Introduction and Review of the Literature
For many years the pathogenicity of Giardia lamblia has been questioned. While these organisms are usually harmless saprophytic flagellates, it has been thought by many that in heavy infestation they cause an interesting spectrum of disease. The asymptomatic carrier appears at one extreme and the full-blown celiac syndrome at the other. In between are all degrees of abdominal pain, anorexia, nausea and vomiting, malaise, melena, gallbladder colic, jaundice, malnutrition, and diarrhea.While the prevalence of Giardia lamblia infestation in children varies in different areas of the country, in most parts it exceeds 3%. In many areas of the southern United States2-5 it rises as high as 20%. It is the low prevalence of symptoms attributed to Giardia infestation by clinicians which has caused many parasitologists to doubt its pathogenicity.In support of the intermediate group in the spectrum of disease due to Giardia