Also known as Complement Deficiency, Immune Deficiency due to Complement Disorders
Summary
Defects in the complement system are a group of rare immunodeficiency disorders where components of the complement system—part of the body's immune defense—are missing or not functioning properly. This can lead to increased susceptibility to infections and autoimmune conditions.
Causes
Primarily caused by genetic mutations that affect complement proteins.
Deficiencies can be inherited (congenital) or, in some rare cases, acquired.
Risk Factors
Family history of immunodeficiency disorders.
Certain genetic backgrounds may predispose individuals to complement deficiencies.
Symptoms
Increased frequency and severity of bacterial infections, particularly with Neisseria species.
Symptoms of autoimmune diseases, such as systemic lupus erythematosus (SLE).
Recurrent respiratory infections.
Diagnosis
Blood tests to measure levels of complement proteins.
Genetic testing to identify specific mutations.
Functional assays to evaluate complement system activity.
Treatment Options
Antibiotic prophylaxis to prevent infections.
Immunizations to provide additional protection.
Plasma infusions or complement replacement therapies in certain cases.
Prognosis and Follow-Up
Prognosis varies depending on specific defects and their severity.
Regular monitoring and early treatment of infections are critical.
Life-long follow-up with an immunologist is often necessary.
Complications
Increased risk of severe and recurrent infections.
Development of autoimmune diseases if not properly managed.
Lifestyle & Prevention
Adherence to prescribed prophylactic antibiotics.
Staying up-to-date with vaccinations.
Prompt treatment of infections.
When to Seek Professional Help
Unusual frequency or severity of infections.
Symptoms of autoimmune disorders, such as joint pain or skin rashes.
Any sudden or severe illness, especially if accompanied by fever.