Actinic comedonal plaque in skin of color: A case report.

Actinic comedonal plaque is a variant of Favre-Racouchot syndrome which is a complication of solar degeneration of the skin. It is common in skin types 1-4 and unknown to rare in skin of color. This case report should create an awareness of this disease so not to be missed.

INTRODUCTION

Chronic actinic damage occurs mainly on sun‐exposed skin of fair‐skinned elderly people. It is characterized clinically by signs of photoaging, premalignant and malignant skin lesions. Favre‐Racouchot syndrome is a peculiar complication of solar (senile) degeneration of the skin manifesting with yellowish and atrophic skin, multiple, large, black comedones, follicular cysts, wrinkles and furrows, and yellowish nodules affecting mostly the temporo‐periorbital skin of elderly fair skinned individuals.1 It is associated with smoking and occurs most frequently in men. Actinic comedonal plaque is a rare variant of Favre‐Racouchot syndrome occurring on sun‐exposed ectopic sites.2 The published case reports have been on sun‐exposed skin of elderly fair individuals. We describe a Fitzpatrick skin type V‐V1 woman who smokes and presented with an actinic comedonal plaque on her left forearm.

CASE

We present the case of a 74‐year‐old dark‐skinned elderly woman, a smoker, with a 14‐year history of a hyperpigmented, painless, comedonal, plaque on the left forearm which would sometimes drain seropurulent fluid (Figure 1). She was otherwise well but was concerned about the possibility of skin cancer. A skin punch biopsy showed an unremarkable epidermis, solar elastosis, dermal fibrosis, perifollicular lymphocytic infiltrate, ruptured and keratin plugged hair follicles (Figures 2 and 3). A diagnosis of actinic comedonal plaque was made and the patient was put on tretinoin cream topically with minimal response. She was advised on the dangers of smoking.

Figure 1

Actinic comedonal plaque on forearm with comedones

Figure 2

Solar damage and fibrosis (Haematoxylin and eosin original magnification 10X)

Figure 3

Plugged hair follicle with lymphocytic infiltrate (Haematoxylin and eosin original magnification 10)

DISCUSSION

Favre‐Racouchot syndrome was first described in detail by Favre and Racouchot in 1937 and 1951. They described grouped comedones, nodular elastosis and cysts occurring on solar damaged skin of elderly individuals.1 Actinic comedonal plaque was first coined in 1980 by Eastern JS and Martin SA in a series of five elderly fair‐skinned individuals with lesions of confluent plaques, nodules and comedone‐like structures with a distinctive histologic picture of dilated keratin‐filled follicles within a matrix of amorphous damaged collagen.2 It is caused by actinic damage to the skin and is considered a variant of Favre‐Racouchot syndrome.

As with Favre‐Racouchot syndrome, exact pathogenesis remains obscure but extensive sun exposure is thought to be largely responsible. Heavy smoking3 and radiation therapy are other reported predisposing factors. The lesion must be distinguished clinically and histopathologically from comedonal nevus. However, a comedonal nevus is usually present at birth or appears during childhood.

All the reported actinic comedonal plaque cases encountered in the English literature were of fair‐skinned elderly individuals. The forearm was the predominant site as demonstrated by John and Hamm (1992) and Cardoso et al. (2015).4, 5 Cardoso et al. (2015) reported two cases, the second being a male smoker who also had the thorax involved. Pique‐Duran 2015, described actinic comedonal plaque on the nasolabial fold in an 82‐year‐old male who had previously had a basal cell carcinoma excised from the same area.6 Actinic comedonal plaque in a sun protected area has been described on the thigh of a 46‐year‐old fair skinned male. Males seem to be more affected than females. Smoking was only reported in one case. Our patient was different in the context of her skin color, but we still feel she otherwise fulfills the diagnosis of actinic comedonal plaque as evidenced by the cases discussed. Our patient was treated with topical tretinoin cream with little success. This case demonstrates that severe actinic damage occurs in all skin types and should be suspected always.

AUTHORSHIP

RMN: wrote and edited the manuscript, reported on the histopathology. DTN: provided the clinical diagnosis, medical care and drafted the manuscript.

CONFLICT OF INTEREST

None declared.