Erythema Toxicum Neonatorum Clinical Presentation
- Author: Neil F Gibbs, MD; Chief Editor: William D James, MD more...
When evaluating for erythema toxicum neonatorum (ETN), focus the history on age at onset of the eruption, absence of systemic signs (eg, fever, irritability, lethargy, mucocutaneous involvement), or maternal history of herpes simplex/varicella viral infection, bacterial pyoderma, or candidiasis.
Infants with erythema toxicum neonatorum are otherwise healthy and lack systemic symptoms. The eruption is self-limited with most cases resolving within 5-14 days without residual sequelae. Recurrences are uncommon but have been reported up to the sixth week of life. They tend to be mild in severity.
Focus the physical examination on location, size, and distribution of macules, wheals, papules, and pustules on the skin. Note the absence of mucosal, palmar, or plantar involvement (ie, non – hair-bearing skin). Signs of systemic toxicity, including hypothermia or hyperthermia, lethargy, and irritability, are not associated with erythema toxicum neonatorum.
Erythema toxicum neonatorum most commonly presents with a blotchy, evanescent, macular erythema, often on the face or trunk.
The macules are irregular, blanchable, and vary in size.
In more severe cases, pale yellow or white wheals or papules on an erythematous base may follow. In approximately 10% of patients, 2-4 mm pustules develop.
Numbers and distribution of lesions vary from a few and widely scattered to numerous and extensive.
Sites of predilection include the most commonly include the trunk, buttocks, and proximal limbs, but lesions may occur anywhere, including the genitalia. Involvement of the mucous membranes and palms and soles rarely occurs.
See the images below.
The cause of erythema toxicum neonatorum is unknown. Multiple theories have been proposed to explain this common disorder.
Neonates have an increased number of hair follicles compared with adults, and the occurrence of erythema toxicum neonatorum in non–hair-bearing areas such as palms and soles is rare. Inflammatory cells tend to concentrate around hair follicles, and coccilike microbes have been demonstrated in the follicular epithelium and inside the inflammatory cells. This suggests that erythema toxicum neonatorum may be a response to microbes that have penetrated the hair follicle. This process may possibly be integral in developing the new immune system.
The high frequency of eosinophilia suggests an allergic basis, leading some authors to suggest that erythema toxicum neonatorum may be an immediate hypersensitivity reaction to a substance passed from the mother transplacentally; however, convincing support is lacking for this theory.
No responsible exotoxin, allergen, component of sebum, or infectious agent has been linked credibly to erythema toxicum neonatorum.
Medications administered to newborns and the mode of feeding have no effect on incidence.
Other proposed theories include a transient adjustment reaction of the skin to mechanical or thermal stimulation or an acute graft-versus-host reaction induced by the maternal-fetal transfer of lymphocytes before or during delivery. Analysis of skin samples of 2 male patients with erythema toxicum neonatorum did not support a graft-versus-host reaction because no maternal cells were found in the samples using fluorescence in situ hybridization identification of cells with 2 XX chromosomes.
Risk factors include higher birth weight, greater gestational age, and vaginal delivery. A positive correlation has been recognized between the length of labor and both the incidence of erythema toxicum neonatorum and the duration of the cutaneous manifestations.[9, 21]
Schwartz RA, Janniger CK. Erythema toxicum neonatorum. Cutis. 1996 Aug. 58(2):153-5. [Medline].
Marchini G, Hultenby K, Nelson A, et al. Increased expression of HMGB-1 in the skin lesions of erythema toxicum. Pediatr Dermatol. 2007 Sep-Oct. 24(5):474-82. [Medline].
Marchini G, Lindow S, Brismar H, et al. The newborn infant is protected by an innate antimicrobial barrier: peptide antibiotics are present in the skin and vernix caseosa. Br J Dermatol. 2002 Dec. 147(6):1127-34. [Medline].
Marchini G, Stabi B, Kankes K, Lonne-Rahm S, Ostergaard M, Nielsen S. AQP1 and AQP3, psoriasin, and nitric oxide synthases 1-3 are inflammatory mediators in erythema toxicum neonatorum. Pediatr Dermatol. 2003 Sep-Oct. 20(5):377-84. [Medline].
Nelson A, Ulfgren AK, Edner J, Stabi B, Brismar H, Hultenby K. Urticaria Neonatorum: accumulation of tryptase-expressing mast cells in the skin lesions of newborns with Erythema Toxicum. Pediatr Allergy Immunol. 2007 Dec. 18(8):652-8. [Medline].
Carr JA, Hodgman JE, Freedman RI, Levan NE. Relationship between toxic erythema and infant maturity. Am J Dis Child. 1966 Aug. 112(2):129-34. [Medline].
Kanada KN, Merin MR, Munden A, Friedlander SF. A prospective study of cutaneous findings in newborns in the United States: correlation with race, ethnicity, and gestational status using updated classification and nomenclature. J Pediatr. 2012 Aug. 161(2):240-5. [Medline].
Jacobs AH, Walton RG. The incidence of birthmarks in the neonate. Pediatrics. 1976 Aug. 58(2):218-22. [Medline].
Liu C, Feng J, Qu R, et al. Epidemiologic study of the predisposing factors in erythema toxicum neonatorum. Dermatology. 2005. 210(4):269-72. [Medline].
Levy HL, Cothran F. Erythema toxicum neonatorum present at birth. Am J Dis Child. 1962 Apr. 103:617-9. [Medline].
Marino LJ. Toxic erythema present at birth. Arch Dermatol. 1965 Oct. 92(4):402-3. [Medline].
Akoglu G, Ersoy Evans S, Akca T, Sahin S. An unusual presentation of erythema toxicum neonatorum: delayed onset in a preterm infant. Pediatr Dermatol. 2006 May-Jun. 23(3):301-2. [Medline].
Chang MW, Jiang SB, Orlow SJ. Atypical erythema toxicum neonatorum of delayed onset in a term infant. Pediatr Dermatol. 1999 Mar-Apr. 16(2):137-41. [Medline].
Singh M, Arora NK, Sroa HS. Urticaria neonatorum--an earliest marker of atopy. Indian J Med Res. 1980 Feb. 71:273-7. [Medline].
Monteagudo B, Labandeira J, Cabanillas M, Acevedo A, Toribio J. Prospective Study of Erythema Toxicum Neonatorum: Epidemiology and Predisposing Factors. Pediatr Dermatol. 2011 Nov 8. [Medline].
Maffei FA, Michaels MG, Wald ER. An unusual presentation of erythema toxicum scrotal pustules present at birth. Arch Pediatr Adolesc Med. 1996 Jun. 150(6):649-50. [Medline].
Marchini G, Nelson A, Edner J, Lonne-Rahm S, Stavreus-Evers A, Hultenby K. Erythema toxicum neonatorum is an innate immune response to commensal microbes penetrated into the skin of the newborn infant. Pediatr Res. 2005 Sep. 58(3):613-6. [Medline].
Keitel HG, Yadav V. Etiology of toxic erythema. Erythema toxicum neonatorum. Am J Dis Child. 1963 Sep. 106:306-9. [Medline].
Bassukas ID. Is erythema toxicum neonatorum a mild self-limited acute cutaneous graft-versus-host-reaction from maternal-to-fetal lymphocyte transfer?. Med Hypotheses. 1992 Aug. 38(4):334-8. [Medline].
Droitcourt C, Khosrotehran K, Halaby E, Aractingi S. Maternal cells are not responsible [corrected] for erythema toxicum neonatorum [corrected]. Pediatr Dermatol. 2008 May-Jun. 25(3):411-3. [Medline].
Monteagudo B, Labandeira J, Cabanillas M, Acevedo A, Toribio J. Prospective study of erythema toxicum neonatorum: epidemiology and predisposing factors. Pediatr Dermatol. 2012 Mar-Apr. 29(2):166-8. [Medline].
Ferrandiz C, Coroleu W, Ribera M, Lorenzo JC, Natal A. Sterile transient neonatal pustulosis is a precocious form of erythema toxicum neonatorum. Dermatology. 1992. 185(1):18-22. [Medline].
Van Praag MC, Van Rooij RW, Folkers E, Spritzer R, Menke HE, Oranje AP. Diagnosis and treatment of pustular disorders in the neonate. Pediatr Dermatol. 1997 Mar-Apr. 14(2):131-43. [Medline].
Freeman RG, Spiller R, Knox JM. Histopathology of erythema toxicum neonatorum. Arch Dermatol. 1960 Oct. 82:586-9. [Medline].
Luders D. Histologic observations in erythema toxicum neonatorum. Pediatrics. 1960 Aug. 26:219-24. [Medline].
Marchini G, Ulfgren AK, Lore K, Stabi B, Berggren V, Lonne-Rahm S. Erythema toxicum neonatorum: an immunohistochemical analysis. Pediatr Dermatol. 2001 May-Jun. 18(3):177-87. [Medline].