Nonsurgical resolution of renal cortical abscesses in a dog with multidrug-resistant Klebsiella-induced urosepsis

Background: Urinary tract infections caused by Klebsiella can significantly affect the renal parenchyma, with urosepsis being a potential outcome. Renal abscesses may also occur, and surgical interventions may often be required. This article reports a case of urosepsis and renal abscess caused by multidrug-resistant Klebsiella, describing a successful outcome of renal abscess resolution using antimicrobial therapy alone. Case Description: A 3-year-old female Shih-Tzu was referred to the intensive care unit of a teaching hospital in Brazil. The patient exhibited anorexia, vomiting, pale mucous membranes, jaundice, halitosis, hyperthermia, hypoglycemia, and hypotension. Stabilization included the administration of fluid resuscitation, vasopressor, antipyretic, and glucose. Laboratory findings included anemia, neutrophilic leukocytosis, thrombocytopenia, hyperfibrinogenemia, and elevated serum concentrations of creatinine, urea, phosphorus, alanine aminotransferase, alkaline phosphatase, and total and fractionated bilirubin. Abdominal ultrasonography revealed images compatible with chronic kidney disease (CKD) and renal abscesses. Empirical antibiotic therapy was initiated with enrofloxacin (5 mg/kg IV q 24 hours) and ceftriaxone (30 mg/kg IV q 12 hours), followed by a switch to meropenem (8.5 mg/kg SC q 12 hours for 10 days) based on positive urine culture results for Klebsiella spp. and susceptibility testing indicating sensitivity exclusively to carbapenems. The patient underwent peritoneal dialysis as renal replacement therapy. The treatment successfully resolved the uremic crisis, induced renal abscess regression, and reversed urosepsis. Conclusion: Conservative clinical management with antibiotic therapy proved effective in resolving urosepsis and abscesses located in the renal cortex, measuring approximately 4-5 cm, without the need for percutaneous drainage or surgical intervention. This finding highlights the need for further research into the efficacy of different therapeutic strategies based on the anatomical location of renal abscesses.