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  • Understand Primary Immunodeficiency and its warning signs. Connect with expert immunologists.
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About Primary Immunodeficiency

Primary Immunodeficiencies (PIs) are a group of 524 disorders of the immune system with varying degrees of severity. They occur when one or more essential parts of the immune system do not work correctly. PIs are also referred to as Inborn Errors of Immunity (IEIs).

IUIS 2024 Classification of Inborn Errors of Immunity

The International Union of Immunological Societies (IUIS) Expert Committee maintains the definitive classification of human inborn errors of immunity. Explore the complete hierarchical classification below, organized into 9 major categories.

525 disorders classified across 9 major categories
Click on any segment to zoom in and explore the hierarchy


Explore the Data from Different Perspectives

Genes (circles)
Disorders (squares)
Drag nodes to reposition. Click to focus on connections.

Category × Inheritance Mode Relationships

Chord diagram showing how 524 disorders are distributed across 9 IUIS categories and 7 inheritance patterns. Click on chords to explore specific combinations.

Categories (1-9)

<p>Bone marrow failure with immune deficiency</p>.

Inheritance Modes

Autosomal Recessive
Autosomal Dominant
X-Linked
AD (haploinsufficiency)
AD DN (dominant negative)
AD GOF
AD LOF (dominant negative)
AR (LOF/GOF)
AR LOF
AR or AD
Sporadic
Variable
XL (Biallelic mutations in pseudo- autosomal gene)
XL (females may be affected)
XL GOF


Loading heatmap...


Gene → Category → Manifestation Flow

Sankey diagram showing how genes flow through IUIS categories to produce clinical manifestations. Flow width represents disorder count.

Flow Structure

Genes (left column)
IUIS Categories (middle column)
Clinical Manifestations (right column)
Link thickness represents the number of disorders in that flow path.

The Immune System

It’s our only defense... but it doesn’t work for everyone. Each and every day, your body fights off infections, germs, bacteria, and viruses. These invaders, called pathogens, are destroyed by the body’s number one defense, the immune system. Some people are born with immune systems that don’t work as well as others. This could be due to Primary Immunodeficiency, which might cause a person to be sick more often than others.

People with Primary Immunodeficiency cannot get rid of pathogens or protect themselves from these pathogens as well as they should, causing frequent infections and other problems that are hard to cure. Infections may appear to be common illnesses such as sinus and ear infections, pneumonia, fever, common colds, and bronchitis.

Why Getting Help Is Important

Today patients with Primary Immunodeficiency are able to gain and maintain control of their lives with treatment and intervention:

  • They are able to participate in work, school, family, and social activities.
  • They have fewer and less severe infections.
  • They feel good about their treatment programs and, most importantly, themselves.

Failure to diagnose Primary Immunodeficiency can lead to an increased number and severity of infections, frequent interruptions in work, school, family, and social activities, and a lifetime of serious illness, including permanent organ damage. There are many treatment options that can help patients diagnosed with Primary Immunodeficiency lead healthier lives.

  • Find Expert Immunologists
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In 2024, The Jeffrey Modell Foundation received the highest four-star rating from Charity Navigator for the 9th consecutive year, ranking #1 in Immunology out of 10,000 organizations evaluated worldwide.

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