Which of these is a possible clinical sign of leptospirosis in dogs?

• A. Acute kidney injury
• B. Hair loss
• C. Severe pruritus only
• D. Hypergalactorrhea

Answer: (A)

Leptospirosis in dogs commonly affects the kidneys and liver, and acute kidney injury is a well-recognized clinical sign. The bacteria invade the renal tubules and interstitium, causing tubulointerstitial nephritis that impairs the kidney’s ability to concentrate urine, leading to azotemia. Clinically, this may present as dehydration, lethargy, vomiting, and changes in urination (polyuria or reduced urine output), and a urinalysis may show proteinuria with isosthenuria. While liver involvement can occur, other signs like hair loss, severe pruritus alone, or hypergalactorrhea are not typical features of leptospirosis in dogs. Thus, acute kidney injury fits the disease pattern and is a plausible, common sign.