Apocrine glands are adnexal glands that are distributed in the scalp, the axillae, the anogenital region, the eyelids (Moll's glands), the external auditory meatus (ceruminous glands), and the mammary glands. Apocrine glands can also be found in a more limited distribution on the face and abdomen. Apocrine glands are quiescent until puberty. Embryologically, apocrine glands develop from the upper bulge of the hair follicle late in the fourth month of gestation, with continued development as long as hair follicles develop. A primary epithelial germ (hair germ) grows down from the epidermis and forms an apocrine gland, sebaceous gland, and hair follicle. Apocrine glands are composed of three components: (1) the intraepithelial duct, (2) the intradermal duct, and (3) a coiled gland in the deep dermis or at the junction of the dermis and subcutaneous fat, which contains the secretory portion. The coiled gland consists of one layer of secretory cells around a lumen that is about ten times the diameter of its eccrine counterpart. Contractile myoepithelial cells, a hyaline basement membrane, and connective tissue surround the coiled gland. The predominant mode of apocrine secretion is decapitation, a process where the apical portion of the secretory cell cytoplasm pinches off and enters the lumen of the gland. Apocrine sweat consists mainly of sialomucin. Apocrine sweat is more viscous and produced in much smaller amounts than eccrine sweat (which actually is the wet portion of axillary sweat). The exact function of apocrine glands is unclear, although they are thought to represent scent glands. Their primary sympathetic stimulation is adrenergic.1
Four disorders are considered in this chapter: two primary disorders of the apocrine glands, namely (1) apocrine bromhidrosis and (2) apocrine chromhidrosis; and two secondary disorders, (1) Fox–Fordyce disease and (2) hidradenitis suppurativa (acne inversa), in which apocrine glands become secondarily affected.
Apocrine Bromhidrosis at a Glance
- Apocrine bromhidrosis refers to an offensive or unpleasant body odor arising from apocrine gland secretions.
- Chronic disorder, most often developing in the axillae, but may also involve the genitals or plantar aspect of the feet.
- The best-characterized short chain fatty acid causing odor is ϵ-3-methyl-2-hexenoic acid.
- Should be distinguished from eccrine bromhidrosis.
- Surgical removal of affected glands may be effective.
Body odor, osmidrosis, is a common phenomenon in a postpubertal population. Bromhidrosis refers to body odor, which is excessive or particularly unpleasant and apocrine bromhidrosis to such an offensive odor that arises from apocrine glands. It is most often mentioned in the axillae. This condition may contribute to impairment in an individual's psychosocial functioning. The terminology in the literature is sometimes confusing, using osmidrosis to imply offensive odor, and bromhidrosis to imply osmidrosis in the setting of concomitant hyperhidrosis.2
Disease onset after puberty is common and tends to be more prevalent in African-American populations. There is no geographic predilection, although summer months or warm climates may aggravate the disease. Poor ...