SM

Primary Skin Lesions

Chapter 20: Health History and Physical Assessment

Table 20.2: Primary Skin Lesions

Macule/Patch

  • Description:
    • A flat lesion that is not detectable through palpation.
    • Characterized by changes in color.
  • Examples:
    • Port wine stain
    • Flat moles
  • Size Specification:
    • Size < 1 cm: referred to as a macule
    • Size > 1 cm: referred to as a patch

Papule/Plaque

  • Description:
    • Solid, raised lesions with distinct borders.
    • Can take a variety of shapes including domed, flat-topped, and umbilicated.
    • Often associated with secondary features such as crusts or scales.
  • Examples:
    • Wart
    • Psoriasis
    • Actinic keratosis
  • Size Specification:
    • Size < 0.5 cm: referred to as a papule
    • Size > 0.5 cm: referred to as a plaque

Nodule

  • Description:
    • A raised solid mass that has defined borders.
    • Extends into the dermis or beyond.
    • Deeper and more solid than a papule.
  • Size Specification:
    • Size ranges from 0.5 cm to 2 cm.
  • Examples:
    • Lipomas
    • Squamous cell cancers

Tumor

  • Description:
    • A solid mass that extends through the subcutaneous tissue.
    • May have undefined borders and is not always cancerous.
    • Can include larger lipomas, which are tumors typically > 1-2 cm.
  • Examples:
    • Cancerous lesions

Vesicle/Bulla

  • Description:
    • Circumscribed, raised lesions filled with serous (clear) fluid.
  • Size Specification:
    • Size < 0.5 cm: referred to as a vesicle
    • Size > 0.5 cm: referred to as a bulla
  • Examples:
    • Chickenpox (varicella)
    • Poison ivy
    • Second-degree burn blisters

Pustule

  • Description:
    • Similar to vesicles but contains pus instead of clear fluid.
    • Circumscribed, elevated lesion.
    • Most commonly found in infected areas.
  • Examples:
    • Impetigo
    • Acne

Wheal

  • Description:
    • An irregularly shaped area of edema caused by serous fluid in the dermis.
    • Varies in color and size.
  • Examples:
    • Hives (urticaria)
    • Insect bites

Burrow

  • Description:
    • Appears linear or circular.
    • Caused by the infestation and tunneling of parasitic organisms.

Cyst

  • Description:
    • Encapsulated fluid-filled or semisolid mass that extends into the dermis or subcutaneous tissue.
  • Examples:
    • Scabies mites
    • Ringworms
    • Sebaceous cyst

References

  • Habif, T. P. (2016). Clinical dermatology (6th ed.). St. Louis, MO: Mosby.
  • Weston, W. L., Lane, A. T., & Morelli, J. G. (2016). Textbook of pediatric dermatology (4th ed.). St. Louis, MO: Mosby.
  • Goldman, M. P., & Fitzpatrick, R. E. (1994). Cutaneous laser surgery. St. Louis, MO: Mosby.
  • Lemmi, F. O., & Lemmi, C. A. E. (2000). Physical assessment findings CD-ROM. Philadelphia, PA: Saunders.
  • Wood, M. J., Innes, J. A., et al. (1992). Infectious diseases (2nd ed.). London: Gower.
  • Marks, J. G., & Miller, J. J. (2019). Lookingbill and Marks' dermatology (6th ed.). St. Louis, MO: Elsevier.