Parasitic gut infections.

Emerging spore-forming protozoa such as cryptosporidia and microsporidia are becoming major public health problems in developing countries as well as in the developed world. They are a new addition to an already long list of intestinal parasites, but their diagnosis is much more difficult than for well-known protozoa and helminths. Fortunately, enzyme immunoassay and polymerase chain reaction techniques are becoming available not only for the detection of Cryptosporidium parvum and the microsporidia, but also for Entamoeba histolytica and Giardia lamblia. These assays are not only increasing the sensitivity of detection but are also allowing, for the first time, species differentiation such as Entamoeba histolytica/dispar or Encephalitozoon intestinalis/Enterocytozoon bieneusi.