The adrenal glands are small, triangle-shaped organs situated directly above each kidney, forming part of the body’s endocrine system. Their role involves producing hormones that regulate metabolism, blood pressure, and the body’s reaction to stress. Inflammation of these glands, known as adrenalitis, impairs these functions, leading to systemic issues. When adrenalitis causes a significant loss of function, it results in primary adrenal insufficiency, which can be a serious medical concern.
Understanding Adrenal Gland Function
The adrenal gland is structurally divided into two distinct regions, each producing a different set of hormones. The outer layer, the adrenal cortex, creates the majority of the gland’s regulatory hormones. This cortex is segmented into three zones that produce steroid hormones necessary for survival.
The outermost layer of the cortex synthesizes mineralocorticoids, particularly aldosterone, which manages salt and water balance by acting on the kidneys. Aldosterone helps maintain stable blood pressure and regulates sodium and potassium concentration. The middle and largest zone produces glucocorticoids, primarily cortisol, a hormone released in response to stress. Cortisol also controls the body’s use of fats, proteins, and carbohydrates, while regulating the immune response.
Lying at the center is the adrenal medulla, an extension of the sympathetic nervous system. This inner region is responsible for the rapid release of catecholamines, specifically epinephrine and norepinephrine. These hormones drive the “fight-or-flight” response, quickly increasing heart rate, blood flow to muscles, and the force of heart contractions.
Primary Triggers of Adrenalitis
Inflammation of the adrenal glands (adrenalitis) is most commonly caused by an autoimmune response targeting hormone-producing cells. Autoimmune adrenalitis accounts for the vast majority of cases in industrialized nations. The immune system mistakenly produces antibodies against the 21-hydroxylase enzyme, leading to the gradual destruction of the adrenal cortex tissue. Chronic adrenalitis often progresses to primary adrenocortical insufficiency.
Infections represent another major category of triggers, historically dominated by tuberculosis, which remains frequent in developing countries. Other infectious agents, such as cytomegalovirus (CMV), human immunodeficiency virus (HIV), and various fungi, can also damage the adrenal tissue. These infectious causes destroy the cortex, resulting in a loss of hormone production.
A more acute, life-threatening form of adrenalitis can be triggered by hemorrhage or bleeding into the glands. Adrenal hemorrhage is often associated with severe bacterial infections like meningococcemia, or conditions such as trauma, sepsis, or the use of anticoagulant medications. In these cases, the rapid destruction of glandular tissue causes an immediate and severe drop in hormone levels, precipitating an acute medical emergency.
Recognizing the Physical Manifestations
The physical signs of adrenalitis leading to chronic insufficiency are often subtle and develop slowly. Primary symptoms include profound, unexplained fatigue that is not relieved by rest. This weakness is often accompanied by unintentional weight loss and a reduction in appetite.
Gastrointestinal issues are frequently reported, including chronic nausea, vomiting, and abdominal pain. Due to insufficient aldosterone production, many individuals crave salty foods as the body attempts to restore lost sodium. This mineral imbalance also contributes to orthostasis, a form of low blood pressure causing dizziness when standing up quickly.
Hyperpigmentation, or the darkening of the skin, is a distinct finding in primary adrenal insufficiency. This change is most pronounced in sun-exposed areas, skin creases, and on the mucous membranes of the mouth. The darkening results from the pituitary gland releasing excessive hormones to stimulate the failing adrenals, which cross-reacts to increase melanin production.
A person with chronic adrenalitis may eventually experience an acute, severe worsening known as an adrenal crisis. This medical emergency can be triggered by physical stress like infection, injury, or surgery. Symptoms include sudden, penetrating pain in the lower back, legs, or abdomen, often accompanied by severe vomiting and diarrhea leading to dehydration. The rapid drop in blood pressure can quickly lead to shock, confusion, and loss of consciousness, requiring immediate medical intervention.
Diagnosis and Medical Management
The diagnostic process for adrenalitis and resulting insufficiency begins with laboratory testing to measure hormone levels. A low morning cortisol level suggests the possibility of adrenal insufficiency. The adrenocorticotropic hormone (ACTH) stimulation test is the definitive method used to confirm the diagnosis.
During the ACTH stimulation test, a baseline blood sample is taken, followed by an injection of synthetic ACTH. Samples are collected again after 30 and 60 minutes to measure the adrenal glands’ response. A lack of an appropriate rise in cortisol confirms primary adrenal insufficiency, indicating the glands cannot produce necessary hormones.
Imaging studies, such as CT or MRI scans, may visualize the adrenal glands and determine the underlying cause. Scans can reveal signs of autoimmune damage, like gland atrophy, or infectious causes, such as calcification or enlargement. The primary treatment for chronic adrenal insufficiency is hormone replacement therapy. This management involves taking glucocorticoids (e.g., hydrocortisone) and mineralocorticoids (e.g., fludrocortisone) to replace lost cortisol and aldosterone.