Parasites in the human mouth
Just in case you found the hypnotoad parasitism case gross, here’s one to top that. BIO230 correspondent Heather G found a link via Wired online, which summarizes a report from the American Journal of Tropical Medicine and Hygiene. Most people would just gloss over the title “Gongylonema pulchrum Infection in a Resident of Williamsburg, Virginia, Verified by Genetic Analysis” without reading it at all, but those people would be missing out on a fascinating story.
Dr. Jonathan Allen felt something on the inside of his cheek one morning, and to his surprise it seemed that it moved under the skin back further into his mouth. Over the course of several months, it moved around in his mouth, until one day he was able to extract it with a very fine pair of forceps. He then transported it to the lab, determined the genetic identity of the worm by polymerase chain reaction and DNA sequencing, and then submitted a manuscript detailing the isolation and characterization of the worm. A review of the medical literature indicated that Gongylonema infections of humans are rare, with less than 50 cases ever noted worldwide. The typical route of infection is via accidental food-borne ingestion of contaminated insects, which represent the intermediate host of the nematode. Generally eggs are passed in the feces of an infected mammalian host, where they are taken up by insects. Fortunately in the case of Dr. Allen’s case, infection by his parasite was truly an end stage infection and the life cycle of the parasite was ended with his make shift surgical treatment.
Dr. Allen’s story related a sense of frustration in getting himself diagnosed. After being referred to an oral surgeon by his primary care physician at his initial complaint, the surgeon didn’t believe his self-diagnosis even after physical exam. This is poor medicine, particularly in light of this summary from another case study from the journal Clinical Infectious Diseases:
Clinicians, other health care providers, and microbiologists alike need to be alert to the possibility of infection with Gongylonema species. The characteristic clinical finding of a wormlike object migrating in the mouth area, including the buccal mucosa, gums, lips, or palate, should be a clear signal for consideration of Gongylonema infection in the differential diagnosis.