood
• Creatinine and urea with electrolyte and extended electrolyte panel
• Liver enzymes, GGT, INR, Bilirubin, and bile acids along with hCG (age/gender-appropriate)
• TSH

Depending on the clinical history and examination, additional testing could include evaluation for connective tissue disorders as well as HIV and DM.

Principles of Pruritus Management:

1. Pruritus due to inflammatory skin disease: treat the inflammatory skin disease
2. Other general pruritus strategies include:
   • Nonpharmacologic: loose-fitting garments, moisturizer usage, reduced bathing, CBT/Biofeedback
   • Pharmacologic:
     • Topical: lidocaine, menthol, capsaicin
     • Systemic: Antihistamines, neuropathic agents (gabapentin, pregabalin)
     • Other: Phototherapy

Further Study:

• The American Academy of Dermatology offers a free, web-based Basic Dermatology curriculum consisting of multiple modules on high-yield, commonly encountered dermatology topics. Many of these are relevant for trainees of all backgrounds. Follow the link for more information: AAD Basic Dermatology Curriculum