Renal medullary crest necrosis associated with phenylbutazone therapy in horses.

This study reports that using the drug phenylbutazone regularly in horses resulted in a condition known as renal medullary crest necrosis, which is similar to renal papillary necrosis seen in humans and rats.

Research Objective and Methodology

• The main aim of this research was to investigate the effects in horses of phenylbutazone therapy, particularly its association with renal medullary crest necrosis.
• For this investigation, 35 horse cases were studied, all of which had been receiving regular doses of phenylbutazone and showed evidence of renal medullary crest necrosis.

Findings

• The researchers discovered that the primary lesion in these cases was a well-defined focal medullary necrosis which resulted in the sequestration of fragments of the renal crest.
• Additional findings were the presence of renal cortical lesions, these were considered to be secondary to the medullary necrosis.
• These lesions displayed segmental pallor due to tubular dilatation, filtrate retention, and interstitial edema.

Conclusion

• The paper suggests ischemia, alongside phenylbutazone therapy, as the cause of this condition in horses.
• In the case of equine species, the research team argues that the term “renal medullary crest necrosis” is more appropriate for describing this condition than “renal papillary necrosis,” the term typically used in describing analogous conditions in humans and rats.