Second Blog Assignment

Title: Shell Lesions Associated with Emydomyces testavorans Infection in Freshwater Aquatic Turtles. 

    The purpose of this study was to identify shell lesions associated with the fungi E. testavorans in freshwater turtles and to describe the morphology of these lesions (Woodburn, et al., 2021). 

Materials:

    There were 50 specimens of freshwater and semi aquatic turtle species and species of turtle shells included in this study. The shells that were selected for this study had to have the layers associated with healthy tissue layers (i.e., keratin layer, epidermis, dermis, and the shell portion which is made up of bone). Partial shells were not included in this study. The free-living turtles for this study resided in Florida and Washington of the United States (Woodburn, et al., 2021). 

 Methods:

    This study included three types of methods in order to identify lesions associated with E. testavorans. Grocott-Gomori’s methenamine silver or GMS was one of these methods to identify any lesion morphology and location associated with the fungi and also if there were fungi detected or not. If there was a presence of E. testavorans the specimens were marked as positive as shown in "Table 1: Signalment, Detection of Emydomyces Testavorans, and Associated Hisologic Lesions in Turtles Examined by Histopathology in this Study." (Woodburn, et al., 2021). The second method that was performed on 15 of the 50 specimen cases was the polymerase chain reaction or PCR. The third method that was used in this study was the formalin-fixed, paraffin-embedded or FFPE. Females, males and turtles of unidentified sex were recorded. In addition, juveniles, adults, and turtles of unidentified age were recorded. The turtles in this study represented 20 genera and 27 species. Morphological features of the shell tissues in the dermis, epidermis, and/or bone were recorded for each specimen. Location of these lesions were also recorded. “Epithelial inclusion cysts” termed by the authors in this paper were used to describe lesions with a cystic appearance that were embedded within the epidermis, dermis and bone and lined by stratified squamous keratinized epithelium. In addition, these cysts also contained necrotic tissue (Woodburn, et al., 2021). 

                                                            (Woodburn, et al., 2021)

Results:

According to Table 1, 24 cases there were reported lesions and were described as affecting the carapace and plastron scutes and were present in more than one location on the specimen. Some of the other recorded lesions included flaking of the scutes, discoloration of the scutes, thickening and excretions on portions of the plastron (Woodburn, et al., 2021). In 7 cases the lesions were recorded as nodules as seen in the picture below:

(Woodburn, et al., 2021)

Epithelial inclusion cysts were recorded in 28 cases. 29 cases tested by GMS method were identified as having E. testavorans. 17 cases tested by PCR method were identified as having E. testavorans. In addition, 6 cases via culture method were identified as having E. testavorans (Woodburn, et al., 2021). 

Critique:

Overall, this was a plausible paper. It was quite species inclusive as the cases of turtles ranged in 20 genera and 27 total species. Table 1 gives a thorough and extensive summary of the results found in this study. The tables were easy to understand and provided the right amount of information. In addition, the figures were well represented of what they were studying. More research is required for this particular topic in the future. 

References: 

Woodburn, D. B., Kinsel, M. J., Poll, C. P., Langan, J. N., Haman, K., Gamble, K. C., Maddox, C., Jeon, A. B., Wellehan, J. F. X., Ossiboff, R. J., Allender, M. C., & Terio, K. A. (2021). Shell Lesions Associated With Emydomyces testavorans Infection in Freshwater Aquatic Turtles. Veterinary pathology, 58(3), 578–586. https://doi-org.qe2a-proxy.mun.ca/10.1177/0300985820985217

Link to paper