Immunodeficiencies Flashcards
Th1 cells fail to produce IFN-gamma –> inability of neutrophils to respond to chemotactic stimuli
Hyper-IgE Syndrome (Job’s Syndrome)
- Finding is increased IgE
Defective IL-2 (most common, X-linked), or Adenosine Deaminase Deficiency leads to decreased T-cell recombinant excision circles (TRECs), absence of thymic shadow/germinal centers/T-cells
Severed Combined Immunodeficiency (SCID)
Findings include decreased IgA with normal IgG, IgM, and IgG vaccine titers with False-positive Beta-HCG due to presence of heterophile antibody
Selectie IgA Deficiency
Defect in LFA-1 Integrin (CD18) protein on phagocytes found with neutrophilia
Leukocyte adhesion deficiency (type I)
Most Common Primary Immunodeficiency that is typically asymptomatic but can have Anaphylaxis to IgA-containing blood products
Selective IgA Deficiency
Defect in B-cell Maturation that can be acquired in 20s-30s with increased risk of autoimmune disease, lymphoma, and sinopulmonary infections
Common Variable Immunodeficiency (CVID)
Findings include absent thymic shadow on CXR, decreased T cells, decreased PTH, and decreased Ca 2+
Thymic Aplasia (DiGeorge Syndrome)
Decreased Th1 response present with disseminated mycobacterial infections and decreased IFN-gamma
IL-12 Receptor Deficiency
Presentation includes FATED: coarse Facies, cold (non inflamed), staphylococcal Abscesses, retained primary Teeth, increased IgE, Dermatologic problems (eczema)
Hyper-IgE Syndrome (Job’s Syndrome)
T-cell Dysfunction that presents with Candida Albicans infections of skin and mucous membranes
Chronic Mucocutaneous Candidiasis
Presents with Failure to Thrive, chronic diarrhea (diaper rash), thrush, recurrent viral/bacterial/fungal infection, absence of thymic shadow/germinal centers/B cells
Severe Combined Immunodeficiency (SCID)
Findings are Normal Pro-B, Decreased Maturation, Decreased # of B cells, Decreased Immunoglobulins of all classes
- X-linked (Bruton’s) Agammaglobulinemia
Presents with Recurrent pyogenic infections by staph and strep; partial albinism, and peripheral neuropathy
Chediak-Higashi Syndrome
Defects in the ATM gene which codes for DNA repair enzymes and increases AFP
Ataxia-Telangiectasia
- X-linked recessive Defect in BTK, a tyrosine kinase gene that presents with recurrent bacterial, enterovirus (polio and coxsackievirus) and Giardia Lamblia infections after six months.
- X-Linked (Bruton’s) Agammaglobulinemia
- leads to NO B cell maturation
Presents with Cerebellar Defects (ataxia), spider angiomas (telangiectasia), and IgA deficiency
Ataxia-Telangiectasia
CD40 Ligand Defect on helper T cells –> inability to class switch
Hyper-IgM Syndrome
X-linked defect in WAS gene on X chromosome –> T cells unable to reorganize actin cytoskeleton
Wiskott-Aldrich Syndrome
Presents with Thombocytopenic Purpura, Infections, Eczema
Wiskott-Aldrich Syndrome
Presents with recurrent bacterial infections, absent pus formation, and delayed umbilical cord separation
Leukocyte adhesion deficiency (type I)
Lack of NADPH oxidase –> decreased ROS (superoxide) and absent resp burst in neutrophils presents with increased susceptibility to catalase-pos organisms (S. aureus, E.coli, and Aspergillus)
Chronic Granulomatous Disease
Autosomal recessive defect in lysosoal trafficking regulator gene (LYST) –> microtubule dysfunction in phagosome-lysosome fusion found with Giant Granules in Neutrophils
Chediak-Higashi Syndrome
Test for Chronic Granulomatous Disease
Abnormal Dihydrorhodamine (DHR) flow cytometry test - Nitroblue tetrazolium dye reduction test no longer preferred.
Findings include Increased IgE and IgA with decreased IgM, Thrombocytopenia
Wiskott-Alrich Syndrome
22q11 Deletion; Failure to develop 3rd and 4th pharyngeal pouches that presents with Tetany (hypocalcemia), recurrent viral/fungal infections, congenital heart and great vessel defects
Thymic Aplasia (DiGeorge Syndrome
Findings include Increased IgM with decreased IgG, IgA, and IgE and presents with severe pyogenic infections early in life
Hyper-IgM Syndrome
