title: Mycobacterium chelonae associated with tumor-like skin and oral masses in farmed Russian sturgeons (Acipenser gueldenstaedtii).
abstract: BACKGROUND
  Non-tuberculous mycobacteria responsible for piscine mycobacteriosis usually produce visceral granulomas in both freshwater and marine species. In this study, the first occurrence of Mycobacterium chelonae associated with tumor-like lesions in the Russian sturgeon (Acipenser gueldenstaedtii) is reported. Fifteen sturgeons from an Italian fish farm showing skin and oral cauliflower-like masses were investigated by histopathology, bacterial culture and molecular analyses.
  
  
  RESULTS
  A total of 20 masses different in size located in the mouth and in pectoral and caudal fins (characterized by abundant calcium deposits and by mild to moderate granulomatous inflammation) were observed with a significant different degree of histological severity. All internal organs of the fish were negative for mycobacteria, Ziehl-Neelsen was positive in only one of the oral masses, whereas bacterial and PCR analyses detected the presence of M. chelonae for almost all the skin and oral masses. Based on these results, a calcinosis of dystrophic origin associated with a chronic granulomatous inflammation was considered as a primary diagnosis consequent to tissue injury in areas susceptible to trauma.
  
  
  CONCLUSIONS
  We hypothesized that the occurrence of M. chelonae in farmed sturgeons was only a secondary event related to its presence in a stressful rearing environment and subsequent to a dystrophic calcinosis occurred in previously damaged tissues.
authors.affiliation: Department of Veterinary Medicine, University of Sassari, Via Vienna 2, 07100 Sassari, Italy. eantuofermo@uniss.it.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Antuofermo
authors.forename: Antonio
authors.initials: A
authors.lastname: Pais
authors.forename: Sara
authors.initials: S
authors.lastname: Nuvoli
authors.forename: Udo
authors.initials: U
authors.lastname: Hetzel
authors.forename: Giovanni P
authors.initials: GP
authors.lastname: Burrai
authors.forename: Stefano
authors.initials: S
authors.lastname: Rocca
authors.forename: Monica
authors.initials: M
authors.lastname: Caffara
authors.forename: Ilaria
authors.initials: I
authors.lastname: Giorgi
authors.forename: Claudio
authors.initials: C
authors.lastname: Pedron
authors.forename: Marino
authors.initials: M
authors.lastname: Prearo
mesh_terms: D000818:Animals; D002118:Calcium; D005393:Fish Diseases / Q000382:microbiology* / Q000473:pathology; D005399:Fishes; D009059:Mouth Diseases / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D009165:Mycobacterium Infections, Nontuberculous / Q000382:microbiology / Q000662:veterinary*; D016926:Mycobacterium chelonae / Q000302:isolation & purification*; D017192:Skin Diseases, Bacterial / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*
chemical_list: D002118:Calcium