Encephalitozoonosis in 2 South American Fur Seal (Arctocephalus australis) Pups

Cerebral and disseminated encephalitozoonosis was diagnosed by histopathology, electron microscopy, and immunohistochemistry in 2 free-ranging South American fur seal pups found dead at Guafo Island (43°33′S 74°49′W) in southern Chile. In the brain, lesions were characterized by random foci of necrosis with large numbers of macrophages containing numerous microsporidial organisms within parasitophorous vacuoles. In addition, occasional histiocytes loaded with numerous mature and immature microsporidia spores consistent with Encephalitozoon sp were observed in pulmonary alveolar septa, splenic red pulp, glomerular capillaries, and proximal renal tubules by Gram and immunohistochemical stains. To our knowledge, microsporidial infection in a marine mammal species has not been previously reported.

[1]  J. Larsson,et al.  Structure of Microsporidia , 2014 .

[2]  K. Bateman,et al.  Microsporidia: diverse, dynamic, and emergent pathogens in aquatic systems. , 2013, Trends in parasitology.

[3]  B. Sak,et al.  Humoral immune response and spreading of Encephalitozoon cuniculi infection in experimentally infected ponies. , 2013, Veterinary parasitology.

[4]  B. Sak,et al.  Latent Microsporidiosis Caused by Encephalitozoon cuniculi in Immunocompetent Hosts: A Murine Model Demonstrating the Ineffectiveness of the Immune System and Treatment with Albendazole , 2013, PloS one.

[5]  T. Eisenberg,et al.  Encephalitozoonosis in two inland bearded dragons (Pogona vitticeps). , 2013, Journal of comparative pathology.

[6]  K. Matiasek,et al.  Value of histopathology, immunohistochemistry, and real-time polymerase chain reaction in the confirmatory diagnosis of Encephalitozoon cuniculi infection in rabbits , 2013, Journal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc.

[7]  F. Henríquez,et al.  Pathological findings in South American fur seal pups (Arctocephalus australis gracilis) found dead at Guafo Island, Chile. , 2011, Journal of comparative pathology.

[8]  R. López-Vélez,et al.  In Vitro Culture, Ultrastructure, Antigenic, and Molecular Characterization of Encephalitozoon cuniculiIsolated from Urine and Sputum Samples from a Spanish Patient with AIDS , 2001, Journal of Clinical Microbiology.

[9]  K. Wasson,et al.  Mammalian Microsporidiosis , 2000, Veterinary pathology.

[10]  L. Weiss,et al.  The Microsporidia and Microsporidiosis , 1999 .

[11]  R. Belknap,et al.  Physiological, demographic and pathological changes in wild Norway rat populations over an annual cycle. , 1972, Comparative biochemistry and physiology. A, Comparative physiology.