Microsporidial Keratoconjunctivitis in a Pet Bearded Dragon ( Pogona vitticeps )

Endoparasite Infections in Captive Inland Bearded Dragons (Pogona vitticeps) in Italy

The inland bearded dragon (Pogona vitticeps) is a lizard species commonly kept as a pet worldwide. Endoparasites are among the most important pathogens affecting bearded dragons. The aim of this study was to evaluate the endoparasites in captive P. vitticeps in Italy. Faecal samples from 30 P. vitticeps were analysed by fresh faecal smears, flotation tests, the Mini-FLOTAC technique, and a rapid immunoassay to detect Cryptosporidium spp. To search for microsporidia, PCR and sequencing were performed on the faecal samples. Data were statistically analysed. The overall positivity rate for endoparasites was 83.3% (25/30). The identified endoparasites were oxyurids (17/30, 56.7%), Isosospora amphiboluri (13/30, 43.3%), Encephalitozoon pogonae (4/18, 22.22%), and Cryptosporidium sp. (1/30, 3.33%). The positivity for protozoa was significantly higher in juveniles compared to adults. Moreover, the frequency of clinical signs was significantly higher in the positive animals. The results obtained here emphasize the importance of regular veterinary examinations of captive P. vitticeps, aimed at the diagnosis, treatment, and control of endoparasites. This study is one of the largest surveys on microsporidia infections in living bearded dragons, suggesting that E. pogonae may be widespread in this lizard.

Microsporidial stromal keratitis in a cat

A 12 year-old female spayed felid presented after a 35 day history of right eye pain. On examination, a sub-epithelial opacity was identified in the cornea. A lamellar keratectomy was performed and histopathological analysis revealed low numbers of 2x4um, Gram, Hamatoxylin-eosin and Gomori methanamine-silver positive spores. Transmission electron microscopy found ultrastructural findings consistent with the phylum Microspora. To the author's knowledge, this is only the second case of microsporidial stromal keratitis reported in a felid.

Intrapericardial Encephalitozoon pogonae-associated arteritis with fatal hemopericardium in two juvenile central bearded dragons

Two male juvenile central bearded dragons ( Pogona vitticeps) were submitted for postmortem examination after dying at their respective homes. Dragon 1 had marked hemopericardium with restrictive epicarditis. The inner aspect of the distended pericardial sac was lined by a fibrinoheterophilic membrane. In addition, granulomas abutted the testes. Dragon 2 had acute hemopericardium and granulomatous arteritis of the great vessels exiting the heart. Histologically, both animals had granulomatous arteritis of the large arteries with intrahistiocytic gram-positive, slightly elongated, up to 2 μm long microorganisms that contained a vacuole. These microorganisms were also present in the paratesticular granulomas. On transmission electron microscopy, the microorganisms were identified as microsporidians given the presence of exospore, endospore, vacuole, nucleus, and a filament with 4-6 coils. The microsporidia were identified as Encephalitozoon pogonae based on sequencing of the internal transcribed spacer 1 of the ribosomal RNA genes. Microsporidia are agents of disease in bearded dragons. Intrapericardial arteritis of large arteries with hemopericardium or restrictive epicarditis is a fatal manifestation of this infection.