title: Natural-biomembrane dressing and hypersensitivity.
abstract: BACKGROUND
  The natural biomembrane of latex extracted from Hevea brasiliensis has been used as a dressing for skin ulcers.
  
  
  OBJECTIVE
  To evaluate how safe the natural biomembrane is in relation to hypersensitivity to latex when used as a dressing.
  
  
  METHODS
  We selected patients with skin ulcers, forming the following groups: control - low occupational exposure to latex (n = 17); latex-exposed control - high occupational exposure (n = 14); ulcerated, using the natural biomembrane (n = 13); ulcerated control, not using the natural biomembrane (n = 14); and new cases (n = 9), assessed before and after 3 months of using the natural biomembrane. All patients underwent clinical and epidemiological evaluation for latex hypersensitivity and specific IgE (UniCap(®)), and the control and latex-exposed control groups underwent the patch test.
  
  
  RESULTS
  Hypersensitivity was positive in 64.7% of the patients in the control group, 71.4% of the patients in the latex-exposed control group, 61.5% of the ulcerated using the natural biomembrane, 35.7% of the ulcerated control, and only 22 , 2% of the new cases. In the patch test of the control and latex-exposed control groups, only one individual in the control group (low contact) showed erythema in the first reading, which became negative in the second. The mean contact with latex in the latex-exposed control group was 3.42 hours / day. In the fluoroimmunoenzymatic assay, most of the sera was classified as zero (range 0-6). No serum was rated above 2, which is not considered significant for hypersensitivity (classification > 4).
  
  
  CONCLUSIONS
  The natural biomembrane proved to be safe as a dressing, for it did not induce hypersensitivity reactions among the volunteers who underwent the patch test or among users of the natural biomembrane, as it was clinically and immunologically demonstrated by IgE levels.
authors.affiliation: Divisão de Dermatologia, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Brazil. mandrey@fmrp.usp.br
authors.forename: Marco Andrey Cipriani
authors.initials: MA
authors.lastname: Frade
authors.forename: Joaquim
authors.initials: J
authors.lastname: Coutinho Netto
authors.forename: Fernanda Guzzo
authors.initials: FG
authors.lastname: Gomes
authors.forename: Eduardo Lopez
authors.initials: EL
authors.lastname: Mazzucato
authors.forename: Thiago Antônio Moretti de
authors.initials: TA
authors.lastname: Andrade
authors.forename: Norma Tiraboschi
authors.initials: NT
authors.lastname: Foss
mesh_terms: D000328:Adult; D001458:Bandages / Q000009:adverse effects*; D001672:Biocompatible Materials / Q000009:adverse effects / Q000627:therapeutic use*; D016022:Case-Control Studies; D003429:Cross Reactions; D005260:Female; D028482:Hevea; D006801:Humans; D007840:Latex / Q000276:immunology; D020315:Latex Hypersensitivity / Q000175:diagnosis*; D007871:Leg Ulcer / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010328:Patch Tests; D055815:Young Adult
chemical_list: D001672:Biocompatible Materials; D007840:Latex