Controversies surrounding critical illness-related corticosteroid insufficiency in animals

[Inhalation therapy in dogs and cats with chronic lower airway disease - a literature review]

Chronic respiratory diseases are prevalent medical conditions in dogs and cats requiring lifelong treatment. Mainstay of therapy for chronic inflammatory respiratory diseases are glucocorticoids. Concurrent treatment with bronchodilators may be necessary to control clinical signs sufficiently. Due to the successful use in people as well as subsequent reduction of adverse effects of long-term glucocorticoid therapy, inhalative therapy has become increasingly important in veterinary medicine as well. Primarily spacers or valved holding chambers, in combination with metered dose inhalers, are used in dogs and cats. The technical properties of these devices, as well as their use and maintenance will be described in the following article. Furthermore, the existing literature regarding efficacy of inhalative medications for therapy of chronic inflammatory airway diseases in dogs and cats will be summarized.

Waterhouse-Friderichsen syndrome in a cat with Klebsiella spp. infection

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.

Retrospective evaluation of the use of hydrocortisone for treatment of suspected critical illness-related corticosteroid insufficiency (CIRCI) in dogs with septic shock (2010-2017): 47 cases

OBJECTIVE

To evaluate characteristics of septic shock patients treated with hydrocortisone (HC) due to suspicion of critical illness-related corticosteroid insufficiency (CIRCI) as compared to septic shock patients without suspicion of CIRCI.

DESIGN

Retrospective study between February 2010 and October 2017.

SETTING

University teaching hospital ICU.

ANIMALS

Data were collected for 47 dogs with septic shock. Twenty-one dogs were treated with HC (HC-treated) due to suspicion of CIRCI. Twenty-six dogs did not receive HC (non-HC-treated).

INTERVENTIONS

HC was administered either as an intermittent IV bolus or as a constant rate infusion (CRI) to those patients with suspected CIRCI.

MEASUREMENTS AND MAIN RESULTS

Significantly higher baseline APPLE_full scores and predicted mortality were detected in the HC-treated patients compared to non-HC-treated patients (0.87 vs 0.44 for predicted mortality, P = 0.039). Patients in the HC-treated group were on more vasopressors and cardiotonics than those in the non-HC-treated group (2.5 vs 1.5, P <0 .001). All patients initially responded to vasopressor administration, with average time to resolution of hypotension being 90 minutes for the HC-treated group compared to 60 minutes for the non-HC-treated group (P = 0.640). However, HC-treated patients took significantly longer to have a sustained resolution (a systolic blood pressure > 90 mm Hg or a mean blood pressure > 65 mm Hg for at least 4 h) of their hypotension after starting vasopressors, as compared to their non-HC-treated counterparts (8.5 vs 4 h, P = 0.001). Three (14.3%) HC-treated patients survived to discharge compared to 9 (34.6%) non-HC-treated patients, but this was not statistically significant.

CONCLUSIONS

HC-treated patients had a higher baseline risk of mortality than non-HC-treated patients. There was no significant difference in survival between the HC-treated and non-HC-treated septic shock patients. Further studies are needed to evaluate the use of HC in patients with suspected CIRCI.

Glucocorticoid metabolism in critically ill dogs (Canis lupus familiaris)

Critical illness due to sepsis is a major global health concern associated with a high burden of mortality and cost. Glucocorticoid dysregulation in human sepsis is associated with poorer outcomes. This study examines glucocorticoid metabolism in septic canine patients to delineate elements of cellular dysregulation in common with critically ill humans and explore potential differences. This was a prospective case-control study conducted in the veterinary specialist critical care departments of two University teaching hospitals. Critically ill canine patients with naturally occurring sepsis or septic shock were compared with an in-hospital control population. Serum total, bound, and free cortisol concentrations were increased in septic shock (P < 0.001), and higher bound cortisol was associated with nonsurvival (P = 0.026). Urinary Gas Chromatography-Tandem Mass Spectrometry was performed to assess urinary glucocorticoid metabolites and estimate intracellular glucocorticoid metabolism. Decreased renal 11β-hydroxysteroid dehydrogenase 2 (11βHSD2) activity inferred from increased urinary cortisol-to-cortisone ratio was observed in critically ill dogs (P < 0.001). Decreased 11βHSD2 activity (P = 0.019) and increased A-ring reduction of cortisone (P = 0.001) were associated with nonsurvival within the critically ill dogs. Intriguingly, two dogs were identified with low circulating total cortisol (<2 mg/dL) associated with increased A-ring reduction of cortisol, not previously described. Investigation of spontaneous canine sepsis and septic shock reveals dysregulation of cortisol to cortisone conversion similar to that observed in human patients, but with differences in A-ring reduction compared with those reported in humans. In addition, two dogs with high levels of cortisol inactivation associated with low circulating cortisol concentrations were identified.

Pseudohypoadrenocorticism in a Siberian Husky with Trichuris vulpis Infection

An entire male Siberian Husky presented for diarrhoea, weakness, inappetence, and collapse following a six-day period of illness. On clinical examination the dog displayed vasoconstrictive circulatory shock, dehydration, and melena. Laboratory tests revealed a marked hyponatraemia, hyperkalaemia, and a decreased sodium/potassium ratio of ≤ 12.4. The baseline and poststimulation serum cortisol concentrations were markedly elevated following adrenocorticotropin hormone (ACTH) stimulation test, yielding 712 nmol/L and 706 nmol/L, respectively. The elevated cortisol concentration excluded hypoadrenocorticism. A concurrent Trichuris vulpis (whipworm) infection was also identified. The dog was treated with supportive care including fenbendazole and recovered uneventfully. The final diagnosis was Trichuris vulpis infection with secondary pseudohypoadrenocorticism. This case report further supports a previous observation that the Siberian Husky breed may have an increased sensitivity to infection with Trichuris vulpis and development of pseudohypoadrenocorticism.

Comparison of initial treatment with and without corticosteroids for suspected acute pancreatitis in dogs

OBJECTIVES

To compare initial treatment with and without corticosteroids for acute pancreatitis in dogs and investigate the therapeutic efficacy and prognosis.

MATERIALS AND METHODS

Sixty-five dogs were included in this non-blinded, non-randomised clinical study. Dogs with acute pancreatitis received treatment either with dose of 1 mg/kg/day prednisolone (n=45) or without prednisolone (n=20). Response to treatment was based on changes in the C-reactive protein concentration, improvement in clinical signs, duration of hospitalisation, mortality and recurrence rate.

RESULTS

From the third day of hospitalisation, C-reactive protein concentration was significantly lower in the prednisolone group than that in the non-prednisolone group. The number of days required to reach a C-reactive protein concentration of <2 mg/dL and clinical score of ≤2 was significantly lower in the prednisolone group. The mortality rate 1 month after discharge was significantly lower in the prednisolone group (11.3% versus 46.1%).

CLINICAL SIGNIFICANCE

In dogs with acute pancreatitis, initial treatment with prednisolone resulted in earlier reductions in C-reactive protein concentration and earlier improvement of clinical signs.

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

A 27‐month‐old female cat was presented with septic peritonitis secondary to a ruptured pyometra and subsequent pyothorax. Vasopressor‐refractory septic shock led to a suspicion of critical illness‐related corticosteroid insufficiency, successfully treated with intravenous hydrocortisone. Previous megestrol acetate administration may have played a role in the development of adrenocortical dysfunction.

A review of associated controversies surrounding glucocorticoid use in veterinary emergency and critical care

OBJECTIVE

To review the literature in human and veterinary medicine regarding the indications for, efficacy of, and controversies surrounding glucocorticoid (GC) administration in the emergency and critical care (ECC) setting, and to provide an overview of the most commonly used synthetic GC formulations.

MEDICATIONS

Synthetic GCs vary in GC and mineralocorticoid potency, hypothalamic pituitary axis suppression, duration of action, route of administration, and clinical indication for use. Some of the GC compounds commonly used in human and veterinary ECC include hydrocortisone, prednisone, methylprednisolone, and dexamethasone.

INDICATIONS FOR USE

GCs are used in human and veterinary ECC for a variety of disorders including anaphylaxis, acute lung injury/acute respiratory distress syndrome, septic shock, and spinal cord injury. Evidence for morbidity or mortality benefit with administration of GC within these populations exists; however, data are sparse and often conflicting.

ADVERSE EFFECTS AND CONTRAINDICATIONS

Routine use of GC in some conditions such as trauma, hemorrhagic shock, and traumatic brain injury is likely contraindicated. GC use has been associated with hyperglycemia, pneumonia, urinary tract infection, gastrointestinal ulceration, or increased mortality in some populations.

Adrenal function in cats with cholestatic liver disease

Cats with cholestatic liver disease experience significant morbidity and mortality when they undergo invasive procedures under anesthesia. Although inadequate adrenal response might account for these outcomes, adrenal function in cats with cholestatic liver disease has not been documented, to our knowledge. The goal of our study was to describe adrenal function in these cats. Twenty-seven cats with a serum bilirubin >230 µmol/L (3 mg/dL) and serum alanine aminotransferase >2 times the upper limit of normal had pre– and 60-min post–adrenocorticotropic hormone (ACTH) cortisol analysis after administration of 5 µg/kg cosyntropin intravenously. The change in cortisol concentrations (delta cortisol) was calculated. Pre- and post-ACTH cortisol concentrations were compared to reference values. Pre-ACTH, post-ACTH, and delta cortisol values were compared between cats surviving to discharge or for 30 d postdischarge. Mean pre-ACTH cortisol levels (205 ± 113 nmol/L [7.4 ± 4.2 µg/dL]) and post-ACTH cortisol levels (440 ± 113 nmol/L [15.9 ± 4.1 g/dL]) in cholestatic cats were significantly greater than reference values in clinically normal cats. There was no association of pre- or post-ACTH cortisol with survival. Cats with a delta cortisol <179 nmol/L (6.5 µg/dL) were more likely to be non-survivors at 30 d post-discharge ( p = 0.037) than cats with delta cortisol >179 nmol/L (6.5 µg/dL). Results indicate that cats with cholestasis have high basal and ACTH-stimulated cortisol values. A delta cortisol <179 nmol/L (6.5 µg/dL) defines a population of cats that have decreased 30-d survival.