Mycobacterium chelonae associated with tumor-like skin and oral masses in farmed Russian sturgeons (Acipenser gueldenstaedtii)

Abstract

BackgroundNon-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.ResultsA 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.ConclusionsWe 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.

A survey of bacterial infections in sturgeon farming in Italy

“…Costinar et al (2010) Pseudomonas fluorescens Brunetti et al (2006) Pseudomonas putida Kayis et al (2017) Streptococcus dysgalactiae subsp. equisimilis Salogni et al (2010) Vibrio alginolyticus Costinar et al (2010) Yersinia ruckeri Vuillaume et al (1987) Acipenser gueldenstaedtii Aeromonas hydrophila Timur et al (2010) Acinetobacter baumanii Kozińska, Paździor, Pękala, and Niemczuk (2014) Acinetobacter johnsonii Kozińska et al (2014) Acinetobacter radioresistens Kayis et al (2017) Citrobacter freundii Kayis et al (2017) Flavobacterium hydatis Timur et al (2010) Flavobacterium johnsonae Bauer, Pugachev, and Voronin (2002) Mycobacterium chelonae Antuofermo et al (2014) Mycobacterium salmoniphilum Righetti et al (2014) Pseudomonas fluorescens Kayis et al (2017) Serratia spp. Kayis et al (2017) Acipenser oxyrinchus desotoi Flavobacterium columnare Altinok and Grizzle (2001) Acipenser oxyrinchus oxyrinchus Aeromonas salmonicida Mohler (2004) Acipenser persicus Aeromonas hydrophila Soltani and Kalbassi (2001) Acipenser ruthenus Aeromonas hydrophila Quaglio et al (2000) Acipenser schrenckii Aeromonas hydrophila Zhou et al (2015) Mycobacterium spp.…”

Identification of Mycobacterium chelonae from Lined Seahorse Hippocampus erectus and Histopathological Analysis

“…M. chelonae infection has also been reported in zebrafish Danio rerio, Japanese pufferfish Takifugu rubripes, Atlantic guitarfish Rhinobatos lentiginosus. Atlantic salmon Salmo salar, Yellow perch Perca flavescens, Yellow stingray Urobatis jamaicensis, and Russian sturgeon Acipenser gueldenstaedtii [25][26][27][28][29][30][31]. Although many fish species can be infected with M. chelonae, studies have shown that there are differences in susceptibility to M. chelonae among different species and even different lines of the same species [32].…”