Hypoadrenocorticism in dogs, or, as it is known in people,
Addison's disease
Addison's disease, also known as primary adrenal insufficiency, is a rare long-term endocrine disorder characterized by inadequate production of the steroid hormones cortisol and aldosterone by the two outer layers of the cells of the adrenal ...
, is an
endocrine system
The endocrine system is a messenger system comprising feedback loops of the hormones released by internal glands of an organism directly into the circulatory system, regulating distant target organs. In vertebrates, the hypothalamus is the neu ...
disorder that occurs when the
adrenal gland
The adrenal glands (also known as suprarenal glands) are endocrine glands that produce a variety of hormones including adrenaline and the steroids aldosterone and cortisol. They are found above the kidneys. Each gland has an outer cortex which ...
s fail to produce enough
hormone
A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are required ...
s for normal function. The adrenal glands secrete
glucocorticoid
Glucocorticoids (or, less commonly, glucocorticosteroids) are a class of corticosteroids, which are a class of steroid hormones. Glucocorticoids are corticosteroids that bind to the glucocorticoid receptor that is present in almost every vertebr ...
s such as
cortisol
Cortisol is a steroid hormone, in the glucocorticoid class of hormones. When used as a medication, it is known as hydrocortisone.
It is produced in many animals, mainly by the ''zona fasciculata'' of the adrenal cortex in the adrenal gland ...
and
mineralocorticoid
Mineralocorticoids are a class of corticosteroids, which in turn are a class of steroid hormones. Mineralocorticoids are produced in the adrenal cortex and influence salt and water balances (electrolyte balance and fluid balance). The primary mi ...
s such as
aldosterone
Aldosterone is the main mineralocorticoid steroid hormone produced by the zona glomerulosa of the adrenal cortex in the adrenal gland. It is essential for sodium conservation in the kidney, salivary glands, sweat glands, and colon. It plays a c ...
; when proper amounts of these are not produced, the metabolic and
electrolyte
An electrolyte is a medium containing ions that is electrically conducting through the movement of those ions, but not conducting electrons. This includes most soluble salts, acids, and bases dissolved in a polar solvent, such as water. Upon dis ...
balance is upset.
Mineralocorticoids control the amount of
potassium
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosphe ...
, sodium, and water in the body.
[ (]PDF
Portable Document Format (PDF), standardized as ISO 32000, is a file format developed by Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems. ...
) Hypoadrenocorticism is fatal if left untreated.
The most common cause of inadequate adrenal production is idiopathic adrenocortical atrophy. All causes for hypoadrenocorticism are not yet known. The usual causes are genetic, often related to autoimmune
In immunology, autoimmunity is the system of immune responses of an organism against its own healthy cells, tissues and other normal body constituents. Any disease resulting from this type of immune response is termed an "autoimmune disease". P ...
disorders, where the body attacks and kill its own tissue ("immune mediated destruction"). Other cases are caused by various disease processes,[ including failure of the pituitary gland to secrete ]ACTH
Adrenocorticotropic hormone (ACTH; also adrenocorticotropin, corticotropin) is a polypeptide tropic hormone produced by and secreted by the anterior pituitary gland. It is also used as a medication and diagnostic agent. ACTH is an important co ...
, the hormone which stimulates the adrenal production of cortisol.
Hypoadrenocorticism is more frequent in dogs than in humans; in fact, it may occur one hundred times more often in the canine population. It mostly affects young to middle-aged female dogs,[ as the average age at diagnosis being four years old (although it has been found in puppies and dogs up to twelve years old). About seventy percent of dogs that are diagnosed with hypoadrenocorticism are female.][ Hypoadrenocorticism is still relatively uncommon or underdiagnosed in dogs. Statistics gathered from a large veterinary hospital placed the number at 0.36 dogs per 1000. For an average veterinary practice with two veterinarians and 1500 canine patients, this would mean an average of one diagnosis of the disease each year.][(]PDF
Portable Document Format (PDF), standardized as ISO 32000, is a file format developed by Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems. ...
)
Signs and symptoms
The most common clinical manifestations are related to mental status and gastrointestinal function; they include lethargy, anorexia, vomiting, weight loss, and weakness. Additional findings may include dehydration, bradycardia, weak femoral pulses, abdominal pain
Abdominal pain, also known as a stomach ache, is a symptom
Signs and symptoms are the observed or detectable signs, and experienced symptoms of an illness, injury, or condition. A sign for example may be a higher or lower temperature than ...
, lack of appetite, tremors or shaking, muscle weakness, low body temperature, collapse, and pain in the hindquarters. Polyuria and polydipsia, diarrhea, and shivering are occasionally reported.
Hypoglycemia
Hypoglycemia, also called low blood sugar, is a fall in blood sugar to levels below normal, typically below 70 mg/dL (3.9 mmol/L). Whipple's triad is used to properly identify hypoglycemic episodes. It is defined as blood glucose belo ...
can also be present, and initially may be confused with a seizure disorder or an insulin-secreting pancreatic tumor (insulinoma
An insulinoma is a tumour of the pancreas that is derived from beta cells and secretes insulin. It is a rare form of a neuroendocrine tumour. Most insulinomas are benign in that they grow exclusively at their origin within the pancreas, but a min ...
). Hypoadrenocorticism may also be misdiagnosed as food poisoning, parvovirus enteritis
Enteritis is inflammation of the small intestine. It is most commonly caused by food or drink contaminated with pathogenic microbes,Dugdale, David C., IIII, and George F Longretc"Enteritis" MedlinePlus Medical Encyclopedia, 18 October 2008. Access ...
, gastric volvulus
Gastric volvulus or volvulus of stomach is a twisting of all or part of the stomach by more than 180 degrees with obstruction of the flow of material through the stomach, variable loss of blood supply and possible tissue death. The twisting can oc ...
, or spinal/joint problems, earning this disease nicknames like "the Great Mimic" and "the Great Imitator".[ It is possible not to see any signs of the disease until 90% of the adrenal cortex is no longer functioning.][
]
Addisonian crisis
If hyponatremia (low sodium) and hyperkalemia (high potassium) are severe, the resulting hypovolemia, prerenal azotemia, and cardiac arrhythmia
Arrhythmias, also known as cardiac arrhythmias, heart arrhythmias, or dysrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. A resting heart rate that is too fast – above 100 beats per minute in adults ...
s may result in an Addisonian crisis. In severe cases, the patient may be presented in shock and moribund. Addisonian crisis must be differentiated from other life-threatening disorders such as diabetic ketoacidosis
Diabetic ketoacidosis (DKA) is a potentially life-threatening complication of diabetes mellitus. Signs and symptoms may include vomiting, abdominal pain, deep gasping breathing, increased urination, weakness, confusion and occasionally loss of ...
, necrotizing pancreatitis, and septic peritonitis.
Causes
The adrenal glands are located above the kidney
The kidneys are two reddish-brown bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; blood ...
s. The adrenal outer layer, or cortex, has three layers; each produces a specific type of steroid.[
]
Primary
Primary adrenocortical insufficiency
Adrenal insufficiency is a condition in which the adrenal glands do not produce adequate amounts of steroid hormones. The adrenal gland normally secretes glucocorticoids (primarily cortisol), mineralocorticoids (primarily aldosterone), and andro ...
is the more common form of hypoadrenocorticism. All layers of the adrenal gland stop functioning; the problem is with the adrenal gland.[ This causes a deficiency of both mineralocorticoid and glucocorticoid secretion. Most cases are classified as idiopathic, although immune-mediated adrenocortical destruction is a likely cause. Bilateral destruction of the ]adrenal cortex
The adrenal cortex is the outer region and also the largest part of an adrenal gland. It is divided into three separate zones: zona glomerulosa, zona fasciculata and zona reticularis. Each zone is responsible for producing specific hormones. It is ...
by neoplasia (e.g. lymphosarcoma), granulomatous disease, or arterial thrombosis
Thrombosis (from Ancient Greek "clotting") is the formation of a blood clot inside a blood vessel, obstructing the flow of blood through the circulatory system. When a blood vessel (a vein or an artery) is injured, the body uses platelets (thr ...
can also cause primary adrenocortical insufficiency. The destruction is progressive, although variable in rate, ultimately leading to complete loss of adrenocorotical function. A partial deficiency syndrome may occur initially, with signs manifested only during times of stress
Stress may refer to:
Science and medicine
* Stress (biology), an organism's response to a stressor such as an environmental condition
* Stress (linguistics), relative emphasis or prominence given to a syllable in a word, or to a word in a phrase ...
(e.g., boarding, travel, surgery).
Secondary
In secondary hypoadrenocorticism the problem is not in the adrenal gland but in the pituitary gland
In vertebrate anatomy, the pituitary gland, or hypophysis, is an endocrine gland, about the size of a chickpea and weighing, on average, in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain. The ...
. Usually, the anterior portion of the pituitary gland produces a hormone, adrenocorticotropic hormone
Adrenocorticotropic hormone (ACTH; also adrenocorticotropin, corticotropin) is a polypeptide tropic hormone produced by and secreted by the anterior pituitary gland. It is also used as a medication and diagnostic agent. ACTH is an important c ...
(ACTH), that signals the zona fasciculata
The ''zona fasciculata'' (sometimes, fascicular or fasciculate zone) constitutes the middle and also the widest zone of the adrenal cortex, sitting directly beneath the ''zona glomerulosa''. Constituent cells are organized into bundles or "fascicl ...
and zona reticularis
The zona reticularis (sometimes, reticulate zone) is the innermost layer of the adrenal cortex, lying deep to the zona fasciculata and superficial to the adrenal medulla. The cells are arranged cords that project in different directions giving a n ...
to produce their steroids. When the pituitary is unable to produce ACTH, these zones stop production of their hormones. The zona glomerulosa
The ''zona glomerulosa'' (sometimes, glomerular zone) of the adrenal gland is the most superficial layer of the adrenal cortex, lying directly beneath the renal capsule. Its cells are ovoid and arranged in clusters or arches (''glomus'' is Latin ...
is not controlled by ACTH, and remains able to produce a normal amount of mineralocorticoids.[ A dog with secondary hypoadrenocorticism only needs to have medication to replace the glucocorticoid steroid cortisol.][ One dog in every 42 diagnosed with hypoadrenocorticism has the secondary form of the disease where mineralocorticoid production remains intact.][
Secondary adrenocortical insufficiency involves only a deficiency of glucocorticoid secretion. Destructive lesions (e.g. neoplasia, inflammation) in the ]pituitary gland
In vertebrate anatomy, the pituitary gland, or hypophysis, is an endocrine gland, about the size of a chickpea and weighing, on average, in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain. The ...
or hypothalamus and chronic administration of exogenous glucocorticoids or megestrol acetate (cats) are the most common causes.
Drug induced
Drug induced (iatrogenic
Iatrogenesis is the causation of a disease, a harmful complication, or other ill effect by any medical activity, including diagnosis, intervention, error, or negligence. "Iatrogenic", ''Merriam-Webster.com'', Merriam-Webster, Inc., accessed 2 ...
) hypoadrenocorticism is caused during abrupt cessation of a steroid
A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and a ...
medication. During steroid treatment, the adrenal glands do not function fully. The body senses the levels of the exogenous
In a variety of contexts, exogeny or exogeneity () is the fact of an action or object originating externally. It contrasts with endogeneity or endogeny, the fact of being influenced within a system.
Economics
In an economic model, an exogeno ...
steroids in the system and therefore does not signal for additional production.[ The usual protocol for stopping steroid medications is not to eliminate them suddenly, but to withdraw from them gradually in a "tapering off" process, which allows the production to adjust to normal. If steroids are abruptly withdrawn, the dormant adrenal glands may not able to reactivate, and the body will need to have its adrenal glucocorticoid hormones replaced by medication.][
]
Diagnosis
Hypoadrenocorticism is often tentatively diagnosed on the basis of history, physical findings, clinical pathology
Clinical pathology is a medical specialty that is concerned with the diagnosis of disease based on the laboratory analysis of bodily fluids, such as blood, urine, and tissue homogenates or extracts using the tools of chemistry, microbiology, ...
, and, for primary adrenal insufficiency, characteristic electrolyte abnormalities.
*Clinical pathology - Abnormalities may be identified on hematology, biochemistry and urinalysis. Elevated concentrations of potassium (hyperkalemia
Hyperkalemia is an elevated level of potassium (K+) in the blood. Normal potassium levels are between 3.5 and 5.0mmol/L (3.5 and 5.0mEq/L) with levels above 5.5mmol/L defined as hyperkalemia. Typically hyperkalemia does not cause symptoms. Occasi ...
), and low sodium and chloride values (hyponatremia
Hyponatremia or hyponatraemia is a low concentration of sodium in the blood. It is generally defined as a sodium concentration of less than 135 mmol/L (135 mEq/L), with severe hyponatremia being below 120 mEq/L. Symptoms can be abs ...
and hypochloremia
Hypochloremia (or Hypochloraemia) is an electrolyte disturbance in which there is an abnormally low level of the chloride ion in the blood. The normal serum range for chloride is 97 to 107 mEq/L.
It rarely occurs in the absence of other abnor ...
) are the classic electrolyte alterations. The sodium/potassium ratio often is <27 (normal is between 27:1 and 40:1) and maybe <20 in animals with primary adrenal insufficiency. However, not all dogs have an abnormal electrolyte
An electrolyte is a medium containing ions that is electrically conducting through the movement of those ions, but not conducting electrons. This includes most soluble salts, acids, and bases dissolved in a polar solvent, such as water. Upon dis ...
ratio during an Addisonian episode.[
*ECG - The severity of the ]ECG
Electrocardiography is the process of producing an electrocardiogram (ECG or EKG), a recording of the heart's electrical activity. It is an electrogram of the heart which is a graph of voltage versus time of the electrical activity of the hear ...
abnormalities correlates with the severity of the hyperkalemia. Therefore, the ECG can be used to identify and estimate the severity of hyperkalemia and to monitor changes in serum potassium during therapy.
*Diagnostic imaging - Abdominal ultrasound may reveal small adrenal gland
The adrenal glands (also known as suprarenal glands) are endocrine glands that produce a variety of hormones including adrenaline and the steroids aldosterone and cortisol. They are found above the kidneys. Each gland has an outer cortex which ...
s, suggesting adrenocortical atrophy. However, finding normal-sized adrenal glands does not rule out hypoadrenocorticism. Rarely, megaesophagus is evident on radiographs.
*ACTH stimulation test
The ACTH test (also called the cosyntropin, tetracosactide, or Synacthen test) is a medical test usually requested and interpreted by endocrinologists to assess the functioning of the adrenal glands' stress response by measuring the adrenal respon ...
- Confirmation requires evaluation of an ACTH stimulation test. Baseline plasma cortisol and urine cortisol/Cr ratios are unreliable for confirming the diagnosis. One major diagnostic criterion is abnormally decreased post-ACTH plasma cortisol. Normal plasma cortisol after ACTH stimulation rules out adrenal insufficiency. The only accurate test for hypoadrenocorticism is an ACTH stimulation test
The ACTH test (also called the cosyntropin, tetracosactide, or Synacthen test) is a medical test usually requested and interpreted by endocrinologists to assess the functioning of the adrenal glands' stress response by measuring the adrenal respon ...
; however, any administration of a steroid other than dexamethasone
Dexamethasone is a glucocorticoid medication used to treat rheumatic problems, a number of skin diseases, severe allergies, asthma, chronic obstructive lung disease, croup, brain swelling, eye pain following eye surgery, superior vena cav ...
will invalidate this test.[ Carry out test by:]
**Measuring serum cortisol before and after administration of ACTH gel or synthetic ACTH
***Normal dogs generally have post stimulation cortisol levels > 10 ug/dl.
***Post stimulation levels < 2 ug/dl is considered diagnostic and most Addison's patients are < 1 ug/dl.
The ACTH stimulation test does not distinguish between primary and secondary hypoadrenocorticism, or adrenocortical destruction caused by mitotane overdose. Differentiation between primary and secondary hypoadrenocorticism can be made by periodically measuring serum electrolytes, baseline endogenous ACTH, or possibly serum or plasma aldosterone during the ACTH stimulation test. While most corticosteroid
Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are involv ...
drugs will invalidate the results of an ACTH test, dexamethasone
Dexamethasone is a glucocorticoid medication used to treat rheumatic problems, a number of skin diseases, severe allergies, asthma, chronic obstructive lung disease, croup, brain swelling, eye pain following eye surgery, superior vena cav ...
may be used in the event of an Addison's emergency without fear of compromising the results of the test.
In general, hypoadrenocorticism is underdiagnosed in dogs, and one must have a clinical suspicion of it as an underlying disorder for many presenting complaints. Females are overrepresented (~70% of cases), and the disease often appears in middle age (four to seven years), although any age or gender may be affected. Dogs with hypoadrenocorticism may also have one of several autoimmune disorder
An autoimmune disease is a condition arising from an abnormal immune response to a functioning body part. At least 80 types of autoimmune diseases have been identified, with some evidence suggesting that there may be more than 100 types. Nearly a ...
s. Because it is an endocrine
The endocrine system is a messenger system comprising feedback loops of the hormones released by internal glands of an organism directly into the circulatory system, regulating distant target organs. In vertebrates, the hypothalamus is the neu ...
disorder, they may also have neuropathy
Peripheral neuropathy, often shortened to neuropathy, is a general term describing disease affecting the peripheral nerves, meaning nerves beyond the brain and spinal cord. Damage to peripheral nerves may impair sensation, movement, gland, or o ...
and some endocrine-related eye diseases.[ (]PDF
Portable Document Format (PDF), standardized as ISO 32000, is a file format developed by Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems. ...
)
Addisonian crisis
If deterioration of the adrenal glands progresses far enough, a dog may experience an Addisonian crisis, an acute episode during which potassium
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosphe ...
levels increase (hyperkalemia
Hyperkalemia is an elevated level of potassium (K+) in the blood. Normal potassium levels are between 3.5 and 5.0mmol/L (3.5 and 5.0mEq/L) with levels above 5.5mmol/L defined as hyperkalemia. Typically hyperkalemia does not cause symptoms. Occasi ...
), disrupting normal functions of the heart
The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide t ...
.[ ]Arrhythmia
Arrhythmias, also known as cardiac arrhythmias, heart arrhythmias, or dysrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. A resting heart rate that is too fast – above 100 beats per minute in adults ...
can result and blood pressure
Blood pressure (BP) is the pressure of circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term "blood pressure" r ...
may drop to dangerously low levels, while the dog's kidneys may cease to function properly. Some 35% of canine Addison's cases are diagnosed as the result of an Addisonian crisis
Adrenal crisis is a potentially life-threatening medical condition requiring immediate emergency treatment. It is a constellation of symptoms (caused by insufficient levels of the hormone cortisol) that indicate severe adrenal insufficiency. This m ...
. It is a medical emergency.
Whipworms
Dogs with infected with the whipworm ''Trichuris trichiura
''Trichuris trichiura, Trichocephalus trichiuris'' or whipworm, is a parasitism, parasitic nematode, roundworm (a type of helminth) that causes trichuriasis (a type of helminthiasis which is one of the neglected tropical diseases) when it infect ...
'' can exhibit low sodium and high potassium values, as is seen in hypoadrenocorticism; however, their ACTH values are normal.
Pacific Rim
Breeds that began in the Pacific Rim, among them Akita
is a Japanese name and may refer to:
Places
* 8182 Akita, a main-belt asteroid
* Akita Castle, a Nara period fortified settlement in Akita, Japan
* Akita Domain, also known as Kubota Domain, feudal domain in Edo period Japan
* Akita, Kumamoto, ...
s and Shiba Inu
The is a breed of hunting dog from Japan. A small-to-medium breed, it is the smallest of the six original and distinct spitz breeds of dog native to Japan. Its name literally translates to "firewood dog".
A small, alert, and agile dog that c ...
s, tend to have higher potassium values in laboratory test, and elevated levels are not abnormal. Dogs who do not have hypoadrenocorticism have normal values on ACTH tests.[
]
Treatment
Aggressiveness of therapy depends on the clinical status of the patient and the nature of the insufficiency (glucocorticoid, mineralocorticoid, or both). Many dogs and cats with primary adrenal insufficiency are presented in Addisonian crisis and require immediate, aggressive therapy. In contrast, secondary insufficiency often has a chronic course.
Hypoadrenocorticism is treated with oral daily administration of fludrocortisone
Fludrocortisone, sold under the brand name Florinef, among others, is a corticosteroid used to treat adrenogenital syndrome, postural hypotension, and adrenal insufficiency. In adrenal insufficiency, it is generally taken together with hydroco ...
(trade name Florinef) or a monthly injection of desoxycorticosterone pivalate
Deoxycorticosterone pivalate (DOCP), also known as desoxycorticosterone trimethyl acetate (DOC-TMA or DCT) and sold under the brand names Zycortal, Percorten V, and Percorten M, is a mineralocorticoid medication and a mineralocorticoid ester. It ...
, DOCP (Percorten-V or Zycortal) and daily prednisone
Prednisone is a glucocorticoid medication mostly used to immunosuppressive drug, suppress the immune system and decrease inflammation in conditions such as asthma, COPD, and rheumatologic diseases. It is also used to treat high blood calcium ...
or prednisolone
Prednisolone is a steroid medication used to treat certain types of allergies, inflammatory conditions, autoimmune disorders, and cancers. Some of these conditions include adrenocortical insufficiency, high blood calcium, rheumatoid arthrit ...
. One drug is needed to supplement mineralcortidoids and the other to supplement corticosteroids. This effectively replaces what the adrenal cortex is failing to produce. Routine blood work is necessary in the initial stages until a maintenance dose is established. Most of the medications used in the therapy of hypoadrenocorticism cause excessive thirst and urination. It is absolutely vital to provide fresh drinking water for a canine with this disorder.
If the owner knows about an upcoming stressful situation (shows, traveling etc.), the animals generally need an increased dose of prednisone (2-4 times maintenance) to help deal with the added stress. Avoidance of stress is important for dogs with hypoadrenocorticism. Physical illness also stresses the body and may mean that the medication(s) need to be adjusted during this time. Most dogs with hypoadrenocorticism have an excellent prognosis after proper stabilization and treatment.[
]
Addisonian crisis
Treatment is directed towards (1) correcting hypotension, hypovolemia, electrolyte imbalances, and metabolic acidosis
Metabolic acidosis is a serious electrolyte disorder characterized by an imbalance in the body's acid-base balance. Metabolic acidosis has three main root causes: increased acid production, loss of bicarbonate, and a reduced ability of the kidneys ...
; (2) improving vascular integrity, and (3) providing an immediate source of glucocorticoids. Rapid correction of hypovolemia is the first priority.
Restoring blood volume is vital to correcting hypotension, hypovolemia, and addressing electrolyte and metabolic imbalances. This is achieved by the rapid administration of fluids. This helps to correct hyponatremia, restore perfusion to organs, and reduce hyperkalemia through increased GFR and dilution effects. Further treatment of hyperkalemia is addressed if necessary. Often, the fluid therapy can sufficiently address hyperkalemia, but in the presence of significant cardiac abnormalities, the addition of calcium gluconate
Calcium gluconate is a mineral supplement and medication. As a medication it is used by injection into a vein to treat low blood calcium, high blood potassium, and magnesium toxicity. Supplementation is generally only required when there is no ...
may be necessary in addition to glucose, insulin, or bicarb to promote intracellular shift of potassium.
Most patients show dramatic improvement within 24 to 48 hours of appropriate fluid and glucocorticoid therapy. Over the ensuing 2 to 4 days, a gradual transition from IV fluids
Intravenous therapy (abbreviated as IV therapy) is a medical technique that administers fluids, medications and nutrients directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutrie ...
to oral water and food is undertaken, and maintenance mineralocorticoid and glucocorticoid therapy is initiated. Failure to make this transition smoothly should raise suspicion of insufficient glucocorticoid supplementation, concurrent endocrinopathy (e.g. hypothyroidism
Hypothyroidism (also called ''underactive thyroid'', ''low thyroid'' or ''hypothyreosis'') is a disorder of the endocrine system in which the thyroid gland does not produce enough thyroid hormone. It can cause a number of symptoms, such as po ...
), or concurrent illness (especially renal damage).
It is important that after the crisis is corrected that the patient is put on a maintenance therapy of corticosteroids and mineralocorticoids.
Epidemiology
Hypoadrenocorticism is typically a disease of young to middle-aged female dogs, although Standard Poodles and Bearded Collies of both sexes are prone to the condition.
Hypoadrenocorticism is an inherited disease in the following breeds (and therefore a higher proportion of dogs within these breeds are affected, compared to other breeds):
* Bearded Collie
The Bearded Collie, or Beardie, is a herding breed of dog once used primarily by Scottish shepherds, but now mostly a popular family companion.
Bearded Collies have an average weight of . Males are around tall at the withers while females are ...
* Nova Scotia Duck Tolling Retriever
The Nova Scotia Duck Tolling Retriever is a medium-sized gundog bred primarily for hunting. It is often referred to as a "toller". It is the smallest of the retrievers, and is often mistaken for a small Golden Retriever. Tollers are intelligent, ...
* Portuguese Water Dog
The Portuguese Water Dog originated from the Algarve region of Portugal. From there the breed expanded to all around Portugal's coast, where they were taught to herd fish into fishermen's nets, retrieve lost tackle or broken nets, and act as ...
* Standard Poodle
, nickname =
, stock =
, country = Germany or France (see history)
, height =
, maleheight =
, femaleheight =
, weight =
, maleweight =
, femaleweight =
, coat ...
Some breeds are at increased risk
In simple terms, risk is the possibility of something bad happening. Risk involves uncertainty about the effects/implications of an activity with respect to something that humans value (such as health, well-being, wealth, property or the environme ...
of hypoadrenocorticism:
* Airedale Terrier
The Airedale Terrier (often shortened to "Airedale"), also called Bingley Terrier and Waterside Terrier, is a dog breed of the terrier type that originated in the valley (''dale'') of the River Aire, in the West Riding of Yorkshire, England. It ...
* Basset Hound
The Basset Hound is a short-legged breed of dog in the hound family. The Basset is a scent hound that was originally bred for the purpose of hunting hare. Their sense of smell and ability to ''ground-scent'' is second only to the Bloodhound.Har ...
* Bearded Collie
The Bearded Collie, or Beardie, is a herding breed of dog once used primarily by Scottish shepherds, but now mostly a popular family companion.
Bearded Collies have an average weight of . Males are around tall at the withers while females are ...
* Great Dane
The Great Dane is a large sized dog breed originating from Germany. The Great Dane descends from hunting dogs from the Middle Ages used to hunt wild boar and deer, and as guardians of German nobility. It is one of the largest breeds in the world ...
* Rottweiler
The Rottweiler (, ) is a breed of domestic dog, regarded as medium-to-large or large. The dogs were known in German as , meaning Rottweil butchers' dogs, because their main use was to herd livestock and pull carts laden with butchered mea ...
* Springer Spaniels: English Springer Spaniel
The English Springer is a dog breed, breed of gun dog in the Spaniel group traditionally used for flushing and retrieving game. It is an affectionate, excitable breed with a typical lifespan of twelve to fourteen years. They are very similar ...
and Welsh Springer Spaniel
The Welsh Springer Spaniel (''Welsh'': ''Llamgi Cymru'') is a dog breed, breed of dog and a member of the spaniel family. Thought to be comparable to the old Land Spaniel, they are similar to the English Springer Spaniel and historically have ...
* Saint Bernard
* Soft-Coated Wheaten Terrier
* West Highland white terrier
The West Highland White Terrier, commonly known as the Westie, is a breed of dog from Scotland with a distinctive white harsh coat with a somewhat soft white undercoat. It is a medium-sized terrier, although with longer legs than other Scott ...
[
Some breeds have a reduced ]risk
In simple terms, risk is the possibility of something bad happening. Risk involves uncertainty about the effects/implications of an activity with respect to something that humans value (such as health, well-being, wealth, property or the environme ...
of hypoadrenocorticism:
* Boxer Boxer most commonly refers to:
* Boxer (boxing), a competitor in the sport of boxing
*Boxer (dog), a breed of dog
Boxer or boxers may also refer to:
Animal kingdom
* Boxer crab
* Boxer shrimp, a small group of decapod crustaceans
* Boxer snipe ee ...
* Cocker Spaniel
Cocker Spaniels are dogs belonging to two breeds of the spaniel dog type: the American Cocker Spaniel and the English Cocker Spaniel of which are commonly called simply Cocker Spaniel in their countries of origin. In the early 20th century, Cocker ...
* Golden Retriever
The Golden Retriever is a Scottish breed of retriever dog of medium size. It is characterised by a gentle and affectionate nature and a striking golden coat. It is commonly kept as a pet and is among the most frequently registered breeds ...
* Pit Bull Terrier
Pit bull is a term used in the United States for a type of dog descended from bulldogs and terriers, while in other countries such as the United Kingdom the term is used as an abbreviation of the American Pit Bull Terrier breed. The term was ...
* Lhasa Apso
The Lhasa Apso ( ) is a non-sporting dog breed originating in Tibet. It has traditionally been used as an interior sentinel.
Etymology
Lhasa is the capital city of Tibet, and ''apso'' is a word from the Tibetan language. There is some deba ...
* Yorkshire Terrier
The Yorkshire Terrier (often shortened as Yorkie) is one of the smallest dog breeds of the terrier type and indeed of any dog breed. The breed developed during the 19th century in Yorkshire, England.[Thomas Addison
Thomas J Addison (April 179329 June 1860) was an English physician, chef, and scientist. He is traditionally regarded as one of the "great men" of Guy's Hospital in London.
Among other pathologies, he discovered Addison's disease (a degenerati ...]
.
References
{{DEFAULTSORT:Hypoadrenocorticism in dogs
Dog diseases