Erythema Toxicum Neonatorum
- Author: Neil F Gibbs, MD; Chief Editor: William D James, MD more...
Erythema toxicum neonatorum (ETN) is a benign self-limited eruption occurring primarily in healthy newborns in the early neonatal period. Erythema toxicum neonatorum is characterized by macular erythema, papules, vesicles, and pustules, and it resolves without permanent sequelae. See the image below.
Also see the Pediatrics article, Erythema Toxicum.
Increased levels of immunological and inflammatory mediators (eg, interleukins 1 and 8, eotaxin, the adhesion molecule E-selectin, the water-channel proteins aquaphorin 1 and aquaphorin 3, the chemotactic factor psoriasin, high-mobility group box chromosomal protein 1, nitric oxide and its isoforms, the antimicrobial peptide LL-37) suggest that erythema toxicum neonatorum may be an immune system reaction.[2, 3, 4] The location of erythema toxicum neonatorum to primarily hair-bearing areas suggests that the hair follicle may be involved. Additionally, the number of mast cells is increased around hair follicles in involved skin.
The eosinophilic infiltrate of erythema toxicum neonatorum suggests an allergic- or hypersensitivity-related etiology, but no allergens have been identified. Newborn skin appears to respond to any injury with an eosinophilic infiltrate. Because erythema toxicum neonatorum is rarely seen in premature infants, it is believed that immunologically mature newborn skin is required to produce this reaction pattern.
Contactants and mechanical irritation have been considered and rejected as etiologies.
International studies have found a similar range in the incidence of erythema toxicum neonatorum, occurring in approximately one third to one half of full-term infants.
No racial or ethnic predisposition is known.
The prevalence is higher in males (55%) than in females (30%), except among females born of first pregnancies, who have a higher rate than males of first pregnancies.
See the list below:
- Erythema toxicum neonatorum presents within the first 4 days of life in full-term infants, with the peak onset occurring within the first 48 hours following birth. Rare cases have been reported at birth.[10, 11]
- Incidence rises with increasing gestational age and birth weight.
- Delayed onset rarely may occur in full-term and preterm infants up to age 14 days.[12, 13]
Prognosis of erythema toxicum neonatorum is excellent. Erythema toxicum neonatorum is a transient eruption with spontaneous resolution and no associated long-term morbidity. Erythema toxicum neonatorum may recur in approximately 11% of patients up to age 6 weeks. Recurrences tend to be mild and resolve without sequelae. Although one study found that infants with erythema toxicum neonatorum had an increased risk of atopy, subsequent studies have failed to support this finding.
Reassure parents that erythema toxicum neonatorum is not inherited or infectious, has no complications, and has an excellent prognosis with spontaneous resolution.
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].