Neonatal Skin Flashcards
What are the functions of the skin?
- physiologic and immunologic protection
- heat regulation
- sense perception
- self cleaning
What is the top layer of skin?
epidermis
Describe the epidermis.
comprised of 5 layers; stratum corneum is the top layer; made up of dead cells, constantly being replaced
lower layers are comprised of keratin- forming cells and melanocytes
Where is the dermis located and what elements does it contain?
directly under the epidermis; contains fibrous tissue, elastic tissue, sweat glands, sebacceous glands and hair shafts
What is the fx of subcutaneous fat?
- insulation
- protection for internal organs
- calorie storage
How does neonatal skin differ from adult skin?
- less mature = less mature function
- immature infant = thinner, more permeable
- fibrils more fragile
- stratum corneum is thinner
- sweat glands- adult fx by 2-3mo of life
Describe the sweating function in neonates.
limited < 36 week GA, ability increases with postnatal age; sweating on forehead- check for hyperthermia, CHD
What is vernix caseosa?
sebacceous gland secretions and exfoliated skin cells; coats skin until 37-38th wk
What is the differential dx of yellow vernix?
- passage of mec
- hgb break down r/t chronic abruption
- hgb break down r/t hemolytic disease
- chorio
When does lanugo appear and disappear?
starts @ 20 weeks- gone by 40
What might a sacral hair tuft indicate?
a tethered cord
What is a lesion?
area of altered tissue
What is a macule?
discolored, flat spot < 1cm in diameter that is not palpable
What is a patch?
a macule > 1cm in diameter
What is a papule?
an elevated, palpable lesion, solid and circumscribed,
< 1cm in diameter
What is a plaque?
an elevated, palpable lesion with circumscribed borders
> 1 cm or a fusion of several papules
What is a vesicle?
an elevation of the skin filled with serous fluid & < 1cm in diameter; ex: blister
What is a bulla?
vesicle > 1cm in diameter
What are petechiae?
small, purplish hemorrhagic, pin point size point
What are purpura?
small hemorrhagic spot larger than petechiae, 1-3cm in size
What is ecchymosis?
large area of subepidermal hemorrhage- does not blanch; a mogolian spot doesn’t blanch but is differentiated from a bruise because it does not change color over time
What is a pustule?
an elevation of the skin filled with cloudy or purulent fluid
What is a cyst?
raised palpable lesion with fluid or semi soft filled sac; can be drained
What is a nodule?
an elevated palpable lesion with indistinct borders- can palpate below the skin; can NOT be drained; mobile lesion
What is a crust?
a lesion of dried serous exudate, blood or pus
What is a wheal?
a collection of fluid in dermis that appears as a reddened, solid elevation; ex: allergic reaction
What can account for petichae on the neck?
nuchal cord
What factors can influence the findings of a thorough skin exam?
- approach (organized and consistent)
- history
- L&D experience ( forceps, vacuum, nuchal cord, etc)
- environment ( lighting, temp of room, heat source)
How should skin be examined?
1) undress the infant
2) use same pattern of examination
3) start at head and progress downward
4) turn infant to examine the back
5) inspect all skin folds, including axillae & groin
6) inspect color, moisture, thickness & opacity of skin
7) turgor- hydration and nutrition
8) note size, color and placement of any lesions
9) note hair distribution
How should skin be described?
elastic, fragile, good recoil, etcc
What can palpation of the skin reveal?
- examine the underlying dermis
- determine thickness of the skin
- subcutaneous fat
- presence of edema
- irregularities in texture and consistency
- helps to determine skize or configuration of lesions
- blanching- take away coloring by hgb and can observe whats underneath (ex petichae or jaundice)
How should most neonatal lesions be interpreted?
most lesions are benign and transient
Why does harlequin color change appear?
due to immature autonomic nervous system
What is erythema neonatorum?
- generalized hyperemia
- occurs in the first few hours post birth
- resolves in minutes up to one hour
- indicates successful completion of fetal to neonatal circultion
What accounts for an infant with plethora coloring?
- check hematocrit (>65% = polycythemia)
- monitor hypoglycemia and RDS
Why is plethora a risk factor for hypoglycemia?
only fuel for RBCs is glucose; polycythemia monopolizes glucose in the serum
What accounts for an infant with acrocyanotic coloring?
bluish discoloration of hands and feet, present at birth; persists up to 48h of life and is exacerbated by low environmental temp; mucous membranes are pink
What accounts for an infant with circumoral cyanosis coloring?
more pronounced in the first 12-24h after birth; also seen with feeding which resolves after feeding; can be a normal finding in fair infants and is simply the blue color of the veins below the skin in this area
At what level of hgb desaturation for cyanosis to be present?
3-5gm/dL (~ sats of 70%)
What is the correlation between hypoxia and cyanosis?
terms aren’t mutually exclusive; what is important is the concentration of oxygenated hemoglobin
What is jaundice?
yellow coloring of the skin & sclera; deposits of bile pigment in the skin r/t hyperbilirubinemia; pay attention to age of infant & degree of jaundice present
*Always pathologic if seen in 1st 24h
How does jaundice progress in the infant?
general rule: first appears on the face, then progresses to the toes as levels rise; cephalocaudal progression
What is the risk for sick babies and hyperbili?
sick babies permit bili to cross the blood brain barrier much more readily
What does yellow jaundice indicate?
jaundice due to indirect or unconjugated hyperbili
How does the amount of subQ fat influence the presentation of jaundice?
amount of subQ fat influences progression in color; chubby babies don’t appear as jaundiced
What does the appearance of jaundice in the sclera indicate?
deposition in sclera indicates a bili level >10mg/dL
What is the relative serum bili level when an infant’s face is jaundiced?
4.8-8 mg/dL
What is the relative serum bili level when an infant’s chest to the umbilicus are jaundiced?
5.5-12 mg/dL
What is the relative serum bili level when an infant’s groin and thighs are jaundiced?
8-16.5 mg/dL
What is the relative serum bili level when an infant’s legs are jaundiced?
11-18 mg/dL
What is the relative serum bili level when an infant’s palms and soles are jaundiced?
> 15 mg/dL
Why is skin color assessment s/p phototherapy an unreliable assessment?
after being on bili lights, it’s impossible to determine jaundice based on skin color & lights bleach the skin
How does jaundice d/y direct or conjugated hyperbilirubinemia present?
green/ brown; direct bili babies take much longer to correct
What is cutis marmorata?
bluish mottling or marbling of skin
When is cutis marmorata present?
seen in response to chilling, stress or overstimulation caused by dilation of capillaries & vessels; should disappear when infant is warmed; persistent in trisomy 21 & 18
What is the most common newborn benign rash?
erythema toxicum; 30-70% of term infants; rarely seen in preterms
What is the peak incidence of erythema toxicum?
24-48h but can occur up to 3 months of age; duration is typically a few hours to several days; resolves spontaneoulsy
Where can erythema toxicum be found?
found on any part of the body; disappears and reappears moments or hours later on a different body area
What causes erythema toxicum?
cause is unknown; possible immune reaction, possible inflammatory response
How is erythema toxicum diagnosed?
visual recognition
How does erythema toxicum present?
1) urticaria neonatorum “flea bit dermatitis”; small, white or yellow papules or vesicles with an erythematous base
2) vesicular lesions: look like pustules, no inflammation around them
How is erythema toxicum differentiated from herpes?
herpes generally has a more clustered and vesicular appearance; scraping of a lesion can be done and fluid examined under microscope for definitive dx
What will the examination of erythema toxicum scrapings reveal?
erythema toxicum lesions will show eosinophils on gram stain; eosinophils are present in allergic reactions
What will the examination of herpes scrapings reveal?
positive direct fluorescent antibody test; positive Tzanck smear (giant multinucleated cells)
How do herpetic lesions present in the newborn?
- may appear at birth as lesions or eroded skin
- may not appear until day 7-10
- appears virulent; herpes can involve the skin, CNS or dissemenated (CNS & dissemenated may present w/o lesions)
What are milia?
multiple yellow or pearly white papules about 1mm in size
Where are milia usually located?
found on brow, cheeks, nose in up to 40% of newborns; if in mouth = epstein’s pearls or bohn’s nodules (rice like kernels on gums)
What causes milia?
keratin- filled epithelial cysts; resolve spontaneously in first few weeks
What is subaceous gland hyperplasia?
numerous tiny (< 0.5mm) white or yellow papules found on nose, cheeks and upper lip
What causes the appearance of subaceous gland hyperplasia?
maternal androgenic stimulation (testosterone) androgen exposure in utero; spontaneously resolve after birth; no tx req’d
How can milia and subaceous gland hyperplasia be differentiated?
SGH lesions are more yellow in contrast to milia
What is the etiology of milliaria?
obstruction of sweat ducts due to excessively warm, humid environment; sweat ducts are immature and easily obstructed; classified as 1 of 4 types depending on severity
Where do milliaria present?
seen over forehead, on scalp and in skin folds
What is the appearance of Miliaria Crystallina- type I?
clear, thin vesicles, 1-2mm in diameter; no inflammation around them
Where do Miliaria Crystallina develop?
in the epidermal portion of the sweat gland; typically present on the head and chest
How do Milia differ from Miliaria Crystallina?
lesions lack opacity and they appear later
What is the appearance of Miliaria Rubra- type II?
appears as small erythematous papules
What is the etiology of Miliaria Rubra?
prolonged obstruction of the ducts of the sweat glands leading to: 1) release of sweat into adjacent tissue 2) accompanied by prickly sensation
What is the etiology of Miliaria Pustulosa- type III?
progressive occlusion caused by:
1) leukocyte infiltration of papule
2) if not resolved, secondary infection can occur in deeper part of sweat gland
3) leads to Type IV- Miliaria Profunda
How is Miliaria treated?
eliminate source, eliminate extreme heat/ humidity… keep
What are some of the most common pigmented lesions?
1) hyperpigmented macule “mongolian spot”
2) transient neonatal pustular melanosis
3) pigmented nevus
4) cafe au lait patches
In what populations are hyperpigmented macule mongolian spots observed?
90% of AA, Asian & Hispanic infants
10% caucasian
Describe mongolian spots.
grey or blue-green in color; commonly present on buttocks, flanks or shoulders; Document size and location to avoid later suspicion of NAT
What is the etiology of mongolian spots?
melanocytes that infiltrate the dermis; fade over the first 3 years as skin darkens- may persist into adulthood.
What is transient neonatal pustular melanosis?
superficial, vesiculopustular lesions; vesicles rupture in 12-48 hours leaving small pigmented macules; macules are surrounded by very fine white scales; look like pustules, but when lanced are dry inside
When is transient neonatal pustular melanosis alarming?
when present at birth
Where do transient neonatal pustular melanosis typically present?
seen most often in clusters under chin, neck, lower back and extremities; most common in AA babies
What is the long term prognosis for transient neonatal pustular melanosis?
usually regree in 1-2 months; may remain for up to 3 months; hyperpigmented area blends as the surrounding tissue darkens
How do transient neonatal pustular melanosis present on gram stain?
numerous neutrophils
What is the etiology and treatment available for transient neonatal pustular melanosis?
etiology unknown, benign- no treatment is necessary
Describe the pigmented nevus.
dark brown or black macule; commonly present on lower back or buttocks (can occur anywhere)
Why are hairy pigmented nevi concerning?
10% hairy pigmented nevi become malignant melanomas; can become basal cell carcinomas or melanomas
How should pigmented nevus be treated?
generally benign- malignant changes can occur in up to 10% of infants; observe closely for changes in size and shape
What is the potential progression of a hairy pigmented nevus?
pigmentation increases in 1st year> plastic surgery by 5 years of age > risk of cancer as an adult
What percentage of multiple pigmented nevi are malignant?
10-15%
What is concerning about the neurocutaneous melanosis sequence?
can be a/w sz and mental deterioration
What is the typical presentation of junctional nevus?
flat, superficial; excessive melanocytes at dermal- epidermal junction; usually benign if present at birth
What changes occur with a sebaceous nevus during puberty?
become larger d/t sensitivity to andrgoens and become more wart like; carry an increased risk of becoming malignant
What is an epidermal nevus?
proliferations of the epidermis and papillary dermis; usually unilateral following Blaschko lines in linear configurations on limbs
What are Blaschko lines?
skin lines are invisible under normal condition; believed to trace embryonic skin cell migration
What other anomalies are epidermal nevus associated with?
CNS, bone and eye anomalies, more likely in those with extensive lesions
Describe cafe as lait patches.
tan or light brown macules or patches with well defined borders; 19% of normal children have one; it is common to have 1-3
What are the implications of cafe au lait patches?
when < 3 cm in length & < 6 in number, no pathologic significance; larger spots & > 6in # may indicate neurofibromatosis (90% of patient, can be a spontaneous mutation)
What are skin lesions a/w trauma?
- scratches
- forceps marks
- subQ fat necrosis
- bruising
- petechiae
- sucking blisters
- scalp lesions
How do forcep marks present?
seen on cheeks, scalp and face; red or bruised area where forceps were applied
What should be assessed for when forceps were used to facilitate a delivery?
assess for other complications such as facial palsy, fractured clavicles or skull fractures
How do subQ fat necrosis spots present?
subcutaneous nodule- hard, non pitting and sharply circumscribed; appears during 1st week of life, grows larger over several days then resolves over several weeks
What causes subQ fat necrosis?
trauma, cold or asphyxia
Why might hypercalcemia occur with subQ fat necrosis?
more likely if more than one lesion; releases calcium from damaged cells
What calcium level is preferred to be checked?
iCa: biological, active conjugated calcium- what is available for use; total Ca- total #, no helpful dx
Describe sucking blisters.
vesicles or bullae; appear on lips, fingers or hands; may be intact or ruptured; no tx req’d
What is the cause of a sucking blister?
vigorous sucking; can occur in utero
What can cause a scalp lesion?
trauma during delivery, insertion of scalp electrodes or scalp pH sampling
How does a scalp lesion present and how should it be treated?
presents as an abrasion or laceration; keep area clear & dry & observe for secondary infx
What are the 4 types of vascular skin lesions?
1) nevus simplex
2) nevus flammeus (port wine stain)
3) strawberry hemangioma
4) cavernous hemangioma
How is a nevus simplex described?
“stork bite” or “salmon patch”- most common birthmark; seen in up to 50% of all newborns; irregular bordered pink macule composed of dilated, distended capillaries- BLANCH with pressure, more prominent with crying
Where can nevus simplex be observed?
found at nape of neck, forehead, eyelids, bridge of nose or upper lip; fade by 2 years of life, if on nape of neck, may persist
Describe a nevus flammeus (port wine stain).
- flat pink or reddish purple lesion consisting of dilated, congested capillaries directly below the epidermis
- has sharply delineated edges and DOES NOT BLANCH with pressure
- does not grow in size or spontaneously resolve
Where can nevus flammeus be observed?
- may be small or cover up to 1/2 of the body
- usually unilateral but may cross midline
- most often on face, but can be anywhere
How are nevus flammeus lesions treated?
laser therapy is needed to eliminate or reduce
How does a nevus flammeus lesion present in Sturge-Weber syndrome?
port wine stain presents in the trigeminal region, may have sensory defects as well
Describe a strawberry hemangioma lesion.
- bright red, raised, lobulated tumor
- soft & compressible with sharply demarcated margins
- occur in up to 10% of newborns
- can have more than one (can be internal)
- gradually increase in size for 6 months, then regress (will turn grey and then involute)
- surrounding skin will blanch
Where can strawberry hemangioma lesions be observed?
- occur on the head, trunk or extremities
- 20-30% present at birth, remainder present by 6 months
What causes a strawberry hemangioma lesion?
dilated capillaries with endothelial proliferation in the dermal and dub dermal layers, may ulcerate
What are common complications of strawberry hemangiomas?
bleeding, ulceration, infection and compression of underlying organs
How can strawberry hemangiomas be treated?
- propanolol
- can be lasered off in beginning stages (flat and macular) and stop the evolution not the hemangioma
Describe the cavernous hemangioma.
- similar to the strawberry hemangioma
- larger, more mature vascular elements lined with endothelial cells and involves the dermis and subQ tissue
- skin is bush red in color
- soft, compressible with poorly defined borders
How should cavernous hemangiomas be treated?
increase in size during first 6-12 months, disappear spontaneously
- no tx unless interfering with vital functions
- tx with systemic corticosteroids
The presence of cavernous hemangiomas are a/w which 2 syndromes?
1) Kasabach- Merritt
2) Klippel- Trenaunay- Weber
What should be closely monitored in an infant with Kasabch- Merritt syndrome with a cavernous hemangioma?
- thrombocytopenia r/t plt sequestration
- consumption of fibrinogen and coagulation factors
What are the defining characteristics of Kippel- Trenaunay- Weber syndrome?
- increased blood flow and malformed vessels in extremities = hypertrophy of limb (bone and soft tissue)
- rare
- incidence is higher in Males
Describe neurocutaneous lesions.
tuberous sclerosis- “white leaf” macules
What is the etiology of blueberry muffin lesions?
- secondary to maternal CMV, Rubella
- extramedullary hematopoiesis (blood formed outside the medulla of the bone)
Of what concern is a neonatal lupus and thrombocytopenia rash?
benign rash, goes away in 6 months
What are the 4 stages of incontinentia pigmenti skin lesions?
1) vesicular
2) verrucous
3) hyperpigmented
4) atrophic/ hypopigmented
Describe incontinentia pigmenti skin lesions.
lesions follow Blaschko lines; F>M; males usually don’t survive
What is neurofibromatosis?
- autosomal dominant disorder
- tumors of various sizes form on peripheral nerves
- cranial nerves may also be affected
- 90% of neurofibromatosis patients will have cafe au lair spots
- neurofibromas (small skin - colored nodules) may be present at birth or may not appear until adolescence
What is Tuberous Sclerosis?
- hereditary disorder
- characterized by cutaneous and central nervous system tumors
- p/w sz, developmental delays and behavioral problems
- “ash leaf”- if more than 3 are present, further eval is req’d
- most often present on trunk and buttocks
What is Sturge- Weber syndrome?
- disorder causes a proliferation of endothelial cells, particularly in the small blood vessels
- intracerebral calcifications and atrophic changes may be present
- p/w sz, MR, hemiparesis and glaucoma
What syndromes should be suspected with the absence or atrophy of the nails?
- trisomy 13
- trisomy 18
- Turner syndrome
