More than 80 diseases occur as a result of the immune system attacking the body’s own organs, tissues, and cells. Some of the more common autoimmune diseases include type 1 diabetes, rheumatoid arthritis, systemic lupus erythematosus, and inflammatory bowel disease.

Although the causes of many autoimmune diseases remain unknown, a person’s genes in combination with infections and other environmental exposures are likely to play a significant role in disease development. Treatments are available for many autoimmune diseases, but cures have yet to be discovered.

Autoimmune lymphoproliferative syndrome (ALPS) is a rare genetic disorder of the immune system that affects both children and adults. In ALPS, unusually high numbers of white blood cells called lymphocytes accumulate in the lymph nodes, liver, and spleen, which can lead to enlargement of these organs. ALPS can cause numerous autoimmune problems such as anemia (low count of red blood cells), thrombocytopenia (low count of platelets), and neutropenia (low count of neutrophils, the most common type of white blood cell in humans).

APS-1 is a genetic immune disorder that causes a diverse range of symptoms, including autoimmunity against different types of organs and an increased susceptibility to candidiasis, a fungal infection caused by Candida yeast.

APS-1 has other names, including autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED); autoimmune polyendocrinopathy, type 1; and polyglandular autoimmune (PGA) syndrome, type 1.

CARD9 deficiency is a genetic immune disorder that results in susceptibility to fungal infections like candidiasis, which is caused by the yeast fungus Candida. Typically, Candida and other fungi are present on the skin and mucosal surfaces, like the mouth, and do not cause severe problems in healthy people. However, people with deficient immune systems are more vulnerable to symptomatic infection.

Chronic granulomatous disease (CGD) is a genetic disorder in which white blood cells called phagocytes are unable to kill certain bacteria and fungi. People with CGD have increased susceptibility to infections caused by certain types of bacteria and fungi, such as Staphylococcus aureus, Serratia marcescens, Burkholderia cepacia, Nocardia species, and Aspergillus species.

Common variable immunodeficiency (CVID) is characterized by low levels of antibodies and an increased risk of infections. Although the disease usually is diagnosed in adults, it also can occur in children. CVID also is known as hypogammaglobulinemia, adult-onset agammaglobulinemia, late-onset hypogammaglobulinemia, and acquired agammaglobulinemia.

Congenital neutropenia syndromes are a group of disorders characterized by low levels of neutrophils—white blood cells necessary for combating infections—present from birth. Congenital neutropenia syndromes also may be called congenital agranulocytosis, severe congenital neutropenia, severe infantile genetic neutropenia, infantile genetic agranulocytosis or Kostmann disease.

CTLA4 deficiency impairs normal regulation of the immune system, resulting in excessive numbers of immune cells called lymphocytes, autoimmunity, low levels of antibodies, and recurrent infections.

DOCK8 deficiency is a rare immune disorder named after the mutated gene responsible for the disease. The disorder causes decreased numbers and dysfunction of immune cells, as well as poor ability of immune cells to move across dense tissues like the skin. The abnormalities resulting from DOCK8 defects lead to recurrent infections.

GATA2 deficiency is a genetic disease that can manifest as five distinct syndromes: monocytopenia and mycobacterial infection syndrome; dendritic cell, monocyte, B, and natural killer lymphoid deficiency; familial myelodysplastic syndromes (MDS)/acute myeloid leukemia (AML); Emberger syndrome; or natural killer (NK) cell deficiency.

Glycosylation refers to the attachment of sugars to proteins, a normal process required for the healthy function of cells. Defects in glycosylation can impair the growth or function of cells and tissues in the body, and in some cases, the immune system is disrupted, resulting in immunodeficiency.

People with hyper-immunoglobulin E syndrome, or HIES, have recurrent infections of the skin and lungs caused by bacteria. Patients with HIES typically also have eczema, very high levels of a type of antibody called immunoglobulin E (IgE), distinct facial features, and a tendency to experience bone fractures. HIES is also called Job’s Syndrome.

Hyper-IgM syndromes are conditions in which the immune system fails to produce normal levels of immunoglobulin A (IgA), IgG, and IgE antibodies but can produce normal or elevated levels of IgM. Various gene defects can cause hyper-IgM syndromes.

The immune system is a network of cells, tissues, and organs that work together to protect the body from infection. Immune cells communicate using a series of signals that can be secreted into the cell’s environment or expressed on the surface of the cell. Interferon gamma (IFN-γ), interleukin 12 (IL-12), and interleukin 23 (IL-23) are key signal molecules that raise an alert against bacteria and other infectious microbes.

Leukocyte adhesion deficiency (LAD) is an immune deficiency in which immune cells called phagocytes are unable to move to the site of an infection to fight off invading germs. This inability to fight germs results in recurrent, life-threatening infections and poor wound healing.

Discovered by NIH scientists in 2013, PI3 kinase (PI3K) disease is named after the genetic mutations that cause the disorder and its symptoms. People with PI3K disease have a weakened immune system and experience frequent bacterial and viral infections. PI3K disease also increases a person’s risk of lymphoma, a type of immune cell cancer.

The disease also is called PI3K-p110δ activating mutation causing senescent T cells, lymphadenopathy, and immunodeficiency (PASLI) or activating PI3K delta syndrome (APDS).

PLAID and PLAID-like diseases are rare immune disorders with overlapping features, and an allergic response to cold, called cold urticaria, is the most distinct symptom.

Primary immune deficiency diseases (PIDDs) are rare, genetic disorders that impair the immune system. Without a functional immune response, people with PIDDs may be subject to chronic, debilitating infections, such as Epstein-Barr virus (EBV), which can increase the risk of developing cancer. Some PIDDs can be fatal. PIDDs may be diagnosed in infancy, childhood, or adulthood, depending on disease severity.

SCID is a group of rare disorders caused by mutations in different genes involved in the development and function of infection-fighting T, B, and natural killer cells. Infants with SCID appear healthy at birth but are highly susceptible to severe infections. The condition is fatal, usually within the first year or two of life, unless infants receive immune-restoring treatments, such as transplants of blood-forming stem cells, gene therapy, or enzyme therapy. More than 80 percent of SCID infants do not have a family history of the condition.

WHIM syndrome is a rare immune disorder named after its symptoms: warts, hypogammaglobulinemia (low antibody levels), infections, and myelokathexis (inability of white blood cells to move from the bone marrow into the bloodstream). People with WHIM syndrome have low levels of infection-fighting white blood cells, especially neutrophils, in their bloodstream. This deficiency predisposes them to frequent infections and persistent warts.

People with WAS have problems with their B cells, T cells, and platelets (blood components that aid in clotting). This can result in prolonged episodes of bleeding, recurrent bacterial and fungal infections, and increased risk of cancers and autoimmune diseases.

LA is an inherited immune disorder caused by an inability to produce B cells or the immunoglobulins (antibodies) that the B cells make. The mutated gene responsible for XLA (Bruton tyrosine kinase or BTK) is located on the X chromosome. XLA is also called Bruton type agammaglobulinemia, X-linked infantile agammaglobulinemia, and congenital agammaglobulinemia.

XLP primarily affects boys and is characterized by a life-long vulnerability to Epstein-Barr virus (EBV), a common type of herpesvirus that usually does not cause symptoms other than a brief infection or mononucleosis. Boys with XLP, however, can have severe reactions to EBV infections.