The Special Problems of Congenital and Acquired Immunodeficiency
The number of immunodeficiencies is large, and the diagnosis and management of many of these conditions requires the expertise of a specialist pediatric immunologist (Box 7). Many immunodeficiencies, however, are seen first by a pediatric pulmonologist. The clinical picture and simple tests may indicate the presence of an underlying immunodeficiency. The acronym “SPUR” was introduced in the opening section of this article. Additional pointers to immunodeficiency include hepatosplenomegaly, arthropathy, failure to thrive, and a family history of immunodeficiency.
Box 7. Important congenital and acquired immunodeficiencies that may have a respiratory presentation
Congenital immunodeficiencies
Antibody deficiency
X-linked
Common variable immunodeficiency
IgA deficiency (not invariably significant)
Hyper IgM (CD40 deficiency)
IgG subclass deficiency (may be insignificant)
Complement disorders
C3 deficiency
Mannose-binding lectin deficiency
Neutrophil disorders
Autoimmune neutropenia of infancy
Cyclical neutropenia
Shwachman-Diamond syndrome
Kostman syndrome
Chronic granulomatous disease
Other syndromes
Di George syndrome (T-cell deficiency)
Down syndrome
Heterotaxic syndromes with asplenia (right isomerism, Ivemark's syndrome)
Ataxia telangiectasia
Wiskott-Aldrich syndrome
Hyper-IgE (STAT-3 mutations)
Interferon gamma receptor mutations (suspect if disseminated mycobacterial disease)
Interleukin-12 pathway mutations (suspect if disseminated mycobacterial disease)
Acquired
Infective
HIV
Iatrogenic
Steroids or immunosuppressant medication
Postradiotherapy
Post bone marrow and solid organ transplantation
Malignancy (often also associated with iatrogenic)
Leukemia and lymphoma
Solid organ
Miscellaneous
Acquired hyposplenism (trauma, sickle cell anemia)
Malnutrition of any cause
Chronic renal or liver failure
Diabetes
Burns
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