Pseudofolliculitis corporis: a new entity diagnosed by dermoscopy.

Pseudofolliculitis mainly affects the beard area, but it can occur in any area of hair-bearing skin when traumatic methods like shaving or plucking are used to remove the hair. It can be a simple cosmetic problem or a disturbing medical condition for which the dermatologist must be prepared. It can develop in areas of shaving or depilation and has been seen in the pubic region or the axilla, where it is common to find curly hair that emerges at an acute angle. Here, we are reporting a case of pseudofolliculitis over back, termed as pseudofolliculitis corporis. He used to put a pillow behind the back while driving and the pressure caused the pseudofolliculitis. The diagnosis was confirmed by dermoscopy, which is a simple office procedure. Patient was advised to stop using the pillow and improved with topical adapalene and clindamycin gel for 15 days. This entity has not been described in the literature.

INTRODUCTION

Pseudofolliculitis is an inflammatory disorder that occurs most frequently in men with a dense and curly beard. Pseudofolliculitis barbae occurs when emerged terminal hairs, particularly the thick, curly hairs of the beard, grow back towards the surface.[12] It can be a simple cosmetic problem or a disturbing medical condition for which the dermatologist must be prepared. The submandibular area is most frequently affected due to the higher hair density and the oblique direction of hair growth in this area. Pseudofolliculitis is not confined to the beard area of the face. It can develop in areas of shaving or depilation and has been seen in the pubic region or the axillas, where it is common to find curly hair that emerges at an acute angle.[3] In individuals with very curly body hair, pseudofolliculitis can also occur after depilation of other areas such as the chest, back, or legs.[4]

CASE REPORT

A 32-year-old male presented with mildly pruritic lesions over back since 3 years [Figure 1]. Previously he was diagnosed as truncal acne and treated with oral isotretinoin and multiple courses of antibiotics. There was partial improvement, but lesions were reappearing in few weeks. He was a driver by occupation. On clinical examinations, there were follicular papules over mid portion of the back. On dermoscopy, the hairs were seen like loops [Figure 2a] and some of the lesions were solid papules [Figure 2b]. Few of the lesions were removed with a curette and examined on a piece of paper under dermoscope. Hairs coming out of the skin and again reentering in few lesions [Figure 3a] and the solid papules had bend hairs inside [Figure 3b]. The diagnosis of pseudofolliculitis corporis was made. On further questioning, he revealed that he used to put a pillow in the mid portion of his back while driving. He was explained of the fact that the lesions were due to the chronic friction and advised to stop that practice. He was advised adapalene and clindamycin combination gel for 15 days. On follow-up at 6 months and 1-year there was no recurrence.

Figure 1

Pruritic follicular papules over back

Figure 2

(a) On dermoscopy the hairs were seen like loops. (b) Solid papules over back seen on dermoscopy

Figure 3

(a) Hairs coming out of the skin and again re-entering. (b) Solid papules had bend hairs inside

DISCUSSION

Pseudofolliculitis mainly affects the beard area, but it can occur in any area of hair-bearing skin when traumatic methods like shaving or plucking are used to remove the hair.[5] The sharp ends of the hairs left by the oblique cut of the razor make contact with the epidermis at an angle of 90° and on penetration to the epidermis looks like a hair follicle, referred to as a pseudofollicle. A very close shave may also cause the hair to pierce the epidermis before reaching the surface. Shaving against the grain while tensing the skin and on releasing the tension, the hair is drawn back below the skin surface may pierce the epidermis before reaching the surface leading to pseudofolliculitis. This phenomenon is less likely to occur with finer, less curved hairs or when the angle at which the hair is cut during shaving is perpendicular to the skin.

If a person with pseudofolliculitis stops shaving, hair growth to a length of 10 mm usually pulls the hair out of the inflammatory papule, and the process tends to resolve spontaneously.[6] A recent study found a A12T polymorphism of the gene coding for keratin K6hf, found in a thin layer of cells between the inner and outer sheaths of the root of the hair follicle gives rise to a six-fold increase in the risk of suffering pseudofolliculitis barbae.[7] Abnormalities in this keratin constitute a risk factor for pseudofolliculitis, and when thick wavy or curly hair is involved, hair ingrowth after shaving is more likely.[78] Another study has demonstrated that curly hair and the presence of whorls increase the risk of developing pseudofolliculitis barbae by more than 50%.[9] Pseudofolliculitis has been reported in the nose, caused by plucking the stiff nasal hairs or cutting them with scissors very close to the surface of the skin. The condition may also occur after preoperative shaving. Pseudofolliculitis can also be related to certain occupations in which the subject has to maintain a device or hard surface against the cheek for long periods of time. A classic case is “fiddler's neck,” a form of pseudofolliculitis barbae caused by the pressure of the violin under the mandible.[1011] Other causes of occupational pseudofolliculitis include the use of constricting objects, devices, or clothing that rub on hair-bearing areas and produce depilation by friction. There have also been reports of cases related to the administration of medicines that can favor the acne, such as corticosteroids and ciclosporin.[12]

The diagnosis of pseudofolliculitis barbae is based on clinical characteristics. Dermoscopy can be used to confirm the diagnosis.[13] In our case, we used dermoscopy for visualization of in growing hairs. Curetting the papule and putting the tissue over a white paper and again examining under dermoscope will give the diagnosis. As this is an office based procedure, can be done in any sitting and invasive procedures like biopsy can be avoided.

The aim of treatment is to reduce extrafollicular and transfollicular hair penetration and to reduce chronic inflammation. Avoidance of the cause is most important as our case improved due to the simple advice (stopped using pillow behind back while driving). It is advisable to stop shaving for around 4 weeks and attempts can be made to remove the ingrown hairs by freeing them with a sterile needle. When these methods are insufficient, or the inflammation becomes severe, medical treatment is required.[14] The only published randomized clinical trial included 88 men who were treated with a gel containing 5% benzoyl peroxide plus 1% clindamycin or a placebo gel for 10 weeks.[15]

Pseudofolliculitis corporis over back has not been described in the literature. Though driving with a pillow behind the back is very common, this entity is less recognized. High index of suspicion, simple investigations like dermoscopy will give the diagnosis. Once confirmed, avoidance of pressure factor and topical treatment will give cure to the patient.