M25.561 - Pain in right knee

Clinical Definition

Small, mobile, elevated lesions on the skin surface containing clear fluid (serum) measuring less than 0.5 cm in diameter. A vesicle is essentially a small blister filled with serous fluid that develops between layers of the epidermis.

Documentation Requirements

• Size: Must specify lesion is less than 0.5 cm (larger would be classified as a bulla)

• Content: Document that fluid is clear/serous (not blood, pus)

• Location: Specific anatomical site(s)

• Number: Single vs multiple vesicles

• Cause/Etiology: Document if known:

  • Viral (e.g., herpes, chickenpox)

  • Contact dermatitis

  • Friction/thermal

  • Autoimmune conditions

• Timing: Acute vs chronic presentation

Common Synonyms

• Small blister

• Water blister

• Fluid-filled bump

• "Fever blister" (in case of herpes)

• Water bubble on skin

Coding Conflicts

Excludes1:

• Bullae (>0.5 cm)

• Pustules (containing pus)

• Epidermal cysts

Excludes2:

• Vesicular rash due to viral infection

• Contact dermatitis with vesicles

Scribing.io Automation

Our AI scribe automatically:

• Detects descriptive terms like "small," "clear fluid-filled," "blister"

• Measures mentioned size to differentiate from bullae

• Maps anatomical locations

• Tags causative factors when documented

• Links to associated conditions (e.g., "HSV with vesicles")

• Alerts if documentation is insufficient for specificity