Clinical and Dermoscopic Image of Hairs Trapped in the Acne Scar: Is It Ingrown or Circle Hairs?

A 35-year-old male presented with an asymptomatic hyperpigmented papulonodular lesion over the left cheek for 3 months. There was a history of acne before 6 months. He took some treatment and did not go for shaving of beard hairs for 1 month before the development of present lesion with the fear of getting trauma and bleeding of lesions. On examination, a single 3–4 mm nodule over the left cheek forming a track of acne scar with whorls of hairs trapped in it [Figure 1a and b]. Dermoscopy with the FireflyPro DE 300 showed 10–15 whorls of hairs entrapped underneath the two acne scars joint by a normal skin [Figure 2]. Extracted hairs from the scar by a forceps [Figure 3] were rolled out, but recoiled.

Figure 1

(a) Single 3–4 mm nodule over left cheek forming a track of acne scar with whorls of hairs. (b) Whorls of hairs entangled in acne scar

Figure 2

Dermatoscopy showing 10–15 whorls of hairs entrapped underneath acne scars joint by a normal skin

Figure 3

Extracted recoiled hairs from the scar

Circle hairs (CHs) are characterized by asymptomatic presence of hairs with typical circular or spiraliform arrangement, not associated with follicular or inflammatory abnormalities.[1] When facial hair grows, it tends to bend back instead of continuing outward and upward. Once it bends back, the sharp edge of the facial hair simply pierces the skin and continues growing under it. CH has a small hair diameter that makes it difficult to penetrate stratum corneum and thus growing in a circular track with subcorneal location. It can be due to follicular ostia which are continuously open and hence the hair does not need to perforate the stratum corneum.

Ingrown hairs developing over the face can be due to dead skin cells, shaving too closely, pulling the skin, bacterial or fungal infection, chemicals that irritate skin, pore-clogging skin care products, dirt, makeup, and grease. The skin that lacks moisture is more prone to developing ingrown hairs because it can weaken the skin's natural healing and defense mechanism.[2] Anyone can get an ingrown hair. However, the problem is more common in people who have very curly or coarse hair. Curly hair is more likely to bend back and re-enter your skin, especially after it has been shaved or cut. The hair that grows back has a sharper edge, so it can more easily poke back through your skin and get trapped under the surface.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.