Chronic granulomatous disease (CGD)

Definition

Chronic granulomatous disease (CGD) is a rare genetic disorder that affects the immune system, specifically impairing the ability of phagocytes to kill certain types of bacteria and fungi. Individuals with CGD have a defective enzyme called NADPH oxidase, which is essential for producing reactive oxygen species needed to destroy pathogens. As a result, patients experience recurrent infections and form granulomas, which are clusters of immune cells that accumulate at infection sites, leading to various complications.

5 Must Know Facts For Your Next Test

1. CGD is primarily caused by mutations in the genes that code for components of the NADPH oxidase complex, leading to dysfunctional immune response.
2. Patients with CGD are particularly susceptible to infections from catalase-positive organisms such as Staphylococcus aureus and Aspergillus species.
3. Symptoms of CGD can include frequent bacterial infections, abscesses, and pneumonia, as well as chronic inflammation and tissue damage.
4. Management of CGD often involves prophylactic antibiotics and antifungal medications to prevent infections, as well as treatments like interferon-gamma to boost immune function.
5. Some patients with CGD may benefit from bone marrow or stem cell transplants as a potential curative treatment option.

Review Questions

• How does the defect in NADPH oxidase contribute to the symptoms observed in individuals with Chronic granulomatous disease?
  • The defect in NADPH oxidase prevents phagocytes from producing reactive oxygen species that are essential for killing certain bacteria and fungi. Without these reactive molecules, individuals with Chronic granulomatous disease are unable to effectively eliminate catalase-positive organisms, leading to recurrent infections. Additionally, the immune system responds by forming granulomas around these pathogens, resulting in inflammation and further complications.
• What role do granulomas play in the pathology of Chronic granulomatous disease and how might they affect overall health?
  • Granulomas form as a result of the immune system's attempt to isolate and contain pathogens that it cannot effectively destroy due to the NADPH oxidase defect. While this is a protective mechanism, excessive or chronic formation of granulomas can lead to tissue damage and disrupt normal organ function. This ongoing inflammation can cause symptoms such as pain, swelling, and impaired organ performance, impacting the overall health and quality of life for individuals with Chronic granulomatous disease.
• Evaluate the implications of Chronic granulomatous disease on patient management strategies and potential treatment options available.
  • Managing Chronic granulomatous disease involves a multifaceted approach aimed at preventing infections and addressing the underlying immune deficiency. Prophylactic antibiotics and antifungals play a crucial role in reducing infection rates, while therapies like interferon-gamma can enhance immune function. In severe cases where conventional treatments are insufficient, bone marrow or stem cell transplantation may offer a curative option. Understanding these management strategies is vital for improving outcomes and quality of life for patients living with this genetic disorder.

Related terms

Phagocytes: A type of immune cell that engulfs and digests foreign particles, bacteria, and dead or dying cells.

NADPH oxidase: An enzyme complex responsible for producing reactive oxygen species in phagocytes, crucial for killing pathogens.

Granuloma: A small area of inflammation in tissue formed by a collection of immune cells, often seen in chronic inflammatory conditions.