Common pediatric rashes JFK pediatric core curriculum MGH Center for Global Health Pediatric Global Health Leadership Fellowship Credits: Brett Nelson, MD, MPH Sohil Patel, MD

Discussion outline Dermatology terminology Common benign newborn rashes Common infectious newborn rashes Newborn vascular lesions Various other pediatric rashes

Common dermatology terms Macule: circumscribed change in skin color without elevation or depression Papule: solid elevated lesion usually <0.5 cm in diameter Plaque: raised lesion >0.5cm in diameter Wheal (hive): rounded or flat-topped elevated lesion formed by local dermal edema Purpura: non-blanching erythema or violaceous color due to extravasation of blood Nodule: palpable solid lesion of varying size Vesicle: circumscribed elevated lesion which contains free fluid and is <0.5 cm in diameter Bulla (blister): same as vesicle but with diameter >0.5 cm Cyst: sac containing liquid or semisolid material usually in the dermis Pustule: circumscribed elevated lesion which contains pus Abscess: collection of pus in the dermis or subcutis

Benign newborn rashes Erythema toxicum neonatorum Miliaria Neonatal acne Milia Seborrheic dermatitis Benign pustular melanosis of the newborn Sucking blisters Presented in random order…. Some other ones not covered are: -- mongolian spots -- nappy rash (diaper dermatitis)

Miliaria Due to obstruction and rupture of exocrine sweat duct Commonly seen secondary to thermal stress, particularly with crops of lesions over face, scalp, and trunk Important to ensure infant is not over-wrapped Once heat stress is removed, lesions usually resolve quickly

Neonatal acne Can be present at birth or develop in first 2-4 weeks of life Consists of pustules over the cheeks primarily, but also involves other areas of face and scalp No comedones in neonatal form Resolves spontaneously and without scarring There is controversy over whether it is truly acne or whether it represents a form of pustular disorder in the newborn period.  As a result, the term neonatal cephalic pustulosis has been mooted. As opposed to infantile acne (which develops after 2 months) and acne of adolescence, there are no comedomes in the neonatal form. It may be difficult to differentiate between acne and miliaria rubra.

Benign pustular melanosis of the newborn Lesions present at birth Superficial pustules which rupture easily without pus content, leaving spot of hyperpigmentation Pustules last 1-2 days but pigmented spots may persist for a while Any area of the body may be involved Smears from pustules reveal polymorphonuclear leukocytes with absence of organisms Etiology is unknown.

Seborrheic dermatitis Primarily affects scalp and intertriginous areas Involvement of scalp is frequently termed "cradle cap“ and manifests as greasy, yellow plaques on scalp Most common in first 6 weeks of life, but can occur in children up to 12 months of age Usually clears up without treatment in 3-4 weeks If needed, treatment can include mild tar shampoo, oatmeal baths, avoidance of soaps, and occasional use of mild topical steroid Involvement of skin creases can lead to secondary candidal infections Etiology unknown Other commonly affected areas include the forehead and eyebrows (as in the photo to the left), nasolabial folds, and external ears.

Erythema toxicum neonatorum Onset on day 2-3 of life, mostly in term babies Lesions wax and wane over ensuing 3-6 days Lesions may intensify or coalesce particularly in response to local heat Central white-yellow papule surrounded by a halo of erythema, mainly over trunk (but also on limbs and face) Scrapings of lesions would reveal eosinophils Etiology unknown

Milia Tiny, white, usually discrete papules Inclusion cysts that contain trapped keratinised stratum corneum Commonly occur on face and scalp Usually resolve within a few months without treatment Rarely associated with dermatologic syndromes Epidermolysis bullosa, oro-facial-digital syndrome (type 1) Similar lesions may occasionally be seen in mouth When on hard palate, called Epstein's pearls When on alveolar ridges, called alveolar cysts or Bohn's nodules

Sucking blisters Present at birth, most often over dorsal and lateral aspect of wrist Either bilateral or unilateral May appear like well-demarcated bruises or vesicles Infant is noted to exhibit excessive sucking activity In the lower image, the blister present on the dorsal surface of the second finger burst open discharging yellow serous fluid. Such a lesion may be confused with bullous impetigo but the time of onset, the location and the examination should differentiate the two.

Infectious newborn lesions Staphylococcal pustules Herpes simplex Generalized in utero infection Paronychia Bullous impetigo Omphalitis Congenital syphilis Candida Dermatitis Presented in random order….

Paronychia Localized inflammation with infection of nail fold Relatively common in infants Treat most infections with oral antibiotics and severe cases with IV antibiotics First line treatment is usually flucloxacillin/floxacillin for Staphylococcus aureus or Streptococcus pyogenes For chronic lesions, consider Gram-negative organisms or Candida as potential causes This SEPARATION may be exacerbated by the baby sucking their fingers or by overzealous trimming of the infant's finger nails.

Bullous impetigo Skin infection typically caused by Staphylococcus aureus Lesions tend to appear DOL 5-10 Any body site may be involved, with predilection to diaper area Bullae are flaccid, containing straw colored or turbid fluid Rupture easily leaving moist denuded area (“honey-crusted lesions”) Treatment with systemic antibiotics, particularly for lesions around umbilicus

Staphylococcal pustule Typically seen first few days of life Predilection to neck, axilla, and inguinal areas Nearly always caused by Staphylococcus aureus If one lesion, may be treated "expectantly" with application of chlorhexidine (mainly to prevent spread) However, if more than one lesion, oral antibiotics are indicated after culture is taken For pustules in periumbilical area, consider systemic antibiotics

Herpes simplex May involve skin, mouth, or eye Lesions typically develop DOL 5-10 Grouped vesicles may be seen, often in linear distribution if affecting limbs (1st slide) If vesicle eroded, shallow ulcer with erythematous base may be seen (2nd slide) May have associated lesions on lips -- similar to those of "cold sore" in an adult … and when they do, they provide valuable clues to the possibility of associated disseminated or CNS herpes However, there are exceptions to the rule and occasionally lesions may be present at birth and presumably such infants would have been exposed to the virus several days prior to delivery.

Herpes Simplex: SEM HSV infection develops in one of three patterns, with roughly equal frequency Localized to the skin, eyes, and mouth (SEM) Localized CNS disease Disseminated disease involving multiple organs Can develop anytime between birth and four weeks Patients with disseminated disease present earliest, often within the first week after delivery, although CNS symptoms usually occur during the second or third week

Discussion point: How do you differentiate HSV from impetigo from staph from millia?

Omphalitis Infection of umbilical stump Erythematous, edematous, +/- exudative Most commonly occurs after day 3 Infective organisms are variable, but S.aureus, S.pyogenes, and Gram-negative organisms are common If cultures available, swab affected area for Gram-stain and culture to guide treatment Initiate IV antibiotics There may be signs of cellulitis ("cord flare") and, very rarely, fasciitis. It is important to differentiate omphalitis (or funisitis - infection of the cord itself) from other causes of serous or exudative umbilical discharges, such as a persistent vitelline duct, umbilical papilloma, or urachal remnant.

Congenital syphilis Dermatological findings quite variable Classically involve palmar/plantar, perioral, and anogenital regions Early lesions include petechiae, hemorrhagic vesicles, and bullae Lesions extremely infectious May have extracutaneous findings Hepatomegaly, low birth weight, thrombocytopenia, anaemia, jaundice, respiratory distress, osteochondritis, hydrops fetalis, meningitis, chorioretinitis, and pseudoparalysis Older infants may present with "snuffles" (syphylitic rhinitis) which, in early stages, may be mistaken for URI Because of the variable lesions and clinical symptoms seen with CS, it has frequently been termed "the great imitator", and it is important to consider alternative diagnoses or vesiculobullous diseases that involve the palms and soles.

Candida Dermatitis A common condition of young infants Most commonly caused by C. albicans Characteristically appears as an erythematous rash in the inguinal region Classically has areas of confluent erythema with discrete erythematous papules and plaques with superficial scales Satellite lesions are typically noted

Candida Dermatitis

Newborn vascular lesions Harlequin phenomenon Cutis marmorata

Cutis marmorata Reticulated pattern of constricted capillaries and venules Often called "mottling“ Due to vasomotor instability in immature infants Generally resolves with increasing age and for most infants is of no significance However, may reflect underlying poor perfusion Infants who develop mottling and are unwell need to be clinically evaluated for sepsis and other illnesses

Harlequin phenomenon Striking reddening of one side of body and blanching of other half Each episode may last from seconds to minutes Episodes occur most often during first few days of life Thought to be vascular manifestation of changes occurring in newborn’s autonomic system

Various other pediatric rashes Adapted from: Paul Geltman, MD, MPH and Johns Hopkins DermAtlas The following are ~80 slides to be used as time permits – possibly during a second lecture session. Some photos may contain nude anatomy and would not be appropriate for openly public display.

Measles Description: red confluent papular eruption Comments: A 5 year old boy developed fever, headache, and sore throat followed several days later by a red papular rash on the face. Five days later the rash was confluent on his face and disseminated over the trunk and extremities including the palms and soles.

[The remainder of these ~80 slides have been temporarily removed from this lecture due to space limitations. The full lecture (25MB) is available from brett.d.nelson@gmail.com.]