title: Immunohistochemical identification of Encephalitozoon cuniculi in phacoclastic uveitis in four rabbits.
abstract: OBJECTIVE
  Encephalitozoon cuniculi is a microsporidium with a wide range of mammalian hosts. In rabbits it can be responsible for cataract and lens-induced uveitis (LIU). The aim of this study was to provide specific immunohistochemical demonstration and localization of E. cuniculi within the eye, in rabbits with LIU.
  
  
  METHODS
  Four rabbits were presented with a white mass in the eye and iris discoloration. Complete ophthalmic examinations were performed and a presumptive diagnosis of LIU was made in all cases. Initial therapy with a topical steroid, atropine and systemic enrofloxacin was instituted while serologic (IFA or ICA tests) and cytologic lab results were pending. The final outcome in all cases was enucleation. Routine histology and immunohistochemistry (ABC method) with an antiserum anti-Encephalitozoon cuniculi were performed.
  
  
  RESULTS
  Indirect immunofluorescence performed on one rabbit serum expressed a titer of 1 : 32; carbon immunoassay on the serum of the other three rabbits expressed a titer of 1 : 5120 in one, and a titer of 1 : 2560 in the other two cases. Histologically, an intraocular, locally extensive pyogranulomatous infiltration that partially filled the posterior chamber, encasing a wide anterior lens capsule break, was detected in all cases. Immunohistochemically, spores reacting with anti-Encephalitozoon cuniculi antiserum were present in all specimens, occasionally within macrophages and lens epithelial cells.
  
  
  CONCLUSIONS
  Detection of E. cuniculi in rabbits with phacoclastic uveitis has been investigated in the past with different methods. Based on our results, we suggest that immunohistochemistry should be regarded as a useful tool both for specific demonstration of E. cuniculi and for its localization within tissues.
authors: Veterinary Practice, C.so Duca degli Abruzzi, 10129 Torino, Italy. c.giordano@libero.it
authors: C
authors: C
authors: Giordano
authors: A
authors: A
authors: Weigt
authors: A
authors: A
authors: Vercelli
authors: M
authors: M
authors: Rondena
authors: G
authors: G
authors: Grilli
authors: C
authors: C
authors: Giudice
mesh_terms: D000818:Animals; D000953:Antigens, Protozoan / Q000032:analysis* / Q000097:blood; D003937:Diagnosis, Differential; D009670:Encephalitozoon cuniculi / Q000276:immunology*; D016890:Encephalitozoonosis / Q000097:blood / Q000175:diagnosis / Q000662:veterinary*; D005260:Female; D007150:Immunohistochemistry / Q000662:veterinary; D008297:Male; D011817:Rabbits; D014605:Uveitis / Q000175:diagnosis / Q000662:veterinary*
chemical_list: D000953:Antigens, Protozoan