title: Histochemical study of Encephalitozoon cuniculi spores in the kidneys of naturally infected New Zealand rabbits.
abstract: Encephalitozoon cuniculi is an important microsporidian pathogen that is considered an emergent, zoonotic, and opportunistic. It infects both domestic and laboratory rabbits, generating severe chronic interstitial and granulomatous nephritis with fibrosis and granulomatous encephalitis. Encephalitozoonosis is diagnosed in paraffin-embedded sections by examining the spores in the host tissues. The spores are difficult to observe when the samples are stained with hematoxylin and eosin (H&E), particularly when there is an inflammatory reaction and tissue damage. The spores are easily mistaken for other microorganisms, such as fungi (yeasts), protozoa, and bacteria. In our study, we used kidney samples from E. cuniculi-positive rabbits and employed 14 recommended histologic stains for detecting microsporidia spores: alcian blue, calcofluor white, Giemsa, Gram, Grocott, H&E, Luna, Luxol fast blue, Masson trichrome, modified trichrome stain (MTS), periodic acid-Schiff reaction (PAS), Van Gieson, Warthin-Starry (WS), and Ziehl-Neelsen (ZN).We concluded that MTS and Gram stain, detected by light microscopy, and calcofluor white stain, detected by ultraviolet light microscopy, are the best stains for detecting spores of E. cuniculi in paraffin-embedded tissues from infected rabbits. These stains were superior to WS, ZN, Giemsa, and PAS for identifying spores without background "noise" or monochromatic interference. Also, they allow individual spores to be discerned in paraffin-embedded tissues. MTS allows observation of the polar tube, polaroplast, and posterior vacuole, the most distinctive parts of the spore.
authors.affiliation: Cuerpo Académico de Zoonosis y Enfermedades Emergentes (Rodríguez, Villarreal, Nevárez, Castillo, Rodríguez, Navarro, Trejo), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Epidemiología Veterinaria (Zarate), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Patobiología (Hernández), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.
authors.forename: Luis E
authors.initials: LE
authors.lastname: Rodríguez-Tovar
authors.affiliation: Cuerpo Académico de Zoonosis y Enfermedades Emergentes (Rodríguez, Villarreal, Nevárez, Castillo, Rodríguez, Navarro, Trejo), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Epidemiología Veterinaria (Zarate), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Patobiología (Hernández), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.
authors.forename: Alejandra
authors.initials: A
authors.lastname: Villarreal-Marroquín
authors.affiliation: Cuerpo Académico de Zoonosis y Enfermedades Emergentes (Rodríguez, Villarreal, Nevárez, Castillo, Rodríguez, Navarro, Trejo), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Epidemiología Veterinaria (Zarate), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Patobiología (Hernández), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.
authors.forename: Alicia M
authors.initials: AM
authors.lastname: Nevárez-Garza
authors.affiliation: Cuerpo Académico de Zoonosis y Enfermedades Emergentes (Rodríguez, Villarreal, Nevárez, Castillo, Rodríguez, Navarro, Trejo), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Epidemiología Veterinaria (Zarate), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Patobiología (Hernández), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.
authors.forename: Uziel
authors.initials: U
authors.lastname: Castillo-Velázquez
authors.affiliation: Cuerpo Académico de Zoonosis y Enfermedades Emergentes (Rodríguez, Villarreal, Nevárez, Castillo, Rodríguez, Navarro, Trejo), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Epidemiología Veterinaria (Zarate), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Patobiología (Hernández), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.
authors.forename: Heidi G
authors.initials: HG
authors.lastname: Rodríguez-Ramírez
authors.affiliation: Cuerpo Académico de Zoonosis y Enfermedades Emergentes (Rodríguez, Villarreal, Nevárez, Castillo, Rodríguez, Navarro, Trejo), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Epidemiología Veterinaria (Zarate), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Patobiología (Hernández), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.
authors.forename: Magda C
authors.initials: MC
authors.lastname: Navarro-Soto
authors.affiliation: Cuerpo Académico de Zoonosis y Enfermedades Emergentes (Rodríguez, Villarreal, Nevárez, Castillo, Rodríguez, Navarro, Trejo), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Epidemiología Veterinaria (Zarate), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Patobiología (Hernández), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.
authors.forename: Juán J
authors.initials: JJ
authors.lastname: Zárate-Ramos
authors.affiliation: Cuerpo Académico de Zoonosis y Enfermedades Emergentes (Rodríguez, Villarreal, Nevárez, Castillo, Rodríguez, Navarro, Trejo), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Epidemiología Veterinaria (Zarate), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Patobiología (Hernández), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Hernández-Vidal
authors.affiliation: Cuerpo Académico de Zoonosis y Enfermedades Emergentes (Rodríguez, Villarreal, Nevárez, Castillo, Rodríguez, Navarro, Trejo), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Epidemiología Veterinaria (Zarate), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.|Cuerpo Académico de Patobiología (Hernández), Department of Immunology, FMVZ-UANL, Campus de Ciencias Agropecuarias, General Escobedo, Nuevo León, Mexico.
authors.forename: Armando
authors.initials: A
authors.lastname: Trejo-Chávez
mesh_terms: D000818:Animals; D000829:Animals, Domestic; D009670:Encephalitozoon cuniculi / Q000302:isolation & purification*; D016890:Encephalitozoonosis / Q000175:diagnosis / Q000469:parasitology / Q000662:veterinary*; D007668:Kidney / Q000469:parasitology; D011817:Rabbits; D012376:Rodent Diseases / Q000175:diagnosis* / Q000469:parasitology; D013172:Spores, Fungal / Q000302:isolation & purification*; D013194:Staining and Labeling / Q000662:veterinary
keywords: Chitin; Encephalitozoon cuniculi; Oryctolagus cuniculus; histochemistry; kidney; microsporidia; rabbits