RESUMO
OBJECTIVE: To describe a case of Waterhouse-Friderichsen syndrome of adrenocortical failure in a cat with Klebsiella spp. infection. CASE SUMMARY: A 12-year-old male neutered domestic short-haired cat was referred for respiratory failure requiring mechanical ventilation. The cat remained comatose despite successful weaning from the ventilator and developed a Klebsiella pneumoniae pneumonia. On day 4 of hospitalization, the cat acutely deteriorated with profound hypotension, azotemia, and hyperkalemia, which rapidly progressed to cardiac arrest. Necropsy findings revealed massive adrenal hemorrhage and intralesional bacteria, termed Waterhouse-Friderichsen syndrome. Waterhouse-Friderichsen syndrome was suspected to have been the cause of acquired adrenocortical insufficiency and sudden death of the cat. NEW OR UNIQUE INFORMATION: To the authors' knowledge, this is the first report of sepsis causing Waterhouse-Friderichsen syndrome in a veterinary species.