Zoonotic anatrichosomiasis in an Illinois resident

Abstract

We describe a case of zoonotic anatrichosomiasis in a patient from Illinois. A 44-year-old immigrant from Mexico originally presented with a history of multiple oral ulcers and two submucosal nodules on the dorsal surface of the tongue. An incisional biopsy was taken to assist with diagnosis. Examination of stained sections revealed the presence of a coiled nematode. The histologic examination displayed trichuroid features. Anatomic structures that aided in the identification included esophagus embedded in a prominent stichosome in the anterior end, paired bacillary bands, and small size. The location of the worm within the oral mucosal epithelium also facilitated the diagnosis.

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.

Figure 2.

Track-like lesions seen on the inner cheek. This figure appears in color at www.ajtmh.org.

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.

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 nature of the muscle cells and cuticle are also visible. Scale bar = 25 µm. This figure appears in color at www.ajtmh.org.

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.