LAKE TAHOE, CALIF. – Evaluation of an infant with a vesiculopustular lesion entails a pragmatic approach, with three assessment steps, according to pediatric dermatologist Lawrence A. Schachner, MD.
Dr. Lawrence A. Schachner
At the annual meeting of the Society for Pediatric Dermatology, Dr. Schachner noted that the differential diagnosis of noninfectious, usually benign neonatal vesiculopustular lesions includes acropustulosis of infancy; eosinophilic pustular folliculitis; erythema toxicum neonatorum; miliaria crystallina, rubra, or profunda; transient neonatal pustular melanosis; and neonatal sucking blisters. Noninfectious lesions that can be potentially serious include acrodermatitis enteropathica, bullous pemphigoid, epidermolysis bullosa, epidermolytic hyperkeratosis, incontinentia pigmenti, Langerhans cell histiocytosis, pemphigus vulgaris, pustular psoriasis, and urticarial pigmentosa.
Step 1 for evaluating vesiculopustular lesions involves drawing out the fluid for bacterial cultures and sensitivity, Gram stains, viral culture and/or serology, said Dr. Schachner, who directs the division of pediatric dermatology at the University of Miami.
Step 2 involves snipping off the lesion’s roof for a potassium hydroxide test to send for dermatopathology or frozen pathology.
Step 3 involves scraping the lesion’s base for viral cytology and cell identification. “If we can see a predominant cell type, that’s where the action is,” said Dr. Schachner, professor of pediatrics at the university. If cytology reveals polymorphic neutrophils, differential diagnoses include transient neonatal pustular melanosis, infantile acropustulosis, bullous impetigo, and pustular psoriasis. If cytology reveals eosinophils, differential diagnoses include eosinophilic pustular folliculitis of infancy, erythema toxicum neonatorum, incontinentia pigmenti, bullous pemphigoid, drug reactions, and arthropod bites. The presence of lymphocytes on cytology, meanwhile, may suggest a differential diagnosis miliaria or acrodermatitis enteropathica.
“When in doubt about the diagnosis, biopsy,” Dr. Schachner said. “This, to me, is a pragmatic approach.”
Dr. Schachner disclosed that he is an investigator for Astellas, Ferndale Labs, Novartis, Organogenesis, Stiefel Laboratories, Berg Pharma, Medimetrics, and Lilly. He is a consultant to Beiersdorf, Lexington, TopMD, Cutanea, Hoth Therapeutics, and Mustela.