BLI 48-49 Flashcards
Which test should be performed on a patient with N. meningitidis?
CH50 or CH100
1 yo who just learned to walk presents with Ataxia-Telangiectasia. What is the presenation traid?
Cerebellar ataxia
Oculocutaneous telangiectasia
Humoral & cellular immunodeficiency (low IgE and IgA)
- leads to recurrent sinopulmonary infections
Also associated with leukemia and lymphoma
Presents with Hyper-IgM syndrome
Deficiency of IgG, IgA, IgE
X-linked disorder
What is the responsible cellular defect?
No CD40L on T-cells
Tx: IVIG
antibiotics
B cells don’t mature –> no mature B cells
Normal T cells
Low Ig
X-linked (Bruton) Agammaglobulinemia
Tx: IVIG
NO ORAL POLIO VACCINE
Which complement deficiency involves small immune complexes causing SLE-like syndrome
C1, C2, C4
What is the presentation triad of Wiskott-Aldrich Syndrome
WATER
- Wiskott
- Aldrich
- Thrombocytopenic purpura
- Eczema (atopic dermatitis)
- Recurrent infections (opportunistic & encapsulated)
X-linked disorder of platelets and WBCs
Presents in infancy
Wiskott-Aldrich Syndrome
Abnormal neutrophil function due to microtubule dysfunction affecting phagolysosome-lysosome fusion
Chediak-Higashi Syndrome
Infant presents with excessive bleeding after circumcision. What is the plan of vaccination for this patient?
Wiskott-Aldrich Syndrome
NO LIVE VACCINES
Due to defect in ATM kinase
- inability to assemble TCR & BCR
- inability to repair dsDNA damage
Ataxia-telangiectasia
Treatment for SCID
Stem cell transplant ASAP
NO LIVE VACCINES (MMR, varicella)
NO NON-IRRADIATED BLOOD
Defect in Btk tyrosine kinase
X-linked (Bruton) Agammaglobulinemia
Presents in 1st decade of life
Recurrent viral infections
Normal Ab production
Also called bare lymphocyte
MCH Class 1 Deficiency (Bare lymphocyte)
Mutation on TAP1
MCH Class 1 Deficiency (Bare lymphocyte)
Glycoprotein defect
No ligands for selectins
LAD II
Both SCID and Hyper-IgM present with increased risk for PCP infection. What sets them apart in terms of presentation?
SCID –> chronic diarrhea, failture to thrive
Hyper-IgM –> giardia, aplastic anemia (parvo), cervical LAD
CD8 T cells deficient
MCH Class 1 Deficiency (Bare lymphocyte)
Patient with Hyper-IgM syndrome is at risk for infections due to what organisms?
Encapsulated bacteria (also Brutons)
Giardia (also Brutons, CVID)
Pneumocystis jirovecii - PCP
Parvovirus –> aplastic anemia
Due to defect in cytoskeletal glycoprotein
Wiskott-Aldrich Syndrome
Patient presents with C1 esterase inhibitor deficiency
Inheritance and presentation?
Autosomal dominant
Hereditary angioedema (inflammation and edema due to Bradykinin)
- Deficiency causes inability to inhibit classical pathway
Patient presents with delayed separation of umbilical stump. Skin, mucosal, and respiratory infections do not contain pus.
Treatment?
Leukocyte Adhesion Deficiency
Tx –> stem cell transplant
What is the presentation of DiGeorge Syndrome?
CATCH22
- Cardiac anomalies
- Abnormal facies (short philtrum, hypotelorism, mandibular hypoplasia, low-set ears)
- Thymic aplasia
- Cleft palate
- Hypocalcemia
- 22nd chromosome deletion (22q11.2)
Presents in teenage years with non-caseating granulomas
Increased risk:
- autoimmune
- lymphoma
- bronchiectasis
- gastric CA
Common Variable Immunodeficiency
Treatment for DiGeorge Syndrome
Thymic tissue transplant
CD4 T cells are deficient
What is the underlying problem
MCH Class 2 Deficiency (Bare lymphocyte)
Defects in transcription factors fails to put MCH II on dendritic cells, macrophages, B lymphocytes
In SCID due to a defect in the cytokine receptor subunit gamma-c, which IL’s are responsible for:
- Lose lymphocyte development:
- Loose lymphocyte function:
Development: IL-7
Function: IL-2
The autosomal recessive form of SCID is due to what deficiency?
Adenosine deaminase deficiency
Most common B lymphocyte disorder
Presents > 4 yo with celiac disease
What other possible presentations?
IgA Deficiency
Asymptomatic
Airway + GI infections
Autoimmune disease
Atopy
Anaphylaxis to IgA
Labs shown decreased IgA, all other Ig NL
Immunodeficiency that is a pediatric emergency
SCID
Two tests to diagnosis chronic granulomatous disease
Nitroblue tetrazoium test (NBT)
- NL: Neutrophils turn from yellow to dark blue
Dihydrorhodamine assay (DHR)
- NL: increased fluorescence intensity in neutrophils
Which complement deficiency places patient at risk for severe recurrent infections with encapsulated bacteria
C3
Normal B cell development
Deficient B cell differentiation
Deficient in all types of Ig
Common Variable Immunodeficiency
Tx: IVIG
Infection specific tx
Inheritance and genetic defect of the most common type of SCID
X-linked
Defect in gamma-chain of IL-2 Receptor
Abnormal neutrophil function due to NADPH oxidase deficiency
Chronic granulomatous disease
Which type of immunity is affected by SCID
Humoral
Dysmorphogenesis of 3rd and 4th pharyngeal pouches
DiGeorge Syndrome (Thymic aplasia)
LFA-1 integrin (CD18) defect
LAD1
- no stable adhesion
Absence of CD18
LAD
Which type of SCID is responsible for the progressive accumulation of toxic purine metabolites?
SCID 2/2 Adenosine Deaminase Deficiency
Presents in infancy
Looks like SCID
Hypogammaglobulinemeia
Also called bare lymphocyte
MCH Class 2 Deficiency (Bare lymphocyte)
Abnormal migration of neutrophils into tissues - many neutrophils are seen in circulation
Leukocyte Adhesion Deficiency
>6 mo old presents with high IgG with delayed production of IgG at 6 months
Normal B & T cells
Normal response to DTap
What is the treatment?
Transient Hypogammaglobulinemia of Infancy
No treatment - levels will gradually increase between 2-4 yo
May give prophylactic antibiotics
Presents 6-12 months
Why
X-linked (Bruton) Agammaglobulinemia
Mother’s IgG protects until 6 mo
Patient presents with neutrophil dysfunction causing lack of NK cell activity, partial oculocutaneous albinism, and microscopy reveals giant granules.
Chediak-Higashi syndrome
Impaired ability to kill catalase-positive organisms
Chronic granulomatous disease
A deficiency in which two recombinase enzymes causes SCID?
RAG-1 & RAG-2
No development of TCR’s or Ig
Which complement deficiency causes an impairment in only MAC, and places patient at risk for infections with N. meningitidis
C5-C9
