Osteomyelitis and osteonecrosis after intraosseous perfusion with gentamicin.

This research describes complications that occurred after the use of gentamicin, an antibiotic, in horses to treat a blood infection. The findings suggest that the high doses of the drug caused damage to bone cells, leading to conditions such as bone inflammation and death of the bone tissue.

Introduction

• The study was undertaken to explore unexpected complications related to intraosseous infusion with gentamicin in horses.
• The patient in the case report was a ten-year-old Warmblood gelding that underwent the gentamicin perfusion treatment.

Methods

• The gentamicin was infused directly into the horse’s bone – specifically, the proximal phalanx (P1) – in order to treat the inflammation of the joint and navicular bursa.

Findings

• Although the blood infection improved, complications occurred at the site where the drug was infused.
• These complications consisted of persistent osteomyelitis (bone infection), progressive osteonecrosis (bone tissue death), and eventually a pathological fracture of P1 (abnormal breakage of the bone due to disease).

Interpretation

• The researchers concluded these complications were likely signs of toxic osteonecrosis caused by the drug infusion.
• It suggests that the high dose of gentamicin may have a harmful impact on equine mesenchymal cells (basic connective tissue cells in the bone of horses).

Conclusions

• The researchers indicate that further research is necessary to examine the effects of high dose gentamicin on equine mesenchymal cells when used in intraosseous perfusion.
• They also recommend considering either lowering the dosage of the drug infused into the medullary canal of P1 (the hollow interior of the bone), or choosing alternative infusion sites.