Comparison of methods for detecting Blastocystis hominis

Eur J Clin Microbiol Infect Dis. 2004 Jun;23(6):509-11. doi: 10.1007/s10096-004-1123-7. Epub 2004 May 28.


In order to determine the comparative sensitivity of two methods of detecting Blastocystis hominis and to investigate the seasonality of infection with this enteric protozoan parasite, the present study was conducted. In each of two 3-month periods representing winter, spring (February-April) and summer (July-September), 500 routine stool submissions were examined for B. hominis using microscopy following either formol-ether concentration or in vitro culture using Jones' medium. The organism was detected in 39 of the 1,000 samples investigated using the in vitro culture technique and in none of the samples using the formol-ether concentration technique. In 82% of the B. hominis-positive samples, no concurrent bacterial or parasitic pathogens were found, and diarrhoea was the most commonly recorded symptom among patients. Infection was more prevalent in summer than in winter/spring, occurring primarily in the 71-80-year age group. Cysts were detected in 20.5% of positive samples, but only following Ficoll-Paque concentration of formol-ether concentrates. Cyst excretion was more prevalent in summer than in winter/spring.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Distribution
  • Aged
  • Aged, 80 and over
  • Animals
  • Blastocystis Infections / diagnosis*
  • Blastocystis Infections / epidemiology
  • Blastocystis hominis / growth & development
  • Blastocystis hominis / isolation & purification*
  • Child
  • Child, Preschool
  • Culture Media
  • Feces / parasitology*
  • Female
  • Humans
  • Infant
  • Intestinal Diseases, Parasitic / diagnosis*
  • Intestinal Diseases, Parasitic / epidemiology
  • Male
  • Microscopy / methods
  • Middle Aged
  • Prevalence
  • Risk Factors
  • Sampling Studies
  • Sensitivity and Specificity
  • Severity of Illness Index
  • Sex Distribution
  • United Kingdom / epidemiology


  • Culture Media