Circle Hairs in a Patient with Multiple Myeloma

Introduction

Circle hair is a rare body-hair disorder characterized by the presence of hair rolled in perfect or nearly perfect concentric circles under a thin layer of stratum corneum without accompanying follicular hyperkeratosis or signs of inflammation.^1,2 The condition was first described by Adatto in 1963.² There are, to our knowledge, no reports of the association of circle hair with underlying dermatological or systemic diseases, and its pathomechanism remains unclear.^1,3 We present a case of circle hair in an 80-year-old woman with multiple myeloma who had skin lesions and abnormal hairs on both legs.

Case Presentation

An 80-year-old, bedridden woman with multiple comorbidities (ie, multiple myeloma being managed with palliative therapy; thalassemia; syndrome of inappropriate antidiuretic hormone; hypertension; and dyslipidemia) visited our institution with a 3-month history of slowly progressive skin lesions and abnormal hairs on her lower extremities. Her caregivers noticed these cutaneous abnormalities after the diagnosis of multiple myeloma. Her relatives were not aware of any trauma that the patient had experienced to the affected areas, and no family members had the same skin lesions. At the time of her visit, the patient had been using lorazepam, oxycodone, morphine, folic acid, sodium chloride, vitamin B complex, and lactulose for more than 3 years.

Physical examination revealed multiple brown scales with adherent centers and detached, outward-turning edges, with multiple, overlying, small black dots on the extensor areas of both lower extremities, sparing the flexural areas, as well as abnormal hairs on the areas of skin abnormality (Figure 1). Dermoscopic examination revealed multiple dark hairs with a perfectly circular arrangement, located under a thin layer of skin (Figure 2). The patient’s other systems were unremarkable. Histopathological examination revealed laminated hyperkeratosis with hypogranulosis, which was most compatible with ichthyosis. The specimen also contained a dilated hair follicle (Figure 3). Based on her clinical information and the dermoscopic and histopathological features, the patient was diagnosed with circle hair and acquired ichthyosis. The patient was treated with 10% urea cream, twice daily, and 10% lactic acid cream, once daily. The lesions had slightly improved by the 1-month follow-up visit.

Figure 1 Dermatological examination: (A) multiple brown scales with adherent centers and detached, outward-turning edges, with multiple, overlying, small black dots on the extensor areas of both lower extremities; (B) close-up view showing abnormal hairs on the areas of skin abnormality.

Figure 2 Dermoscopic examination: (A) multiple dark hairs with a perfectly circular arrangement, located under a thin layer of skin (original magnification x20); (B) close-up view of circle hairs (original magnification x80).

Figure 3 Histopathological examination: laminated hyperkeratosis with hypogranulosis and a dilated hair follicle.

Discussion

Circle hairs (or spiral hairs) are otherwise asymptomatic, dark hairs with a perfectly or nearly perfectly circular arrangement in the subcorneal layer of the skin, without any signs of inflammation.^1,4,5 They are most commonly noted in very hairy, overweight, middle-aged men in the range of 55–74 years old and can be surrounded by normal hairs.¹ The reported cases of circle hairs are scarce; however, this condition may be underdiagnosed owing to its asymptomatic nature. Common locations for circle hairs are the back, chest, abdomen, shoulders, thighs, and upper portions of the legs.^1,4 They are easily extracted by superficial scraping with a lancet, upon which they exhibit the characteristic question-mark shape and a typical length of 2–2.5 cm.¹

Dermoscopic examination of circle hairs reveals that their shafts are slightly smaller than those of normal hairs, and they coil into a distinctively circular configuration under the translucent stratum corneum.² Microscopic inspection reveals a narrowing hair shaft that forms a ring, with dystrophic anagen hair bulbs and the absence of an inner root sheath.² Typical histopathological findings include the presence of “river-bed,” dilated hair-follicle infundibula with entrapped hair shafts.² No follicular obstruction or perifollicular inflammation has been noted for this condition.⁴

The most important differential diagnosis of circle hairs are rolled hairs, which consist of symptomatic, irregularly twisted hair shafts that do not form a nearly perfectly circular arrangement and are located within hyperkeratotic papules, frequently present in the extensor regions of the extremities, shoulders, back, and buttocks.^4,6 Rolled hairs are reportedly linked to follicular hyperkeratosis and inflammation.^1,4 Many conditions are reportedly associated with rolled hairs, including palmoplantar keratoderma, keratosis pilaris, xerosis, and other dermatitis associated with chronic itching skin, as well as with the use of medications such as corticosteroids and cyclosporine.^1,7–10 Other hair disorders that resemble circle hairs, which may be included in the differential diagnosis, include pigtail hairs,^11–14 coiled hairs,^12,14,15 and corkscrew hairs.^12,16,17 Table 1 summarizes the clinical, dermoscopic, and histopathologic features of circle hair and its mimickers. The dermoscopic characteristics for our patient were compatible with circle hairs because of the hairs’ perfectly coiled nature, despite the absence of the characteristic river-bed appearance upon histopathology.

Table 1 Clinical, Dermoscopic, and Histopathologic Features of Circle Hair and Its Mimickers

The pathogenesis of circle hairs remains unknown, although there are two possible explanations. The first is that their thin diameter leads to an inability to penetrate the stratum corneum, resulting in their concentric circular growth. The other is that circle hairs are remnants of the mammalian undercoat.¹ There are no reported associations between circle hairs and medications or underlying diseases.^2,3 However, drugs that have the ability to promote hair growth, including corticosteroids, tacrolimus, and mycophenolate, may initiate this condition.³

Acquired ichthyosis is a nonhereditary cutaneous disease manifesting in adulthood as dry, rough skin with prominent scales.¹⁸ It commonly occurs on the trunk and extremities, especially on the extensor surfaces.¹⁸ The condition is associated with multiple diseases, eg, sarcoidosis, systemic lupus erythematosus, Hodgkin’s and non-Hodgkin’s lymphoma, leiomyosarcoma, Kaposi’s sarcoma, cutaneous T-cell lymphoma, and multiple myeloma.^18–24 None of the medications used by our patient have been reported to cause acquired ichthyosis.^2,3 Therefore, the etiology of the acquired ichthyosis in our patient is most likely multiple myeloma. In our case, the circle hairs may have occurred as a direct effect of multiple myeloma interfering with body-hair formation, resulting in thin and weak hair shafts.²⁵ Consequently, acquired ichthyosis may impede the penetration of hairs through the skin surface, entrapping them and causing them to grow in a circular pattern.

There is no specific treatment for circle hairs, and reassurance that it is not a harmful condition is sufficient.¹ We prescribed a topical humectant and keratolytic agent to moisten the skin and lessen the hair entrapment, which resulted in clinical improvement.

Conclusion

We report a case of co-occurrence of circle hairs and acquired ichthyosis in an older patient with underlying multiple myeloma. We also propose a possible mechanism of circle hairs and acquired ichthyosis occurring secondary to multiple myeloma. Circle hairs have the distinct feature of a perfectly coiled arrangement without perifollicular inflammation; however, physicians may be unaware of this disease owing to its rarity. As the pathogenesis of the disease is unknown, further studies are warranted.