Severe Hyperkalemia Secondary to Urethral Obstruction by a Plug in a Female Cat – Case Report

The urethral obstruction is a common urological emergency in feline medicine, typically associated with male cats due to their narrower urethral anatomy. In females, this condition is rare and usually linked to uroliths, with urethral plugs being uncommon. This report discusses a case of urethral obstruction in a 2-year-old female Brazilian Shorthair cat caused by a urethral plug associated with Feline Idiopathic Cystitis (FIC). The cat had a history of chronic stress related to environmental management issues, presenting clinical signs of periuria, pollakiuria, and hematuria for 15 days, which worsened over 24 hours. This progression led to lethargy, intense vocalization, urinary tenesmus followed by anuria, as observed by the owner. Consequently, the patient was referred to the intensive care unit (ICU), where alterations in vital parameters were noted, including 10% dehydration, hypothermia, mild hypotension, severe hyperkalemia, severe azotemia, hyperlactatemia, a feline grimace scale score of 5/10, and intense abdominal pain localized in the hypogastric region. The diagnosis of urethral obstruction was confirmed using abdominal ultrasonography, which revealed proximal urethral dilation and a material resembling dense organized sediment or a forming urolith, measuring approximately 4 mm x 2.1 mm. Following stabilization of the emergency condition, the patient underwent general anesthesia and epidural block, allowing immediate relief of the obstruction and placement of an indwelling urinary catheter. Post-procedure, the cat was maintained in intensive care, with significant improvement in renal biochemical and electrolyte abnormalities. Urethral obstruction in female cats is considered rare due to the distensible and wider nature of the urethra in this gender. When present, it is usually caused by uroliths and only rarely by urethral plugs. Therefore, this case highlights the importance of ultrasonographic diagnosis in female cats presenting with lower urinary tract signs and urinary tenesmus.