Pseudo-lysosomal storage disease caused by EMLA cream.
Prilocaine-lidocaine emulsion (EMLA cream) is a topical anaesthetic commonly used prior to diagnostic and therapeutic procedures. While undergoing clinical investigation for the suspicion of a metabolic disorder, a series of children underwent skin biopsy with EMLA cream pretreatment. In each case, the pathologist identified ultrastructural features consistent with a lysosomal storage disorder, yet the clinical features were not consistent with the pathological findings. Ultrastructural artefact was suspected, resulting from the use of the EMLA cream. All patients underwent repeat skin biopsy without EMLA cream. Biopsies were reviewed by two pathologists blinded to the previous biopsy findings. Electron microscopy repeated without the use of EMLA cream was normal. It is concluded that the use of EMLA cream causes ultrastructural artefact and should be avoided prior to skin biopsy for electron microscopy.
Department of Pathology, Children's and Women's Health Centre of British Columbia, 4500 Oak Street, Room 2F22, Vancouver, British Columbia V6H 3N1, Canada. hvallance@cw.bc.ca
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Vallance
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Chaba
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Clarke
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Taylor
D000779:Anesthetics, Local / Q000009:adverse effects*; D001706:Biopsy; D002675:Child, Preschool; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D007223:Infant; D008012:Lidocaine / Q000009:adverse effects*; D000077442:Lidocaine, Prilocaine Drug Combination; D016464:Lysosomal Storage Diseases / Q000139:chemically induced* / Q000473:pathology; D008297:Male; D008854:Microscopy, Electron; D009824:Ointments; D011318:Prilocaine / Q000009:adverse effects*; D012867:Skin / Q000648:ultrastructure
D000779:Anesthetics, Local; D000077442:Lidocaine, Prilocaine Drug Combination; D009824:Ointments; D011318:Prilocaine; D008012:Lidocaine