title: Mini-FLOTAC, Kato-Katz and McMaster: three methods, one goal; highlights from north Argentina.
abstract: BACKGROUND
  Copro-parasitological diagnosis is still a challenge in management of helminth infections at individual and community levels in resource-limited settings.The aim of our study was to compare the performance of three quantitative techniques: Kato-Katz, McMaster and Mini-FLOTAC methids. The study was carried out in Oran, Northern Argentina.
  
  
  METHODS
  200 schoolchildren were enrolled to provide a single stool sample, which was tested for helminth infections with Kato-Katz, McMaster and Mini-FLOTAC methods. The Mini-FLOTAC was performed with two flotation solutions (FS2 saturated saline and FS7 zinc sulphate). Preparation and reading time for each of the three methods was calculated both when processing single and multiple samples.
  
  
  RESULTS
  Out of 193 schoolchildren examined, 40% were positive for any helminth infection by any method; the most prevalent was Hymenolepis nana (23%) followed by Ascaris lumbricoides (17%) and a third group of less prevalent helminths: Enterobius vermicularis, Trichuris trichiura and hookworms (11% all together). Mini-FLOTAC FS2 was more sensitive than FS7 for H. nana (93% vs 78%) and for other helminths (85% vs 80%), whereas FS7 was more sensitive for A. lumbricoides (87% vs 61%). Kato-Katz method was more sensitive than McMaster method for A. lumbricoides (84% vs 48%) and for other helminths (48% vs 43%) except for H. nana (49% vs 61%). As for egg counts, Mini-FLOTAC FS2 reported 904 eggs per gram of faeces (EPG) for H. nana (vs 457 with McMaster and 111 with Kato-Katz) and 1177 EPG for A. lumbricoides (vs 1315 with Kato-Katz and 995 with McMaster); FS2 detected the highest EPG for both H.nana and A.lumbricoides (904 vs 568 and 1177 vs 643 respectively), the differences were not statistically significant. The technique feasibility was calculated: Kato-Katz mean time was 48 minutes/sample, Mini-FLOTAC 13 minutes/sample and McMaster 7 minutes/sample. However, especially for Kato-Katz and Mini-FLOTAC, the mean time (min/sample) decreased significantly when processing multiple samples.
  
  
  CONCLUSIONS
  Mini-FLOTAC is a promising technique for helminth diagnosis, it is more sensitive than Kato-Katz and McMaster for H. nana and as sensitive as Kato-Katz and more sensitive than McMaster for A. lumbricoides identification. Egg counts differences although relevant, did not reach statistical significance.
authors.affiliation: Laboratory of Microbiology San Raffaele Hospital, Milan, Italy. Beatrice.barda@gmail.com.
authors.forename: Beatrice
authors.initials: B
authors.lastname: Barda
authors.forename: Pamela
authors.initials: P
authors.lastname: Cajal
authors.forename: Eliana
authors.initials: E
authors.lastname: Villagran
authors.forename: Ruben
authors.initials: R
authors.lastname: Cimino
authors.forename: Marisa
authors.initials: M
authors.lastname: Juarez
authors.forename: Alejandro
authors.initials: A
authors.lastname: Krolewiecki
authors.forename: Laura
authors.initials: L
authors.lastname: Rinaldi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Cringoli
authors.forename: Roberto
authors.initials: R
authors.lastname: Burioni
authors.forename: Marco
authors.initials: M
authors.lastname: Albonico
mesh_terms: D000293:Adolescent; D000818:Animals; D001118:Argentina / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005243:Feces / Q000469:parasitology*; D005260:Female; D006373:Helminthiasis / Q000175:diagnosis* / Q000453:epidemiology*; D006376:Helminths / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D010063:Ovum / Q000166:cytology; D010270:Parasite Egg Count; D012680:Sensitivity and Specificity