Types of PI

Activated PI3K-delta syndrome is a disorder that impairs the immune system. Individuals with this condition often have low numbers of white blood cells (lymphopenia), particularly B cells and T cells. Normally, these cells recognize and attack foreign invaders, such as viruses and bacteria, to prevent infection. Beginning in childhood, people with activated PI3K-delta syndrome develop recurrent infections, particularly in the lungs, sinuses, and ears. Over time, recurrent respiratory tract infections can lead to a condition called bronchiectasis, which damages the passages leading from the windpipe to the lungs (bronchi) and can cause breathing problems. People with activated PI3K-delta syndrome may also have chronic active viral infections, commonly Epstein-Barr virus or cytomegalovirus infections. Credit: Genetics Home Reference

Adenosine deaminase deficiency (also called ADA deficiency or ADA-SCID) is an autosomal recessive metabolic disorder that causes immunodeficiency. It occurs in fewer than one in 100,000 live births worldwide. It accounts for about 15% of all cases of severe combined immunodeficiency (SCID). ADA-SCID is a rare disease in which patients cannot make lymphocytes (a type of white blood cell) and, as a result, have a severely deficient immune system. A faulty gene inherited from both parents stops production of an essential protein called adenosine deaminase (ADA), which is particularly important for the formation of lymphocytes and a functioning immune system. Children born with ADA-SCID have an impaired ability to fight off everyday infections resulting in severe and life-threatening illness. They rarely survive beyond 1-2 years unless immune function is restored. Patients with ADA-SCID initially take antibiotics and antifungal treatments to help protect themselves from serious infections, but most require a bone marrow transplant from a matched donor. However, the effectiveness of these transplants is highly dependent upon how close the match is between donor and patient. If no suitable donors are available, gene therapy, if approved, will provide another option. Credits: Immune Deficiency Foundation, Genetics Home Reference

This one of the various antibody deficiency disorders. Individuals with antibody deficiencies tend to get upper respiratory infections or infections of the sinuses or lungs (eg. streptococcus pneumonia, hemophilus influenzae). Those with Antibody Deficiency with Normal/Elevated Immunoglobulins have severe infections similar to patients with Common Variable Immunodeficiency (CVID), but their immunoglobulin levels are normal/elevated. Credit: Immune Deficiency Foundation

Ataxia-Telangiectasia (A-T) is a condition that affects multiple body systems. People with A-T have an unsteady, wobbly gait (ataxia) which worsens with age. Typically, they require a wheelchair for mobility by adolescence. Individuals with A-T have dilated, corkscrew-shaped blood vessels called "telangiectasia" on the whites of the eyes and certain areas of skin. A major symptom is a deficient immune system, often making those with A-T susceptible to lung infections. Individuals with A-T also have higher chances of getting cancer, particularly lymphoma, and leukaemia. The condition occurs in 1 in 40,000 to 100,000 people worldwide. Credits: Immune Deficiency Foundation, Genetics Home Reference

Autosomal dominant hyper-IgE syndrome (AD-HIES), also known as Job syndrome, is a condition that affects several body systems, particularly the immune system. Recurrent infections are common in people with this condition. Affected individuals tend to have frequent bouts of pneumonia, which are caused by certain kinds of bacteria that infect the lungs and cause inflammation. These infections often result in the formation of air-filled cysts (pneumatoceles) in the lungs. Recurrent skin infections and an inflammatory skin disorder called eczema are also very common in AD-HIES. These skin problems cause rashes, blisters, accumulations of pus (abscesses), open sores, and scaling. AD-HIES is characterized by abnormally high levels of an immune system protein called immunoglobulin E (IgE) in the blood. IgE normally triggers an immune response against foreign invaders in the body, particularly parasitic worms, and plays a role in allergies. It is unclear why people with AD-HIES have such high levels of IgE. Credit: Genetic Home Reference.

Autosomal Recessive Agammaglobulinemia is similar to the primary immunodeficiency X-LA (X-Linked Agammaglobulinemia). X-LA is an X-linked disorder, meaning only males are affected. Immunologists have found a condition similar to X-LA in females, so they referred to it as autosomal recessive agammaglobulinemia. Due to the lack of antibodies, individuals with ARA are prone to infections, especially of the middle ear (otitis), sinuses (sinusitis), and lungs (pneumonia, bronchitis). Individuals with ARA can also experience gastrointestinal infections, skin infections, and possibly infections that can involve the bloodstream or internal organs. There is no way to cure individuals who have agammaglobulinemia. They can be treated through intravenous or subcutaneous immunoglobulin transfusion. The immunoglobulin will supply them with more antibodies, and help them fight off infections. Credits: Immune Deficiency Foundation, Genetics Home Reference