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Features Departments Information |
 Ayelet Shani-Adir, MD Anthony J. Mancini, MD |
Dermatology quiz Ayelet Shani-Adir, MD aSpring 2002  Figure 1  Figure 2 A full-term black male presented at birth with multiple pustules distributed over the neck, trunk and thighs. The child was born after an uneventful pregnancy, via normal vaginal delivery. The dermatology service was consulted to rule out congenital infection. Physical examination revealed a well appearing neonate with scattered 1 to 3 mm pustules with no surrounding erythema over the neck, trunk, axillae (Figure 1) and inner thighs. Hyperpigmented macules with a fine collarette of scale (Figure 2) were noted in a similar distribution. The remainder of the physical examination was unremarkable. No lesions were seen on the palms, soles or oral mucosa. There was no fever, lymphadenopathy or hepatosplenomegaly. 1. The most appropriate next step in diagnosis is to: 2. The most likely diagnosis is: 3. The most appropriate therapy is: Answers: B, A, and B respectively. Diagnosis: Transient neonatal pustular melanosis Discussion: This infant presents with classic transient neonatal pustular melanosis (TNPM). This benign dermatosis was first described by Ramamurthy et al in 1976[1]. It occurs at birth in up to 5% of black infants and less than 0.3% of white infants[2]. It is more common in term infants and males and females are affected equally. The etiology of TNPM is unknown but there is no correlation with maternal or fetal infection. Clinically, the eruption consists of superficial pustules which are usually present at birth without surrounding erythema. Lesions measure 1 to 5 mm and may be found in clusters or singly. The pustules tend to rupture easily, with the formation of pigmented macules that have a characteristic collarette of scale. The pigmented macules usually fade within 3 to 4 weeks, but may persist for several months[3]. Most commonly affected areas include the chin, neck, upper chest, lower back, buttocks, abdomen and thighs. Palms and soles may be involved, and there is no mucosal involvement. Clusters of pustules tend to occur on pressure areas. No systemic symptoms are associated with the lesions[4]. Smears of vesicle fluid stained with Wright’s or Giemsa stain demonstrate polymorphic neutrophils and occasional eosinophils. Gram’s stain shows neutrophils but no bacteria, and fungal elements are absent. Skin biopsy is rarely necessary for diagnosis, but if performed, reveals hyperkeratosis, acanthosis and an intracorneal or subepidermal pustule filled with neutrophils, a few eosinophils and keratinous debris. The differential diagnosis of TNPM includes erythema toxicum neonatorum, staphylococcal impetigo and other bacterial infections, congenital candidiasis, neonatal herpes virus or varicella infection, acropustulosis of infancy, eosinophilic pustular folliculitis and miliaria. The diagnosis of TNPM is based on the time of onset, lesional morphology, demonstration of neutrophils on Wright’s stain (in contrast with the predominance of eosinophils in erythema toxicum neonatorum), and lack of organisms on Gram’s stain and potassium hydroxide preparations. In addition, the well status of the infant may help differentiate TNPM from congenital or neonatal infections. A clear-cut differentiation between TNPM and erythema toxicum neonatorum is not always possible, and some authors believe they are two different clinical expressions of the same entity[5]. No specific therapy is recommended for TNPM, since it resolves spontaneously. Parents should be informed, however, that the hyperpigmented macules may persist for up to 3 to 6 months. REFERENCES 1. Ramamurthy RS, Reveri M. Esterly NB, et al. Transient neonatal pustular melanosis. J Pediatr 1976;88:831–5. 2. Wyre HW, Murphy MO. Transient neonatal pustular melanosis. Arch Dermatol 1979;115:458. 3. Van Praag MCG, Van Rooij RWG, Folkers E, et al. Diagnosis and treatment of pustular disorders in the neonate. Pediatr Dermatol 1997;14:131–43. 4. Gupta AK, Rasmussen JE. What’s new in pediatric dermatology. J Am Acad Dermatol 1988;18:239–59. 5. Coroleu LW. Natal PA, Fernandez FC, et al. Transient neonatal pustular melanosis. Ann Espanol Pediatr 1990;33:117. |