Fatal diarrhea caused by multidrug resistant Pseudomonas aeruginosa in a foal from Rio de Janeiro, Brazil

The present study evaluated the susceptibility pattern of one Pseudomonas aeruginosa isolate obtained from a deceased foal following an acute case of diarrhea. The isolate was identified by reference methods and tested with a panel of 27 antimicrobial agents. Pseudomonas aeruginosa was confirmed in pure culture and the isolate demonstrated resistance to all tested antimicrobials. Since it was a unique case in this herd, we suggest that contamination did not happen by horizontal transmission. The multidrug resistance was unexpected, associated to the virulence of the isolate, that killed the foal in five days, despite treatment.