Acanthoma Fissuratum

AUTHORS:
Norhan Shamloul, BS
Drexel University College of Medicine, Philadelphia, Pennsylvania

Ronald F. Maceyko, MD
Allegheny Health Network Dermatology, Pittsburgh, Pennsylvania

CITATION:
Shamloul N, Maceyko RF. Acanthoma fissuratum [published online December 17, 2019]. Consultant360.

We report two unusual cases of acanthoma fissuratum (AF), one occurring within the concha and resulting from newer-generation hearing aids, and the other on the bridge of the nose due to the use of a continuous positive airway pressure (CPAP) device.

CASE 1

A 77-year-old man with a history of hearing loss presented to the clinic with a chief concern of a lesion on the right ear that had been present for 2 weeks. He had been referred by his primary care physician to rule out cutaneous malignancy. The patient had been wearing hearing aids for many years, with the current half-shell set having been used for the past 2 years. He stated that the lesion was irritated by his hearing aid.

On examination, a 5-mm, well-defined, erythematous, slightly edematous coffee bean–shaped papule involving the right conchal bowl and just lateral to the external auditory meatus was noted (Figure 1). Exactly one-half of this lesion was covered by his hearing aid (Figure 2).

Figure 1. A coffee bean–shaped papule on the right conchal bowl.

Figure 2. Hearing aid covering exactly one-half of the lesion.

Dermoscopic examination of the lesion revealed neither arborizing telangiectasia nor asymmetry of color or structure. The lesion was determined to be inflammatory in nature and was treated with intralesional triamcinolone acetonide injection, 0.5 mg.

Follow-up examination 2 weeks later revealed the same lesion (now measuring 6 mm) conforming to the area where the hearing aid abutted the skin. A clinical diagnosis of AF was established, and the patient was advised to discontinue the use of the hearing aid in the right ear to potentially avoid the need for a skin biopsy.

Follow-up examination of the right concha 4 weeks later revealed that the lesion had resolved completely (Figure 3). He was advised to have his hearing aids adjusted so they would fit better. He switched to a different set of hearing aids, after which he was free of any lesions or discomfort of the right concha.

Figure 3. Complete resolution of AF 4 weeks after discontinuation of wearing the previous hearing aid

Interestingly, the patient returned to the clinic 13 months later with similar concerns, but this time of the bilateral ears. He had recently switched to new hearing aids with a plastic ear hook. Examination of each ear revealed a focal erythematous depression with surrounding mild edema of the conchal bowl where the monofilament ear hooks of the hearing aid contacted the skin (Figure 4). The stabilizer ear hook portion was displaced from the concha bowl, which provided immediate relief. Once again, he was advised to have his audiologist adjust the fit of the hearing aid, this time decreasing the length of the ear hook and ensuring the end was smooth, gently tapered, and not needlelike.

Figure 4. Early AF developing from a monofilament ear hook irritating the skin.

CASE 2

A 58-year-old man with a history of psoriasis, psoriatic arthritis, chronic obstructive pulmonary disease, and obstructive sleep apnea presented with a 1-week history of a painful lesion on the bridge of the nose. He had been wearing a CPAP mask during sleep for 3 years.

Physical examination revealed a 7-mm, firm, tender, erythematous, centrally superficially ulcerated nodule with peripheral erythema (Figure 5).

Figure 5. A lesion on the of bridge of the nose at the site of contact with a CPAP mask.

The patient preferred to have a diagnosis established with certainty as soon as possible, so a biopsy was performed to rule out malignancy. Histologic sections of the specimen demonstrated irregular epidermal acanthosis with localized scale crust present, peripheral to a central ulcer, beneath which there was a dense, suppurative infiltrate. These histologic findings, along with the clinical picture, suggested that the lesion was ulcerated AF secondary to the patient’s use of a CPAP device.

The patient was reassured about the benign nature of the lesion and was encouraged to see his respiratory therapist for adjustments to his mask. He did so, and the lesion resolved.