Treatment of mycotic rhinitis caused by aspergillus fumigatus in a quarter horse mare using topical clotrimazole and oral potassium iodide.

The research article focuses on treating a horse suffering from mycotic rhinitis – a rare but severe fungal infection in the nasal passage – caused by a fungus called Aspergillus fumigatus. The treatment strategy presented employs topical clotrimazole and oral potassium iodide.

Introduction and Case Description

• The patient in question is a 7-year-old Quarter Horse mare with multiple symptoms including recurrent nasal discharge and bleeding, an unpleasant smell, a reluctance to exercise, and a previous incidence of abortion.
• The horse, weighing 325 kg, was diagnosed with fungal rhinitis and bacterial infection, involving β-hemolytic Streptococcus and Staphylococcus species, identified through lab tests and imaging examinations.
• Distinct features noted in the nasal passage included areas of erosion and scarring, purulent and bloody secretions, and striking yellowish plaques.
• Fungal culture and molecular diagnosis confirmed the involvement of Aspergillus fumigatus as the cause of the infection.
• Given the severity of the horse’s respiratory difficulties, a tracheostomy procedure was performed.

Treatment Approach and Progress

• The treatment initiated involved the topical application of clotrimazole ointment, applied daily in the rostral (front) part of the nasal cavity and every 48 hours in the caudal (back) part under endoscopic guidance.
• After five endoscopy-guided applications, the patient showed a noticeable improvement. However, the horse exhibited a hypersensitivity reaction to the clotrimazole, resulting in discontinuation of the treatment.
• At this point, the treatment regimen was switched to oral potassium iodide therapy, with a dosage of 67 mg/kg once a day for 14 days.

Results

• The patient exhibited a favorable clinical improvement and resolution of the fungal infection after 25 days of hospitalization.
• Topical clotrimazole demonstrated likely effectiveness as a standalone treatment, despite needing to be stopped early due to a hypersensitive reaction from the patient.
• The combination of clotrimazole with potassium iodide resulted in a more effective treatment outcome in a shorter span of time than that previously reported.

Conclusion

• While this report provides useful insights for other similar cases of fungal rhinitis in horses, it calls for additional studies to further validate the findings and approaches cited herein.