20 - Disorders of Sweat Glands Flashcards
Sweat glands
- Body has 2-5 million sweat glands
- Apocrine and eccrine
Apocrine sweat glands
- Inactive until puberty, produce thick fluid
- Secretions come in contact with bacteria on the skin and produce characteristic “body odor”
- Found in axillary and genital areas
Eccrine sweat glands
- Approximately 3 million eccrine sweat glands, secrete a clear, odorless fluid
- Aid in regulating body temperature
- Not found on mucous membranes or nail beds
- Areas of concentration:facial, palms, plantar feet, and axillae
Eccrine gland anatomy
- Coiled secretory portion
- Straight dermal duct
- Coiled dermal duct
- Coiled intraepidermal duct
Eccrine gland duct system
Dermal duct
o Function is to modify secretion with resorption of water
Coiled duct
o Found deep in reticular dermis or subcutaneous-dermal junction
o Opens into duct system through dermal layer
o Enters epidermis between the papillae
o Corkscrew channel extends to outer layer of epidermis and terminates as a trumpet-shaped pore
Stimulation of eccrine glands
- Glands on forehead, palms and soles respond to psychogenic stimulation
- Glands on hairy surfaces respond to thermal stimulation
- Thermal sweating – dependent on intact hypothalamus
- Psychogenic sweating – limbic system control
Role of hypothalamus in sweating
- Can be triggered by exercise, temperature change, hormones, stress
Neurotransmitters in sweating
- Once triggered, the hypothalamus sends messages down the spinal cord via neurotransmitters
- The neurotransmitters travel down the spine via ganglion or sympathetic nerves
- These ganglions travel to nerves, which reach the skin’s surface
Role of neurotransmitters
- Neurotransmitters act as “vehicles,” transmitting information from the hypothalamus to the skin’s surface
- The neurotransmitters can “exit” at various places along the spinal cord. The “exit” determines the location of skin innervation.
- T2-T4 = innervation of skin of face, T2-T8 = innervation of skin of upper limbs, T4-T12 = innervation of skin of trunk, T10-T12 = innervation of skin of lower limb
- Acetylcholine (Innervates eccrine sweat glands)
- Catecholamines (Innervate apocrine sweat glands)
Sweat production
- Once innervated, the apocrine and eccrine glands will produce SWEAT
- Contains sodium, chloride, potassium, lactate, urea
- Clear hypotonic solution, pH ranges from 4-6.8
What serves as the body’s thermoregulatory center?
o The hypothalamus
o The adrenal cortex
o The frontal lobe
Hypothalamus
What neurotransmitter innervates eccrine sweat glands?
o Acetylcholine
o Catecholamine
o Glucose
Acetylcholine
The hypothalamus can be triggered by all these except: o Stress o Exercise o Obesity o Temperature change
Obesity
Sweating disorders
- Anhydrosis
- Hyperhydrosis
Anhydrosis
o Inability of the body to produce and or deliver sweat to the skin surface
o General: hypothalamus problems (tumor, heat stroke, mechanical trauma, congenital defects)
o Localized: polio, multiple sclerosis, alcoholic neuritis, diabetic neuritis, atrophy of the gland, radiation dermatitis
Hyperhydrosis
o Increased eccrine sweating (Emotional hyperhidrosis, Thermoregulatory hyperhidrosis)
o Diagnosed in 2.8% of the U.S. population
o 70% of those with symptoms do not consult a physician
o Peaks in early adulthood
Changes seen in hyperhydrosis
- Hyperhidrosis is a state of excessive sweating of the axilla, palms, soles, or face that interferes with daily activities
Involves the eccrine sweat glands, however: o Sweat glands are NORMAL o No change in size o No change in shape o No change in number
Hyperhidrosis patient presentation
- Main complaint is social embarrassment from wetness of hands and odor of feet
- May have pruritis, burning and blistering from increased moisture
- Increased incidence of dermatophyte, bacterial and viral infections
- Leads to tinea pedis, pitted keratolysis and verrucae
- May sweat so much that it beads up on toes and hands or drips
- Either present with erythematous, shiny feet from the moisture or pale, boggy thick soles from absorption of excessive moisture (bromhidrosis)
- Often requires treatment
Bromhidrosis
- Foot odor or sogginess – end stage hyperhydrosis
- Apocrine or eccrine
- Foul smell
- Bacterial decomposition of epidermal lipids and fatty acids
- Propionibacterium is responsible for the cheesy odor
- Tenderness (Blistering & fissuring of intertriginous and weight-bearing areas)
- Moisture induced growth of many micro-organisms
Different forms of hyperhidrosis
- General = secondary to a variety of conditions
- Focal = primary (idiopathic), associated with neuropathies, secondary to spinal disease/injury
Cause of primary or idiopathic hyperhidrosis
- Exact cause is unknown
- Familial or genetic?
- Excessive Sympathetic Activity (constant stimulation)
Those diagnosed with hyperhidrosis have abnormal eccrine sweat glands.
o TRUE
o FALSE
False
- Hyperhidrosis involves which sweat gland type?
o Apocrine
o Eccrine
Eccrine
Hyperhidrosis/bromhidrosis treatment goals
o Reduction of moisture
o Reduction of bacterial population
First line therapy for mild cases
o Foot gear: Should be non-occlusive, leather or canvas, avoid synthetic materials like plastic (Open sandals)
o Socks: Should be absorbent wool/synthetic blend. Avoid nylon and all cotton. Change midday
o Talc
o Tolnaftate: zeasorb powder-45% microporous cellulose, twice the absorbancy of talc
Therapy for odor
Activated charcoal inserts
Therapy for antipersperant and astringent effects
o Aluminum chloride hexahydrate (i.e. Drysol)
o Burows solution (1:10 to 1:40 conc.)
o Aluminum sulfate
o Calcium acetate
What is the NUMBER ONE CHOICE for antipersperant effects?
DRYSOL***
- astringent, antibacterial, and antifungal properties
- effective for tinea pedis
- NUMBER ONE CHOICE
- skin should be completely dry, applied at bedtime
- more effective if occluded
- initial tx: 3-5 nights until controlled then once every 4-5 days.
What are the treatment options for moderately severe cases - bromhidrosis?
Aldehydes, which produce a blockage within the stratum corneum
“I’ve never used any of these”
Examples of aldehydes used for the treatment of bromhidrosis (moderate cases)
- Formalin (5-10%)
- Potent wide-spectrum antiseptic and germicide
• Very irritating to skin - Glutaraldehyde
- Germicidal, sporicidal and anhydrotic with constant use
- Can cause brown discoloration
- 10% solution, soak feet 3 times/wk for 1-2 week - Methenamine gel
- For moderate hyperhidrosis of soles
- No contact sensitization
How does treatment work?
- The metal ions in the topical antiperspirant damage the lining of the sweat gland.
As damage continues, a PLUG is formed over the sweat gland. - Sweat production never ceases, the gland is simply plugged
- Sweating will return as the skin undergoes regeneration or shedding
- Therefore…topical treatment is NOT a cure!
Topical Treatments work by ________ sweat glands.
o Destroying
o Plugging
o Melting
Answer: plugging
Iontophoresis
- Used for palmar and plantar hyperhidrosis
- Passage of direct electrical current onto skin’s surface
- Device can be purchased for home use
- Sit with hands or feet in shallow tray of water
- Allow 15 – 20 milli-amps of electrical current to pass through water
- Use for 10 days, 30 minutes each day
- Maintenance therapy needed
Contraindications for ionophoresis
- Who are pregnant
- Have pacemakers
- Have metal implants
- Have cardiac conditions
- Have epilepsy
Systemic treatment
- Anticholinergics can be used in treating hyperhidrosis
- Ex: glycopyrrolate, oxybutynin, benztropine, propantheline
- Most effective for cranio-facial hyerhidrosis
- May consider other anti-anxiety medications as well
Treatment with anticholinergics
- Long term therapy is required
- Limited use in treating hyperhidrosis
- Only 21% effective
Major side effects:
o Dry mouth, dry eyes
o Constipation, difficulty with urination
o Blurred vision
Anticholinergics block transmission of
o Catecholamines
o Epinephrine
o Acetylcholine
Acetylcholine
Botox injections
- Botox injections can be used to treat axillary, palmar, and plantar hyperhidrosis
- Analgesic applied prior to injection
- Nerve block applied to ulnar or radial nerve prior to palmar injection
- Starch Iodine test done prior to injection
- Delineates areas of excess sweating with black-purple discoloration of the skin
- Botox blocks the release of acetylcholine at the site of the neuromuscular junction.
- Sweat glands are not stimulated, and sweat production ceases
- Pros - Lasts 6-7 months, 90% effective
- Cons: Very painful to the palms and soles of feet, expensive: $1400-$1600 per treatment
Local excision
- Used only for axillary hyperhidrosis
- Starch Iodine test done prior to excision
- Performed under local anesthesia
- Vasoconstrictor applied to axillary region
- Small incisions made
Endoscopic thoracic sympathectomy
- Last treatment option- PERMANENT
- Uncommon for plantar hyperhidrosis
- Surgery performed under general anesthesia
- Goal of surgery is to excise or ablate the ganglion that innervate the sweat glands
- Performed most frequently for palmar hyperhidrosis
- Performed through thorascope or video
- Minimally invasive
What is pitted keratolysis?
o Associated with hyperhidrosis, not an actual sweat gland disorder
o Superficial infection
o Caused by several different bacteria
o Small, circular “punched out pits” in stratum corneum
o Can conjoin to form bizarre patterns on foot
o Common in children and adolescents, Boys>Girls
Etiology of pitted keratolysis
o Primary isolate corynebacterium with no odor
o Primary isolate micrococcus sedentarius with odor
o Others: Streptomyces, Dermatophilus congolensis
o Not easy to culture bacteria, need to grind up stratum corneum to find it
Treatment for pitted keratolysis
MAINSTAY TREATMENT
- Topical 2% erythromycin solution or gel x 2 wks – MOST COMMON
- Topical 1% clindamycin solution or gel x 2 wks
Details on treatment options for pitted keratolysis
o Similar to that of hyperhidrosis, but also have to treat bacterial infection.
o Eliminate shoes and socks that don’t “breathe well”
o Astringent foot soaks to control the hyperhidrosis
o Benzoyl peroxide (antibacterial and anti-keratolytic)
o In severe cases, oral Erythromycin 1g daily x 2 wks
But remember…
- Mainstay is a topical antibiotic solution/gel for 2 weeks (erythromycin* or clindamycin)
What is porokeratosis plantaris discreta?
AKA Intractable plantar keratoma or IPK
o Hyperkeratosis (of epidermal sweat duct)
o 1-3mm diameter punctate lesion, white or yellow
o Caused by pressure on weight bearing aspect of plantar skin
o Tender with side to side pressure and direct
o Non-vascular on debridement
o Debate as to whether the sweat gland is involved with cause
o Sweat duct is dilated below plug, not likely the cause
o May get up to 1.5cm in depth, histologically similar to tyloma and heloma
Treatment of porokeratosis plantaris discreta (or IPK)
o Topical keratolytics
o Debridement
o Padding
o Intralesional injection of alcohol sclerosing solution
o Enucleation of plug and dessication of base
o Surgical excision
Eccrine poromas
Note: can also be apocrine in origin
- Benign Lesion- derived from cells of the terminal duct and connected to the epidermis
- Slow growing, painless nodule
- May present as superficial and smooth-surfaced or flat lesion
- Resembles a pyogenic granuloma, dermatofibroma, or amelanotic melanoma
- Rubbery and firm
- Can get as long as 3 cm in diameter
- May get infected or ulcerate
- Found on surface
- interdigital, toes, palm, soles
- Affects mostly women in 4th decade
- Tx: surgical excision and electrodessication
- Must rule out malignancy
Describe dyshidrosis
- Not actually due to “bad/excess” sweating – the name is a misnomer
- Dyshidrotic Eczema or Pompholyx
- Small, fluid filled vesicles (looks a lot like pustual tinea or athlete’s foot)
- Palms and soles – painful
- Last for 3-4 weeks, intense pruritus, blisters, then dry and crack to fissures
Etiology of dyshidrotic eczema
o Unknown o Associated with atopic dermatitis o Associated with asthma and hay fever o Eruptions are seasonal in above patients o Associated with neurotic history
Differential diagnosis for dyshidrosis
o Fungal Etiology
o Must rule out fungal cause – KOH, biopsy
Risk factors for dyshidrosis
o 2:1 female to male ratio
o Stress
o Exposure to metal salts (chromium, cobalt, nickel) through cement or mechanical work
o Seasonal allergies
o Occupation with frequent exposure of skin to a wet environment
Treatment for dyshidrosis
- Topical creams: corticosteroid cream or ointment
- Wet compresses
- Antihistamines
- Oral steroid
- UV light therapy
- Botulinum toxin, for severe cases only
NOTE:
o Recurrence is common
o Avoid triggers
Keratodermas
- Not truly a sweat gland disorder
- May be related to anhydrotic state
- Localized or regional
- Similar in appearance to diffuse or isolated hyperkeratosis
- May have systemic manifestations
- Most are inherited, autosomal dominant**
Diffuse keratoderma
- Diffuse hyperkeratosis
- Palmar and plantar skin
- So thick the skin cracks and fissures
Palmoplantar keratoderma treatment
It is persistent and difficult to treat o Debridement with topical keratolytics o Sharp debridement by scalpel o Topical vitamin A and emollients o Cushioned or shock absorbing insoles to reduce pressure
FOCUS
- Sweating – hyperhidrosis, pitted keratolysis (KNOW TREATMENT**) – pediatrics treatment
- Some of these have some sort of an obscure association with sweating but not necessarily a direct effect
