Renal dysfunction associated with infection of Leptospira interrogans in a horse.

This research article explores a case where a horse experienced kidney failure due to an infection from the bacteria Leptospira interrogans. The study provides clinical details of the case, diagnostic methods, and the resulting treatment and recovery.

Case Presentation

• The research describes a horse that suffered from kidney (renal) failure as a result of an infection of a particular bacterium known as Leptospira interrogans. This was identified through certain symptoms including fever, an increase in white blood cells (leukocytosis), the presence of pus in urine (pyuria), inability to concentrate urine (isosthenuria), and excessive urea and other nitrogenous waste products in the blood (azotemia).

Diagnostic Challenges

• The case was complex because, despite the presence of pus in the horse’s urine, no bacteria were observed in traditional microscopic examinations or in the urine cultures. This suggested an unusual inflammatory urinary tract disease that was difficult to diagnose.

Identification of Leptospira interrogans

• The illness was eventually identified when a fluorescent antibody test on the urine revealed the presence of Leptospira interrogans. This was confirmed by serologic testing (testing of the horse’s serum) over a six-month period which indicated an acute (sudden onset and typically a brief course) infection with a strain of the bacterium known as L. interrogans serovar pomona.

Treatment and Recovery

• The horse was treated with intravenously administered fluids and antimicrobial medications and this led to clinical recovery.

Concluding Remarks and Implications

• The bacteria Leptospira interrogans serovar pomona has been previously reported to cause fever, inflammation of the uvea of the eye (uveitis), or abortion in horses. However, this research draws attention to the fact that the bacterium can also lead to kidney failure in horses, highlighting the need for raised awareness and appropriate diagnosing of this disease in equine veterinary practice.