Peer Reviewed

What's Your Diagnosis?

Pustular Scab on an Elderly Woman's Head

Michelle L. Gallagher, DO1 • Casey Schukow, BS2 • Meghan Grossmann, BS2

  • AFFILIATIONS:

    1Department of Pediatrics, Michigan State University College of Osteopathic Medicine

    2Michigan State University College of Osteopathic Medicine

    CITATION:

    Gallagher ML, Schukow C, Grossmann M. Pustular scab on an elderly woman’s head. Consultant. Published online November 16, 2022. doi:10.25270/con.2022.11.000003

    DISCLOSURES:

    The authors report no relevant financial relationships.

    CORRESPONDENCE:

    Michelle L. Gallagher, DO, Michigan State University College of Osteopathic Medicine, 965 Wilson Road, East Lansing MI 48824 (docmlg@msu.edu)


    Abstract. An older adult presented to our clinic with chronic sun damage. She had history of several actinic keratoses, one of which was removed by electrodessication and curettage. This resulted in a plaque with pustular exudate and was diagnosed with erosive pustulosis of the scalp (EPDS). Our patient was treated with topical clobetasol. The patient was counseled on sun protection and the risks associated with chronic sun exposures.

    Key words: Dermatology, Erosive pustular dermatosis, Sun damage

     

    An 82-year-old woman presented to our clinic with a “pus-filled scab” on her scalp that had progressively enlarged over the past several weeks. The patient reported having a hypertrophic actinic keratosis around the scab that was removed by electrodessication and curettage about 1 month earlier. She reported a history of chronic sun exposure with inconsistent use of sun protective measures (eg, sunscreen) and actinic keratoses in other locations on her face and scalp treated with liquid nitrogen cryotherapy.

    Skin examination of her vertex scalp revealed a 1.6 cm by 1.3 cm ovoid plaque with pustular exudate and golden-brown crust on an erythematous base (Figure 1). Sparse hair around the plaque was seen. Approximately 2 inches anterior of the plaque was a scab from another hypertrophic actinic keratosis treated with electrodessication and curettage. No pus or erythema were noted within or around this scab.

    Figure 1

    Figure 1. An ovoid plaque with pustular exudate and golden-brown crust is seen on the patient’s vertex scalp.

    The patient described the plaque as mildly painful and itchy but denied any numbness, tingling, or constitutional symptoms (eg, fever, chills). Otherwise, she appeared well-nourished, alert, and oriented.

    What is the most likely diagnosis?

    1. Dissecting cellulitis
    2. Ecthyma
    3. Erosive pustular dermatosis
    4. Folliculitis decalvans
References
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