What Is Fox Fordyce Disease?
Fox-Fordyce disease is an uncommon inflammatory condition affecting the apocrine glands of the skin. The condition is also known as apocrine malaria or apocrine duct occlusion. Fox-Fordyce disease was first described by George Henry Fox and John Addison Fordyce in the year 1906. The apocrine sweat gland abnormalities of Fox-Fordyce disease results in inflammation, gland enlargement, and itching of the affected area. Fox-Fordyce disease presents with pruritic papular eruptions in the areas of the body where apocrine glands are abundant; for example, underarms, pubic region, and the area around the nipples. Fox-Fordyce disease is more prevalent among women as compared to men. The skin around the affected area may darken, dry, and produce numerous papules or little raised bumps. Moreover, hair loss may occur in the affected area due to secondary hair follicle damage.
What Causes Fox Fordyce Disease?
The exact cause of Fox-Fordyce disease is unknown, and studies are being done to determine it. Though studies have not conclusively proven it, researchers have hypothesized that blocking the apocrine gland ducts is the primary cause of Fox-Fordyce disease. According to this theory, the apocrine gland duct becoming blocked because of keratin buildup in the follicular infundibulum appears to be the leading cause of the condition. Experts further suggest that in the areas where the duct is close to the hair follicle, blocked ducts break and cause inflammation. Moreover, factors that may be responsible for the development of Fox-Fordyce disease are:
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Familial Inheritance: Although Fox-Fordyce disease primarily occurs randomly, it can very rarely affect sisters, monozygotic females, male twins, and father-daughter pairs.
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Hormonal Factors: Fox-Fordyce disease is prevalent in post-pubertal adolescent girls and women. The condition is rarely reported in prepubertal and post-menopausal women and men. Premenstrual flare-ups and improvements with pregnancy, post-menopause and oral contraceptives lend more support to hormonal involvement.
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Laser Hair Reduction: There are theories that the follicular infundibulum is damaged by laser irradiation, which is followed by keratin plugs.
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Other Trigger Factors for Itch: Other factors that may trigger intense itching in an individual are stress, sweat, exercising, hot or humid weather, etc.
What Are the Symptoms of Fox Fordyce Disease?
The signs and symptoms of Fox-Fordyce disease are:
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The symptoms may present suddenly after conditions involving heat, humidity, and friction.
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There is an eruption of numerous small bumps (papules) that appear to be raised on the skin and present near the apocrine glands.
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The papules are often skin-colored but can sometimes be yellowish or reddish. Moreover, these papules are smooth and dome-shaped.
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These papules are typically 2 mm (millimeter) to 3 mm in size.
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Hypotrichosis (a condition characterized by the sparsity of hair), hyperkeratosis (thickening of the skin’s outer layer, which constitutes keratin), and scratch-related excoriation (skin-picking) marks may also be seen as associated symptoms.
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Papules are primarily seen in the armpits, pubic area, and the area around the nipples.
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The affected areas are extremely itchy (pruritus).
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The pruritus may worsen in humidity, sweating, stress, excitement, etc.
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Hair follicles in the affected area may show hair loss.
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Fox-Fordyce disease may progress as relapse and remission and may continue for years. However, the condition may improve after the glands of the affected areas get damaged.
Who Is Affected by Fox Fordyce Disease?
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Fox-Fordyce disease primarily affects females between the ages of 13 and 35.
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In rare cases, men, kids, and post-menopausal women can also be affected.
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According to some statistics, the ratio of affected women to men is 9:1.
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The exact incidence rate of the disease is unknown because the disease is sporadic, and there are not enough reported cases.
How Is Fox Fordyce Disease Diagnosed?
Fox-Fordyce disease is diagnosed in the following ways:
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Clinical Evaluation: Fox-Fordyce disease is primarily diagnosed clinically. Identifying distinctive symptoms, a thorough review of the patient's medical history, and a careful clinical assessment contribute to the diagnosis.
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Dermoscopy: Dermoscopy is a noninvasive diagnostic modality that uses a dermatoscope to examine and evaluate skin lesions and conditions. Dermoscopy in the case of Fox-Fordyce disease displays blackheads, damaged terminal hairs, and hair follicle-centered papules.
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Biopsy: A diagnosis may be made through surgical excision and microscopic examination (biopsy) of the afflicted tissue. A biopsy of the papules may be done.
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High-Definition Optical Coherence Tomography (HD-OCT): This test may show epidermal (skin’s outer layer) lesions extending into the skin's upper layer (dermis).
How Is Fox Fordyce Disease Treated?
Fox-Fordyce disease is usually treated symptomatically, and the treatment is specific for each patient depending upon their symptoms and their severity. A dermatologist consultation is advised. The usage of specific treatments has included topical antibiotics, oral retinoids, steroid creams, and estrogen therapy. No single treatment modality is consistently successful in all patients. Moreover, the lines of treatment for Fox-Fordyce disease include:
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First Line of Treatment: Intralesional or topical corticosteroids, topical Calcineurin inhibitors, topical and oral retinoids, topical Benzoyl-peroxide, topical Clindamycin, and oral contraceptives are among the first-line treatments. These are the first options due to their accessibility, ease of administration, and lack of major side effects. However, Fox-Fordyce disease may recur once these treatments are stopped.
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Second Line of Treatment: These are more effective for cases that are severe or resistant to first-line treatments. The treatment modalities of the second line include surgical removal, fractional lasers, pulsed dye laser, phototherapy, etc.
What Are the Complications of Fox Fordyce Disease?
Complications of untreated and long-term Fox-Fordyce disease are:
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Chronic Fox-Fordyce disease may manifest as thicker, coarse, or hyperpigmented skin as a result of scratch-related damage.
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Due to the eventual loss of the gland and associated hair follicles, severe Fox-Fordyce disease may also show localized anhidrosis (a condition where the sweat glands do not secrete sweat) and brittle, sparse, or missing hair.
Conclusion:
Fox-Fordyce disease is a rare inflammatory condition affecting the apocrine glands. The condition is characterized by itching and the appearance of papules on the surface of the affected skin areas. The diagnosis of the condition is mainly based on clinical evaluation, and the treatment modalities also depend upon the patient’s specific symptoms and the severity of the disease. Fox-Fordyce disease has no definitive cure, but therapy approaches have been shown to improve symptoms to full recovery. The prognosis is, therefore, generally favorable.
