Like many illnesses, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) causes remain unknown. ME/CFS may have more than one underlying cause, resulting in disease in persons with the condition (see below). Some possible causes and correlations are listed below.
Infection
ME/CFS flue-like symptoms led experts to believe that an infection may cause ME/CFS. As a result, around one in ten patients who contract Epstein-Barr virus, Ross River virus, or Coxiella burnetti will develop ME/CFS symptoms. People who developed severe symptoms of these infections are more likely to develop ME/CFS symptoms in the future than those who developed mild symptoms. However, these infections haven’t been present in all cases with ME/CFS.
Without evidence, Candida albicans, herpesvirus 6, enterovirus, rubella, bornaviruses, mycoplasma, and human immunodeficiency virus have been linked to ME/CFS (HIV).
Perhaps ME/CFS results from an abnormality in the immune system and how it responds to illness or stressful situations. Some of the symptoms of ME/CFS, such as rheumatoid arthritis, are comparable to those of autoimmune diseases. Both ME/CFS and most autoimmune disorders are more common in women, associated with elevated inflammation. Patients with ME/CFS, on the other hand, show no symptoms of autoimmune illness, such as tissue damage.
Immune System Imbalance
Increased chronic cytokines, proteins produced by the immune system, and regulating other cells’ behavior, production may cause ME/CFS for an extended period, altering the body’s ability to respond to stress.
The body’s immune system relies on natural killer (NK) cells to fight disease. The NK cells of many ME/CFS patients have a decreased capacity for defending themselves against infection. According to research, the more severely ill ME/CFS individuals are, the worse their NK cell performance is. Research studies are the only place where NK cell function tests can be trusted. Because of this issue, NK cell function testing is currently ineffective for healthcare professionals. NK cell dysfunction can also occur in other diseases. Hence it cannot be utilized to diagnose ME/CFS.
T-cell activation indicators vary from person to person. T-cells are immune system cells that assist trigger and dampening the immunological response to infections. Having too much or too little activity negatively affects the immune system. These changes in T-cell activation may not be seen in all people with ME/CFS.
Stress Caused Chemical Changes
The hypothalamic-pituitary-adrenal axis is affected by physical or mental stress (HPA axis). The HPA axis, a complex network that controls many other functions, including digestion, energy usage, and mood, regulates our body’s response to stress.
Adrenal glands are connected to two nervous system glands (hypothalamus and pituitary) (small organs that reside on top of the kidneys). Hypothalamus and pituitary glands produce cortisol, CRH, and other hormones.
Imbalances in these hormones may negatively impact the immune system. Cortisol, the so-called “stress hormone,” aids in the reduction of inflammation and the relaxation of the immune system. As a result, the immune system may become overactive because of a shortage of cortisol.
Preexisting health conditions, such as chronic physical or emotional stress, are common in patients with ME/CFS. However, even though some ME/CFS patients have lower cortisol levels than healthy individuals, their cortisol levels are still within the acceptable range. Acceptable cortisol range with ME/CFS makes cortisol levels an unreliable diagnostic tool.
Cellular Energy Production
Persons with ME/CFS and healthy people have distinct changes in how their cells obtain energy. Researchers need to conduct further investigation into how these findings may be affecting the sickness, though.
Genetics
ME/CFS can affect members of the same family simultaneously.
Twin and family studies imply that genetics and environment may influence ME/CFS. But the exact mechanism still eludes scientists.