Systemic lupus erythematosus in the context of "Flare-up"

Immunosuppression is a reduction of the activation or efficacy of the immune system. Some portions of the immune system itself have immunosuppressive effects on other parts of the immune system, and immunosuppression may occur as an adverse reaction to treatment of other conditions.

In general, deliberately induced immunosuppression is performed to prevent the body from rejecting an organ transplant. Additionally, it is used for treating graft-versus-host disease after a bone marrow transplant, or for the treatment of auto-immune diseases such as systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, or Crohn's disease. This is typically done using medications, but may involve surgery (splenectomy), plasmapheresis, or radiation. A person who is undergoing immunosuppression, or whose immune system is weak for some other reasons (such as chemotherapy or HIV), is said to be immunocompromised.

The Epstein–Barr virus (EBV), also known as human herpesvirus 4 (HHV-4), is one of the nine known human herpesvirus types in the herpes family, and is one of the most common viruses in humans. EBV is a double-stranded DNA virus. EBV is the first identified oncogenic virus, a virus that can cause cancer. EBV establishes a permanent infection in human B cells. It uncommonly causes infectious mononucleosis and is also tightly linked to many malignant diseases (cancers and autoimmune diseases). Various vaccine formulations have been tested in humans and other animals; however, none of them were able to prevent EBV infection, thus, no vaccine has been approved to date.

Infectious mononucleosis ("mono" or "glandular fever"), is characterized by extreme fatigue, fever, sore throat, and swollen lymph nodes. EBV is also associated with various non-malignant, premalignant, and malignant EBV-associated lymphoproliferative diseases such as Burkitt lymphoma, hemophagocytic lymphohistiocytosis, and Hodgkin's lymphoma; non-lymphoid malignancies such as gastric cancer and nasopharyngeal carcinoma; and conditions associated with human immunodeficiency virus such as hairy leukoplakia and central nervous system lymphomas. The virus is also associated with the childhood disorders of Alice in Wonderland syndrome and acute cerebellar ataxia and, by some evidence, higher risks of developing certain autoimmune diseases, especially dermatomyositis, systemic lupus erythematosus, rheumatoid arthritis, and Sjögren's syndrome. About 200,000 cancer cases globally per year are thought to be attributable to EBV. In 2022, a large study following 10 million active US military over 20 years suggested EBV as the leading cause of multiple sclerosis (MS), with a recent EBV infection causing a 32-fold increase in MS risk development.

Relapsing–remitting is a medical term referring to a presentation of disease symptoms that become worse over time (relapsing), followed by periods of less severe symptoms that do not completely cease (partial remitting). The term is used to describe a type of multiple sclerosis called relapsing–remitting multiple sclerosis, where unpredictable relapses are followed by remission for months to years.

The term is also used to describe palindromic rheumatism in the context of rheumatoid arthritis, catatonia, lupus, mental disorders, and experimental autoimmune encephalomyelitis.

Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and hands are involved, with the same joints typically involved on both sides of the body. The disease may also affect other parts of the body, including skin, eyes, lungs, heart, nerves, and blood. This may result in a low red blood cell count, inflammation around the lungs, and inflammation around the heart. Fever and low energy may also be present. Often, symptoms come on gradually over weeks to months.

While the cause of rheumatoid arthritis is not clear, it is believed to involve a combination of genetic and environmental factors. The underlying mechanism involves the body's immune system attacking the joints. This results in inflammation and thickening of the joint capsule. It also affects the underlying bone and cartilage. The diagnosis is mostly based on a person's signs and symptoms. X-rays and laboratory testing may support a diagnosis or exclude other diseases with similar symptoms. Other diseases that may present similarly include systemic lupus erythematosus, psoriatic arthritis, and fibromyalgia among others.

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". Prominent examples include celiac disease, diabetes mellitus type 1, Henoch–Schönlein purpura, systemic lupus erythematosus, Sjögren syndrome, eosinophilic granulomatosis with polyangiitis, Hashimoto's thyroiditis, Graves' disease, idiopathic thrombocytopenic purpura, Addison's disease, rheumatoid arthritis, ankylosing spondylitis, polymyositis, dermatomyositis, and multiple sclerosis. Autoimmune diseases are very often treated with steroids.

Autoimmunity means presence of antibodies or T cells that react with self-protein and is present in all individuals, even in normal health state. It causes autoimmune diseases if self-reactivity can lead to tissue damage.

Epstein–Barr virus–associated lymphoproliferative diseases (also abbreviated EBV-associated lymphoproliferative diseases or EBV+ LPD) are a group of disorders in which one or more types of lymphoid cells (a type of white blood cell), i.e. B cells, T cells, NK cells, and histiocytic-dendritic cells, are infected with the Epstein–Barr virus (EBV). This causes the infected cells to divide excessively, and is associated with the development of various non-cancerous, pre-cancerous, and cancerous lymphoproliferative disorders (LPDs). These LPDs include the well-known disorder occurring during the initial infection with the EBV, infectious mononucleosis, and the large number of subsequent disorders that may occur thereafter. The virus is usually involved in the development and/or progression of these LPDs although in some cases it may be an "innocent" bystander, i.e. present in, but not contributing to, the disease.

EBV-associated LPDs are a subcategory of EBV-associated diseases. Non-LPD that have significant percentages of cases associated with EBV infection (see Epstein–Barr virus infection) include the immune disorders of multiple sclerosis and systemic lupus erythematosus; malignancies such as stomach cancers, soft tissue sarcomas, leiomyosarcoma, and undifferentiated nasopharyngeal cancer; the childhood disorders of Alice in Wonderland syndrome; and acute cerebellar ataxia.