CGD

Chronic Granulomatous Disease (CGD) is a rare, inherited immunodeficiency disorder that affects the immune system. Individuals with CGD have white blood cells that cannot effectively protect the body from certain types of bacteria and fungi. This condition is characterized by the formation of granulomas, which are clusters of immune cells that form in an attempt to wall off and contain the infection, but can also cause damage to tissues.

Causes

CGD is caused by mutations in any one of five genes that are involved in the production of an enzyme complex known as NADPH oxidase. This enzyme complex plays a crucial role in the immune system's ability to produce reactive oxygen species (ROS), which are used to kill invading pathogens. The mutations lead to either a partial or total lack of NADPH oxidase activity, which results in the immune system's inability to effectively kill certain bacteria and fungi.

Symptoms

The symptoms of CGD can vary widely among affected individuals but often include recurrent infections, such as pneumonia, abscesses, and infections of the skin or lymph nodes. These infections are often caused by organisms that are usually not harmful to people with normal immune systems. In addition to infections, individuals with CGD may also develop granulomas in various organs, which can cause further complications such as obstruction of the gastrointestinal or urinary tracts.

Diagnosis

Diagnosis of CGD typically involves a combination of clinical evaluation, family history, and specialized laboratory tests. One key diagnostic test is the dihydrorhodamine 123 (DHR) flow cytometry test, which can assess the ability of the patient's white blood cells to produce reactive oxygen species. Genetic testing can also be used to identify specific mutations in the genes responsible for CGD.

Treatment

Treatment for CGD focuses on preventing and treating infections, as well as managing complications. Prophylactic (preventive) use of antibiotics and antifungal medications is common, and interferon-gamma therapy has been shown to reduce the frequency of infections in some individuals. Bone marrow or stem cell transplantation may offer a potential cure for CGD, but it carries significant risks and is not suitable for all patients.

Prognosis

The prognosis for individuals with CGD has improved significantly with advances in treatment and management of the condition. However, life expectancy can still be reduced, and the quality of life can be affected by frequent infections and hospitalizations. Ongoing research into gene therapy and other novel treatments offers hope for improved outcomes in the future.