I plasma concentrations of adrenocorticotrophic hormone and alpha-melanocyte-stimulating hormone in ferrets (Mustela putorius furo) with hyperadrenocorticism

OBJECTIVE: To determine plasma concentrations of adrenocorticotrophic hormone (ACTH) and alpha-melanocyte stimulating-hormone (alpha-MSH) in healthy ferrets and ferrets with hyperadrenocorticism. ANIMALS: 16 healthy, neutered, privately owned ferrets, 28 healthy laboratory ferrets (21 sexually intact and 7 neutered), and 28 ferrets with hyperadrenocorticism. PROCEDURES: Healthy ferrets were used for determination of reference plasma concentrations of ACTH and a-MSH. Diagnosis of hyperadrenocorticism was made on the basis of history, clinical signs, urinary corticoid-to-creatinine ratios, ultrasonography of the adrenal glands, and macroscopic or microscopic evaluation of the adrenal glands. Blood samples were collected during isoflurane anesthesia. Plasma concentrations of ACTH and alpha-MSH were measured by radioimmunoassay. RESULTS: Plasma concentrations of ACTH in 23 healthy neutered ferrets during the breeding season ranged from 4 to 145 ng/L (median, 50 ng/L). Plasma concentrations of alpha-MSH in 44 healthy neutered or sexually intact ferrets during the breeding season ranged from < 5 to 617 ng/L (median, 37 ng/L). Reference values (the central 95% of the values) for ACTH and alpha-MSH were 13 to 100 ng/L and 8 to 180 ng/L, respectively. Plasma concentrations of ACTH and alpha-MSH in ferrets with hyperadrenocorticism ranged from 1 to 265 ng/L (median, 45 ng/L) and 10 to 148 ng/L (median, 46 ng/L), respectively. These values were not significantly different from those of healthy ferrets. Plasma ACTH concentrations of sexually intact female ferrets in estrus were significantly higher than those of neutered females. CONCLUSIONS AND CLINICAL RELEVANCE: Ferrets with hyperadrenocorticism did not have detectable abnormalities in plasma concentrations of ACTH or alpha-MSH. The findings suggest that hyperadrenocorticism in ferrets is an ACTH and alpha-MSH-independent condition.     

Long-term outcome of domestic ferrets treated surgically for hyperadrenocorticism: 130 cases (1995-2004)

OBJECTIVE: To determine the long-term survival rate and factors that affect survival time of domestic ferrets treated surgically for hyperadrenocorticism. STUDY DESIGN: Retrospective case series. ANIMALS: 130 ferrets with hyperadrenocorticism that were treated surgically. PROCEDURES: Medical records of ferrets surgically treated for hyperadrenocorticism were reviewed. Data recorded included signalment, duration of clinical signs prior to hospital admission, CBC values, serum biochemical analysis results, anesthetic time, surgical time, concurrent diseases, adrenal gland affected (right, left, or both [bilateral]), histopathologic diagnosis, surgical procedure, caudal vena caval involvement (yes or no), postoperative melena (yes or no), days in hospital after surgery, and whether clinical signs of hyperadrenocorticism developed after surgery. RESULTS: 130 ferrets were entered in the study (11 of 130 ferrets were admitted and underwent surgery twice). The 1- and 2-year survival rates were 98% and 88%, respectively. A 50% survival rate was never reached. Combined partial adrenal gland resection with cryosurgery had a significantly negative effect on survival time. No other risk factors were identified. Survival time was not significantly affected by either histopathologic diagnosis or specific affected adrenal gland (right, left, or bilateral). CONCLUSIONS AND CLINICAL RELEVANCE: Ferrets with adrenal gland masses that were treated surgically had a good prognosis. Survival time of ferrets with hyperadrenocorticism undergoing surgery was not affected by the histologic characteristic of the tumor, the adrenal glands affected (right, left, or bilateral), or complete versus partial adrenal gland resection. Debulking was a sufficient surgical technique to allow a favorable long-term outcome when complete excision was not possible.     

Urinary glucocorticoid excretion in the diagnosis of hyperadrenocorticism in ferrets

Hyperadrenocorticism in ferrets is usually associated with unaltered plasma concentrations of cortisol and adrenocorticotropic hormone (ACTH), although the urinary corticoid/creatinine ratio (UCCR) is commonly elevated. In this study the urinary glucocorticoid excretion was investigated in healthy ferrets and in ferrets with hyperadrenocorticism under different circumstances. In healthy ferrets and in one ferret with hyperadrenocorticism, approximately 10% of plasma cortisol and its metabolites was excreted in the urine. High-performance liquid chromatography (HPLC) revealed one third of the urinary corticoids to be unconjugated cortisol; the other peaks mainly represented cortisol conjugates and metabolites. In 21 healthy sexually intact ferrets, the UCCR started to increase by the end of March and declined to initial values halfway the breeding season (June). In healthy neutered ferrets there was no significant seasonal influence on the UCCR. In two neutered ferrets with hyperadrenocorticism the UCCR was increased, primarily during the breeding season. In 27 of 31 privately owned ferrets with hyperadrenocorticism, the UCCR was higher than the upper limit of the reference range (2.1 x 10(-6)). In 12 of 14 healthy neutered ferrets dexamethasone administration decreased the UCCR by more than 50%, whereas in only 1 of the 28 hyperadrenocorticoid ferrets did the UCCR decrease by more than 50%. We conclude that the UCCR in ferrets primarily reflects cortisol excretion. In healthy sexually intact ferrets and in ferrets with hyperadrenocorticism the UCCR increases during the breeding season. The increased UCCR in hyperadrenocorticoid ferrets is resistant to suppression by dexamethasone, indicating ACTH-independent cortisol production.     

Correlation between age at neutering and age at onset of hyperadrenocorticism in ferrets

OBJECTIVE: To determine prevalence of hyperadrenocorticism in ferrets in The Netherlands and evaluate age, sex, and age at neutering in affected ferrets. DESIGN: Prevalence survey and retrospective study. ANIMALS: 50 ferrets with hyperadrenocorticism and 1,267 ferrets without hyperadrenocorticism. PROCEDURE: A questionnaire was sent to 1,400 members of a ferret-owners organization in The Netherlands; 492 (35%) owners returned the questionnaire, providing usable data on 1,274 ferrets. Seven of these ferrets developed hyperadrenocorticism during the survey period; medical records for these ferrets and 43 ferrets with confirmed hyperadrenocorticism were reviewed. Hyperadrenocorticism was confirmed by histologic examination of an excised adrenal gland (92% of ferrets) or clinical improvement after excision. RESULTS: Prevalence of hyperadrenocorticism in the survey population was 0.55%. Sex was not associated with prevalence of disease. Median time interval between neutering and diagnosis of hyperadrenocorticism was 3.5 years. A significant linear correlation between age at neutering and age at time of diagnosis was detected. CONCLUSIONS AND CLINICAL RELEVANCE: Age at neutering may be associated with age at development of hyperadrenocorticism in ferrets.     

Ultrasonographic Characteristics of the Adrenal Glands in Dogs With Pituitary-Dependent Hyperadrenocorticism: Comparison With Normal Dogs

Ultrasonographic evaluation of the adrenal glands was performed in 10 dogs with pituitary-dependent hyperadrenocorticism (PDH) and in 10 age- and weight-matched healthy control dogs. Thickness, shape, and echogenicity were determined for each adrenal gland. Adrenal thickness in dogs with PDH (median, 10 mm-left; 8.5 mm-right) was significantly greater than thickness in control dogs (median, 6 mm-left; 6 mm-right). Other ultrasonographic characteristics associated with PDH included bilaterally symmetrical adrenomegaly and maintenance of normal adrenal shape. Adrenal echogenicity was homogeneous and less than that of the adjacent renal cortex in 8 of 10 dogs with PDH and in 10 of 10 control dogs. Heterogenous echogenicity was present in 2 of 10 dogs with PDH, and was associated with nodular cortical hyperplasia in one of those dogs. Results of this study confirm the difference in sonographic appearance between PDH-induced bilateral cortical hyperplasia and functional adrenocortical neoplasia, and show a difference in so-nographically determined adrenal size between healthy dogs and dogs with PDH. J Vet Intern Med 1996; 10:110–115. Copyright © 1996 by the American College of Veterinary Internal Medicine .     

RETROSPECTIVE REVIEW OF THE ULTRASONOGRAPHIC FEATURES OF ADRENAL LESIONS IN 21 FERRETS

Clinical signs and follow-up information were recorded. Histopathologic diagnoses were obtained for 25 adrenal glands in 21 ferrets. Adrenal lesions included ten adenocarcinomas, nine adenomas, one hyperplasia and one cortical cyst. Four adrenal glands (all right-sided) were diagnosed as unspecified adrenal tumors but lacked a definite histopathologic diagnosis (adenoma vs. adenocarcinoma) due to incomplete surgical resection and consequent small sample sizes. Bilateral adrenal lesions were identified in 4 ferrets (19%). Adrenal shape, size, echogenicity, laterality, and the presence of vascular invasion were evaluated with ultrasound. Size and shape were variable and not specific to lesion type. Both benign and malignant adrenal tumors (adenomas, adenocarcinomas) appeared most often as masses with increased thickness and a normal length (11/23), less frequently as larger masses with increased thickness and length (4/23) or as nodules focally deforming the normal adrenal shape (6/23). The only cortical cyst appeared as a nodule. Three adrenal glands had a normal size and shape and were diagnosed as adenomas (2) or hyperplasia (1). Therefore treatment may be warranted based solely on clinical signs if adrenal glands are ultrasonographically normal. Vascular invasion was not identified ultrasonographically. However, focal absence of periglandular fat resulting in contact of 8 adrenal glands with either caudal vena cava (6), aorta (1) or liver (1) identified ultrasonographically, correlated with incomplete surgical resectability (6/8) and histopathologic diagnoses of carcinoma (4/8) or unspecified tumors (4/8). Therefore, a focal absence of periglandular fat between the adrenal gland and the large vessels or liver, deviation or compression of the large vessels by the adrenal lesion may indicate malignancy. Adrenal tumors (benign and malignant) were often associated with a prominent uterus, uterine stump or prostate with or without prostatic cysts.     

CHANGES IN ULTRASONOGRAPHIC APPEARANCE OF ADRENAL GLANDS IN DOGS WITH PITUITARY-DEPENDENT HYPERADRENOCORTICISM TREATED WITH TRILOSTANE

Trilostane, a 3beta-hydroxysteroid dehydrogenase inhibitor, has been used successfully over the last few years for the treatment of canine pituitary-dependent hyperadrenocorticism. In a prospective study of 19 dogs with pituitary-dependent hyperadrenocorticism, the adrenal glands were measured before and at least 6 months after initiation of trilostane therapy. Right adrenal gland length and caudal pole thickness and left adrenal gland caudal pole thickness increased significantly (p < or = 0.05); there was no significant change in left adrenal gland length. Enlargement of adrenal glands during trilostane therapy may occur as a result of suppression of the negative feedback mechanism affecting cortisol production.     

Surgical treatment and long-term outcome of ferrets with bilateral adrenal tumors or adrenal hyperplasia: 56 cases (1994-1997).

OBJECTIVE: To determine signalment, clinical signs, concurrent diseases, response to surgical treatment, and long-term outcome of ferrets with bilateral adrenal tumors or adrenal hyperplasia. DESIGN: Retrospective study. ANIMALS: 56 ferrets with bilateral adrenal tumors or adrenal hyperplasia confirmed histologically following subtotal bilateral adrenalectomy. PROCEDURE: Medical records of all ferrets with bilateral adrenal tumors or hyperplasia examined between 1994 and 1997 were reviewed. Ferrets underwent a subtotal bilateral adrenalectomy or a unilateral adrenalectomy initially, followed by a unilateral subtotal adrenalectomy when tumors or hyperplasia later developed on the contralateral adrenal gland. A long-term follow-up of a minimum of 18 months after final adrenal gland surgery was obtained by examination of medical records and follow-up telephone conversations. RESULTS: Clinical signs of hyperadrenocorticism included bilaterally symmetric alopecia, return to male sexual behavior in castrated male ferrets, or swollen vulva in spayed female ferrets. Surgical treatment of bilateral adrenal disease by subtotal bilateral adrenalectomy (or unilateral adrenalectomy followed by contralateral unilateral subtotal adrenalectomy) was effective with a mortality rate of < 2%. Only 3 (5%) ferrets required glucocorticoid or mineralocorticoid replacement following subtotal bilateral adrenalectomy. Recurrence after bilateral adrenalectomy was 15% with a mean long-term follow-up period of 30 months. CONCLUSIONS AND CLINICAL RELEVANCE: Bilaterally symmetric alopecia, return to male sexual behavior in castrated male ferrets, or swollen vulva in spayed female ferrets are indicative of adrenal tumors or adrenal hyperplasia in ferrets. Surgical treatment of bilateral adrenal disease by subtotal bilateral adrenalectomy is effective, with a low rate of complications and postoperative recurrence rate.     

Effects of melatonin administration on the clinical course of adrenocortical disease in domestic ferrets

OBJECTIVE: To evaluate the effect of oral administration of melatonin on clinical signs, tumor size, and serum steroid hormone concentrations in ferrets with adrenocortical disease. DESIGN: Noncontrolled clinical trial. ANIMALS: 10 adult ferrets with clinical signs of adrenocortical disease (confirmed via serum steroid hormone concentration assessments). PROCEDURES: Melatonin (0.5 mg) was administered orally to ferrets once daily for 1 year. At 4-month intervals, a complete physical examination; abdominal ultrasonographic examination (including adrenal gland measurement); CBC; serum biochemical analyses; and assessment of serum estradiol, androstenedione, and 17alpha-hydroxyprogesterone concentrations were performed. Serum prolactin and dehydroepiandrosterone sulfate concentrations were evaluated at the first, second, and last examinations, and serum cortisol concentration was evaluated at the first and last examinations. RESULTS: Daily oral administration of melatonin greatly affected clinical signs of adrenocortical disease in ferrets; changes included hair regrowth, decreased pruritus, increased activity level and appetite, and decreased vulva or prostate size. Mean width of the abnormally large adrenal glands was significantly increased after the 12-month treatment period. Recurrence of clinical signs was detected in 6 ferrets at the 8-month evaluation. Compared with pretreatment values, serum 17alpha-hydroxyprogesterone and prolactin concentrations were significantly increased and decreased after 12 months, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that melatonin is a useful, easily administered, palliative treatment to decrease clinical signs associated with adrenocortical disease in ferrets, and positive effects of daily treatment were evident for at least an 8-month period. Oral administration of melatonin did not decrease adrenal gland tumor growth in treated ferrets.     

ULTRASONOGRAPHIC PARAMETERS OF NORMAL CANINE ADRENAL GLANDS: COMPARISON TO NECROPSY FINDINGS

Ultrasonographic evaluation of the adrenal glands was performed in 14 fasted healthy adult dogs. Frequency of visualization was 100% for both the left and right adrenal glands. Moderate correlation was present between Ultrasonographic and gross measurements of thickness for both left (r_s= 0.727; p < .005) and right (r_s= 0.537; p < .05) adrenal glands. However, no correlation was found between Ultrasonographic and gross measurements for length or width of either adrenal gland. Differentiation of adrenal cortex and medulla was possible in 79% of left adrenal glands and 64% of right adrenal glands. The echogenicity of the adrenal glands was less than that of the renal cortex in all dogs. Factors which made evaluation of the adrenal glands more difficult included pyloric gas, intestinal gas, and deep-chested body conformation.     

Clinical and endocrine responses to treatment with deslorelin acetate implants in ferrets with adrenocortical disease

OBJECTIVE: To evaluate the clinical and endocrine responses of ferrets with adrenocortical disease (ACD) to treatment with a slow-release implant of deslorelin acetate. ANIMALS: 15 ferrets with ACD. PROCEDURE: Ferrets were treated SC with a single slow-release, 3-mg implant of deslorelin acetate. Plasma estradiol, androstenedione, and 17-hydroxyprogesterone concentrations were measured before and after treatment and at relapse of clinical signs; at that time, the adrenal glands were grossly or ultrasonographically measured and affected glands that were surgically removed were examined histologically. RESULTS: Compared with findings before deslorelin treatment, vulvar swelling, pruritus, sexual behaviors, and aggression were significantly decreased or eliminated within 14 days of implantation; hair regrowth was evident 4 to 6 weeks after treatment. Within 1 month of treatment, plasma hormone concentrations significantly decreased and remained decreased until clinical relapse. Mean time to recurrence of clinical signs was 13.7 +/- 3.5 months (range, 8.5 to 20.5 months). In 5 ferrets, large palpable tumors developed within 2 months of clinical relapse; 3 of these ferrets were euthanatized because of adrenal gland tumor metastasis to the liver or tumor necrosis. CONCLUSIONS AND CLINICAL RELEVANCE: In ferrets with ACD, a slow-release deslorelin implant appears promising as a treatment to temporarily eliminate clinical signs and decrease plasma steroid hormone concentrations. Deslorelin may not decrease adrenal tumor growth in some treated ferrets. Deslorelin implants may be useful in the long-term management of hormone-induced sequelae in ferrets with ACD and in treatment of animals that are considered at surgical or anesthetic risk.     

Trabecular bone morphometry in beagles with hyperadrenocorticism and adrenal adenomas

Trabecular bone morphometry was done on rib samples of beagles with hyperadrenocorticism and adrenal adenomas to evaluate bone loss and the remodeling changes responsible. Beagles diagnosed as having clinical hyperadrenocorticism and those with milder or subclinical hyperadrenocorticism diagnosed on the basis of adrenal and pituitary lesions at necropsy had increased adrenal and pituitary gland weights. In a group of dogs with adrenal cortical adenomas there was atrophy of remaining cortex, and the combined weight of adrenal glands or pituitary weights were not increased. In dogs with clinical hyperadrenocorticism, mean trabecular bone volume was 25% less than controls (P = 0.10). In both clinical and subclinical hyperadrenocorticism groups, the extent of trabecular surface with unmineralized osteoid matrix and osteoblasts was significantly reduced. There were no changes in resorption surfaces or number of osteoclasts present. No bone changes were seen in dogs with adrenal adenomas. In dogs with hyperadrenocorticism it appeared that decreased bone formation was primarily responsible for the relative osteopenia that developed. Although parathyroid glands were moderately enlarged in those dogs for which weights were available, the bone changes were not those of increased remodeling expected in hyperparathyroidism.     

Evaluation of canine hyperadrenocorticism, using computed tomography

Abdominal computed tomography was performed in 9 dogs with hyperadrenocorticism and in 2 healthy dogs. Both adrenal glands were identified in all dogs. Computed tomography allowed accurate identification of the sites of adrenal gland dysfunction, when interpreted in combination with a biochemical diagnosis of canine hyperadrenocorticism. This accuracy permitted the retroperitoneal approach to be used for all adrenalectomies. Use of contrast medium (although not essential) was helpful in the computed tomographic identification of blood vessels, kidneys, and other abdominal organs.     

Ultrasonography Criteria for Differentiating ACTH Dependency from ACTH Independency in 47 Dogs with Hyperadrenocorticism and Equivocal Adrenal Asymmetry

Background: Adrenal ultrasonography (US) in dogs with hyperadrenocorticism (HAC) is commonly used to distinguish adrenocorticotropic hormone (ACTH)‐independent (AIHAC) and ACTH‐dependent hyperadrenocorticism (ADHAC). To date, no cut‐off values for defining adrenal atrophy in cases of adrenal asymmetry have been determined. Given that asymmetrical hyperplasia is sometimes observed in ADHAC, adrenal asymmetry without ultrasonographic proof of adrenocortical tumor such as vascular invasion or metastasis can be equivocal. Objective: The purpose of this study was to compare adrenal US findings between cases of ADHAC and AIHAC in dogs with equivocal adrenal asymmetry (EAA), and to identify useful criteria for their distinction. Animals: Forty dogs with EAA were included. Methods: Ultrasound reports of HAC dogs with adrenal asymmetry without obvious vascular invasion or metastases were reviewed. Dogs were classified as cases of ADHAC (n = 28) or AIHAC (n = 19), determined by plasma ACTH concentration. The thickness, shape, and echogenicity of both adrenal glands and presence of adjacent vascular compression were compared between AIHAC and ADHAC groups. Results: The maximal dorsoventral thickness of the smaller gland (SDV) ranged from 2.0 to 5.0 mm in AIHAC and from 5.0 to 15.0 mm in ADHAC. The 95% confidence intervals for estimated sensitivity and specificity of a SDV cut‐off set at 5.0 mm in the diagnosis of AIHAC were 82–100 and 82–99%, respectively. Other tested US criteria were found to overlap extensively between the 2 groups, precluding their usefulness for distinction. Conclusion and Clinical Importance: In EAA cases, an SDV ≤5.0 mm is an appropriate cut‐off for AIHAC ultrasonographic diagnosis.     

Ultrasonographic measurements of adrenal glands in cats with hyperthyroidism

Feline hyperthyroidism is potentially associated with exaggerated responsiveness of the adrenal gland cortex. The adrenal glands of 23 hyperthyroid cats were examined ultrasonographically and compared to the adrenal glands of 30 control cats. Ten hyperthyroid cats had received antithyroid drugs until 2 weeks before sonography, the other 13 were untreated. There was no difference in adrenal gland shape between healthy and hyperthyroid cats: bean-shaped, well-defined, hypoechoic structures surrounded by a hyperechoic halo in 43/60 (71.6%) healthy cats and 34/46 (73.9%) hyperthyroid cats; more ovoid in 13/60 (21.6%) healthy cats and 9/46 (19.6%) hyperthyroid cats while more elongated in 4/60 (6.7%) healthy cats, 3/46 (6.5%) hyperthyroid cats. Hyperechoic foci were present in 9/23 (39.1%) hyperthyroid cats and 2/30 (6.7%) healthy cats. The adrenal glands were significantly larger in hyperthyroid cats, although there was overlap in size range. The mean difference between hyperthyroid cats and healthy cats was 1.6 and 1.7 mm in left and right adrenal gland length, 0.8 and 0.9 mm in left and right cranial adrenal gland height, and 0.4 and 0.9 mm in left and right caudal adrenal gland height. There was no significant difference between the adrenal gland measurements in treated and untreated hyperthyroid cats. The adrenomegaly was most likely associated with the hypersecretion of the adrenal cortex documented in hyperthyroid cats. Hyperthyroidism should be an alternative to hyperadrenocorticism, hyperaldosteronism, and acromegaly in cats with bilateral moderate adrenomegaly.     

Adrenal gland disease in ferrets.

Adrenal gland disease in ferrets is unique to this species, with clinical signs and pathophysiology different from those seen in the dog. Its prevalence is increasing; 70% of pet ferrets in the United States were affected in 2003. The exact causes of the adrenal gland changes that lead to the disease are not known. Early oophorohysterectomies and neutering, combined with the artificially prolonged photoperiod experienced by indoor pet ferrets, and a possible genetic component, may be contributing factors. Signs of adrenal gland disease include progressive hair loss, pruritis, lethargy, atrophy, and, in female ferrets, vulvar swelling. An understanding of the signs and physiologic changes is necessary for diagnosis and treatment. A review of anatomy, physiology, and current surgical and medical options is presented.     

Cytochrome b5 expression in gonadectomy-induced adrenocortical neoplasms of the domestic ferret (Mustela putorius furo)

Whereas the adrenal glands of healthy ferrets produce only limited amounts of androgenic steroids, adrenocortical neoplasms that arise in neutered ferrets typically secrete androgens or their derivative, estrogen. The 17,20-lyase activity of cytochrome P450 17alpha-hydroxylase/17,20-lyase (P450c17) must increase to permit androgen biosynthesis in neoplastic adrenal tissue. We screened ferret adrenocortical tumor specimens for expression of cytochrome b(5) (cyt b(5)), an allosteric regulator that selectively enhances the 17,20-lyase activity of P450c17. Cyt b(5) immunoreactivity was evident in 24 of 25 (96%) adrenocortical adenomas/carcinomas from ferrets with signs of ectopic sex steroid production. Normal adrenocortical cells lacked cyt b(5), which may account for the low production of adrenal androgens in healthy ferrets. Other markers characteristic of gonadal somatic cells, such as luteinizing hormone receptor, aromatase, and GATA4, were coexpressed with cyt b(5) in some of the tumors. We concluded that cyt b(5) is upregulated during gonadectomy-induced adrenocortical neoplasia and is a marker of androgen synthetic potential in these tumors.     

Intramuscular administration of a low dose of ACTH for ACTH stimulation testing in dogs

OBJECTIVE: To compare adrenal gland stimulation achieved following administration of cosyntropin (5 microg/kg [2.3 microg/lb]) IM versus IV in healthy dogs and dogs with hyperadrenocorticism. DESIGN: Clinical trial. Animals-9 healthy dogs and 9 dogs with hyperadrenocorticism. PROCEDURES: In both groups, ACTH stimulation was performed twice. Healthy dogs were randomly assigned to receive cosyntropin IM or IV first, but all dogs with hyperadrenocorticism received cosyntropin IV first. In healthy dogs, serum cortisol concentration was measured before (baseline) and 30, 60, 90, and 120 minutes after cosyntropin administration. In dogs with hyperadrenocorticism, serum cortisol concentration was measured before and 60 minutes after cosyntropin administration. RESULTS: In the healthy dogs, serum cortisol concentration increased significantly after administration of cosyntropin, regardless of route of administration, and serum cortisol concentrations after IM administration were not significantly different from concentrations after IV administration. For both routes of administration, serum cortisol concentration peaked 60 or 90 minutes after cosyntropin administration. In dogs with hyperadrenocorticism, serum cortisol concentration was significantly increased 60 minutes after cosyntropin administration, compared with baseline concentration, and concentrations after IM administration were not significantly different from concentrations after IV administration. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that in healthy dogs and dogs with hyperadrenocorticism, administration of cosyntropin at a dose of 5 microg/kg, IV or IM, resulted in equivalent adrenal gland stimulation.     

Leuprolide acetate treatment of adrenocortical disease in ferrets

OBJECTIVE: To determine the effects of leuprolide acetate, a long-acting gonadotropin-releasing hormone analog, in ferrets with adrenocortical diseases. DESIGN: Case series. ANIMALS: 20 ferrets with adrenocortical disease diagnosed on the basis of clinical signs and plasma sex hormone concentrations. PROCEDURE: Ferrets were treated with leuprolide (100 microg, IM, once), and plasma hormone concentrations were measured before and 3 to 6 weeks after treatment. RESULTS: Leuprolide treatment resulted in significant reductions in plasma estradiol, 17 alpha-hydroxyprogesterone, androstenedione, and dehydroepiandrosterone concentrations and eliminated or reduced clinical signs associated with adrenocortical disease. Decreases in vulvar swelling, pruritus, and undesirable sexual behaviors and aggression were evident 14 days after treatment; hair regrowth was evident by 4 weeks after treatment. The response to treatment was transitory, and clinical signs recurred in all ferrets. Mean +/- SEM time to recurrence was 3.7 +/- 0.4 months (range, 1.5 to 8 months). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that leuprolide can be safely used to temporarily eliminate clinical signs and reduce sex hormone concentrations in ferrets with adrenocortical diseases. However, the safety of long-term leuprolide use in ferrets has not been investigated, and the long-term effects of leuprolide in ferrets with nodular adrenal gland hyperplasia or adrenal gland tumors are unknown.     

Ultrasonographic characteristics of both adrenal glands in 15 dogs with functional adrenocortical tumors.

Ultrasonographic examination of both adrenal glands was performed in 15 dogs with functional adrenocortical tumors (FAT). Bilateral adrenal tumors were diagnosed in three of 15 dogs, and unilateral tumors were diagnosed in 12 of 15 dogs. Adrenal tumors were characterized by adrenal gland enlargement with loss of the normal shape and parenchymal structure. The contralateral adrenal gland could be imaged in all dogs with unilateral tumors. Based on size, shape, and parenchymal structure, the contralateral adrenal gland was similar to adrenal glands of normal dogs. The results of this study show that: 1) both adrenal glands should be imaged routinely in dogs with hyperadrenocorticism; 2) bilateral adrenocortical tumors seem to be more frequent than previously assumed; 3) one normal adrenal gland does not exclude the existence of a contralateral FAT; and 4) the functional atrophy of the contralateral adrenal gland in dogs with FAT may not be apparent ultrasonographically.