Fatigue and Nausea Could Mean Addison's Disease

Hormones are a vital part of our bodies, functioning as chemical messengers sending signals to the bloodstream and tissues, and playing a critical role in our growth and development. When your body fails to produce enough of certain hormones, various medical conditions can arise.

One such condition is Addison's disease, the symptoms of which are fatigue, gastrointestinal abnormalities, nausea, dizziness and darkening of the skin.

A look at prevalence

Addison's disease, sometimes referred to as primary adrenal insufficiency, was named after Thomas Addison, a 19th-century British doctor mostly associated with Guy's Hospital in London.

"Addison's disease is a specific type of primary adrenal insufficiency caused by autoimmunity. Primary adrenal insufficiency is a condition in which the adrenal glands do not make enough cortisol and aldosterone, hormones necessary to support daily function," said Lisal Folsom, M.D., an endocrinologist at Norton Children's Medical Group in Louisville, Kentucky. "Cortisol is a glucocorticoid and plays a role in metabolism as well as the body's response to stress and inflammation."

Cortisol also helps maintain blood pressure, heart function, the immune system and blood sugar levels. Aldosterone is a mineralocorticoid that the body uses to balance sodium and potassium levels, which helps maintain normal blood pressure.

Addison's disease, and primary adrenal insufficiency in general, is quite rare: Only 1 in 100,000 people in the United States have Addison's disease. But many cases are likely undiagnosed, so it is difficult to determine an exact number. In some instances, it's been suggested someone could have a genetic predisposition to develop this disease.

Causes and symptoms

In most cases, Addison's disease is caused by an autoimmune reaction where the immune system attacks the outer layer of cells of the adrenal glands—the adrenal cortex—where the steroid hormones cortisol and aldosterone are produced.

Tuberculosis was once cited as the main cause of Addison's disease, and still is in developing countries. Less common causes include HIV-related infections and fungal infections, cancer that has spread from another area in the body, bleeding into the adrenal glands, surgical removal of the adrenal glands, amyloidosis and various genetic defects. The damage to adrenal glands occurs over time.

Signs and symptoms of primary adrenal insufficiency may include fatigue, weight loss, dizziness when standing up, a loss of appetite, abdominal pain, nausea, vomiting, a darkening of the skin, particularly in the gums and skin creases, low blood pressure and overall weakness.

In most cases, Addison's disease is caused by an autoimmune reaction where the immune system attacks the outer layer of cells of the adrenal glands.

"My symptoms were extreme fatigue, salt craving, huge water/electrolytes imbalance, constant dehydration, loss of appetite, low blood sugar, sweating and vomiting," said Ali, a stay-at-home mom in North Carolina who preferred not to give her last name.

Other symptoms of Addison's disease can be abnormal menstrual periods, depression, diarrhea and irritability.

Patients should know that a medical crisis from Addison's disease can result in death. These crises are characterized by confusion, trouble staying awake or loss of consciousness, high fever, sudden deep lower back and belly pain, severe vomiting and diarrhea.

Diagnosis and treatment

Addison's disease is not on the primary list of conditions to look for when a patient complains of these symptoms, but may instead be identified from a routine blood test reporting low levels of sodium as well as elevated levels of potassium.

"The first step to diagnosing adrenal insufficiency is to check a morning blood cortisol level," Folsom explained. "Cortisol production is closely linked to our sleep/wake cycle, with the highest levels produced around the time we wake up, so obtaining this measurement right around 8 a.m. is typically the best time. Sometimes, physicians will also obtain an adrenocorticotropic hormone [ACTH] level at the same time to determine whether the deficiency lies with the adrenal glands [primary] or the pituitary gland [secondary].

"If the morning cortisol level is low, the next step would be an ACTH stimulation test," she added. "During this test, the person is given a synthetic hormone similar to ACTH, with subsequent monitoring of cortisol levels to assess the body's response. To assess for autoimmunity, adrenal antibodies can be measured."

Addison's disease is not on the primary list of conditions to look for when a patient complains of these symptoms.

X-ray imaging, such as computed tomography (CT scan), can be used to check the size of the adrenal gland, looking for any calcification or other signs of concern.

"I was diagnosed after one of the cancer treatments I had taken destroyed my thyroid and adrenal glands," Ali said. "It took many months of going to the ER without understanding why it kept happening. Finally, a doctor ran a full-panel blood test and realized it was Addison's."

Ali was given a prescription for oral hydrocortisone. The treatment is used to replace the adrenal hormones no longer being produced, and patients typically take glucocorticoids to replace the missing cortisol and mineralocorticoids to replace the aldosterone. These medications are taken orally daily. During times of physical stress, such as illness, accident or surgery, people need extra stress hormones, so patients "stress-dose" glucocorticoids to provide additional coverage for these physical stressors.

In search of support

There is no cure for Addison's disease. After diagnosis, people with Addison's need to take medication for the rest of their lives to manage symptoms. Generally, they can lead full, healthy lives, but Addison's effects remain.

"It's changed the entire quality of my life," Ali said. "I'm not able to physically do what I could before. I'm weaker, I have no stamina. I get tired very easily."

People who suffer from Addison's disease are advised to wear a bracelet at all times identifying their diagnosis, so medical personnel are immediately aware of their medical status if necessary.

Some organizations that offer support for people with Addison's disease or other adrenal insufficiency include Adrenal Insufficiency United, the National Adrenal Diseases Foundation and the Pituitary Network Organization.