According to Dr. Hermann R. Bueno of the Royal Society of Tropical Medicine and Hygiene in London, “parasites are the missing diagnosis in the genesis of many chronic health problems, including diseases of the gastrointestinal tract and endocrine system.” 1
While parasitic infection may be an underlying etiological factor in several chronic disease processes, doctors often do not consider the potential for parasitic involvement because signs and symptoms of parasitic infection often resemble those of other diseases. Moreover, it has been shown that parasite testing is a reasonable approach to the detection of causative agents for chronic gastrointestinal disorders. 2
Most Americans are inclined to believe that parasitic infection is a rare and exotic occurrence, limited to those who have traveled to distant, tropical lands. However, for a number of reasons, there has been an increase in the incidence of parasitic infection in this country. Reasons for this increase include the following: 3
Contamination of the water supply
Increased use of day care centers
Increased travel to, and visits from residents of countries where parasitic infection is endemic
Consumption of exotic and uncooked foods
The “sexual revolution”
Signs and symptoms of parasitic infection vary from one individual to another. The more common signs and symptoms are: constipation, diarrhea, bloating, gas, symptoms of irritable bowel syndrome, arthralgias, myalgias, anemia, increased allergic reactions, skin lesions, agitation and anxiety, difficulty with sleep, decreased energy, malnutrition and decreased immune function.
Infection can occur by four different pathways. These routes include contaminated food or water, insect vectors, sexual contact, and passage through the skin and nose. A thorough patient history will help assess the possibility of parasitic infection and the need for appropriate testing to confirm the suspicion. 4
Definitive diagnosis can be difficult because the life cycle of some parasites allows them to escape detection in standard tests. Interfering factors such as barium, bismuth, enemas, and antimicrobials such as antibiotics may further complicate detection of parasites in the stool. 5
1 Gittleman AL. Guess What Came to Dinner: parasites and your health . Garden City Park: Avery Publishing Groups Inc. 1993. p. ix.
2Zdero M, Cabrera G, Ponce de Leon P, et al. Parasitosis in an adult population with chronic gastrointestinal disorders. Acta Gastroenterol Latinoam . 1997;27(2):67-73.
3 Gittleman AL. Ibid. pp. 9-10.
4 Ibid., pp. 22-3
5 Ibid. p.93