Immunodeficiency due to a complement cascade component deficiency

Last reviewed

🖨 Print for my doctorAdvocacy Hub →
ORPHA:459345
Who is this for?
Show terms as
8Treatment centers

Where are you in your journey?

UniteRare data is sourced from FDA.gov, ClinicalTrials.gov, Orphanet, OMIM, and NORD.
Report missing data

Overview

Immunodeficiency due to a complement cascade component deficiency is a group of rare inherited conditions in which one or more proteins of the complement system are missing or do not work properly. The complement system is a set of about 30 proteins in the blood that work together as part of your immune defense. These proteins help your body fight infections by tagging bacteria and other germs for destruction, directly killing some germs, and helping clear dead cells. When one of these complement proteins is deficient, the immune system cannot fully protect the body. People with complement deficiencies are more prone to serious and recurrent bacterial infections, particularly those caused by encapsulated bacteria such as Neisseria meningitidis (which causes meningitis and sepsis), Streptococcus pneumoniae, and Haemophilus influenzae. Depending on which complement component is missing, some individuals may also develop autoimmune conditions such as systemic lupus erythematosus (SLE or lupus), kidney inflammation, or recurrent skin infections. Symptoms can range from mild to life-threatening. Treatment focuses on preventing and promptly treating infections. This includes vaccinations against common encapsulated bacteria, prophylactic antibiotics in some cases, and rapid antibiotic treatment when infections occur. There is no cure that replaces the missing complement protein on a long-term basis, though research continues. Early diagnosis and a strong prevention plan can significantly improve quality of life and reduce the risk of dangerous infections.

Key symptoms:

Recurrent bacterial infections, especially meningitisRepeated episodes of blood poisoning (sepsis)Frequent sinus infectionsRecurrent ear infectionsRecurrent pneumoniaSkin infections or abscessesLupus-like symptoms such as joint pain and skin rashesKidney inflammationSwelling episodes (in some types)Slow wound healingFatigue and general feeling of being unwellFever with no clear causeUnusual susceptibility to Neisseria infections (meningococcal disease)

Inheritance

Variable

Can be inherited in different ways depending on the underlying gene

Age of Onset

Variable

Can begin at different ages, from infancy through adulthood

Orphanet ↗NORD ↗

Treatments

No FDA-approved treatments are currently listed for Immunodeficiency due to a complement cascade component deficiency.

View clinical trials →

No actively recruiting trials found for Immunodeficiency due to a complement cascade component deficiency at this time.

New trials open frequently. Follow this disease to get notified.

Search ClinicalTrials.gov ↗Join the Immunodeficiency due to a complement cascade component deficiency community →

No specialists are currently listed for Immunodeficiency due to a complement cascade component deficiency.

View NORD Rare Disease Centers ↗Undiagnosed Disease Network ↗

Treatment Centers

8 centers
🏥 NORD

Baylor College of Medicine Rare Disease Center

Baylor College of Medicine

📍 Houston, TX

🏥 NORD

Stanford Medicine Rare Disease Center

Stanford Medicine

📍 Stanford, CA

🔬 UDN

NIH Clinical Center Undiagnosed Diseases Program

National Institutes of Health

📍 Bethesda, MD

🔬 UDN

UCLA UDN Clinical Site

UCLA Health

📍 Los Angeles, CA

🔬 UDN

Baylor College of Medicine UDN Clinical Site

Baylor College of Medicine

📍 Houston, TX

🔬 UDN

Harvard/MGH UDN Clinical Site

Massachusetts General Hospital

📍 Boston, MA

🏥 NORD

Mayo Clinic Center for Individualized Medicine

Mayo Clinic

📍 Rochester, MN

👤 Mayo Clinic Center for Individualized Medicine

🏥 NORD

UCLA Rare Disease Day Program

UCLA Health

📍 Los Angeles, CA

Travel Grants

No travel grants are currently matched to Immunodeficiency due to a complement cascade component deficiency.

Search all travel grants →NORD Financial Assistance ↗

Community

Open Immunodeficiency due to a complement cascade component deficiencyForum →

No community posts yet. Be the first to share your experience with Immunodeficiency due to a complement cascade component deficiency.

Start the conversation →

Latest news about Immunodeficiency due to a complement cascade component deficiency

No recent news articles for Immunodeficiency due to a complement cascade component deficiency.

Follow this condition to be notified when news becomes available.

Caregiver Resources

NORD Caregiver Resources

Support, advocacy, and financial assistance for caregivers of rare disease patients.

Mental Health Support

Rare disease caregiving can be isolating. Connect with counseling and peer support.

Family & Caregiver Grants

Financial assistance programs specifically for caregivers of rare disease patients.

Social Security Disability

Learn how rare disease patients may qualify for SSDI/SSI benefits.

Questions for your doctor

Bring these to your next appointment

  • Q1.Which specific complement component is deficient, and what does that mean for my risk of infections and autoimmune disease?,What vaccinations do I need, and how often should they be updated?,Should I take daily preventive antibiotics?,What are the warning signs that I should go to the emergency room immediately?,Should my family members be tested for this condition?,Are there any activities, travel destinations, or medications I should avoid?,What is the long-term outlook for someone with my specific complement deficiency?

Common questions about Immunodeficiency due to a complement cascade component deficiency

What is Immunodeficiency due to a complement cascade component deficiency?

Immunodeficiency due to a complement cascade component deficiency is a group of rare inherited conditions in which one or more proteins of the complement system are missing or do not work properly. The complement system is a set of about 30 proteins in the blood that work together as part of your immune defense. These proteins help your body fight infections by tagging bacteria and other germs for destruction, directly killing some germs, and helping clear dead cells. When one of these complement proteins is deficient, the immune system cannot fully protect the body. People with complement de