The patient is a 44-year-old Hispanic man who has lived in Illinois for 20 years. He grew up in Guanajuato, Mexico, which is in central Mexico about 150 miles north of Mexico City. He moved from Guanajuato about age 21 and then, worked in the California farm industry for 2 years. At that point, he moved to Illinois where he still resides. Recent travels include: Piedras Negra, Coahuila, Mexico in both July 2008 as well as July 2009. (Piedras Negra is just across the Rio Grande river from Eagle Pass, Texas); he also visited Guanajuato in January 2009. The patient currently works as a landscaper, although he has also worked in a foundry.
Medical history reported that he had been diagnosed with hypertension in the past but was not taking any systemic medications. He denied any medicinal or environmental allergies. Patient had initially seen his primary-care physician for symptoms. He had initially presented with a chief complaint of the feeling of a lump in his throat, although lesions on his tongue and lips began to appear early in the disease course. Lesions were reported to be relatively transient, lasting 4–5 days. The primary-care provider referred the patient to an otolaryngic specialist for further evaluation of throat symptoms. The otolaryngologist subsequently referred the patient to an oral pathology specialist with a differential diagnosis including cicatricial pemphigoid and viral disease. Various medications had been tried without benefit for the chief complaint, including esomeprazole for possible gastroesophageal regurgitation, topical fluocinonide and systemic prednisone for possible autoimmune ulcers, various antibiotics (azithromycin, amoxicillin, and amoxicillin with clavulonate), and nystatin for possible mycotic overgrowth.
At clinical presentation, the patient had what appeared to be multiple oral and lip ulcers, which appeared to be in the process of healing (), and two indurated submucosal nodules on the dorsal surface of the tongue that each measured approximately 4 mm in diameter. There were some possible tracks on the upper and lower lip lesions (). At time of biopsy, the clinical impression was that of chronic granulomatous disease versus amyloidosis. An incisional biopsy of the tongue was performed in an area that was somewhat indurated, and the patient said that he felt it was the newest area and felt that it would soon ulcerate.
Figure 1. One of several ulcerated lesions on the lip, some of which were in various stages of healing. This figure appears in color at www.ajtmh.org.
By time of biopsy, symptoms had been present for about 3 months. A tissue sample from the tongue biopsy was sent for routine histologic sectioning. Review of hematoxylin and eosin (H&E)-stained sections revealed the presence of a coiled female nematode lying under and within the epithelial mucosa ().
Figure 3. The coiled, non-gravid female worm is clearly visible in the sections of the tongue biopsy. At this magnification, some features of the worm, notably the stichocytes, are evident. Scale bar = 200 µm. This figure appears in color at www.ajtmh.org (more ...)
A more detailed study of the worm provided the following morphologic features that were compatible with a diagnosis of Anatrichosoma spp. The maximum diameter, measured in the region of the reproductive tube, was no more than 70 µm; stichocytes were prominently visible in the anterior end, even at lower magnification, and they contained the small tubular esophagus, the presence of two bacillary bands and compatible morphology of the muscle cells, and the reproductive tube ( and ).
Figure 4. Distinguishing morphologic features are clearly evident in this section and include bacillary bands in the lateral fields on both sides of worm (arrow to band on right side) and the small esophagus (arrowhead) embedded in the stichocyte (asterisk). The (more ...)
Figure 5. In these sections, posterior to the stichosome/esophageal region, the single female reproductive tube is visible, including infertile, undifferentiated eggs (arrows). Scale bar = 25 µm. This figure appears in color at www.ajtmh.org.
Although only a single worm was evident in the sections available for study, the impression at the time of examination was that multiple worms were likely present.
The patient was treated with 100 mg of mebendazole two times daily for 20 days, and a positive therapeutic outcome was achieved. All oral lesions resolved with no recurrence of symptoms with 1 month follow-up. At one point, the patient described skin lesions during mebendazole therapy, although they were thought by the patient's primary-care physician to be unrelated to the current discussion.