Title: Dermatoses Resulting from Physical Factors
1Dermatoses Resulting from Physical Factors
- Chapter 3
- Andrews Diseases of the Skin
- JoAnne M. LaRow, D.O.
2Heat Injuries
- Thermal Burns
- Electrical Burns
- Hot Tar Burns
- Miliaria
- Miliaria Crystalline (Sudamina)
- Miliaria Rubra (Prickly Heat, Heat Rash)
- Miliaria Pustulosa
- Miliaria Profunda
- Postmiliarial Hypohidrosis
- Tropical Anhidrotic Asthenia
- Occlusion Miliaria
3Thermal Burns
- First-degree burn- active congestion of
superficial blood vessels - This causes erythema sometimes followed by
epidermal desquamation - Sunburn
- Constitutional reactions occur if area is large
- Pain and increased surface heat may be severe
4Second-degree burns
- Deep is pale and anesthetic
- Injury to reticular dermis compromises blood flow
and destroys appendages - Healing takes gt 1 month
- Scarring occurs
- Two types-superficial and deep
- Superficial-transudation of serum from
capillaries, causing edema of superficial tissues - Vesicles and blebs form from serum gathering
beneath the outer layers of the dermis - Complete recovery without scar or blemish is usual
5Second-Degree Burns
- Inflicted scalds severe second degree burns
after dipping - B two days after incident-to lower extremities
and perineum - C foot and lower leg
6Second-Degree Burn
- Accidental scald
- Splash-and-droplet pattern of an accidental scald
from hot cup of tea
7Second-Degree Burn
8Third-degree burns
- Full-thickness tissue loss
- Often loss of subcutaneous tissue occurs
- Since skin appendages are destroyed there is no
epithelium for regeneration - An ulcerating wound occurs
- Healing leaves a scar
- Followed by constitutional symptoms
9Fourth-degree burns
- Destruction of entire skin and subcutaneous fat
with any underlying tendons - Requires grafting for closure
- Constitutional symptoms occurs
- Constitutional symptoms depend on size of area
involved, depth, and especially location - The more vascular the involved area, the more
severe the symptoms
10Thermal Burns
- Prognosis is poor when large surfaces are
involved - Particularly when gt two thirds of body surface is
burned - Infection of the wound
- Cellulitis, sepsis, with seeding of internal
organs (ie meninges, lungs, kidneys) - Irregularities in electrolytes and fluid balance,
loss or serum proteins -
- Symptoms of shock may appear within 24-hrs
- Next, symptoms of toxemia from the absorption of
destroyed tissue on wound surface - Symptoms of wound infection may then occur as a
result of contamination with pyogenic organisms - Symptoms of all three may merge making
differentiation difficult
11Complications of thermal burns
- Excessive scarring with keloidlike scars or flat
scars with contractures of joints - Chronic ulcerations because of local impaired
circulation - Burn scars may be the site of carcinoma or sarcoma
12Treatment
- For minor thermal burns-prompt cold applications
until pain has resolved - Do not open vesicles or blebs, they provide a
natural barrier - If tense and painful evacuate fluid under strict
aseptic conditions via puncture of the wallto
allow blister to collapse - Apply topical antibiotic
- Severe deep wounds silver sulfadiazine ointment
is indicated - Antibiotics, fluid, and electrolyte support,
supplemental vitamins
- Collagen-synthetic bilaminate membranes may
be used - In many centers, cultured epidermal grafts, both
autologous and allogeneic, are being utilized - Morbidtiy and mortality following severe burns is
often due to bacterial and fungal infection - Definitive tx consists of antishock measures,
debridement of loose skin and dirt, and
application of silver sulfadiazine ointment
13Treatment
- Expedient primary excision of deep dermal and
full-thickness burn wounds with subsequent
grafting is standard of care - Severe second- and third degree burns require
specialized teams of physicians working together
to provide most effective tx
14Electrical Burns
- Two varieties
- Contact and flash
- Contact- small but deep, causing some necrosis of
underlying tissues - Flash-burns usually cover a large area and are
similar to a surface burn and should be tx as
such - Lightening may cause burns after direct strike,
where an exist and an entrance wound are visible - Lightening is the most lethal type of strike,
cardiac arrest or other internal injuries may
occur
15Electrical Burns
- Other types of strikes are indirect and result in
linear burns that are either linear in areas at
which sweat was present are feathery or
aborescent pattern, which is believed to be
pathognomonic
16Electrical Burn
- It is characterized by erythema, edema, bulla
formation and sloughing of the necrotic epidermis
17Electrical Burn-pathology
- Blistering and elongated keratinocytes
18Hot Tar Burns
- Demling has reported that the polyoxyethylene
sorbitan in Neosporin ointment is an excellent
dispersing agent that facilitates the removal of
hot tar from burns
19Miliaria
- Retention of sweat as a result of occlusion of
eccrine sweat ducts and pores - Produces an eruption that is common in hot, humid
climates such as the tropics and during the hot
summer months in temperate climates - Occlusion of eccrine sweat gland obstructs
delivery of sweat to the skin surface - Eventually backed-up pressure causes rupture of
sweat gland or duct at different levels - Escape of sweat into adjacent tissue produces
miliaria - Different forms of miliaria occur depending on
the level of injury to the sweat gland
20Miliaria Crystalline
- Characterized by small, clear, superficial
vesicles without inflammation - Appears in bedridden pts in whom fever produces
increased perspiration or when clothing prevents
dissipation of heat and moisture, as in bundled
children - Lesions are asymptomatic and rupture at the
slightest trauma - Self-limited no tx is required
21Miliaria Crystallina
- Minute, descrete vesicles resulting from profuse
sweating secondary to a high fever
22Miliaria Crystallina
23Miliaria Rubra
- Lesions are descrete, extremely pruritic,
erythematous papulovesicles with sensation of
prickling, burning, or tingling - Tingling may become confluent on a bed of
erythema - Most frequently affected sites antecubital and
popliteal fossae, trunk, inframammary areas,
abdomen - Site of injury is prickle cell layer where
spongiosis is produced
24Miliaria Rubra
25Miliaria Pustulosa
- Always preceded by some other dermatitis that has
produced injury, destruction, or blocking of
sweat duct - Pustules are distinct, superficial, and
independent of hair follicle - Pruritic pustules occur most frequently on
intertriginous areas, flexure surfaces of
extrmities, sctrotum, and back of bedridden pts - Usually pustules contain sterile material, but
may contain nonpathogenic cocci
26Miliaria Profunda
- Nonpruritic, flesh-colored, deep-seated, whitish
papules - Asymptomatic, usually lasting only 1 hr after
overheating has ended - Concentrated on the trunk and extremities
- Except for face, axillae, hands, and feet(where
there may be a compensatory hyperhydrosis), all
sweat glands are nonfunctional - Occlusion is in upper dermis
- Only seen in tropics usually following a severe
bout of miliaria rubra
27Postmiliarial Hypohidrosis
- Results from occlusion of sweat ducts and pores
and may be severe enough to impair ones ability
to perform sustained work in a hot environment - Affected pts may show decreasing efficiency,
irritability, anorexia, drowsiness, vertigo, and
headache they may wander in a daze - Hypohidrosis invariably follows miliaria
- The duration and severity of hypohidrosis are
related to severity and duration of miliaria - Sweating may be depressed to half the normal
amount for as long as 3 weeks
28Tropical Anhidrotic Asthenia
- Rare form of miliaria with long-lasting pore
occlusion, producing anhidrosis and heat retention
29Occlusion Miliaria
- May be produced with accompanying anhidrosis and
increased heat stress susceptibility after
application of extensive polyethylene film
occlusion for gt 48 hrs - Tx-place pt in a cool environment
- Even a night in an air-conditioned room helps
alleviate the discomfort - Anhydrous lanolin resolves occlusion of pores and
may help restore normal sweat secretions - Hydrophilic ointment helps dissolve keratinous
plugs facilitating sweat flow - Soothing, cooling baths containing Aveeno
colloidal oatmeal or cornstarch in moderation
30Occlusion Miliaria
- Mild cases may respond to dusting powders, such
as cornstarch or baby talcum powder - A lotion containing 1 menthol and glycerin and
4 salicylic acid in 955 alcohol is effective - This should be dabbed on affected areas several
times daily until desquamation sets in - An oily shake lotion such as calamine lotion,
with 1 or 2 phenol may be effective
31Erythema (pigmentatio) Ab Igne
- Aka toasted skin syndrome
- Persistent erythema or coarsely reticulated
residual pigmentation resulting from it - Produced by long-continued exposure to excessive
heat without production of a burn - It begins as a mottling caused by local
hemostasis and becomes a reticulated erythema,
leaving pigmentation
32Erythema Ab Igne
- Most common on the legs of women as a result of
warming in open fireplaces, radiators, or heaters - Similar changes may be produced with a hot water
bag or electric heating pad - Also occurs in cooks, stokers, invalids, and
others exposed to long periods of moderate heat - Epithelial atypia and Bowens disease has been
reported
- All the various phases usually are present
simultaneously in a patch, the color varying from
pale pink to old rose or dark purplish brown - After cause is removed the color tends to
disappear gradually, but sometimes pigment is
permanent
33Erythema Ab Igne
- Reticulated hyperpigmentation with some epidermal
atrophy and scaling secondary to use of a heating
pad
34Heat sources causing EAI
- Steam radiators
- Car heaters
- Heated reclining chairs
- Heating blankets
- Hot bricks
- Infrared lamps
- Heating pads
- Hot water bottles
- Electric stove/heater
- Open fires
- Coal stoves
- Peat fires
- Wood stoves
35Key Features
- Localized areas of reticulated erythema and
hyperpigmentation - Due to chronic exposure to a nonburning heat
source - Common locations lumbosacral region and shins
- Key pathologic finding is squamous atypia
- There is a risk of cutaneous malignancy, in
particular squamous cell carcinoma - Also Merkel cell carcinoma risk
- Latent period of 30 years or more with carcinoma
36Treatment
- Use of bland emollients is helpful
- No effective treatment
- Kligmans combination of 5 hydroquinone in
hydrophilic ointmant containing 0.1 retinoic
acid and 0.1 dexamethasone may reduce unsightly
pigmentation
- Histologically, an increased amount of elastic
tissue in the dermis is seen - Changes are similar to actinic elastosis, and has
been suggested to call these changes thermal
elastosis
37Cold Injuries
- Local cold injuries are divided into chilblain,
frostbite, and immersion injury - Immersion foot is encountered almost entirely in
the armed forces - Intense vasoconstriction resulting from local
action of cold and reflex vasoconstrictor
stimulation is reinforced by the passage of cold
blood through the vasomotor center - Vasoconstriction evokes tissue anoxia
- Decreased muscular activity further diminishes
blood supply - Ice crystal formation in blood vessels usually
does not occur, but when it does necrosis occurs
38Chilblains
- Occurs chiefly on hands, feet,ears, and face,
especially in children - Onset is enhanced by dampness
- Pts are usually unaware of injury until they
develop burning, tiching, and redness - Areas are bluish red, the color partial or
totally blanches with pressure, and are cool to
touch - Chronic chilblains occurs repeatedly during cold
weather and disappears during warm weather
- Recurrent, localized erythema and swelling caused
by exposure to cold - Blistering and ulcerations may develop in severe
cases - In pts predisposed by poor circulation even
moderate exposure to cold may produce chilblains - Acute chilblains is the mildest form of cold
injury
39Chilblains (pernio)
40Treatment
- Affected areas should be cleansed with water and
massaged gently with warm oil each day and should
be protected against further injury and exposure
to cold or dampness - If feet are affected, woolen socks should be worn
at night during cold months - Careful use of electric pads may be used
- Smoking strongly discouraged
- Nifedipine 20mg TID
- Vasodilators (nicotinaamide 100 mg TID or
dipyridamole 25 mg TID) - Systemic corticoid tx is helpful in chilblain
lupus erythematosus - Pentoxifylline may be useful
41Frostbite (Congelation)
- When soft tissue is frozen and locally deprived
of blood supply - Ears, nose, cheeks,fingers,and toes most common
sites - Frozen part is painless and becomes pale and
waxy - Various degrees of tissue destruction similar to
those of burns are seen
- Erythema and edema, vesicles and bullae,
superficial gangrene, deep gangrene - Injury to muscles, tendons, periosteum, and
nerves - Arolla index-formula linking duration of exposure
(defined by temperature and wind chill index)
with frostbite
42Frostbite
43First-Degree Frostbite
44Treatment
- When the skin flushes and is pliable, thawing is
complete - Supportive measures bed rest, high protein/high
calorie diet, wound care, avoidance of trauma,
avoid rubbing of affected parts - After swelling and hyperemia have developed, bed
rest with limb slightly flexed, elevated and at
rest - Room temperature relieves pain and helps prevent
tissue damage
- Early- (before swelling develops) covering body
with clothing or a warm hand or other body
surface to maintain a warm temperature to
maintain adequate blood circulation - Rapid rewarming in bath water between 100 degrees
and 110 F - Analgesics(because rewarming is painful)
- Slow thawing results in more extensive tissue
damage
45Treatment
- Protection by a heat cradle may be helpful
- Anticoagulants to prevent thrombosis and gangrene
- Papaverine and nicotinic acid may reduce
vasospasm - Antibiotics for prophylactic measures and an
updated tetanus immunization is recommended - Recovery may take months
46Immersion Foot Syndromes
- Trench Foot
- Warm Water Immersion Foot
47Trench Foot
- Results from prolonged exposure to cold, wet
conditions without immersion or actual freezing - Term derived from trench warfare in World War 1,
when soldiers stood, sometimes for hours, in
trenches with a few inches of cold water in them - Lack of circulation produces edema, paresthesias,
and damage to blood vessels - Gangrene may occur in severe cases
- Tx-removal from causal environment, bed rest, and
circulatory restoration - Measures underlined on tx for frostbite should be
performed
48Warm Water Immersion Foot
- Exposure of feet to warm, wet conditions for 48
hrs or more may produce a syndrome of maceration,
blanching, and skin wrinkling of soles and sides
of feet - Itching and burning with swelling may persist a
few days after removal of the cause, but
disability is temporary - Commonly seen in military service members in
Vietnam
- Also seen in persons wearing insulated boots, the
so-called moon-boot syndrome - Tx-by allowing feet to dry for a few hrs out of
24 hrs - Or by greasing soles with a silicone grease
once/day - Recovery is usually rapid and complete if dried
thoroughly for a few hrs
49Tropical immersion Foot
- Seen after continuous immersion of the feet in
water or mud of temperatures above 71.6 degrees F
(22 degrees C) for 2-10 days - AKA paddy foot in Vietnam
- Erythema, edema, and pain of the dorsal feet
- Also fever and adenopathy
- Resolution occurs 3 to 7 days after the feet have
been dried
50Warm Water Immersion Foot
- This was known as paddy foot in Vietnam
- It involves erythema, edema, and pain of the
dorsal feet, and fever and adenopathy - Resolution occurs 3-7 days after the feet have
been dried - Can be prevented by allowing the feet to dry for
a few hrs out of every 24 or by greasing the
soles with a silicone grease once daily - Recovery is usually rapid if feet are thoroughly
dried for a few hrs
51Dermatoses with Cold Hypersensitivity
- Erythrocyanosis Crurum
- Acrocyanosis
- Cold Panniculitis
- Exposure to cold produces abnormal reactions in
several disease states - These reactions are mediated through globulins ie
cryoglobulin and cryofibrinogen - Also histamine, serotonin, leukotrienes,
protaglandins, kinins, and cold hemolysins may be
involved
52Erythrocyanosis Crurum
- Small tender nodules may be found on palpation
- Nodules may break down and form small, multiple
ulcers - Affected limbs are cold to touch
- Seen in northern countries and probably due to an
abnormal reaction of blood vessels to prolonged
cold
- Characterized by slight swelling and a bluish
pink tint of the skin of the legs and thighs of
young girls and women - May be unilateral
- Atypical varieties are common, some presenting
cinnabar red spots, bullae, indurations, and
lichenoid papules - May be a history of cramps in the legs at night
53Acrocyanosis
- A persistent cyanosis with coldness and
hyperhidrosis of fingers and hands - May also be present on toes and feet
- Chiefly occurs in young women, but not rare in
young men - At times, on cold exposure, a digit becomes stark
white and insensitive (acroasphyxia) - Cyanosis increases as the temperature decreases
and changes to erythema with elevation of
dependent part - Cause is unknown
- Smoking, coffee, and tea should be avoided
54Acrocyanosis
- Remitting necrotizing acrocyanosis is a term
applied to functional vascular spasm or organic
occlusion that produces pain in hands and feet,
with ateas of coldness, cyanosis, andnecrosis of
the tops of fingers and toes - This has been reported to occur without prodromal
or constitutional symptoms
55Cold Panniculitis
- After exposure to severe cold, well-demarcated
erythematous warm plaques may develop,
particularly on the cheeks of young children - Lesions usually develop within a few days after
exposure, and resolve spontaneously in 2
weeks(approx)
56- Lesions are readily reproducible by placing an
ice cube on the volar aspect of the forearm for 2
minutes - This type of panniculitis is seen mostly in young
children whose fat contains more high saturated
fatty acids, which have a higher melting point
and a lower solidification point than an adults
less saturated fat - Pts outgrow this susceptibility
- No tx is indicated
- Popsicle dermatitis is a temporary redness and
induration of the cheek in children resulting
from sucking Popsicles
57Sunburn and Solar Erythema
- Parts of solar spectrum important to
photomedicine - Ultraviolet radiation , 400nm
- Visible light 400 to 760 nm
- Infrared radiation beyond 760 nm
- Visible light has little biologic activity,
except for stimulating the retina - Infrared radiation is experienced as radiant heat
- Below 400 nm is the ultraviolet spectrum, divided
into three bands - UVA, 320 to 400 nm
- UVB, 290 to 320 nm
- UVC, 200 to 290 nm
- UVA is divided into two subcategories UVA I(340
to 400 nm) and UVA II(320 to 340 nm) - Virtually no UVC reaches the earths surface,
because it is absorbed by the ozone layer
58- UVA is reflected from sand, snow, or ice to a
greater degree than UVB - Amount of ultraviolet exposure increases at
higher altitudes, is greater in tropical regions,
and temperate climates in summer - A large portion of UVA and UVB may be reflected
from sand, snow, ice, and water - Cloud cover is a poor UV absorber
- Mercury-vapor lamp or sunlamp bulb produces
mostly UVB( stronger inducer of erythema)
- Minimal erythema dose (MED) is the minimal amount
of a particular wavelengh of light capable of
inducing erythema on an individuals skin - UVB is 1000 times more erythemogenic than UVA
- UVA is 100 times greater than UVB radiation
during the midday hours - Most solar erythema is cause by UVB
- Sunlight early and late in the day contains more
UVA
59Clinical signs and symptoms
- Sunburn is normal cutaneous reaction to sunlight
in excess of an erythema dose ( the amount that
will induce redding) - UVB erythema peaks at 12 to 24 hrs after
exposure, but onset is sooner and severity
greater with increased exposure - Erythema is followed by tenderness, blistering,
which may become confluent
- Edema commonly occurs in extremities and face
chills, fever, nausea, tachycardia, and
hypotension may be present - Sever cases symptoms may last as long as a week
- Dequamation is common about a week after sunburn
even in non-blistering areas
60- Delayed tanning is induced by UVB and UVC
wavelengths and begin 2 to 3 days after exposure
and last 10-14 days - Delayed tanning does produce some protection from
further solar injury , it is at the expense of
damage to the dermis and epidermis - Tanning is not recommended for sun protection
- An individuals inherent ability to tan and the
ease with which they burn are described as their
skin type
- After UV exposure, skin pigment undergoes two
changes immediate pigment darkening (IPD,
Meirowsky phenomenon) and delayed melanogenesis - IPD is maximal immediately after sun exposure(it
results from changes in melanin already in the
skin) - IPD occurs after exposure to long-wave UVB, UVA,
and visible light - Large doses of UVA produce initial prolonged
darkening
61- TX-
- Prostaglandins are important mediators of sunburn
(ASA or Indomethacin) - Cool compresses
- Sunburn victim experiences at least 1-2 days of
discomfort and even pain before much relief
occurs - Topical remedy
- Indomethacin 100 mg
- Absolute ethanol 57 ml
- Proplene glycol
- Sig spread widely over burned area with palms
and let dry
- Skin type is useful to determine the starting
dose of phototherapy, suncreen recommendations,
and reflects the risk of skin cancer - Exposure to UVB and UVA causes an increase in
epidermal thickness, especially of the stratum
corneum, leading to increased tolerance to
further solar radiation
62Skin Types
63Second-degree sunburn
64Prophylaxis
- Avoid sun exposure between 10 am and 2 pm
- Barrier protection with hats and clothing
- Avoidance plus physical barriers can virtually
always prevent sunburn - Suncreen agents include UV-absorbing chemicals
and UV-scattering or blocking agents(physical
sunscreens)
- Use of the UV index, published daily by the
National Weather Service for many US cities - Sun protection factor-the ratio of the number of
MEDs of radiation required to induce erythema
through a thin film of sunscreen, compared with
unprotected skin
65Sunscreens
- Chemical suncreens-para-aminobenzoic acid(PABA),
PABA esters, cinnamates,salicylates,
anthranilates, benzophenoes) - Physical agents-titanium dioxide
- Combinations of the two
- Water resistant-maintaining their SPF after 40
minutes of water immersion - Water proof-maintating their SPF after 80 mins of
water immersion - UVA protection- sunscreens containing
benzophenones or dibenzoylmethanes - Apply sunscreen at least 20mins before sun
exposure
66Ephelis (Freckle)
- Small (lt0.5cm) brown macules occuring on
sun-exposed skin of face, neck,shoulders,backs of
hands - Become prominent during summer when exposed to
sunlight and subside in winter - Blondes and redheads, with blue eyes, of Celtic
origin (skin types I or II) are especially
susceptible - May be genetically determined
- May occur in successive generations in similar
locations and patterns - Usually appear around age five
- Must be differentiated from lentigo simplex
- LS- a benign discrete hyperpigmented macule
appearing at any age and on any part of the body,
including mucosa - Intensity of color is independent of sun exposure
67Ephelis
- Solar lentigo (frequently misnamed liver spot)
appears at at a later age, mostly in persons with
long-term sun exposure - Favored sites are backs of hands and face
- Histologically, the ephelis shows increased
production of melanin pigment by a normal number
of melanocytes - Otherwise epidermis is normal
- Lentigo has elongated rete ridges that appear
club shaped
68Photoaging(Dermatohelioisis)
- Characteristic changes induced by chronic sun
exposure - AKA photoaging or dermatoheliosis
- Risk of developing these changes correlated with
baseline pigmentation(constitutive pigmentation)
and abilitiy to resist burning and tan following
sun exposure(facultative pigmentation) - Individuals can be divided into six skin types(or
phototypes) - Risk for melanoma and nonmelanoma is also related
to these skin types
69- Most susceptible to effects of sunlight are those
of skin type I-blue-eyed, fair-complexioned
persons who do not tan - These pts require more frequent and careful skin
exams - Many of the changes of chronic sun exposure were
formerly ascribed to chronic aging - Primary sites involved are
- V area of neck and chest, back, and sides of
neck,face, backs of hands and extensor arms
- Skin becomes atrophic, scaly, wrinled, inelastic.
Or leathery with a yellow hue (Milians citrine
skin) - In some pts of Celtic ancestry, dermatoheliosiis
produces profound atrophy without wrinkling,
resulting in an almost translucent appearance of
skin through which hyperplastic sebaceous glands
and prominent telangiectasias are seen - These people are at high risk for nonmelanoma
cancer
70Dermatoheliosis
- Solar elastosis(actinic)
- Caused by alterations in upper dermal elastic
tissue and collagen - Imparts a yellow color to skin
- A textural and tinctorial change in sun-damaged
skin
- Striated beaded lines- are small yellowish
papules and plaques developing along the sides of
the neck - These are a result of sebaceous hyperplasia
- Fibroelastolytic papulosis of the
neck(psuedoxanthoma elasticum-like papillary
dermal elastolysis
71Dermatoheliosis
- On the face or chest a macroscopic, translucent
papule with a pearly color resembling a basal
cell carcinoma may occur - This is Dubreuilhs elastoma, actinic elastic
plaque - Similar plaques may occur on the helix or
antihelix of ear
72Dermatoheliosis
- Poikiloderma of Civatte-refers to reticulate
hyperpigmentation with telangiectasia, and slight
atrophy of sides of the neck, lower anterior neck
and V of neck, and V of chest - Submental area is spared
- frequently presents in fair-skinned men and women
in their middle to late thirties or early forties
73Dermatoelastosis
- Cutis rhomboidalis nuchae (sailors neck or
farmers neck) is characteristic of long-term,
chronic sun exposure - Skin on back of neck becomes thickened, tough,
and leathery and normal skin marking become
exaggerated
74Dermatoheliosis
- Nodular elastoidosis with cysts and comedomes
occurs on the inferior periorbital and malar
skin-Favre-Racouchot syndrome or on the forearms
(actinic comedonal plaque) - Both consist of thickened yellow plaques studded
with comedomes and cystic lesions - Tx-removal , retinoic acid cream, surgical
removal of cysts and redundant skin
75- Telangistasias over cheeks, ears, and sides of
neck may develop - Due to damage to connective tissue of dermis,
skin fragility is prominent, and pts note skin
tearing with minimal trauma - Especially to extensor surface of arms leading to
an ecchymosis, called actinic purpura - As ecchymoses resolve, dusky brown macules remain
for months, increasing mottled appearance of skin
- White stellate pseudoscars on forearms are a
frequent complication of this enhanced skin
fragility - Some pts develop soft, flesh-colored to yellow
papules and nodules that coalesce on the forearms
to form cordlike bands extending from the dorsal
to the flexural surfaces- solar elastotic bands
76Solar Elastosis
- Histologically, chronically sun-exposed skin
demonstrates homogenization and a faint blue
color of connective tissue of the upper reticular
dermis, so-called solar elastosis - The elastotic material is derived from elastic
fibers mainly - Characteristically there is a zone of normal
connective tissue below the epidermis
77Adult Onset Colloid Milium
- Translucent, flesh-colored, or slightly yellow 1-
to 2-mm papules on sun exposed areas of hands,
face, neck, ears in middle-aged adults - Refinery workers and persons using
high-concentration hydroquinone creams may also
develop colloid degeneration - Histologically, homogenous, fissured masses
occupy the upper dermis, resembling amyloid
78Photosensitivity
- Phototoxicity may occur from both externally
applied (phytophotodermatitis and berloque
dermatitis) or internally administered chemicals
(phototoxic drug reaction) - Or by external contact- (photoallergic contact
dermatitis) - In the case of external contactants
phototoxicity occurs on initial exposure, has
onset lt 48 hrs, occurs in most people exposed
to the phototoxic substance and sunlight
- Chemically induced many substances known as
photosensitizers may induce an abnormal reaction
in skin exposed to sunlight or its equivalent - Substances may be delivered externally (by
contact) or internally by enteral or parenteral
administration - Resulting in a markedly increased sunburn
response without prior allergic sensitization
called phototoxicity
79- Photoallergy, in contrast, occurs only in
sensitized persons, may have delayed onset, up to
14 days( a period of sensitization), and shows
histologic features of contact dermatitis - Chemicals known to cause photosensitivity
(photosensitizers) are usually resonating
compounds with a molecular weight of lt 500 - Absorption of radiant energy (sunlight) by the
photosensitizer produces an excited state
- When returning from returning from an excited
state to a lower energy state gives off energy
through fluorescence, phosphorescence, charge
transfer, heat, or formation of free radicals - Each photosensitizing substance absorbs only a
specific wavelengths of light called its
absorption spectrum - Action spectrum-specific wavelength of light that
evokes a photosensitive reaction
80- Action potential for photoallergy is mostly in
the long ultraviolet (UVA) region and may extend
into the visible light region (320 to 425 nm) - Photosensitivity reactions occur only when there
is sufficient concentrations of the
photosensitizer in skin, and the skin is exposed
to a sufficient intensity and duration of light
in the action spectrum of that photosensitizer
- The intensity of the photosensitivity reaction is
dose dependent and is worse with a greater dose
of photosensitizer and greater light exposure
81Photosensitivity
- Drug-induced photosensivity-photoallergic
dermatitis on sun-exposed areas of an infant
following topical use of hexachlorophene
82Photoallergic dermatits
- Papulovesicular lesions of photoallergic
dermatitis due to hexachlorophene
83Phytophotosensitivity
- Plant-induced photosensitivity-linear
hyperpigmentation on the face of a child
following exposure to limes and sunlight
84Phytophotosensitivity
- Hyperpigmentation on the dorsal aspect of the
hands following the use of limes and sunlight
exposure
85Phototoxic Reactions
- A nonimmunologic reaction developing after
exposure to a specific wavelength and intensity
of light in the presence of a photosensitizing
substance - A sunburn-type reaction(erythema, tenderness, and
blistering) - Can occur in pts without prior history of
exposure to that particular substance
- Erythema begins (like sunburn) after 2-6 hrs and
worsens for 48-96 hrs before beginning to subside - Exposure of the nail bed may lead to onycholysis,
called photo-onycholysis - Phototoxic ractions may cause hyperpigmentation,
even without preceding erythema - The action spectrum for most phototoxic reactions
is in the UVA range
86Phototoxic Tar Dermatitis
- Persons with type V and VI skin are protected
from this - Up to 70 of whites exposed to such combinations
will develop this - Hyperpigmentation occurs, and may persist for
years - Coal tar or its derivatives may be found in
cosmetics, drugs, dyes, insecticides, and
disinfectants
- Coal tar, creosote, crude coal tar, or pitch, in
conjunction with sunlight exposure, may induce a
sunburn reaction associated with a severe burning
sensation - Direct contact may not be needed, since these
hydrocarbons are airborn - Burning and erythema may continue for 1 3 days
87- When furocoumarins in many plants may cause a
phototoxic reaction when these plants come in
contact with moist skin exposed to UVA light - Several hrs after exposure, a burning erythema
occurs, followed by edema and development of
vesicles or bullae - Intense hyperpigmenation occurs that may persist
for weeks or months - Tx-similar to tx of sunburn hyperpigmentation-tim
e
- Phytophotodermatits from squeezing limes
88Berloque Dermatitis
- Characterized by lavaliere(hanging drop)-shaped
pigmented patches - Word for pendant in French is berloque, and in
German is berlocke - Seen most frequently on sides of neck, and
retroauricular area in women - In men usually beard area caused by aftershave
lotion - Chief cause-oil of bergamount, containing a
furocoumarin (bergapten)
89Photosensitivity in Tattoos
- Yellow cadmium sulfide may be used as a yellow
dye or may be incorporated into red mercuric
sulfide pigment to produce a brighter red color
for tattooing - When exposed to 380, 400, and 450 nm wavelengths
of light, these areas in tattoos may swell,
develop erythema, and become verrucose - If occurs, either the tattooed person must avoid
sunlight exposure
90Phototoxic Drug Reactions
- Most occur from tetracyclines, nonsteroidal
antiinflammatory drugs, amiodarone, and
phenothiazines - Action spectrum for all is in the UVA range
- Among the NSAIDs, piroxicam is the most potent
photosensitizer - Among the tetracycline group, demthylchlortetracyc
line and doxycycline are most phototoxic
- In the case of amiodarone and chlorpromazine,
while typical phototoxic reactions (resembling
sunburn) may occur, hyperpigmentation is a
well-recognized pattern of phototoxicity - It causes slate blue(amiodarone) or slate gray
(chlorpromazine) coloration, resulting from drug
deposition in the tissues
91Drug induced photosensitivity
- The erythema is less apparent in black skin, but
the involvement of the nose in this patient
suggests phototoxicity, in this case caused by
thiazide
92Drug-induced photosensitivity
- Not only the nose was but also the V of the
neck which was highly suggestive of phototoxicity - Same pt
93Drug-induced photosensitivity
- There is erythema and edema on the exposed sites,
the V of the neck . - This distribution would suggest the diagnosis
94Drug induced photosensitivity
- The backs of the hands are the classic sites to
be involved in light induced eruption - Same pt
95Photoallergy
- Over time lichenification develops, leading to
thick plaques - Face, hands, neck, forearms are most frequently
involved - Over time the dermatitis develops to sunprotected
skin - Removal of offending agent may not lead to
complete resolution of the photoallergic
reaction-referred to as a persistent light
reaction - Clinical and path findings are similar to those
of allergic contact dermatitis
- Photoallergic dermatitis is caused by a
photosensitizing substance plus sunlight exposure
in a sensitized person - If photosensitizer is delivered internally, it is
called a photoallergic drug reaction - If it comes to the skin externally, is is called
a photoallergic contact dermatitis - Clinically the pt develops a pruritic eruption,
initially on sun-exposed areas
96- Phototoxic reaction to a nonsteroidal
antiinflammatory drug
97- Photoallergic dermatitis on sun-exposed areas
98Photoallergy Testing
- Practical office procedure is that each of the
suspected photosensitizers is applied in
duplicate to two symmetrical sites on the back
that have not been exposed to sunlight - Usual concentration used for the patch test is 1
petrolatum - After 48 hrs, one set is removed and examined for
reactions as a contactant without exposure to
light - Then the site is exposed to UVA
- After another 48 hrs, the irradiated site is
compared with the other patch test site
(unexposed site) - When both sides are positive, there is a contact
sensitivity or photoallergy - When the irradiated site alone is positive ther
is only photoallergy - When the irradiated site is more positive than
the unirradiated site, ther is both allergic
contact and phototcontact dermatitis
99Treatment
- Both acute and chronic photosensitivity are
treated similarly to any other inflammatory
dermatitis, with topical corticosteroids
100Polymorphous Light Eruption
- The papular (or erythmatopapular) variant is the
most common, but papulovesicular, eczematous,
erythematous and plaquelike lesions also occur - Lesions occur 1-4 days after exposure to sunlight
- Pts report itching and erythema within the first
24 hrs - A change in the amount of radiation is important
- Most common form of sensitivity
- All races and skin types affected
- Typically in first three decades
- Females outnumber males
- Unknown pathogenesis
- Positive family history in 10-50 of pts
- Different morphologies seen, although in the
individual the morphology is constant
101PLE
- Pts living in the tropics are free of eruption
but may develop disease when they move to
temperate zones - Most commonly involved areas are chest, face,
neck, and arms - Typically areas protected during the winter, as
the extensor surface of the forearms, are
particularly affected, whereas areas exposed all
year (face and dorsa of hands) may be relatively
spared - Eruption appears in springtime commonly
- PLE is induced by UV light, but the wavelengths
responsible varies - Visible light does not induce PLE
- Standard phototesting usually does not induce an
abnormal response in pts - If an abnormal response occurs it is only
erythema - Provocation testing with repeated exposures may
be required - Two unusual variants of PLE are juvenile spring
eruption of the ears and solar purpura
102PML
- Exposed areas such as the backs of the hands and
forearms are affected. Ultraviolet A is mainly
responsible and may penetrate window glass
103PML
- The patchiness of the edematous papules and
plaques is characteristic
104PML
- The eruption is less red and confluent than a
sunburn
105PML
- The lesions are typically papular and clustered
106PML-pathology
- Characteristic perivascular mononuclear cell
infiltration
107PML
- Very itchy, red,edematous papules, which may
coalesce into plaques, occur 1 or 2 days after
exposure to light
108PML
- This young women developed a widespread pruritic,
papular eruption after using a sunbed, which
emitted ultraviolet A
109Juvenile springeruption
- Solar purpura-rare variant of PLE, presenting as
macular or palpable purpura on the legs - It is also UVA induced, but its distribution
suggests other factors asuch as high hydrostatic
pressure are required - Therapeuticallysunscreen, avoiding sun, topical
steroids for itch and clearing eruption,
antihistamines, systemic steroids,
hydroxtchloroquine sulfate, chloroquine, PUVA,
thalidomide, Azathioprine
- Most common in boys ages 5-12 yrs
- Presents in spring with grouped s,all papules or
papulovesicles on the helices - It is self-limited and does not scar
- UVA is the inducing spectrum and some pts have
PLE lesions elsewhere
110PML
- Polymorphous light eruption erythematous
papulovesicular and plaque-like lesions with
characteristic distribution on the sun-exposed
areas of the cheek
111Actinic Prurigo
- In children the cheeks, distal nose, ears, and
lower lip are involved - Cheilitis may be the initial and only feature for
years - Conjunctivitis is seen in 10-20 of pts
- Lesions of arms and legs are also common but
usually exhibit a prurigo nodule configuration - May extend and involve sun-protected areas,
especiall buttocks - In adults dry papules and plaques are typical,
cheilitis and crusting occur less frequently
- Variant of PLE
- Most common in Native Americans of North and
Central America and Colombia - More common in females
- Begins before age 10 in 45 of cases and before
age 20 in 72 of Native Americans - Up to 75 have a family history
- In childhood begins as small papules or
papulovesicles that crust and become
impetiginized - Intensely pruritic
112Actinic Prurigo
- In temperate and high-latitude regions, lesions
occur from March through the summer and remit in
winter - In tropics lesions tend to last all yr
- Hardening as seen with PLE does not occur
- Up to 60 of pts with actinic prurigo that
present before age 20 have resolution within 5
yrs - Adults, however continue with disease all through
life
- IgE levels may be elevated
- Pts are more commonly positive for HLA-A24 and
Cw4 and neg for A3 than are control pts - Tx same as PLE
- Thalidomide has been used extensively with
excellent results
113Actinic Prurigo
- The clinical features are somewhat suggestive of
PML, but the lesions are persistent and the HLA
type was DR4( occurs in 80-90 of AP pts)
114AP
115Actinic prurigo
- Actinic prurigo in Native American brothers
116Actinic prurigo
- Actinic prurigo in Native American boy
117AP-pathology
- Early lesions have variable acanthosis and
spongiosis of the epidermis with an underlying
perivascular mononuclear cell infiltrate with
edema - Later lesions show crusts, increasing acanthosis
and variable lichenification plus a heavy
infiltrate of mononuclear cells, leading to a
non-specific picture(as seen here)
118Solar Urticaria
- Wavelengths of sensitivity may vary with anatomic
location and over time with same pt - Leenutaphong et al divided SU into two typesType
I the photoallergen precursor is an abnormal
endogenous substance in type II it is a normal
skin component - Type I SU has an action spectrum in visible
range type II has a variable action spectrum - Ddx-SLE
- Most common in females aged 20-40
- Within seconds to mins after light exposure,
typical urticarial lesions appear and resolve in
1-2 hrs - Delayed reactions may rarely occur
- In severe attacks syncope, bronchospasm, and
anaphylaxis may occur - Pts with SU are sensitive to wavwlenghs of light
from UVB-visible light
119Solar Urticaria
- Sunlight-induced whealing with surrounding
erythema of the abdomen
120SU
- Phototesting is useful in SU to determine the
wavelengths of sensitivity - Lasers and natural sunlight may be used to elicit
positive reactions - Many pts have a sensitivity in the UVA or even
visible range, standard sunscreens are of limited
benefit - Antihistamines and sun avoidance are first line tx
- Doxepin may be added if these are not effective
- Antimalarials can help in some pts
- PUVA or increasing UVA exposures are effective
in more difficult cases - Plasmapheresis may be used to remove the
circulating photoallergen, allowing PUVA to be
given leading to remission
121Hydroa Vacciniforme
- Photodermatosis with onset in childhood
- Lesions appear in crops with disease free
intervals - Attacks may be preceded by fever and malaise
- Ears, nose, cheeks, and extensor arms and hands
are affected - Within 6 hrs of exposure stinging may occur
- At 24 hrs or sooner erythema and edema appear,
followed by vesicles
- Over a few days the lesions rupture, becoming
centrally necrotic, and heal with a smallpoxlike
scar - Lesions may bebome confluent, forming bullae, and
recurrent disease may lead to contractures of
digits - Conjunctivitis with photophobia may occur and
corneal ulcers and opacities may result - Natural history is improvement by second decade
often complete resolution
122HV
- Hydroa vacciniforme-the face was also involved
123Hydroa Vacciniforme
- There is an early, PML-like eruption, but with
vesicles around the mouth and umbilicated lesions
on the nose
124Hydroa Vacciniforme
- A later, more severe example shows vesiculation
with umbilication, but also marked hemorrhagic
crusting
125Hydroa Vacciniforme
- A severe example of the typical vacciniform
facial scarring that may develop following
repeated acute attacks
126HV
- Ddx-PLE, actinic prurigo, and erythropoietic
protoporphyria (EPP) - Porphyrin levels are normal in hydroa
vacciniforme - In EPP the burning typically begins within mins
of sun exposure, and healing is diffuse,
thickened, wax-like scarring, rather than the
smallpox-like scars of hydroa vacciniforme - Histology is helpful in differentiating between
the two
- Tx-avoid sunlight exposure, use broad-spectrum or
barrier sunscreens that block UVA range - Hydroxychloroquine and prophylactic PUVA may be
partially effective
127Chronic Actinic Dermatitis
- A disease concept in evolution
- Previously known as persitent light reactivity,
actinic reticuloid, photosensitive eczema and
chronic photosensitivity dermatitis - Basic components area persistent, chronic,
eczematous eruption in absence of exposure to
known photosensitizers decreased MED to UVA,
and/or UVB, and visible light
- Disease affects middle-aged or elderly men
- In US skin types V and VI more affected
- Skin lesions are edematous, scaling, thickened
patches and plaques that become confluent - Lesions occur on most sun-exposed skin
128Chronic Actinic Dermatitis
129Therapy
- Danazol 600mg daily was effective in one pt
- Hydroxychloroquine may be added to systemic
steroids or azathioprine - Low-dose PUVA is bebficial but may not be
tolerated - Cyclosporine is tx of last resort but is
effective in severe cases (it is associated with
acute and chronic toxicity and relapse occurs
rapidly after discontinuation
- Difficult-possible topical photosensitizers
should be identified via photopatch testing - Maximum sun avoidance and broad-spectrum
sunscreens - Topical and systemic steroids are effective in
some cases - Azathioprine, 50 to 200 mg/day(most reproducibly
effective tx), may be required annually during
periods of increased sun exposure
130Dermatoses with Photoexacerbation or
Photosensitivity
- Pts with lupus erythematosus and dermatomyositis,
among other connective tissue diseases, often
exhibit photosensitivity - Moa may be UV alteration of cellular cytoplasmic
or nuclear antigen expression, allowing antigens
to interact with circulating autoantibodies - Pts with diseases characterized by a deficiency
of protective pigmentation are photosensitive(albi
nism, vitiligo)
- Heritable disorders with increased sensitivity to
ultraviolet cellular or DNA damage such as
xeroderma pigmentosum, Bloom syndrome, and
Cockaynes disease - Disease where ultraviolet light seems to act by a
Koebners phenomenon- Dariers, and perhaps
pemphigus foliacus
131Radiodermatitis
- Major target within the cell is DNA
- Effects depend on the amount, its
intensity(exposure rate), and characteristics of
the individual cells - Rapidly reproducing cells and anaplastic cells
have increased photosensitivity compared to
normal tissue - When radiation is delivered it is
fractionated-divided into small doses called
fractions-allowing normal cells to recover
between doses
- In small amounts effects are insidious and
cumulative - When dose is large, cell death occurs
- With sublethal doses many changes occur-mitosis
is arrested temporarily, with subsequent growth
arrest - Exposure rate affects the number of chromosome
breaks - The more rapid the delivery the greater the
number of chromosome breaks
132Acute Radiodermatitis
- When exposed to a large amount of ionizing
radiation, an acute reaction develops, the extent
of which depends on amount, quality, and duration
of exposure - Such reaction is used in tx of malignancy and in
accidential overexposure - Reaction is manifested by initial erythema,
followed by a second phase of erythema at 3-6
days
- With an erythema dose of ionizing radiation
there is a latent period of up to 24 hrs before
visible erythema develops - Initial erythema lsts 2-3 days but may be
followed by a second phase beginning up to 1 week
after the exposur and lasting up to 1 month
133Acute Radiodermatitis
- Skin develops a dark color that may be mistaken
for hyperpigmention, but that desquamates - This my subside in several weeks to
months(depending on amount of radiation) - Skin which recieves a large amount or radiation
will never return to normal - It will lack adnexal structure, be dry, atrophic,
and smooth, and be hypopigmented or deoigmented
134Chronic Radiodermatitis
- Chronic exposure to suberythema doses of
ionizing radiation over a prolonged period will
produce varying amounts of damage to skin and
underlying skin after a variable latent period of
several months to several decades - Telangiectasia, atrophy, and hypopigmentation
with residual focal increased pigment (freckling)
may appear
135Chronic Radiodermatitis
- Skin becomes dry, thin, smooth, and shiny
- Subcutaneous fibrosis, thickening and binding of
the surface layers to deep tissues may present as
tenser, erythematous plaques 6-12 months after - It may resemble erysipelas or inflammatory mets
- Nails may become striated, brittle, and fragmented
- Capacity to repair is greatly reduced
- This results in ulceration from minor trauma
- Hair becomes brittle and sparse
- In more severe cases these chronic changes are
followed by radiation keratoses and carcinoma
136Radiation Cancer
- SCCs arising in sites of radiation therapy
metastasize more frequently than purely
sun-induced SCCs - In some pts either type of tumor may predominate
- Location plays some role-SCCs are more common on
the arms and hands, whereas BCCs are seen on
lumbosacral area - Other cancers induced by radiation angiosarcoma,
malignant fibrous histiocytoma, sarcomas, and
thyroid carcinoma
- After a latent period averaging 20 30 yrs,
various malignancies may develop - Most frequent are basal cell carcinomas
- Next frequent are squamous cell carcinomas
- These may occur in sites of prior radiation even
without evidence of chronic radiation damage - Sun damage may be additive
137Radiation Cancer
- SCC developing in a chronic radiation ulcer on
the chest
138Callus
- Most problems with calluses is on the soles
- Ill-fitting shoes and orthopedic problems of the
foot caused by aging are some of the etiologies - Padding to relieve pressure, paring of thickened
callus, and the use of keratolytics(40 salicylic
acid plasters) - Lac-Hydrin 12
- Calluses may be softened by moisterizing them
nightly with 2 parts propylene glycol1 water
- Nonpenetrating, circumscribed hyperkeratosis
produced by pressure - Occurs on parts subject to intermittent
pressure(palms, soles, bony prominences of the
joints) - Callus differs from clavus it that a callus has
no penetrating central core and is a more diffuse
thickening - Calluses tend to disappear spontaneously when
pressure is removed
139Clavus(Corns)
- Hard corns have shiny and polished surface
- When upper layers are shaved off, a core is seen
in densest part of lesion - The core causes the dull/boring or
sharp/lancinating pain by pressing on underlying
sensory nerves - Corns arise on sites of friction and pressure,
when these factors are removed they may resolve
- Circumscribed, horny, conical thickenings with
the base on the surface and the apex pointing
inward and pressing on adjacent structures - Two typeshard and soft
- Hardoccur on dorsa of toes or on soles
- Softoccur between toes, softened by macerating
action of sweat
140Corns
- Frequently, a bony spur or exostosis is present
beneath both hard and soft corns of long duration - Soft interdigital corns usually occur in the
fourth interdigital space of the foot - Many times there is an exostosis at the
metatarsal-phalangeal joint causing pressure on
the adjacent toethese are soft, soggy, and
macerated so that they appear white - Tx by simple excision may be effective
141Corns
- Plantar corns can be differentiated from plantar
warts by paring off the surface keratin until
either the pathognomonic elongated dermal
papillae of the wart with its blood vessels, or
the clear horny core of the corn can be
visualized - Ddx also includes porokeratosis plantaris
discreta- a sharply marginated, cone-shaped,
rubbery lesion common beneath the metetarsal heads
142Hard Corn
143Porokeratosis Plantaris Discreta
- Multiple lesions can occur
- Females are affected 3 times as frequently than
men - It is painful
- Frequently confused with a plantar wart or corn
- Keratosis punctata of the palmar creases may be
seen in the creases of the digits of the feet
where it may be mistaken for a corn
144Corns-tx
- Sometimes more feasible to use a salicylic
acid-lactic acid in collodion rather than plaster - Collodion medication is painted on and allowed
to dry each day until cure - Soaking prior to application enhances effect-this
tx especially effective for interdigital soft
corns - Soaking feet in hot water and paring the surface
by means of a scalpel blade or pumice stone helps
- Primary-relief of pressure by corrective footwear
- Salicylic acid and dichloroacetic acid
- Careful paring in particular remove central core
- 40 salicylic acid application, remove after
48hrs, remove white macerated skin, and apply new
plaster - Continue until corn is removed
145Surfers Nodules
- Nodules 1 to 3 cm (rarely as much as 5 or 6 cm)
- Sometimes eroded or ulcerated
- Develop on top