Peer Reviewed

Photo Quiz

What Are These Brown Plaques on This 16-Year-Old Girl’s Back?

Meghan C. Grossmann, BSc1 • Michelle L. Gallagher, DO2

    1Medical Student, Michigan State University College of Osteopathic Medicine, Detroit, MI
    2Assistant Professor, Department of Pediatrics, Michigan State University College of Osteopathic Medicine, East Lansing, MI

    Grossmann MC, Gallagher ML. What are these brown plaques on this 16-year-old girl’s back? Consultant. 2023;63(5):e3. doi:10.25270/con.2022.07.00001

    Received December 1, 2021. Accepted January 4, 2022. Published online July 5, 2022.

    The authors report no relevant financial relationships. The authors report that informed patient consent was obtained for publication of the images used herein.

    Meghan C. Grossmann, BSc, Michigan State University College of Osteopathic Medicine, 965 Wilson Road, East Lansing, MI 48824 (


    A 16-year-old girl presented to our clinic with a 5-month history of hyperpigmented brown plaques on her back. The plaques had enlarged over time and worsened over the last few months. She reported the areas to be nonpruritic and nonpainful. Her medical history was not remarkable, and she was not taking any medications at the time. Her body mass index (BMI) was within the normal range. As shown in Figures 1 and 2, the plaques appeared in the middle region of her back extending down the side of her spine. The plaques were not found anywhere else on the patient's body.

    Figure 1
    Figure 1. Hyperpigmented plaques on our patient prior to treatment.

    Figure 2Figure 2. Our patient post-treatment with isopropyl alcohol.


    What is causing this patient's plaques?

    A. Acanthosis nigricans
    B. Becker nevus syndrome
    C. Confluent and reticulated papillomatosis
    D. Lichen planus
    E. Terra firma-forme dermatosis

    Answer and discussion on next page.