A plain-language guide

common variable immunodeficiency

What's known, what's still uncertain, and what's actively debated, written plainly, and built only from published medical research.

Early map · 7 sourced statements Every statement names its source Updated 2026-08-04
Please read this first. This guide is a companion to your medical team, not a replacement, and it is not medical advice. Everything here is tied to published research. If something you expected is not here, it almost always means we have not mapped a source for it yet, not that it is unknown to medicine. common variable immunodeficiency is an early, growing map, so it will look incomplete on purpose: we would rather show less and have every line be something you can check than fill the page with claims we cannot stand behind. For anything about your own situation, your clinicians hold the full picture. How this guide is built and why.

What's common variable immunodeficiency?

Common variable immunodeficiency is the most common symptomatic inborn error of immunity in adults, a disorder of the immune system that leaves the body unable to fight infections normally.

Features mapped5
Treatments mapped1
Published sources5
Last reviewed2026-08-04

Signs and symptoms

Recurrent bacterial infections

People with CVID get frequent bacterial infections, especially of the lungs and airways such as pneumonia and bronchitis.

Limited evidenceSource: PMID:14550517
Evidence ratingweak
Study designontology_import
Confidence (0-1)0.7
Replicationunreplicated
Supporting sourcesPMID:41465777, OMIM:607594
Notesplain_language confirmed from PMID:41465777 via curation 2026-07-03 [llm:fable-5]. | regrounded primary OMIM:607594 -> PMID:14550517 on 2026-07-03 [Carrie Schluter, BCPA]
Last reviewed2026-07-03

Recurrent pneumonia

Recurrent bacterial pneumonia is common in CVID.

Limited evidenceSource: PMID:42278892
Evidence ratingweak
Study designontology_import
Confidence (0-1)0.7
Replicationunreplicated
Supporting sourcesPMID:41465777, OMIM:607594
Notesplain_language confirmed from PMID:41465777 via curation 2026-07-03 [llm:fable-5]. | regrounded primary OMIM:607594 -> PMID:42278892 on 2026-07-03 [Carrie Schluter, BCPA]
Last reviewed2026-07-03

Splenomegaly

The spleen can become enlarged (splenomegaly) in CVID.

Limited evidenceSource: PMID:41869311
Evidence ratingweak
Study designontology_import
Confidence (0-1)0.7
Replicationunreplicated
Supporting sourcesPMID:41324469, OMIM:607594
Notesplain_language confirmed from PMID:41324469 via curation 2026-07-03 [llm:fable-5]. | regrounded primary OMIM:607594 -> PMID:41869311 on 2026-07-03 [Carrie Schluter, BCPA]
Last reviewed2026-07-03

Bronchiectasis

Repeated lung infections in CVID can lead to bronchiectasis, permanent scarring and widening of the airways.

Limited evidenceSource: PMID:42227882
Evidence ratingweak
Study designontology_import
Confidence (0-1)0.7
Replicationunreplicated
Supporting sourcesPMID:41465777, OMIM:607594
Notesplain_language confirmed from PMID:41465777 via curation 2026-07-03 [llm:fable-5]. | regrounded primary OMIM:607594 -> PMID:42227882 on 2026-07-03 [Carrie Schluter, BCPA]
Last reviewed2026-07-03

Decreased circulating IgG concentration

The defining feature of CVID is low levels of immunoglobulins (antibodies) in the blood, known as hypogammaglobulinemia.

Limited evidenceCurated reference: OMIM:607594
Evidence ratingweak
Study designontology_import
Confidence (0-1)0.7
Replicationunreplicated
Supporting sourcesPMID:14550517
Notesplain_language confirmed from PMID:14550517 via curation 2026-07-03 [llm:fable-5].
Last reviewed2026-07-03

Treatment and management

What the research describes, not a recommendation. Treatment decisions belong with your clinician.

This covers treatments that appear in the published research mapped here. Investigational and experimental therapies are not included, so their absence is a boundary of this map, not a sign they do not exist.

immunoglobulin replacement therapy

Immunoglobulin replacement therapy is used in CVID and can help prevent infection flare-ups.

Used to help with: Recurrent bacterial infections.

Limited evidenceSource: PMID:42278892
The source text this rests on
“Early recognition of CVID and appropriate immunoglobulin replacement therapy can prevent infectious…”
An excerpt quoted verbatim from the source named above, shown as recorded. The full sentence is in the linked source.
Evidence ratingweak
Confidence (0-1)0.7
Replicationunreplicated
Notesconfirmed from PMID:42278892 via curation 2026-07-03
Last reviewed2026-07-03

How to read the evidence labels

Widely acceptedSpecialists broadly agree on this.
Strong evidenceBacked by solid, repeated research.
Moderate evidenceReasonable evidence, still being confirmed.
Limited evidenceSome evidence, but not yet convincing.
Early evidenceAn early finding that needs more study.
Experts disagreeResearchers actively disagree about this.
No longer supportedLater, stronger evidence or guidance overturned this.

Where this comes from

This guide is built from 5 published source(s). Every claim above links back to one of them. Click any source ID to read the original on PubMed.

OMIM:607594 · Orphanet/HPO annotations for Immunodeficiency, common variable, 1
PMID:14550517 · [Common variable immunodeficiency: 17 observations in the adult].
PMID:41869311 · Clinical and immunological differentiation of isolated IgG and combined IgG & IgM deficiencies from common variable immunodeficiency.
PMID:42227882 · Associations between disease factors and clinical outcomes in common variable immunodeficiency: a systematic literature review.
PMID:42278892 · Prolonged Infections and Inflammatory Diseases in Common Variable Immune Deficiency as a Cause of AA Amyloidosis.

Take it further

Printed, source-linked documents built from this condition's graph — ready to bring to an appointment or attach to a coverage request. Every claim carries its published source, the same as this guide.

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