Antimicrobial susceptibility of bacterial isolates from 233 horses with musculoskeletal infection during 1979–1989

Abstract

Summary Bacterial culture and susceptibility results were analysed from 233 horses with septic arthritis/tenosynovitis or osteomyelitis that developed after fracture repair. Antibiotics were deemed highly effective, effective or ineffective if ≤85%, 70–84.9% or <70% of the isolates were susceptible respectively. In total, 424 bacterial types were isolated; 386 were aerobic or facultative and 38 were anaerobic. Enterobacteriaceae (28.8%) were the most common bacterial group isolated, followed by non‐beta‐haemolytic streptococci (13.0%), coagulase‐positive staphylococci (11.8%), beta‐haemolytic streptococci (9.4%), and coagulase‐negative staphylococci (73%). The remainder of the organisms were other Gram‐negative (15.8%), other Gram‐positive (2.3%) and miscellaneous (2.6%) bacteria. Penicillin and ampicillin were highly effective against beta‐haemolytic streptococci, but were ineffective against other bacteria. Ampicillin was no more effective than penicillin against most bacteria. Amikacin was the most effective antibiotic against the wide range of bacteria isolated in this study. Amikacin was highly effective against coagulase‐positive staphylococci, Enterobacteriaceae and Pseudomonas and was effective against coagulase‐negative staphylococci and Actinobacillus. Gentamycin was not highly effective against any bacterial group; but was effective against coagulase‐positive and negative staphylococci, Pseudomonas, Salmonella and Actinobacillus. Kanamycin was ineffective against all bacteria with the exception of Actinobacillus. Cephalothin was highly effective against beta‐haemolytic streptococci, coagulase‐positive staphylococci and Actinobacillus and was effective against coagulase‐negative staphylococci. Cephalothin is a very useful antibiotic for Gram‐positive organisms, especially staphylococci, which are an important cause of iatrogenic infections. Trimethroprim‐sulphonamides were highly effective against Actinobacillus and were effective against coagulase‐positive staphylococci, beta‐haemolytic streptococci, non‐beta‐haemolytic streptococci and Rhodococcus equi. Due to the narrow spectrum of activity of trimethoprim‐sulphonamides against the common pathogenic organisms, these drugs should be used only after culture and susceptibility results are known. Erythromycin was highly effective against coagulase‐positive staphylococci, beta‐haemolytic streptococci and Rhodococcus equi and was effective against coagulase‐negative staphylococci. Chloramphenicol was effective against a wide range of organisms, but it cannot be recommended because of the human health hazard associated with handling this drug. Other less commonly used antibiotics were effective against some types of bacteria. The combination of a cephalosporin and amikacin provides the best coverage against the bacteria isolated in this study. These are the antibiotics that should be considered when treating horses with musculoskeletal infection before culture and susceptibility results are known. However, these drugs are not recommended for prophylaxis in ...

Clinical use of antimicrobial regional limb perfusion in horses: 174 cases (1999–2009)

“…Amikacin was the antimicrobial most commonly used for RLP, probably because of its highest activity against pathogens isolated from equine orthopedic infections. 23,24 Bacterial culture and antimicrobial susceptibility testing were performed on admission in most horses in group 1, but A-RLP was typically started before the laboratory results became available. Antimicrobial doses varied widely, which is commonly observed in the literature.…”

Distal limb perfusion with amikacin in two horses

“…Έτσι, αντι-μικροβιακές ουσίες, όπως π.χ. η κλινδαμυκίνη, που υφίστανται περιορισμούς στη χρήση τους συστηματικά (Moore 1992), μπορούν να χρησιμοποιηθούν κατά την DLP με ασφάλεια (Santschi et al 1998, Errico et al 2008. Επιπλέον, αυτή η πιθανότητα εμφάνισης παρε νεργειών κατά τη συστηματική χορήγηση αυξάνεται καθώς, στις περισσότερες περιπτώσεις, γίνεται ταυ τόχρονη χρήση μη στεροειδών αντιφλεγμονωδών φαρμάκων, που επίσης ενοχοποιούνται για ανεπιθύ μητες συστηματικές παρενέργειες (νεφροτοξικότητα, ηπατοτοξικότητα και δημιουργία ελκών στον πεπτικό σωλήνα) (Rubio-Martinez et al 2005).…”

“…Τέλος, οι μεγάλες ποσότητες αντιβιοτικών που απαιτούνται για την ενδοφλέβια συστηματική θερα πεία σε έναν ίππο, σε συνδυασμό με το κόστος ορι σμένων αντιβιοτικών ουσιών, αυξάνουν σημαντικά το κόστος της θεραπείας, γεγονός το οποίο αποφεύγεται κατά την DLP (Moore et al 1992, Murphey et al 1999, Rubio-Martinez et al 2005). …”

“…Όπου είναι δυνατό, θα πρέπει να γίνεται καλλιέργεια υλικού από τη σηπτική εστία και αντιβιό γραμμα πριν από την έναρξη της θεραπείας (RubioMartinez and Cruz 2006). Σε περίπτωση που δεν υπάρ χει αυτή η δυνατότητα, η επιλογή βασίζεται στους συ χνότερα ανευρισκομενους μικροοργανισμούς στις μυοσκελετικές λοιμώξεις και στην πηγή από την οποία προέρχεται η μόλυνση (Moore et al 1992). Οι συχνό τερα ανευρισκόμενοι μικροοργανισμοί στις μυοσκε λετικές λοιμώξεις των ίππων είναι αυτοί της οικογέ νειας των εντεροβακτηριδίων.…”

“…Οι συχνό τερα ανευρισκόμενοι μικροοργανισμοί στις μυοσκε λετικές λοιμώξεις των ίππων είναι αυτοί της οικογέ νειας των εντεροβακτηριδίων. Ακολουθούνται από τους στρεπτόκοκκους, β-αιμολυτικούς και μη, και τους σταφυλόκοκκους, πηκτάση-θετικούς και αρνητικούς (Snyder et al 1987, Moore et al 1992. Η αυξημένη συχνότητα ανεύρεσης των εντεροβακτηριδίων αποδί δεται στο περιβάλλον των ίππων και κυρίως στην επι μόλυνση από το έδαφος και τα κόπρανα τους (Snyder et al 1987).…”