How is T-B+ severe combined immunodeficiency diagnosed?

Information about diagnosis is currently limited for this condition.

Are there treatments for T-B+ severe combined immunodeficiency?

Information about treatment is currently limited for this condition.

What complications can arise from T-B+ severe combined immunodeficiency?

People with T-B+ severe combined immunodeficiency can face serious complications due to their weakened immune system. They are at a higher risk for repeated infections from viruses, bacteria, and fungi. These infections can lead to severe health issues and may require hospitalization.

How does T-B+ severe combined immunodeficiency affect daily life?

Living with T-B+ severe combined immunodeficiency can be challenging. People may need to take extra precautions to avoid infections, such as staying away from crowded places and practicing good hygiene. Additionally, they may require regular medical check-ups and treatments to manage their health.

What is the prognosis for someone with T-B+ severe combined immunodeficiency?

Information about the prognosis for T-B+ severe combined immunodeficiency is currently limited. However, the condition can lead to serious infections that may affect overall health. Early diagnosis and management are important for improving outcomes.

Are there any specific specialists recommended for managing T-B+ severe combined immunodeficiency?

While specific recommendations for specialists are not detailed, individuals with T-B+ severe combined immunodeficiency typically benefit from seeing immunologists. These doctors specialize in the immune system and can help manage the condition and any related health issues.

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T-B+ severe combined immunodeficiency - Clinical Profile, Genes & Research | Kisho | Kisho

Rare Disease

T-B+ severe combined immunodeficiency

MONDO:0044200

Also known as:T-B+ SCIDT-cell negative B-cell positive SCID

Overview

T-B+ severe combined immunodeficiency (SCID) is a group of rare monogenic primary immunodeficiency disorders characterized by a lack of functional peripheral T lymphocytes with presence of B lymphocytes, resulting in early-onset severe respiratory viral, bacterial or fungal infections, diarrhea and failure to thrive.

OnsetINFANTILE

Clinical Presentation

Built from Human Phenotype Ontology (HPO) phenotype annotations and GeneReviews clinical descriptions. Features represent findings documented across known cases — not an exhaustive list of possible symptoms.

No HPO annotations are available for this condition.

Age of onset: infancy.

GeneReviews

Clinical Guidance

X-linked severe combined immunodeficiency (X-SCID) comprises a phenotypic spectrum ranging from typical X-SCID (early-onset disease that is fatal if not treated with HSCT) to atypical X-SCID (later-onset disease comprising phenotypes caused by variable immunodeficiency, immune dysregulation, and/or autoimmunity).

Diagnosis

Drawn from GeneReviews diagnostic guidelines, newborn screening panel status (RUSP), and ClinGen gene-disease validity classifications. Reflects current clinical evidence and consensus where available.

GeneReviews

Diagnostic Criteria

The Primary Immune Deficiency Treatment Consortium (PIDTC) has established laboratory-based definitions for SCID . Infants with typical SCID have 300 autologous T cells per L, absent nave T cells, and poor proliferative responses to the mitogen phytohemagglutinin (10% of control values). Engraftment of maternal cells needs to be tested and excluded. Infants can also have hypomorphic SCID-related gene variants that allow residual function and produce an atypical phenotype (also known as "leaky" SCID) often with 1500 T cells per L.

Suggestive Findings

There are two scenarios in which X-SCID may be considered: an abnormal SCID newborn screening and a symptomatic male with suggestive findings. Both scenarios warrant immediate subspecialty immunologic evaluation and steps taken to ensure the safe...

Treatment

Compiled from FDA-approved drug records, orphan drug designations, and FDA Adverse Event Reporting System (FAERS) safety data. GeneReviews management guidance is included where available.

No approved treatments are currently available for T-B+ severe combined immunodeficiency. The disease remains an area of unmet medical need.

GeneReviews

Management Guidelines

Management is discussed in three subsections: issues relating to , those relating to , and those for .

Typical X-SCID Clinical Phenotype

Clinical practices and protocols for typical X-linked severe combined immunodeficiency (X-SCID) can vary depending on the center; however, many aspects overlap in an effort to minimize infection and maximize pre-hematopoietic stem cell transplantation (HSCT) management in infants with abnormal newborn screening results. The following outlines management based on the Primary Immune Deficiency Treatment Consortium (PIDTC) analysis .

Prognosis

Based on GeneReviews surveillance recommendations, HPO phenotype frequency and severity annotations, and published prevalence estimates from Orphanet and OMIM.

GeneReviews

Surveillance Guidelines

After successful HSCT, routine evaluation of affected males every six to 12 months is indicated to monitor lineage specific donor cell engraftment, growth, immune and lung function, and gastrointestinal and dermatologic issues. If conditioning chemotherapy was used, long-term monitoring of vital organ function and neurodevelopmental progress is also warranted.

Source: GeneReviews — "X-Linked Severe Combined Immunodeficiency"

Research Landscape

Sourced from ClinicalTrials.gov and PubMed. Publication types are classified using NLM-curated article metadata; research type breakdowns reflect the nature of published work for this disease.

No clinical trials have been registered for T-B+ severe combined immunodeficiency.

16 publications have been identified in PubMed for T-B+ severe combined immunodeficiency. Research spans Case Report / Case Series (31%), Basic Science / Preclinical (31%), and Gene Therapy / Novel Therapeutics (19%).

Research Type	Count	% of Total
Patient case studies	5	31%

Data assembled from 4 of 12 sources · Last updated Sep 20, 2026, 11:13 AM UTC

MONDOHPOClinicalTrials.govFDAPubMedHGNCClinVarClinGenGeneReviewsOrphanetOMIMRUSP

Medical References

External Resources

Orphanet

European rare disease database

Orphanet:317416

GARD

Genetic and Rare Diseases Info Center

GARD:21405

Questions for Your Care Team

→Are there specialists or centers of excellence for this condition in my area?
→Is there a patient registry I should consider joining?

FAQ

Frequently Asked Questions

Common questions about T-B+ severe combined immunodeficiency

T-B+ severe combined immunodeficiency (SCID) is a group of rare disorders that affect the immune system. In this condition, there is a lack of functional T lymphocytes, which are a type of white blood cell that helps fight infections. At the same time, B lymphocytes are present, but the overall immune function is severely compromised. People with this condition can experience repeated, early-onset infections caused by viruses, bacteria, or fungi. They may also suffer from symptoms such as diarrhea and failure to thrive, meaning that they might not gain weight or grow as expected.

People with T-B+ severe combined immunodeficiency often have early-onset infections. These infections can be due to respiratory viruses, bacteria, or fungi. Other common signs include diarrhea and poor growth or failure to thrive.

This condition is described as a monogenic disorder, which means it is caused by a mutation in a single gene. The gene mutation affects the production or function of T lymphocytes, a key component of the immune system. Information about the exact genetic mutations or risk factors is currently limited for this condition. Associated genes include IL2RG, IL7R, LAT, JAK3, CORO1A.

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GeneReviews

Differential Diagnosis

Since the implementation of newborn screening the incidence of each genetic type of typical severe combined immunodeficiency (SCID) has become clearer. X-SCID has remained one of the most common forms of typical SCID . summarizes genes known to be associated with typical SCID. Table 3. Typical Severe Combined Immunodeficiency: Genetic Causes

Gene(s)	Disorder	MOI	Lymphocyte Phenotype	Comments	NBS
T	B	NK Types of typical SCID w/identical clinical presentations	—	—	—
IL2RG	X-SCID (topic of this chapter; incl for comparison)	XL	–	+	–
JAK3	JAK3-SCID (OMIM 600802)	AR	–	+	–
IL7R	IL7R-SCID (OMIM 608971)	AR	–	+	+
Adenosine deaminase deficiency	AR	–	–	–	Delayed SCID if ADA deficiency is partial3
AK2	Reticular dysgenesis (OMIM 267500)	AR	–	–	–
CD3DCD3ECD247(CD3Z)	TCR deficiency (OMIM 615617, 615615, 610163)	AR	–/Low	+	+
CORO1A	CORO1A deficiency (OMIM 615401)	AR	–/Low	+/–	+/–
DCLRE1C	SCID Athabaskan (OMIM 602450)	AR	–	–	+
PRKDC	DNAPKCS deficiency (OMIM 615966)	AR	–	–	+
PTPRC(CD45)	CD45 deficiency (OMIM 608971)	AR	–	+	+/–
RAG2	RAG-deficient SCID (OMIM 601457)	AR	–	–	+

Source: GeneReviews — "X-Linked Severe Combined Immunodeficiency"

Kisho

T-B+ severe combined immunodeficiency

Overview

Clinical Presentation

Clinical Guidance

Diagnosis

Diagnostic Criteria

Suggestive Findings

Treatment

Management Guidelines

Typical X-SCID Clinical Phenotype

Prognosis

Surveillance Guidelines

Research Landscape

Medical References

External Resources

Orphanet

GARD

Questions for Your Care Team

Questions for Your Care Team

FAQ

Frequently Asked Questions

Differential Diagnosis

Evaluations Following Initial Diagnosis

Clinical Guidance

Therapies Under Investigation

Clinical Trials

Recent Publications

T-B+ severe combined immunodeficiency

Overview

Clinical Presentation

Clinical Guidance

Diagnosis

Diagnostic Criteria

Suggestive Findings

Treatment

Management Guidelines

Typical X-SCID Clinical Phenotype

Prognosis

Surveillance Guidelines

Research Landscape

Medical References

External Resources

Orphanet

GARD

Related Diseases

Questions for Your Care Team

Questions for Your Care Team

FAQ

Frequently Asked Questions

What is T-B+ severe combined immunodeficiency?

What are the symptoms of T-B+ severe combined immunodeficiency?

What causes T-B+ severe combined immunodeficiency?

How is T-B+ severe combined immunodeficiency diagnosed?

Are there treatments for T-B+ severe combined immunodeficiency?

What complications can arise from T-B+ severe combined immunodeficiency?

How does T-B+ severe combined immunodeficiency affect daily life?

What is the prognosis for someone with T-B+ severe combined immunodeficiency?

Are there any specific specialists recommended for managing T-B+ severe combined immunodeficiency?

Differential Diagnosis

Evaluations Following Initial Diagnosis

Clinical Guidance

Therapies Under Investigation

Clinical Trials

Recent Publications