Clinical signs and the findings from a physical examination, complete blood count (CBC), serum chemistry profile, and urinalysis
vary depending on the type of deficiency present.
Glucocorticoids are important for maintaining homeostasis, especially during stress. They play a role in metabolizing glucose,
fats, and proteins; stimulating erythropoiesis; and regulating the immune system.1,6 The most common clinical signs of glucocorticoid deficiency include lethargy, weakness, anorexia, weight loss, vomiting,
and diarrhea (Table 1).4,7,11 Other less common clinical signs include polyuria and polydipsia, exercise intolerance, and seizures.7,12 Clinical signs may be intermittent and associated with stressful events such as boarding, grooming, and medical evaluation.
Physical examination findings in dogs with glucocorticoid deficiency are nonspecific and can include weakness and thin body
Table 1: Clinical Signs in Dogs with Glucocorticoid or Glucocorticoid and Mineralocorticoid Deficiency*
Gastrointestinal (GI) signs are common in dogs with glucocorticoid deficiency because glucocorticoids are important for maintaining
GI mucosal health, GI motility, and colonic sodium absorption.1,7,8 Hypocortisolemia may potentiate mucosal ulceration and hemorrhage as a result of decreased vascular integrity.6 Exercise intolerance or seizures may develop if severe hypoglycemia occurs; however, hypoglycemia is typically mild.12
Common findings on a CBC include normocytic, normochromic, nonregenerative anemia and a lack of a stress leukogram (Table 2).7 Glucocorticoids, along with other hormones, stimulate erythropoiesis, so glucocorticoid deficiency may result in anemia.
GI hemorrhage can further contribute to anemia in dogs with hypocortisolemia.6,7,11 A lack of a stress leukogram most commonly manifests as a normal or increased lymphocyte count with or without eosinophilia.5,6
Table 2: Laboratory Findings and Their Proposed Pathogenesis in Dogs with Glucocorticoid Deficiency or Glucocorticoid and
Serum chemistry profile abnormalities in dogs with glucocorticoid deficiency include hypoalbuminemia, hypocholesterolemia,
hypoglycemia, and mild hyponatremia.6,7 Impaired absorption of nutrients, protein-losing enteropathy, and decreased albumin production may contribute to the hypoalbuminemia.13 Hypocholesterolemia is thought to result from altered lipid absorption.6 Hypoglycemia may be due to blunted gluconeogenesis and increased glucose uptake and use by peripheral tissues.6,12 Mild hyponatremia may develop because of decreased vasopressin secretion and blunted colonic sodium absorption. In healthy
dogs, glucocorticoids inhibit vasopressin release; therefore, with glucocorticoid deficiency, inappropriate vasopressin secretion
may cause water retention and result in a dilutional hyponatremia.1,7