Hydrocortisone therapy in a cat with vasopressor-refractory septic shock and suspected critical illness-related corticosteroid insufficiency

Pisano, Simone R. R.; Howard, Judith; Posthaus, Horst; Kovacevic, Alan; Yozova, Ivayla D.

Although CIRCI has mostly been associated with septic shock, other causes including traumatic brain injury and cancer have been reported in people [22] [23] [24] . Similarly, the previously reported case of feline CIRCI was a cat with polytrauma [18] . In addition, evidence of CIRCI based on ACTH-stimulation testing was found in critically ill cats with neoplasia [25] . Septic shock was likely the main cause of CIRCI in the cat reported here, but predisposing factors, including drug exposure should be considered [26, 27] . Megestrol acetate administration has been associated with metropathies [28] [29] [30] , and likely played a role in the development of pyometra in this cat. Moreover, MA administration may lead to reversible and potentially fatal HPA axis suppression in both humans and cats [31] [32] [33] [34] , thereby implicating it in the development of CIRCI itself. However, adrenocortical recovery after MA administration (2.5 mg/cat q24 h or 5 mg/cat q48 h for 2 weeks) was found to only require 2-4 weeks [34] [35] [36] . The cat in the present report received a similar dose and the last dose reported by the owner was 8 weeks prior presentation. Even if the owner was mistaken about the timing of the last dose of MA, basal cortisol would be expected to be <1 lg/mL in MA-induced HPA axis suppression [34] , but basal cortisol measured in this cat was elevated. Moreover, hydrocortisone therapy is considered necessary in people with CIRCI regardless of cause, and treatment response in this cat is evidence of CIRCI responding to hydrocortisone whether or not MA played a role in its development [33] .