inherited disorder of lymphocytes

Question 1

• have variable degrees of immunodeficiency because of the absence or decreased size of the thymus and low numbers of T lymphocytes
• Associated with a broad range of problems such as cardiac defects, palatal abnormalities, distinctive facial features, developmental delays, psychiatric disorders, short stature, kidney disease, and hypocalcemia
• Hematologic issues include thrombocytopenia and large platelets, autoimmune cytopenias, and increase risk of malignancy
• Deathrate is high usually before 1 year of age

EXAMPLES:
* Nezelof’s syndrome
* DiGeorge syndrome
* Autosomal dominant Opitz GBBB
* Sedlackova syndrome
* Caylor cardiofacial syndrome
* Shprintzen syndrome
* Conotruncal anomaly face syndrome

Answer 1

22q11 syndromes

Question 2

• Also called as X-linked agammaglobulinemia, Bruton’s agammaglobulinemia
• Is a primary immunodeficiency disease characterized by reductions in all serum immunoglobulin isotypes and profoundly decreased or absent B cells
• caused by a mutation in the gene encoding Bruton tyrosine kinase, resulting in decreased production of BTK, which is important for B cell development, differentiation, and signaling
• lymphocytes fail to fully mature, leading to severe hypogammaglobulinemia and an inability to produce specific antibodies
• Infants display symptoms between 4 and 6 months, once maternal antibodies have cleared.; recurring life-threatening bacterial infections ensue
• Risk of fungal and viral (except enterovirus) infection is low because of normal T cell function

Answer 2

bruton-tyrosine kinase deficiency

Question 3

ataxia telangiectasia

: progressive loss of muscle coordination

Answer 3

ataxia

Question 4

• Rare X-linked disease caused by one of more than 400 mutations in the WAS gene, which results in decreased levels of WASp protein
• important in cytoskeletal remodeling and nuclear transcription in hematopoietic cells
• Tcells are decreased; B cells, T cells and NK cells, neutrophils and monocytes are dysfunctional which leads to bacterial, viral and fungal infections
• Risk of bleeding due to thrombocytopenia and small abnormal platelets

Answer 4

wiskott-aldrich syndrome

Question 5

SCID

• A defect in the helper cellular immune mechanism leading to agammagloulinemia
• Defect is seen only in boys

Answer 5

sex-linked agammaglobulinemia

Question 6

SCID

• (?) represents 10% to 20% of SCID cases and is caused by one of many mutations in the ADA gene
• ADA deficiency results in an intra- and extracellular accumulation of (?), which is lymphotoxic, leading to profound decreases in (?), (?), and (?) cells
• Patients experience a range of recurring, life-threatening bacterial, viral, and fungal infections beginning early in life. In addition, there are skeletal abnormalities, neurologic deficits, and skin rashes

Answer 6

• autosomal recessive adenosine deaminase deficiency

adenosine

T, B, NK

Question 7

SCID

• Autosomal recessive; involves loss of both T-cell and B-cell functions
• Little or no immunoglobulin is found in the blood; thymus is present but lacks lymphoid elements

Answer 7

swiss-type agammaglobulinemia

Question 8

ataxia telangiectasia

: dilation of the small blood vessels

Answer 8

telangiectasia

Question 9

SCID

• (?), or (?), is the most common form of SCID and is caused by mutations in the IL2RG
  gene
• (?) normally codes for the common gamma chain in leukocyte receptors that bind with interleukins 2, 4, 7, 9,15 and 21 (provide growth, differentiation, and survival signals for B, T, and NK cells)
• Patients become symptomatic between (?) to (?) months of age as protective maternal immunoglobulins are depleted, presenting without tonsils or lymph nodes along with severe life-threatening recurring infections
• Circulating (?) and (?) lymphocytes are nearly absent; (?) are adequate in number but are dysfunctional
• Children with gamma chain deficiency fail to thrive and death usually occurs before age (?) unless treatment with hematopoietic stem cell transplant is successful

Answer 9

• gamma chain deficiency, X-linked SCID
• IL2RG
• 3, 6
• T, NK
• B cells
• 2

Question 10

• One or a combination of immunoglobulins is either missing entirely or is synthesized in small quantities
• Inability of B-cells to mature to plasma cells which can be excessive production of T-suppressor cells

Answer 10

common variable hypoglobulinemia

Question 11

SCID

• Autosomal recessive
• progressive loss of muscle coordination
• dilation of the small blood vessels
• Associated with peripheral blood lymphopenia, aplastic or hypoplastic thymus with minimal T-cell population
• Decreased IgA and IgE, normal to increased IgG

Answer 11

ataxia telangiectasia