SEVERE COMBINED IMMUNODEFICIENCY - CHILDHOOD

Pediatric Severe Combined Immunodeficiency; X-Linked SCID; Adenosine Deaminase Deficiency; ADA-SCID; Classical X-linked SCID; Bubble Boy Disease

Severe Combined Immunodeficiency (SCID) is a life-threatening syndrome of recurrent infections, chronic diarrhea, dermatitis, and failure to thrive (FTT). SCID is an inherited immune system disorder characterized by defects in T-cells, B-cells, and sometimes natural killer (NK) cells. Although there are multiple genetic mutations that may result in various immune deficiencies, the childhood form of SCID is by far the most severe.

Diagnostic testing:

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  Lymphocyte function tests;

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  B-cell, T cell, and NK cell levels;

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  Immunoglobin levels (IgG, IgM, IgA, IgE); and

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  Genetic testing to identify the specific mutation(s) resulting in the immunodeficiency.

Physical findings: Infants and children with SCID have:

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  Recurrent, severe infections (respiratory, meningitis, sepsis);

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  Rashes that look like eczema;

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  Chronic diarrhea;

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  Oral thrush; and

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  Failure to thrive (FTT).

ICD-9: 279.2

SCID usually presents within the first few months of life with failure to thrive, recurrent and hard to treat severe infections (pneumonia, gastrointestinal infections, sepsis), recurrent or persistent thrush, chronic diarrhea, and absent lymph nodes. Without immune reconstitution treatment such as bone marrow transplantation, children with SCID generally die before age 3.

Children with SCID may be treated with antimicrobial prophylaxis, immunoglobulin replacement, and gene therapy. Transplantation of stem cell/bone marrow is the most effective treatment. Standard care for children with SCID includes isolation to avoid infection and meticulous skin and mucosal hygienic care while immune reconstitution.

SUGGESTED PROGRAMMATIC ASSESSMENT*

Suggested MER for Evaluation:

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  Clinical history and examination that describes the diagnostic features of the impairment and laboratory findings (see above) are needed to confirm the diagnosis; and

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  Documentation of bone marrow/stem cell transplantation.

Suggested Listings for Evaluation:

REMARKS

If received transplant, follow guidance of 114.07 B.