Common Pediatrics Rashes
Primary skin lesions
Primary skin lesions
• Macule
A macule is an area of color change less than 1.5 cm diameter. The
surface is smooth.
• Patch
A patch refers to a large area of color change, with smooth surface.
• Papule
Papules are small palpable lesions. The usual definition is that they
are less than 0.5 cm diameter, although some authors allow up to
1.5 cm. They are usually visibly raised above the skin surface, and
may be solitary or multiple.
• Papules may be sessile, pedunculated, filiform, or verrucous.
Primary skin lesions
• Plaque
A plaque is a palpable flat lesion greater than 0.5 cm diameter. Most
plaques are elevated, but a plaque can also be a thickened area
without being visibly raised above the skin surface.
• Nodule
A nodule is an enlargement of a papule in three dimensions (height,
width, length).
• Vesicle
Vesicles are small blisters less than 0.5cm diameter. They are fluidfilled papules, and may be single or multiple.
• Pustule
A pustule is a purulent vesicle. It is filled with neutrophils, and may
be white, or yellow. Not all pustules are infected.
Primary skin lesions
• Bulla
A bulla is a large fluid-filled blister. It may be a single compartment
or multiloculated.
• Wheal
A wheal is an edematous papule or plaque caused by swelling in the
dermis. Whealing often indicates urticaria.
• Purpura
Purpura is bleeding into the skin. This may be as petechiae (small
red or brown spots), or as ecchymoses (bruises).
• Telangiectasia
Telangiectasia is the name given to prominent cutaneous blood
vessels.
Secondary skin lesions
• Scaling
Scaling is an increase in the dead cells on the surface of the skin
(stratum corneum). The scale can be psoriatic-type (large white or
silver flakes), pityriasis-type (branny powdery scale), or lichenoid
(tightly adherent to skin surface).
• Lichenification
Lichenification is caused by chronic rubbing which results in
palpably thickened skin with increased skin markings and lichenoid
scale. It occurs in chronic eczema eg. atopic dermatitis or lichen
simplex.
• Exfoliation
Exfoliation is the stratum corneum peeling off, usually occurring after
acute inflammation.
Secondary skin lesions
• Crusting
Crust occurs when plasma exudes through an eroded epidermis. It
is rough on the surface and is yellow or brown in color. Bloody crust
appears red, purple or black.
• Excoriation
An excoriation is a scratch mark. It may be a linear erosion or a
picked scratch. Excoriations may occur in the absence of a primary
dermatosis.
• Erosion
An erosion is caused by loss of the surface of a skin lesion, it is a
shallow moist or crusted lesion.
Secondary skin lesions
• Fissure
A fissure is a thin crack within epidermis or epithelium, and is due to
excessive dryness.
• Ulcer
An ulcer is full thickness loss of epidermis or epithelium. It may be
covered with a dark-colured crust called an eschar.
• Erythroderma
Erythroderma is a term used to indicate red skin over the entire
body.
• A 10-year-old girl with atopic dermatitis
reports itching that has recently become
relentless, resulting in sleep loss. Her mother
has been reluctant to treat the girl with
topical corticosteroids, because she was told
that they damage the skin, but she is
exhausted and wants relief for her child.
•
•
•
•
1. What is atopic dermatitis?
2. What causes it?
3. What questions would you ask the parent?
4. How should the problem be managed?
Atopic dermatitis
clustered lichenified
follicular papules
Atopic dermatitis
Scaly erythematous plaque
Atopic dermatitis
uniform symmetric 2
mm hypopigmented
follicular papules
Atopic dermatitis
symmetric lichenified scaly red plaques
Atopic dermatitis
symmetric red scaly
crusted excoriated
plaques
Atopic dermatitis
symmetric red scaly crusted
excoriated plaques
Atopic dermatitis
acute red edematous annular
scaly and crusted plaques
TOPICAL CORTICOSTEROID POTENCY
Generic name -> Trade name and strength
Class 1--superpotent
Betamethasone dipropionate = Diprolene gel/ointment, 0.05%; Diflorasone diacetate = Psorcon ointment, 0.05%
Clobetasol propionate = Temovate cream/ointment, 0.05%; Halobetasol propionate = Ultravate cream/ointment, 0.05%
Class 2--potent
Mometasone furoate = Elocon ointment, 0.1%; Amcinonide = Cyclocort ointment, 0.1%;
Betamethasone dipropionate = Diprosone ointment, 0.05%; Desoximetasone = Topicort cream/ointment, 0.25%; gel
0.05%; Fluocinonide = Lidex cream/ointment, 0.05%; Halcinonide = Halog cream, 0.1%
Class 3--upper mid-strength
Betamethasone dipropionate = Diprosone cream, 0.05% Betamethasone valerate = Valisone ointment, 0.1% Diflorasone
diacetate = Florone, Maxiflor creams, 0.05% Triamcinolone acetonide = Aristocort cream, 0.5%
Fluticasone propionate = Cutivate ointment, 0.05%
Class 4--mid-strength
Mometasone furoate = Elocon cream, 0.1%; Desoximetasone = Topicort LP cream, 0.05%;
Fluocinolone acetonide = Synalar-HP cream, 0.2%; Synalar ointment, 0.025%;
Flurandrenolide = Cordran ointment, 0.05%; Triamcinolone acetonide = Aristocort, Kenalog ointments, 0.1%
Class 5--lower mid-strength
Betamethasone dipropionate = Diprosone lotion, 0.05%; Betamethasone valerate = Valisone cream/lotion, 0.1%
Fluocinolone acetonide = Synalar cream, 0.025%; Flurandrenolide = Cordran cream, 0.05%;
Hydrocortisone butyrate = Locoid cream, 0.1%; Hydrocortisone valerate = Westcort cream, 0.2%; Prednicarbate =
Dermatop emollient cream, 0.1%; Triamcinolone acetonide = Kenalog cream/lotion, 0.1%; Fluticasone propionate =
Cutivate cream, 0.05%
Class 6--mild
Alclometasone dipropionate = Aclovate cream/ointment, 0.05%; Triamcinolone acetonide = Aristocort cream, 0.1%;
Desonide = DesOwen cream, 0.05%,Tridesilon cream, 0.05%
Fluocinolone acetonide = Synalar cream/solution, 0.01%; Betamethasone valerate= Valisone lotion, 0.1%
Class 7--least potent
Hydrocortisone (0.5, 1.0, 2.5%) = Cortaid, Cortizone 10 (OTC), 2.5% (Hytone) is Rx only
• A 3-month-old girl developed an
asymptomatic scaly red eruption in the
diaper area and the face. The lesions in the
diaper area were well circumscribed and redorange in color.
• 1. What is the rash?
• 2. What causes it?
• 3. How do you manage it?
Seborrheic dermatitis
symmetric red scaly confluent plaques
Seborrheic dermatitis
symmetric red scaly
confluent plaques
Seborrheic dermatitis
symmetric red greasy scaly patches
Seborrheic dermatitis
thick tenacious scale with crust
and underlying erythema
Seborrheic dermatitis
confluent red papules
extending from the creases
• A 6-month-old boy presents with a diaper
rash consisting of confluent, bright red
papules and plaques with scattered pustules,
overlying scale, and satellite lesions at the
periphery.
• 1. What is the rash?
• 2. What causes it?
• 3. How do you manage it?
Candidal Diaper dermatitis
confluent bright red papules and plaques
with scattered pustules, overlying scale,
and satellite lesions at the periphery
• A mother describes to you a diaper rash that
cleared rapidly with frequent application of a
barrier paste and air drying after diaper
changes. She wants to know why this
happens.
• 1. What is the cause of this rash?
• 2. How do you manage it?
Irritant/Contact diaper dermatitis
symmetric uniform 2-3 mm red eroded papules
• A 2-month-old healthy boy developed a
pustular eruption in the diaper area 2 days
ago. A Gram stain showed neutrophils and
Gram positive cocci.
• 1. What is the rash?
• 2. What causes it?
• 3. How do you treat it?
Staphylococcal pustulosis
3-5 mm pustules, some ruptured
and drying with a collarette of scale
• A 10-year-old boy developed asymptomatic
relapsing and remitting hypopigmented
minimally scaly patches on his facial cheeks.
• 1. What is the rash?
• 2. What causes it?
• 3. How do you manage it?
Pityriasis alba
hypopigmented patch with fine scale
• A healthy adolescent developed a large scaly
red patch on the back followed a week later
by a widespread papulosquamous eruption.
The lesions were primarily truncal and only
minimally pruritic.
• 1. What is the rash?
• 2. What causes it?
• 3. How do you mange it and what is the
expected outcome?
Pityriasis rosea
symmetric oval 0.5-3.0 cm
red patches with central
trailing scale
Pityriasis rosea
multiple widespread
round to oval 1-3
cm almost confluent
plaques
• An 18-year-old boy was evaluated for facial
acne. He had multiple open and closed
comedones and a few red papules and
pustules on his malar and temporal areas.
• 1. What causes acne vulgaris?
• 2. What are the different types?
• 3. How do you manage it?
Acne vulgaris
open and closed comedones
Acne vulgaris
symmetric grouped uniform 2 mm
papules with a central dark scaly core
Acne vulgaris
multiple symmetric deep
tender nodules, violaceous
cysts, pustules, and
comedones. BEFORE Rx
(isotretinoin)
Acne vulgaris
symmetric grouped uniform 2 mm
papules with a central dark scaly core.
AFTER
• A 17-year-old boy complained of dry scaly
sandpaper like papules on the extensor
surfaces of his upper arms and thighs for as
long as he could remember. His father had
similar lesions.
• 1. What is the rash?
• 2. What causes it?
• 3. How do you manage it?
Keratosis pilaris
symmetric sandpaper like follicular papules
Keratosis pilaris
symmetric red sand paperlike follicular papules
• An 8-year-old boy demonstrated an annular
scaly plaque on the neck extending into the
scalp with broken hairs and a prominent
right occipital lymph node.
• 1. What is the rash?
• 2. What causes it?
• 3. How do you treat it?
Tinea capitis
annular scaly plaque with occipital
adenopathy
Tinea capitis
ID reaction / autoeczematization / Tinea capitis
patches of scale and erythema over
neck and trunk with pruritic pustules
Tinea capitis / kerion
boggy occipital area
ID reaction
• A 10-year-old boy developed an expanding
annular plaque on the anterior neck. A
potassium hydroxide preparation showed
branching hyphae.
• 1. What is the rash?
• 2. What causes it?
• 3. How do you treat it?
Tinea corporis
concentric red scaly annular plaques
• A 16-year-old soccer player complained of
intense itching and burning in the groin for
one week. He attributed the rash to playing
matches in the rain for the preceding two
weeks.
• 1. What is the rash?
• 2. What causes it?
• 3. How do you treat it?
Tinea cruris
Erythematous,
hyperpigmented
scaly plaques
centered on the
inguinal creases and
extending down the
medial thighs
• A 20-year-old man had an extensive itchy
rash involving the soles, undersurfaces of
the toes, and web spaces of both feet.
• 1. What is the rash?
• 2. What causes it?
• 3. How do you treat it?
• An 8-year-old girl was evaluated for multiple
hypopigmented macules on her face. A
potassium hydroxide preparation made from
a scraping of fine scale from the macules
showed pseudohyphae and spores.
• 1. What is the rash?
• 2. What causes it?
• 3. How do you treat it?
Pityriasis versicolor
Well-demarcated
hypopigmented
macules with
minimal scale
Pityriasis versicolor
Pityriasis versicolor
Red macules
White macules
Brown macules
Hyphae and spores
• An otherwise-healthy 6-year-old boy
presents for evaluation of multiple papules
on his arms, legs, and trunk. He has
developed over 50 of these lesions, which
are asymptomatic, over the last 4-5 months.
• 1. What is the most likely etiology?
• 2. What causes it?
• 3. How do you treat it?
Molluscum contagiosum
pearly 3-4mm papules, some with a central dell
Molluscum contagiosum
5 mm pearly papule with central white scale
• A 9-year-old healthy boy developed
persistent warts on his hands that spread to
his upper lip and hard palate.
• 1. What are the different types of warts?
• 2. What is the etiology?
• 3. What are his treatment options?
Warts
multiple 1-3 mm rough topped papules
Warts
1 cm eroded rough brown
papule with central crust
and hemorrhage
• A 19-year-old notes diffuse, intense itching.
He reports that his girlfriend has the same
itching. Examination of the skin reveals
interdigital lesions, with small papules,
vesicles, and excoriations on the hands, and
indurated nodules on the genitalia.
• 1. What is the rash?
• 2. What causes it?
• 3. How do you treat it and what is the expected
outcome?
Scabies
generalized, symmetric, linear
red papules and pustules
Scabies
generalized, symmetric, linear red papules and pustules
Scabies
multiple, symmetric red excoriated
papules, vesicles, and pustules
Scabies
multiple, elongated, excoriated
red edematous papules
Scabies
Scabies mite under scope
• A 7-year-old girl is sent home after the
school nurse detects head lice. She will not
be permitted to return to school until the
absence of infestation is documented.
• 1. What is the technical term for head lice?
• 2. How does it develop?
• 3. What treatment strategy is most likely to allow
her to return to school with a minimal risk of
infecting her classmates, i.e. How do you treat
it?
Pediculosis capitis
excoriated crusts and live crawlers
Pediculosis capitis
nits on hair shafts and fecal
material on the skin above
the ear
Pediculosis capitis
adult female head louse
Pediculosis capitis
viable head louse egg