Evaluation of a low-dose desoxycorticosterone pivalate treatment protocol for long-term management of dogs with primary hypoadrenocorticism

Clinical characteristics, treatment, and outcomes of hypoadrenocorticism in dogs

OBJECTIVES

To determine the long-term survival of dogs with hypoadrenocorticism during the period that desoxycorticosterone pivalate has become widely used. Secondary goals were to compare age at diagnosis, median survival times, and age at death for dogs with hyponatraemic and/or hyperkalaemic hypoadrenocorticism and eunatraemic eukalaemic hypoadrenocorticism, and to determine the frequency of glucocorticoid-related side effects in these dogs.

MATERIALS AND METHODS

Retrospective cohort study with data collected from medical records and from a questionnaire sent to owners of affected dogs.

RESULTS

141 cases were identified; 125 had spontaneous hypoadrenocorticism and 16 had iatrogenic hypoadrenocorticism secondary to treatment of hyperadrenocorticism. Dogs with spontaneous hyponatraemic and/or hyperkalaemic hypoadrenocorticism were significantly younger at the time of diagnosis (median age: 5.1, range: 0.8 to 14.1 years, n = 97) compared to dogs with spontaneous eunatraemic eukalaemic hypoadrenocorticism (median age: 8.3, range: 3.0 to 12.7 years, n = 26). Sixty-six dogs were included in the survival analysis. For dogs with spontaneous hyponatraemic and/or hyperkalaemic hypoadrenocorticism, all of which were managed with desoxycorticosterone pivalate, median survival time was 5.7 years (95% CI: 4.0 to 7.2 years; n = 47) and median age at death was 11.0 years (range: 4.0 to 17.0 years; n = 30). For dogs with spontaneous eunatraemic eukalaemic hypoadrenocorticism, median survival time was 5.6 years (95% CI: 4.1-N/A years; n = 9) and median age at death was 11.8 years (range: 11.0 to 13.0 years; n = 4). The majority of owners that completed the questionnaire reported side effects commonly associated with glucocorticoid therapy.

CLINICAL SIGNIFICANCE

Hypoadrenocorticism carries an excellent prognosis. Desoxycorticosterone pivalate was the most frequently used mineralocorticoid therapy in this group of dogs.

Comparison of prednisolone and alternative glucocorticoid dosing protocols for canine hypoadrenocorticism: insights from a survey-based study

Objectives

The aim of the study was to analyze glucocorticoid (GC) dosing protocols in dogs with hypoadrenocorticism (HA), and to identify predictors for optimal clinical outcomes during both the acute and chronic phases of the disease, as well as during long-term therapy.

Methods

This observational cross-sectional study utilized a case-based online questionnaire. Practicing veterinarians across Germany were invited to participate. The survey collected data in the disease course and follow-ups. Responses were analyzed using descriptive statistics, single and multiple comparisons, and a multivariable logistic regression model.

Results

For 103 dogs the questionnaire was fully completed and analyzed. Of these, 85 dogs (82.5%) were hospitalized, and they received either prednisolone (52.9%), dexamethasone (31.8%) or hydrocortisone (11.8%). Hydrocortisone therapy was associated with a shorter hospitalization time and faster normalization of electrolytes compared to prednisolone. Follow-up data were available for 85 dogs, with 82.35% (n = 70/85) achieving an optimal or well-adjusted clinical outcome. Multivariable logistic regression analysis indicated that the eukalemic and eunatremic form was significantly less associated with the presence of azotemia and the occurrence of an acute adrenal crisis. Dividing the daily GC dosage was associated with poorer clinical outcomes and a reduced likelihood of achieving optimal medication adjustment.

Conclusion

Our findings provide new, relevant recommendations for the therapeutic management of HA in dogs. Hydrocortisone appears to be a promising treatment for managing HA during hospitalization, highlighting its potential use in clinical practice. Once-daily administration of prednisolone is advisable for long-term therapy. To achieve the best possible outcome, implementing an optimal treatment protocol is essential, which veterinarians should tailor based on the needs of both owners and animals. The main limitations of the study include its retrospective nature and the limited number of participants. Future studies, particularly prospective ones, could further validate the beneficial effects of hydrocortisone and evaluate long-term therapy in comparison to prednisolone.

Development of mass spectrometric methods for determination of desoxycorticosterone pivalate and its esterase product in canine serum

Hypoadrenocorticism is a serious condition in dogs that results from autoimmune adrenalitis and depletion of mineralocorticoids and glucocorticoids. Affected dogs respond well to glucocorticoid supplementation and treatment with the synthetic mineralocorticoid desoxycorticosterone pivalate (DOCP). DOCP injected once monthly resolves serum Na/K abnormalities and normalizes water balance, but therapy is expensive. Cost abatement involves prolongation of the 30-day dosage interval or decreasing the 2.2 mg/kg dosage. These approaches are not based on DOCP pharmacokinetics. A full assessment of the practicality of either approach would benefit from understanding drug pharmacokinetics, requiring measurement of DOCP and its esterase product desoxycorticosterone (DOC) in canine serum while avoiding toxic endpoints from overdosing. Mass spectrometric methods were developed including gas chromatography-tandem mass spectrometry of DOCP and DOC-methoxime trimethylsilyl derivatives, an approach sensitive to 2 ng/mL. Greater sensitivity was desired, so liquid chromatography-tandem mass spectrometry (LC-MS/MS) with ESI+ ionization was investigated. Supported liquid extraction was devised for serum with recoveries ∼100%. The LC-MS/MS method was validated for linearity, precision, accuracy and limits of detection (0.029 and 0.019 ng/mL for DOC and DOCP, respectively). A pilot experiment with DOCP-treated hypoadrenocorticism dogs over one-month revealed DOC baseline values as 0.183+/-0.090 ng/mL, which increased to the 1.0 - 2.2 ng/mL range. DOCP was not visible in any samples suggesting 100% conversion. Halving the dosage to 1.1 mg/kg still showed clear increases over the DOC baseline. MS fragmentation involved ring cleavages, dehydrations and double-charged fragments. The methodology was robust and suitable for studying DOC/DOCP pharmacokinetics in future studies of hypoadrenocorticism dogs.

Longitudinal assessment of thyroid function in dogs with hypoadrenocorticism: Clinical outcomes and prevalence of autoantibodies

BACKGROUND

Knowledge about primary hypoadrenocorticism coexisting with immune-mediated thyroiditis (Schmidt's syndrome) in dogs is limited.

OBJECTIVE

To evaluate thyroid function in dogs with naturally occurring hypoadrenocorticism before and during treatment.

ANIMALS

Sixty-six client-owned dogs.

METHODS

Measurement of canine thyroid stimulating hormone (cTSH), total thyroxine (T4), free thyroxine, and autoantibodies against thyroglobulin, T4, and total triiodothyronine.

RESULTS

Thirty-eight dogs were assessed before and 28 during treatment. Follow-up data were available for 24/38 and 17/28 dogs, with median follow-up duration of 3.8 years (range, <1.0-8.8 years) and 4 years (range, 1.1 weeks to 10.5 years), respectively. Canine thyroid stimulating hormone was above the reference range at the time of diagnosis of hypoadrenocorticism in 10 of 38 dogs but decreased into the reference range in 7 for which follow-up data was available. Hypothyroidism was confirmed in 5 dogs at a median age of 11 years (range, 7-15 years). In 4 dogs, the condition was diagnosed after a median treatment duration of 5.75 years (range, 2.6-10 years), while in 1 dog, the diagnosis was made concurrently. One dog had detectable thyroid autoantibodies.

CONCLUSIONS AND CLINICAL RELEVANCE

Hypothyroidism occurs as a rare concurrent condition in dogs with hypoadrenocorticism, potentially at any phase of treatment. Close monitoring of cTSH levels in these dogs could be beneficial, as early changes might indicate the onset of hypothyroidism. The low prevalence of detectable thyroid autoantibodies suggests that nonimmune mechanisms might contribute to thyroid dysfunction.

Clinical findings, treatment, and outcomes in cats with naturally occurring hypoadrenocorticism: 41 cases

BACKGROUND

Hypoadrenocorticism in cats is uncommonly reported. Most reports consist of cats with hyponatremia, hyperkalemia, or both.

HYPOTHESIS/OBJECTIVES

To describe clinical findings, treatment response, and outcome in cats diagnosed with hypoadrenocorticism, including cats with abnormal and normal serum sodium and potassium concentrations.

ANIMALS

Forty-one cats with hypoadrenocorticism; 36 with and 5 without abnormal serum sodium and potassium concentrations.

METHODS

Multicenter retrospective observational study. Data for the entire cohort were assessed using descriptive statistics and differences between cats with and without abnormal serum sodium and potassium concentrations were evaluated.

RESULTS

Median age was 5.7 years (range, 0.2-13.8). Twenty-three (56%) cats were male and 18 (44%) were female. Cats with hyponatremia, hyperkalemia, or both were less likely to have a history of vomiting (P = .01) but more likely to be hypothermic (P = .03), dehydrated (P = .04) or weak (P = .04) on examination, compared with nonhyponatremic and nonhyperkalemic cats. Frequency of hypercalcemia was 31.7%. Exocrine pancreatic insufficiency (EPI) was diagnosed in 4/7 cats tested; all 4 had concurrent cobalamin deficiency. Thirty-five (85.4%) cats survived to discharge. In 2 cats, hypoadrenocorticism occurred secondary to lymphoma. Median survival time (MST) for all-cause mortality was 2035 days (95% confidence interval [CI], 294-4380 days); MST for disease-specific mortality was not reached.

CONCLUSIONS AND CLINICAL IMPORTANCE

Approximately one-third of cats with hypoadrenocorticism had hypercalcemia. In some cases, hyponatremia and hyperkalemia were not observed. Cats with nonneoplastic associated hypoadrenocorticism that survive initial hospitalization can have a favorable long-term prognosis. Testing for EPI may be warranted in cats with hypoadrenocorticism.

A qualitative analysis of the impact of canine hypoadrenocorticism on the quality of life of owners

BACKGROUND

Canine hypoadrenocorticism is a rare chronic disease, which demands intense dog-owner interaction, as its treatment requires to be individualised. The aim of this study was a qualitative analysis of the challenges owners face when dealing with the disease, especially regarding its management and how this affects quality of life. By promoting an online discussion between owners, we transcribed and summarised their experiential knowledge in dealing with the disease.

METHODS

Owners were recruited for the online seminars via social media. After a theoretical introduction, participants were free to share experiences and ask questions. The recorded events were retrospectively analysed.

RESULTS

Twenty-four owners of 22 Addisonian dogs took part in four events. Owners felt most "traumatised" when experiencing their dog's acute adrenal crisis. The initial adjustment phase and distinguishing the non-specific symptoms of hypoadrenocorticism from those of other diseases were also challenging. Overall, owners were well informed on the disease and committed to its long-term adjustment.

CONCLUSIONS

Adrenal crisis and the initial adjustment phase may be more burdening to owners than expected. Understanding what their clients' concerns are, can help veterinarians provide better care and reduce the negative impacts of canine hypoadrenocorticism. Promoting peer to peer support, as well as providing a framework for participative communication might also help.

2023 AAHA Selected Endocrinopathies of Dogs and Cats Guidelines

Canine and feline endocrinopathies reflect an endocrine gland disease or dysfunction with resulting hormonal abnormali ties that can variably affect the patient's wellbeing, quality of life, and life expectancy. These guidelines provide consensus recommendations for diagnosis and treatment of four canine and feline endocrinopathies commonly encountered in clini cal practice: canine hypothyroidism, canine hypercortisolism (Cushing's syndrome), canine hypoadrenocorticism (Addi son's disease), and feline hyperthyroidism. To aid the general practitioner in navigating these common diseases, a stepwise diagnosis and treatment algorithm and relevant background information is provided for managing each of these diseases. The guidelines also describe, in lesser detail, the diagnosis and treatment of three relatively less common endo crinopathies of cats: feline hyperaldosteronism, feline hypothyroidism, and feline hyperadrenocorticism. Additionally, the guidelines present tips on effective veterinary team utilization and client communication when discussing endocrine cases.

Clinical features and long-term management of cats with primary hypoadrenocorticism using desoxycorticosterone pivalate and prednisolone

BACKGROUND

Primary hypoadrenocorticism (PH) is rare in cats and knowledge about treatment is sparse.

OBJECTIVE

To describe cats with PH with a focus on long-term treatment.

ANIMALS

Eleven cats with naturally occurring PH.

METHODS

Descriptive case series with data on signalment, clinicopathological findings, adrenal width, and doses of desoxycorticosterone pivalate (DOCP) and prednisolone during a follow-up period of >12 months.

RESULTS

Cats ranged from 2 to 10 years (median 6.5); 6 cats were British Shorthair. Most common signs were reduced general condition and lethargy, anorexia, dehydration, obstipation, weakness, weight loss, and hypothermia. Adrenal glands on ultrasonography were judged small in 6. Eight cats could be followed for 14 to 70 months (median: 28). Two were started on DOCP doses ≥2.2 mg/kg (2.2; 2.5) and 6 < 2.2 mg/kg (1.5-2.0 mg/kg, median 1.8) q28 days. Both high-dose cats and 4 low-dose cats needed a dose increase. Desoxycorticosterone pivalate and prednisolone doses at the end of the follow-up period were 1.3 to 3.0 mg/kg (median: 2.3) and 0.08 to 0.5 mg/kg/day (median: 0.3), respectively.

CONCLUSIONS AND CLINICAL IMPORTANCE

Desoxycorticosterone pivalate and prednisolone requirements in cats were higher than what is currently used in dogs; thus, a DOCP starting dose of 2.2 mg/kg q28 days and a prednisolone maintenance dose of 0.3 mg/kg/day titrated to the individual need seems warranted. Small adrenal glands (width < 2.7 mm) on ultrasonography in a cat suspected of hypoadrenocorticism can be suggestive of the disease. The apparent predilection of British Shorthaired cats for PH should be further evaluated.

Serum Lipidome Signatures of Dogs with Different Endocrinopathies Associated with Hyperlipidemia

Hyperlipidemia (hypertriglyceridemia, hypercholesterolemia) is a common finding in human and veterinary patients with endocrinopathies (e.g., hypothyroidism and hypercortisolism (Cushing's syndrome; CS)). Despite emerging use of lipidomics technology in medicine, the lipid profiles of these endocrinopathies have not been evaluated and characterized in dogs. The aim of this study was to compare the serum lipidomes of dogs with naturally occurring CS or hypothyroidism with those of healthy dogs. Serum samples from 39 dogs with CS, 45 dogs with hypothyroidism, and 10 healthy beagle dogs were analyzed using a targeted lipidomics approach with liquid chromatography-mass spectrometry. There were significant differences between the lipidomes of dogs with CS, hypothyroidism, and the healthy dogs. The most significant changes were found in the lysophosphatidylcholines, lysophosphatidylethanolamines, lysophosphatidylinositols, phosphatidylcholines, phosphatidylethanolamines, phosphatidylglycerols, ceramides, and sphingosine 1-phosphates. Lipid alterations were especially pronounced in dogs with hypothyroidism. Several changes suggested a more atherogenic lipid profile in dogs with HT than in dogs with CS. In this study, we found so far unknown effects of naturally occurring hypothyroidism and CS on lipid metabolism in dogs. Our findings provide starting points to further examine differences in occurrence of atherosclerotic lesion formation between the two diseases.

Comparison of Hydrocortisone Continuous Rate Infusion and Prednisolone or Dexamethasone Administration for Treatment of Acute Hypoadrenocortical (Addisonian) Crisis in Dogs

Objectives

To determine whether administration of intravenous hydrocortisone is a safe and effective alternative treatment in comparison to the traditional treatment with prednisolone/dexamethasone in dogs presenting with Addisonian crisis; and to assess if there is any advantage of the former over the latter in normalisation of electrolyte imbalances and in hospitalisation length in these dogs.

Methods

Medical records of client-owned dogs with hypoadrenocorticism were retrospectively reviewed. Time until normalisation of sodium and potassium concentration, intravenous fluid needs over the first 24 h and hospitalisation length were compared between hydrocortisone and prednisolone/dexamethasone treated dogs.

Results

Twenty-five dogs met the inclusion criteria; 13 received hydrocortisone and 12 prednisolone/dexamethasone. Intravenous hydrocortisone was well-tolerated but failed to prove superiority in terms of time to normalisation of sodium and potassium concentration. Interestingly, potassium normalised in all dogs prior to discharge, but sodium did not in 1/11 hydrocortisone and 5/9 prednisolone/dexamethasone treated dogs with initial hyponatraemia (p = 0.05). Hydrocortisone treated dogs, however, had more electrolyte re-checks [hydrocortisone treated dogs, median (range): 4 (2–16); prednisolone/dexamethasone treated dogs: 2 (0–6); p = 0.001]. There was no difference in intravenous fluid needs over the first 24 h but hydrocortisone treated dogs had longer hospitalisation [hydrocortisone: 81 (45–309) h; prednisolone/dexamethasone: 52 (22–138) h; p = 0.01].

Clinical Significance

Intravenous hydrocortisone is well-tolerated and safe, but no clear additional benefit over traditional glucocorticoid replacement could be identified. Also, it might result in longer hospitalisation time and more intensive monitoring.

Use of Deoxycorticosterone Pivalate by Veterinarians: A Western European Survey

This study aims to gather knowledge about the use of deoxycorticosterone pivalate (DOCP) by Western European Veterinarians (WEV) in dogs with typical hypoadrenocorticism. An observational cross-sectional study was conducted using an online survey, translated into four languages and disseminated to veterinary affiliates and mailing lists in six countries of Western Continental Europe. Respondents were tasked to share their therapeutic approach to hypoadrenocorticism, whether they preferred DOCP or fludrocortisone and the specific practical use of DOCP. One-hundred and eighty-four responses were included. Of these, 79.9% indicated that they preferred prescribing DOCP over fludrocortisone as a first-line treatment for mineralocorticoid supplementation. A total of 154 respondents had used DOCP at least once. Eighty percent of those who reported their initial dosage prescribed 2.2 mg/kg. After starting DOCP, 68.2% of the respondents assess electrolytes 10 and 25 days after administration following manufacturer instructions. In stable dogs, electrolytes are monitored quarterly, monthly, semi-annually, and annually by 44.2%, 34.4%, 16.9%, and 4.6% of respondents respectively. When treatment adjustment is required, 53% prefer to reduce dosage while 47% increase the interval between doses. Overall, DOCP is the preferred mineralocorticoid supplementation among WEV. Reported variability underlies the need to investigate the best strategies for DOCP use and therapeutic adjustments.

Low-dose desoxycorticosterone pivalate treatment of hypoadrenocorticism in dogs: A randomized controlled clinical trial

Background

Desoxycorticosterone pivalate (DOCP) is a commonly used mineralocorticoid replacement for dogs with primary hypoadrenocorticism (HA), but manufacturer‐recommended dosing protocols can be cost‐prohibitive. Recent reports also have raised concerns that label dose protocols could be excessive.

Objective

To investigate the relative efficacy and adverse effects of 2 DOCP dosages in dogs with primary glucocorticoid and mineralocorticoid deficient HA.

Animals

Thirty‐seven dogs, including 19 test population dogs and 18 controls.

Methods

Randomized controlled double‐blinded clinical trial. Dogs with newly diagnosed primary HA were assigned to standard (2.2 mg/kg q30d, control population) or low‐dose (1.1 mg/kg q30d, test population) DOCP treatment. Clinical and laboratory variables were assessed 10 to 14 days and approximately 30 days after each DOCP treatment for 90 days.

Results

Mean serum sodium to potassium ratios at reevaluations were ≥32 in both populations throughout the study. No dog developed electrolyte abnormalities warranting medical treatment, although hypokalemia occurred on at least 1 occasion in 9 controls and 6 test population dogs. Urine specific gravities (median, interquartile range) were lower in control dogs (1.022, 1.016‐1.029) as compared to test population dogs (1.033, 1.023‐1.039; P = .006). Plasma renin activity was overly suppressed on 84 of 104 (80.8%) assessments in control dogs whereas increased renin activity occurred on 23 of 112 (20.5%) assessments in test population dogs.

Conclusions and Clinical Importance

Low‐dose DOCP protocols appear to be safe and effective for treatment of HA in most dogs. Standard‐dose protocols are more likely to result in biochemical evidence of overtreatment.

Evaluation of symmetric dimethylarginine and creatinine in dogs with primary hypoadrenocorticism receiving long-term mineralocorticoid replacement therapy

OBJECTIVES

To investigate kidney function by determining serum symmetric dimethylarginine (sSDMA) and serum creatinine (sCr) concentrations in dogs with primary hypoadrenocorticism (PH) receiving long-term mineralocorticoid replacement therapy.

METHODS

Dogs with PH receiving a minimum of 12 months of either desoxycorticosterone pivalate or fludrocortisone acetate were included in the study provided that banked frozen serum samples were available for sSDMA analysis. sCr concentrations were retrieved from the medical records. In dogs still alive and presented for regular re-evaluations and in newly diagnosed patients, blood was prospectively collected for sSDMA and sCr determination.

RESULTS

Thirty-two dogs met the inclusion criteria. The treatment time ranged from 12 to 146 months after initial diagnosis (median, 55.5 months). The majority of dogs had normal sSDMA and sCr concentrations throughout the hormone replacement treatment. Both sSDMA and sCr concentrations were persistently elevated in three of 32 dogs. Further workup confirmed chronic kidney disease (CKD) in all three dogs.

CONCLUSIONS

Based on these data, the prevalence of CKD could be higher in dogs with PH receiving long-term mineralocorticoid replacement treatment than in the general dog population. However, additional studies with a larger number of dogs are needed to confirm it.

Evaluation of a low-dose desoxycorticosterone pivalate treatment protocol for long-term management of dogs with primary hypoadrenocorticism

Background

Lowering the dose of desoxycorticosterone pivalate (DOCP) for the treatment of dogs with primary hypoadrenocorticism (PH) decreases costs and could lead to increased owner motivation to treat their affected dogs.

Objective

To evaluate the efficacy of a low‐dose DOCP treatment protocol in dogs with PH.

Animals

Prospective study, 17 client‐owned dogs with naturally occurring PH (12 newly diagnosed, 5 previously treated with fludrocortisone acetate [FC]).

Methods

Dogs with newly diagnosed PH were started on 1.5 mg/kg DOCP SC; dogs previously treated with FC were started on 1.0‐1.8 mg/kg DOCP SC. Reevaluations took place at regular intervals for a minimum of 3 months and included clinical examination and determination of serum sodium and potassium concentrations. The DOCP dosage was adjusted to obtain an injection interval of 28‐30 days and to keep serum electrolyte concentrations within the reference interval.

Results

Median (range) follow‐up was 16.2 months (4.5‐32.3 months). The starting dosage was sufficient in all but 2 dogs and had to be significantly decreased after 2‐3 months to a median dosage (range) of 1.1 mg/kg (0.7‐1.8). Dogs 3 years of age or younger needed significantly higher dosages compared to older dogs. None of them, however, needed the 2.2 mg/kg DOCP dosage, recommended by the manufacturer.

Conclusions and Clinical Importance

A starting dosage of 1.5 mg/kg DOCP is effective in controlling clinical signs and serum electrolyte concentrations in the majority of dogs with PH. An additional dose reduction often is needed to maintain an injection interval of 28‐30 days. Young and growing animals seem to need higher dosages.