BASICS
DESCRIPTION
A rare chronic pruritic skin condition involving apocrine glands. Named for the physicians who first described it (1); also known as apocrine duct occlusion or apocrine miliaria; caused by destruction of follicular infundibulum with keratin debris
EPIDEMIOLOGY
Incidence
A rare condition without geographic, ethnic, or racial predilection. Approximately 90% of patients are women between the ages of 13 and 35 years. Ten times more common to occur in women than men. Incidence of the disorder is unknown.
ETIOLOGY AND PATHOPHYSIOLOGY
- A defect in the follicular infundibulum causes follicular dilation with keratin plugging. This results in apocrine duct obstruction, rupture, and inflammation (2,3), which causes extravasation of the apocrine secretions.
- Although blockage of the apocrine duct seems important in disease development, experimentally plugging the duct has not clinically reproduced disease manifestations.
- Unknown/possibly endocrine related.
Genetics
- The genetics of Fox-Fordyce are unknown but likely play in role. There have been reports of the disease occurring in identical male twins, one set of siblings, in a father and daughter, in two patients with Turner syndrome, and in one patient with a small deletion on chromosome 21.
- Hormones
- The role of hormones in Fox-Fordyce has been largely debated (1); disease onset after puberty and improvement with pregnancy and estrogens lends support to a hormonal influence.
- However, hormonal studies in one patient with Fox-Fordyce did not reveal any abnormalities.
COMMONLY ASSOCIATED CONDITIONS
- Possibly related to hyperhidrosis
- Hidradenitis suppurativa (rare)
DIAGNOSIS
HISTORY
- The development of pruritic papules at the time of puberty with gradual worsening.
- Patient will complain of extreme pruritus.
- Heat, humidity, sweating, and stress exacerbate symptoms.
PHYSICAL EXAM
Lesion characteristics:
- Location:
- Intertriginous and apocrine-rich areas are affected.
- Axillae, pubis area (labia majora, mons pubis), perineum, chest, breast, areola, and upper thighs
- Description:
- Numerous symmetrically distributed skin-colored to slightly yellow or red follicular, dome-shaped papules that are equidistant from one another and characteristically intensely pruritic. (1).
- Additional findings:
- Lichenification secondary to pruritus and excoriations
- Resemble lichen planus, lichen nitidus, folliculitis, or syringomas (4)
DIFFERENTIAL DIAGNOSIS
- Lichen planus; lichen nitidus
- Lichen simplex chronicus; lichen amyloidosis
- Folliculitis
- Multiple syringomas
- Adnexal tumor
- Darier disease
- Intertrigo
- Flat warts
- Follicular eczema; folliculitis
- Molluscum contagiosum
- Spongiotic dermatitis
- Trichostasis spinulosa
- Acanthosis nigricans
- Syringomas candidiasis
- Epidermal nevus
- Miliaria rubra
- Milia
DIAGNOSTIC TESTS & INTERPRETATION
Diagnostic Procedures/Other
Clinical diagnosis confirmed by biopsy
Test Interpretation
- Apocrine duct rupture results in perifollicular foamy macrophages creating elevated lesions in the reticular dermis. Dilation and hyperkeratosis of the follicular infundibula can be seen and may play an important diagnostic role. Chronic perifollicular and dermal perivascular inflammatory infiltrate, epidermal acanthosis, epidermal edema, and spongiosis accumulate below the plug and in the upper infundibulum, resulting in fibrosis and chronic lymphocytic/histiocytic inflammation of the dermis (5).
- Perifollicular xanthomatosis (foam cells) is a specific finding.
TREATMENT
GENERAL MEASURES
- Nonsurgical treatment is difficult because no single treatment has been shown to be very effective, but involves the avoidance of excessive sweating or heat. Consider dermatology consultation.
- No large trials have been carried out into treatments for Fox-Fordyce disease. Most treatment recommendations have come from single reports in the research literature, and therefore the advice is limited by lack of evidence.
MEDICATION
First Line
- Topical clindamycin with propylene glycol
- Intralesional corticosteroids (triamcinolone)
- Topical corticosteroids (class 3 to 4)
Second Line
- Topical retinoids (tretinoin, adapalene)
- Topical pimecrolimus ointment (6)
- Systemic isotretinoin
ADDITIONAL THERAPIES
Antihistamines for pruritus
SURGERY/OTHER PROCEDURES
Electrocoagulation, surgical excision, and liposuction-assisted curettage (4) have all demonstrated efficacy in the treatment of Fox-Fordyce disease.
COMPLEMENTARY & ALTERNATIVE MEDICINE
- Oral contraceptives; testosterone
- Ultraviolet lights; x-ray
- Pramoxine with menthol/camphor can also be a useful adjuvant for pruritus.
ONGOING CARE
PATIENT EDUCATION
Avoid activities that may result in increased sweating as this can exacerbate the disease.
PROGNOSIS
Lesions may last months to years or may subsequently resolve with treatment. Long-term follow-up studies are not available.
REFERENCES
11 Fox GH, Fordyce JA. Two cases of a rare popular disease affecting the axillary region. J Cutan Genitourinary Dis. 1902;20:1-5.22 Kamada A, Saga K, Jimbow K. Apoeccrine sweat duct obstruction as a cause of Fox-Fordyce disease. J Am Acad Dermatol. 2003;48(3):453-455.33 Yost J, Robinson M, Meehan SA. Fox-Fordyce disease. Dermatol Online J. 2012;18(12):28.44 Chae KM, Marschall MA, Marschall SF. Axillary Fox-Fordyce disease treated with liposuction-assisted curettage. Arch Dermatol. 2002;138(4):452-454.55 B ¶er A. Patterns histopathologic of Fox-Fordyce disease. Am J Dermatopathol. 2004;26(6):482-492.66 Pock L, Svrckov ¡ M, Mach ¡ckov ¡ R, et al. Pimecrolimus is effective in Fox-Fordyce disease. Int J Dermatol. 2006;45(9):1134-1335.
ADDITIONAL READING
- Bormate ABJr, Leboit PE, McCalmont TH. Perifollicular xanthomatosis as the hallmark of axillary Fox-Fordyce disease: an evaluation of histopathologic features of 7 cases. Arch Dermatol. 2008;144(8):1020-1024.
- Helm TN, Chen PW. Fox-Fordyce disease. Cutis. 2002;69(5):335, 342.
- Ozcan A, Senol M, Aydin NE, et al. Fox-Fordyce disease. J Eur Acad Dermatol Venereol. 2003;17(2):244-245.
CODES
ICD10
L75.2 Apocrine miliaria
ICD9
705.82 Fox-Fordyce disease
SNOMED
- Fox-Fordyce disease
- Fox-Fordyce disease of axillae
- Fox-Fordyce disease of vulva (disorder)
CLINICAL PEARLS
- Fox-Fordyce presents as chronic pruritic papules in areas where sweat glands are concentrated.
- Pruritus may be extreme and out of proportion to the erythema.