title: DNA of Dientamoeba fragilis detected within surface-sterilized eggs of Enterobius vermicularis.
abstract: With no evidence of a cyst stage, the mode of transmission of Dientamoeba fragilis, an intestinal protozoon of common occurrence and suggested pathogenicity, is incompletely known. Numerous studies have suggested that eggs of intestinal nematodes, primarily Enterobius vermicularis (pinworm), can serve as vectors for D. fragilis, although attempts to culture D. fragilis from pinworm eggs have been unsuccessful and data from epidemiological studies on D. fragilis/pinworm co-infection have been conflicting. The aim of this study was to investigate whether we could detect D. fragilis DNA from pinworm eggs collected from routine diagnostic samples (cellophane tape) and surface-sterilised by hypochlorite. DNA was extracted from individual eggs and tested by PCR using D. fragilis- and E. vermicularis-specific primers; amplicons were sequenced for confirmation. In cellophane tape samples from 64 patients with unknown D. fragilis status we detected D. fragilis DNA in 12/238 (5%) eggs, and in a patient known to harbour D. fragilis we detected D. fragilis DNA in 39/99 (39%) eggs. The finding of D. fragilis DNA within eggs of E. vermicularis strongly supports the hypothesis of D. fragilis-transmission by pinworm and has implications for antimicrobial intervention as well as control and public health measures.
authors.affiliation: Laboratory of Parasitology, Department of Microbiology and Infection Control, Statens Serum Institut, Artillerivej 5, DK-2300 Copenhagen S, Denmark. dsr@ssi.dk
authors.forename: Dennis
authors.initials: D
authors.lastname: Röser
authors.forename: Peter
authors.initials: P
authors.lastname: Nejsum
authors.forename: Anne Josefine
authors.initials: AJ
authors.lastname: Carlsgart
authors.forename: Henrik Vedel
authors.initials: HV
authors.lastname: Nielsen
authors.forename: Christen Rune
authors.initials: CR
authors.lastname: Stensvold
mesh_terms: D000818:Animals; D016054:DNA, Protozoan / Q000187:drug effects / Q000302:isolation & purification*; D004029:Dientamoeba / Q000235:genetics / Q000302:isolation & purification*; D004030:Dientamoebiasis / Q000635:transmission*; D004199:Disease Vectors; D017229:Enterobiasis / Q000469:parasitology; D004757:Enterobius / Q000469:parasitology*; D005260:Female; D006801:Humans; D006997:Hypochlorous Acid / Q000494:pharmacology; D010063:Ovum / Q000469:parasitology; D016877:Oxidants / Q000494:pharmacology
chemical_list: D016054:DNA, Protozoan; D016877:Oxidants; D006997:Hypochlorous Acid