Diagnosing Parasites: Why Lab Testing in the U.S. Is Not More Reliable
. . . and Is Better Elsewhere
by Dr. Glenn Wilcox, D.O.M.
The accuracy of conventional lab tests for parasites in the United States is medically frustrating for me and many of my colleagues. This opinion has been expressed to me over the past four decades by many medical professionals who have made the effort to better inform themselves and stepped beyond the established, conventional medical stance. It has certainly been my experience. But why would this be so in the twenty-first century, a time when we have mapped the human genome and made huge strides determining the extent and influence of the human microbiome?
Parasitology Diagnosis History: “Currently, the detection and diagnosis of parasite infections rely on several laboratory methods in addition to clinical symptoms, clinical history, travel history, and geographic location of patient. The primary tests currently used to diagnose many parasitic diseases have changed little since the development of the microscope in the 15th century by Antonie van Leeuwenhoek.”(1)
Expertise: Generally, a Ph.D. directs a lab, but the microscopy is usually performed by a lab tech. A lab tech has a minimal education in identifying parasites, and this is not expertise. It requires 3 to 5 years to attain entry level expertise as a parasitologist. Furthermore, the expertise of the directing parasitologist varies greatly depending on where they were educated. As in all areas of medicine and life, parasitologist competency varies widely. It is important to understand that it is rare for an actual worm to show up in a stool specimen. Diagnosis is made by identifying very small, microscopic metazoan parasite ova (eggs), and protozoan cysts (immature) or trophozoites (mature). Identifying pathogens by microscopy is a rigorous science. Evidence of a parasite infection can easily be missed due to lack of expertise.
Laboratory Methodology: Laboratory methodology varies from lab to lab. It takes time, and time is money. The lab often does not take the time to do the methodology for identifying parasites thoroughly. This methodology includes many steps: physical examination, concentration techniques, filtering, centrifuging, washing, transferring from one tissue to another, and one CF (dye) to another, separation of fibers, preparation of slides, etc. Finally, the ability to identify the parasites at various levels is essential. In the U.S., those doing the microscopy often do not have the level of expertise required.
CLIA: Through the Clinical Laboratory Improvement Amendments (CLIA), the Centers for Medicare & Medicaid Services (CMS) regulates all laboratory testing (except research) performed on humans in the U.S. (However, CLIA has no direct Medicare or Medicaid program responsibilities.) CLIA certifies clinical laboratories but does not guarantee accuracy of testing by the certified lab.
Time: As part of my research to try to understand why labs in the U.S. are not doing a good job finding most parasites in standard ova and parasite tests, I decided to ask lab techs about what goes on. So, I invited a few out, individually, for a meal. What I learned was interesting, and while frustrating, their responses were consistent with most profit-motivated businesses. Simply stated, the techs told me, off the record, that management made it clear that minimal time was to be spent doing hands on microscopy since the lab made more money with automated procedures. And so, I asked a friend who had a friend who was a lab manager to discretely inquire. The lab manager told my friend that corporate sent down the same word. These are the simple facts of life in our society. Therefore, the appropriate time needed to perform accurate parasitology microscopy may not be allowed for, and of course this will interfere with getting accurate results.
Conventional Medical Opinion: Several years ago, I taught a four-hour introductory class about parasites to health professionals and consumers. There were four M.D.s in the class. When the class was finished each of the M.D.s told me they had learned more about the subject in this short class than in their entire medical education. Medical students get a few hours of introductory education in parasitology, usually as part of an infectious disease course.
“According to Acholonu (2003), in USA, there is de-emphasis of parasitology in the medical and veterinary schools, but more so in medical schools. A survey carried out revealed that there is not a single department of parasitology in medical schools in the USA.”(2)
Unfortunately, the conventional medical belief is that parasite infections are a third world problem and not at all common in “clean” America. In fact, what I have learned while specializing in treating parasites since 1980 and working closely with a world-class parasitologist for three decades is that it is a very common problem in the U.S. In fact, a recent, large study about the prevalence of intestinal parasites in the U.S. was reported in the American Journal of Tropical Medicine and Hygiene in 2002. “One-third of 5,792 fecal specimens from 2,896 patients in 48 states and the District of Columbia tested positive for intestinal parasites during the year 2000…”(3)
Obviously, many of us travel to other countries where our chance of being infected increases. And, much of our food comes from those countries. Parasite cysts and eggs can be on vegetables and fruit as well as unhealthy bacteria. Furthermore, for example, it is understood by the U.S. Centers for Disease Control (CDC) that normal municipal water purification does not completely eliminate parasites like Giardia and Cryptosporidium from our drinking water or the water used to wash and keep fresh looking vegetables in the store. In America, is our water safe to drink and our food safe to eat? Sometimes… But not always! Drinking water that has not been purified by reverse osmosis or eating raw vegetables (salad!) without first soaking them in a dilute hydrogen peroxide bath is quite simply a gamble. The risks may be less in the U.S., but they are very real.
Pharmaceutical Company Interests: Obviously, pharmaceutical companies make billions of dollars selling prescription and over-the-counter medicines to temporarily and continually relieve all manner of digestive complaints, and making a profit is their prime directive. Why eliminate the cause of the problem, if doing so would reduce recurring profits? Medical and pharmacology schools are funded in large part by pharmaceutical companies. Is it possible there is a motivation to not support parasitology departments or courses?
Non-objective Evaluation of Parasites: Many health care professionals, from medical doctors to massage therapists, are aware that parasite infections are a real problem in the U.S., and they are frustrated by the lack of accurate diagnosis. So, some resort to testing that is considered non-objective. Examples are: pulse diagnosis in oriental and ayurvedic medicine; kinesiology or muscle testing, electro-diagnostic equipment, etc. While these methods can be helpful for general screening, I have not found them to provide sufficient, specific, parasite diagnostic accuracy at the professional level I need for the health of my patients. Some just grope in the dark and have their patients take a drug or natural medicine in the hopes that it will eliminate the infection without doing any testing. I have not found this to be a wise and reliable choice.
DNA Testing: DNA testing for parasites is evolving rapidly. While this method of parasite diagnosis is not fully mature currently, the promise for the future is exciting. Here’s an example of recent problems with DNA testing. In 2007, Metametrix, a well-known, CLIA licensed, diagnostic laboratory began offering a stool-screening test that used a proprietary DNA method reported as “DNA/ELISA” in an effort to identify stool microbia (pathogens including parasites). Many docs used this test. To test the accuracy and specificity of this method, and unknown to Metametrix, an external proficiency analysis study was conducted by an independent research institution. Results revealed that there was a significant discrepancy between the results found in the study and those of the reports of the same specimen from Metametrix. In simple words, the DNA test was very inaccurate. On July 11, 2012, Genova Diagnostics, Inc. (formerly Great Smokies Diagnostic Laboratories) announced the acquisition of Metametrix, Inc. On June 18, 2012, the results of the independent study were presented at the 112th General Meeting of the American Society of Microbiology.(4)
One day your smartphone may have an attachment that will immediately analyze a sample of your morning BM, and you will know if you have uninvited guests. Until then, I will continue to send specimens to the world-class lab I use in Africa that I’ve depended on for decades and that has helped me to truly eliminate parasite infections from my patients and those of other health care professionals I work with.
Hammed Ibraheem, M.D., Ph.D.: Since 1988, I have worked closely with my mentor Dr. Hammed Ibraheem, a world-class parasitologist and brilliant medical doctor. Since 1988, I have worked closely with my mentor Dr. Hammed Ibraheem, a world-class parasitologist and brilliant medical doctor. He has been a member of the World Health Organization (WHO) since 1971 and is the founder of EKO University of Medical and Health Sciences in Lagos, Nigeria (https://ekounimed.edu.ng). It is the premiere medical university in Nigeria and is emerging as the top school in Africa. It enjoys an affiliation with Columbia Medical School in New York City, and graduates may sit for U.S. foreign M.D. equivalency exams. There is a hospital on the Eko University campus. EKO University also offers a post graduate program in parasitology, and many other specialties. EKO University has a strong memorandum of understanding with Lagos State Government and is fully accredited by the Federal Republic of Nigeria. The EKO University and Hospital Lab is a world-class facility. This is where I send my patient’s specimens and those of other doctors’ patients for accurate diagnosis.
Who Is Willing to Work with Feces? Over a decades-long career in parasitology and as a result of teaching the subject to students wanting to specialize in the field, Dr. Hammed Ibraheem has observed what may be the fundamental issue. Whether a parasitology student, a lab tech, or a Ph.D. parasitologist “Many people run away from fecal waste. They don’t want to touch a stool sample, even if it comes from their own rear end.”(5) This simple fact of life may be the most revealing bottom line about why parasite diagnosis is not more reliable.
505-771-4998 — www.DrGlennWilcox.com
REFERENCES
- How parasitology is taught in medical… Article in Parasitology Research 105(6):1759-62 · September 2009, DOI: 10.1007/s00436-009-1594-7, Available: https://www.researchgate.net/publication/26757482_How_parasitology_is_taught_in_medical_faculties_in_Europe?_Parasitology_lost
- Interdisciplinary Perspectives on Infectious Diseases, Volume 2009, Article ID 278246. “Diagnosis of Parasitic Diseases: Old and New Approaches,” a review article by Momar Ndao, National Reference Centre for Parasitology, McGill University Centre for Tropical Diseases, Montreal General Hospital, 1650 Cedar Avenue R3-137, Montreal, QC, Canada H3G 1A4 http://dx.doi.org/10.1155/2009/278246
- Amin, 0. 2002. Seasonal Prevalence of Intestinal Parasites in the United States during 2000, American Journal of Tropical Medicine and Hygiene 66(6):799-803).
- Gingras BA, Duncan SB, Schuyeller NJ, Schreckenberger PC. Assessment of the Diagnostic Accuracy of Recently Introduced DNA Stool Screening Test. Astr. 112th Gen. Mtg. Am. Soc. Microbiol., San Francisco, CA June 18, 2012.
- Quoted from a personal conversation on 06/03/18 with Dr. Hammed Ibraheem by Dr. Glenn Wilcox.