Summary
Definition
History and exam
Key diagnostic factors
- presence of risk factors
- recurrent and unusually severe infections
- chronic diarrhoea
- failure to thrive
- absent lymphoid tissue
Other diagnostic factors
- rash
- oral or genital ulcers
- microcephaly
- skeletal abnormalities
- blindness
- dystonia
- radiation sensitivity
Risk factors
- Family history of SCID
- Family history of infant death
- Athabascan-speaking Native American people
- Consanguinity
Diagnostic investigations
1st investigations to order
- FBC
- flow cytometry
- chest x-ray
- quantitative immunoglobulin test (IgG, IgM, and IgA)
Investigations to consider
- T-cell proliferation studies
- enzyme testing
- serum uric acid
- MRI chest
- chest ultrasound
- CT scan of the chest
- genetic testing
- radiation sensitivity of fibroblast cultures
- polymerase chain reaction-based viraemia testing
- fundoscopy
Treatment algorithm
confirmed SCID
Contributors
Authors
Javier Chinen, MD, PhD
Associate Professor
Pediatrics, Allergy, and Immunology
Baylor College of Medicine
Texas Children’s Hospital
Houston
TX
Disclosures
JC declares that he has no competing interests.
Acknowledgements
Dr Chinen would like to gratefully acknowledge Dr John M. Cunningham, Dr James L. LaBelle, Dr John Routes, Dr James Verbsky, Dr Nicole Chase, and Dr Ebrahim Shakir, the previous contributors to this topic. JLL, JR, JV, and NC are authors of references cited in this topic. JMC and ES declare that they have no competing interests.
Peer reviewers
Kathleen Sullivan, MD, PhD (CHOP)
Professor of Pediatrics
University of Pennsylvania
Chief
Division of Allergy and Immunology
Children's Hospital of Philadelphia
Philadelphia
PA
Disclosures
KS declares that she has no competing interests.
Charles Kirkpatrick, MD (UCHSC)
Professor of Medicine
Director
Adult Immunodeficiency Program
University of Colorado Denver
Aurora
CO
Disclosures
CK is an author of a reference cited in this topic. CK has received speaker fees from Cention, Aventis Behring, and Bristol Myers Squibb. CK has received honorarium for speaking at the Aspen Allergy Conference, for the Colorado Allergy Society. CK ran the research program for a biotechnology company with an approximate budget of $3.5 million.
Waseem Qasim, BMedSci (Hons), MBBS, MRCP (UK), MRCPCH, PhD
Senior Lecturer
Institute of Child Health
Consultant in Paediatric Immunology & Bone Marrow Transplantation
Great Ormond Street Hospital
London
UK
Disclosures
WQ declares that he has no competing interests.
Differentials
- 22q11.2 Microdeletion syndrome/DiGeorge syndrome
- Omenn's syndrome
- Zeta chain-associated protein 70 deficiency
More DifferentialsGuidelines
- Strimvelis for treating adenosine deaminase deficiency-severe combined immunodeficiency
- Recommendations for screening and management of late effects in patients with severe combined immunodeficiency after allogenic hematopoietic cell transplantation
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