Neonatal acne, also known as acne neonatorum, is an

acneiform eruption Acneiform eruptions are a group of dermatoses including acne vulgaris, rosacea, folliculitis, and perioral dermatitis. Restated, acneiform eruptions are follicular eruptions characterized by papules and pustules resembling acne.James, William; Be ...

that occurs in newborns or infants within the first 4-6 weeks of life, and presents with open and closed comedones on the cheeks, chin and forehead. The main cause is not known for certain but it may be caused by maternal androgens transferred from the mother to the newborn from the placenta and androgens produced by the fetal adrenal gland and neonatal testicles that stimulate sebaceous glands to increase production of sebum. As a self-limiting condition, neonatal acne tends to resolve on its own but treatment options can include topical benzoyl peroxide, topical retinoids, topical antibiotics and topical antifungals.

Signs and Symptoms

Neonatal acne presents from birth to within the first 4-6 weeks of life. Common symptoms are open and closed comedones such as

papules A papule is a small, well-defined bump in the skin. It may have a rounded, pointed or flat top, and may have a dip. It can appear with a stalk, be thread-like or look warty. It can be soft or firm and its surface may be rough or smooth. Some h ...

and

pustules A skin condition, also known as cutaneous condition, is any medical condition that affects the integumentary system—the organ system that encloses the body and includes skin, nails, and related muscle and glands. The major function of this ...

that occur most commonly on the face on the areas of the cheeks, chin and forehead. Less commonly, lesions can be present on the chest and back.

Causes

It is believed that maternal

androgens An androgen (from Greek ''andr-'', the stem of the word meaning "man") is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This in ...

passed to the infant through the placenta has a role in stimulating

sebaceous glands A sebaceous gland is a microscopic exocrine gland in the skin that opens into a hair follicle to secrete an oily or waxy matter, called sebum, which lubricates the hair and skin of mammals. In humans, sebaceous glands occur in the greatest num ...

leading to increased sebum production that causes comedone formation.

Dehydroepiandrosterone Dehydroepiandrosterone (DHEA), also known as androstenolone, is an endogenous steroid hormone precursor. It is one of the most abundant circulating steroids in humans. DHEA is produced in the adrenal glands, the gonads, and the brain. It fun ...

(DHEA) produced from the fetal adrenal gland and androgen production from neonatal testicles may also stimulate sebum production from sebaceous glands. The role of genetics is unclear but a positive family history supports association with neonatal acne. Some researchers suggest the role of ''

Malassezia ''Malassezia'' (formerly known as ''Pityrosporum'') is a genus of fungi. It is the sole genus in family Malasseziaceae, which is the only family in order Malasseziales, itself the single member of class Malasseziomycetes. ''Malassezia'' species a ...

'' colonization causing hypersensitivity reactions in skin but this tends to be linked to neonatal cephalic pustulosis more so than neonatal acne.

Diagnosis

A work up is suggested in cases of severe acneiform eruptions or with signs of growth abnormalities to rule out potential endocrine diseases, tumor formation, or gonadal development abnormalities. A referral to a pediatric endocrinologist may be warranted.

Differential Diagnosis

Other causes of acneiform eruptions such as those induced by the use of topical products like creams, ointments and shampoos on the skin are often ruled out before diagnosis. Maternal medications like

lithium Lithium (from el, λίθος, lithos, lit=stone) is a chemical element with the symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the least dense metal and the least dense solid ...

and high dose corticosteroids may also induce formulation of pustules in newborns and can be assessed with a thorough family history. Likewise, newborns can be assessed for infection whether bacterial, fungal or viral in nature.

Erythema toxicum neonatorum Erythema toxicum neonatorum is a common, non-threatening rash in newborns. It appears in 4-70% of newborns within the first week of life, and it typically improves within 1–2 weeks. It only occurs during the newborn period, but may appear slightl ...

, neonatal cephalic pustulosis, transient neonatal pustular melanosis,

folliculitis Folliculitis is the infection and inflammation of one or more hair follicles. The condition may occur anywhere on hair-covered skin. The rash may appear as pimples that come to white tips on the face, chest, back, arms, legs, buttocks, or head. ...

miliaria Miliaria, also called heat rash, sweat rash, or prickly heat, is a skin disease marked by small, itchy rashes due to sweat trapped under the skin by clogged sweat-gland ducts. Miliaria is a common ailment in hot and humid conditions, such as in ...

and milia are often ruled out before diagnosis. Some experts consider neonatal cephalic pustulosis (NCP) a form of neonatal acne while others do not. NCP presents with facial papules and pustules but no comedones. NCP has been linked to ''Malassezia'' colonization, a normal yeast found on skin, but inconsistent patterns of positive colonization and NCP suggests that ''Malassezia'' hypersensitivity reactions in susceptible newborns are the cause of the acneiform eruptions rather than colonization itself.

Treatment

Neonatal acne will typically resolve by itself in 2-6 months. In mild cases, cleansing the face daily with gentle soap and water while avoiding use of potential comedogenic soaps, lotions and oils is often enough. Further treatment is not necessary but in severe or persistent cases topical therapy can be initiated.

Benzoyl Peroxide

Topical benzoyl peroxide (BPO) may be indicated in persistent or inflammatory cases. BPO is a lipophilic agent that penetrates into sebaceous glands and generates reactive oxygen species that kill '' P. acnes.'' It also has comedolytic and anti-inflammatory properties and can prevent development of

antimicrobial resistance Antimicrobial resistance (AMR) occurs when microbes evolve mechanisms that protect them from the effects of antimicrobials. All classes of microbes can evolve resistance. Fungi evolve antifungal resistance. Viruses evolve antiviral resistance. P ...

Topical Retinoids

Topical retinoids can be used alone or in combination with BPO. Retinoids are derived from vitamin A. They bind to retinoic receptors to normalize the rate of keratinocyte growth and prevent inflammation. Overactive

keratinocyte Keratinocytes are the primary type of cell found in the epidermis, the outermost layer of the skin. In humans, they constitute 90% of epidermal skin cells. Basal cells in the basal layer (''stratum basale'') of the skin are sometimes referre ...

production can lead to comedone formation.

Topical Antibiotics

In cases where scarring is a concern, topical antibiotics may be recommended. Topical clindamycin and erythromycin are the most commonly prescribed options for acne. Antibiotics kill ''P. acnes'' on skin that could be causing inflammation. With the emergence of resistant ''P. acnes'', experts recommend topical antibiotics to be used in combination with BPO to reduce the risk of development of antimicrobial resistance. The most common side effects of topical antibiotics are stinging, burning and redness at the site of application.

Topical antifungals

Some experts suggest the use of topical ketoconazole in newborns with more pustular neonatal acne as there is evidence it shortens duration of lesions. This may be in cases more suggestive of neonatal cephalic pustulosis than neonatal acne.

Epidemiology

20% of newborns will develop neonatal acne however there has been debate if this is an accurate representation of actual diagnosed cases of acne as this could include other acneiform eruptions that do not present with comedones like neonatal cephalic pustulosis. Neonatal acne occurs more often in boys than in girls.