The influence of environmental bacteria in freshwater stingray wound-healing

Abstract

Invasion by bacteria can influence the course of healing of wounds acquired in aquatic environment. In this study, the bacteria present in Potamotrygon motoro stingray mucus and in the Alto Paraná river water were identified, and their ability to induce tissue injury and resist antibiotics was determined. Biochemical identification analysis showed that 97% of all bacterial isolates were Gram negative, Aeromonas spp., Enterobacter cloacae and Citrobacter freundii being the species most prevalent. Gelatinase and caseinase were produced by Aeromonas hydrophila, Aeromonas sobria and Pseudomonas aeruginosa strains. Erythrocyte hemolysis assay showed that A. sobria, A. hydrophila and to a lesser extent, other Gram-negative bacteria produced hemolysin. It was also observed that molecules released in culture by these bacteria were toxic to human epithelial cells. Antibiogram results showed that 68% of all bacterial isolates were resistant to at least one type of antibiotic, mainly B-lactams. Finally, it was demonstrated that although P. motoro venom was toxic to epithelial cells it did not influence bacterial proliferation. In summary, the results obtained in this work indicate that during the accident, the mucus of P. motoro and the environmental water may transfer into the wound pathogenic multi-resistant bacteria with the potential to cause severe secondary infections.

Aeromonas hydrophila induces intestinal inflammation in grass carp (Ctenopharyngodon idella): An experimental model

“…The exposure of open wounds to the bacterium is usually required for successful infection (Domingos et al, 2011). Bath exposure and the oral administration of A. hydrophila failed to induce intestinal inflammation in the grass carp and common carp (Schroers et al, 2009;Xu et al, 1987).…”

An efficient protocol for avoid sequelae over stingray sting injury

“…There is also risk of severe secondary infection by microbial population related to stingray's mucus. 4 Frequently, the injuries are compounded because the injured individual is not given proper first aids and does not seek medical help for appropriated care. 5 Thus, the total remission of symptoms can take months.…”

Hallux amputation after a freshwater stingray injury in the Brazilian Amazon

“…The most common agents in Potamotrygon motoro stingray mucus are gram-negative rods, namely Aeromonas spp., including B-lactam-resistant bacterial strains with the potential to cause severe secondary infection in stingray-acquired wounds (12) . In the present case, different antimicrobial regimens were employed throughout the different clinical stages of the case.…”