Respiratory Flashcards
What organisms may cause phagocyte deficiencies?
Staph aureus, Burkhholderior cepacia, TB, fungi
How is incidence of severe infection after stem cell transplant related to number of circulating neutrophils?
indirectly proportionate
Despite all precautions, how many patients with a low neutrophil count will experience a severe infection post stem cell transplant?
1 in 4
Describe phagocyte deficiency in terms of neutrophils.
-Stem cells can fail to differentiate properly into neutrophils (Primary defect: recticular dysgenesis
Secondary defect: after stem cell transplantation
-Neutrophils can fail to mature
(Kostmann syndrome: severe congenital neutropaenia
or Cyclic neutropaenia
episodic neutropaenia every 4-6 weeks)
What type of disorder in Kostmann syndrome?
rare congenital autosomal recessive disorder
What growth factor can assist maturation of neutrophils?
Granulocyte colony stimulating factor (G-CSF
What causes Leukocyte adhesion deficiency and what does it result in?
- genetic defect in leucocyte integrins (CD18)
- Results in failure of neutrophil adhesion and migration
What are Toll like receptors, Scavenger receptors and Lectin receptors?
pathogen recognition receptors
May pathogen recognition receptors exhibit genetic polymorphism?
Yes (mostly does not cause signifigant disease)
Do defects in opsonin tend to cause signifigant disease?
No
What is a functional defect of phagocytosis?
the defect is not in the phagocytes themselves but in other components of immune response
What is Chronic granulomatous disease?
Failure of oxidative killing mechanisms
May chronic granulomatous disease cause hepatosplenomegaly?
Yes
What investigation should be carried out for chronic granulomatous disease?
NBT (“nitroblue tetrazolium”) test
What infections are associated with gIFN receptor deficiency, IL12 deficiency and
IL12 receptor deficiency?
TB/Salmonella
Name an important side effect of anti-TNF therapy.
Reactivation of latent tuberculosis
In severe combined immunodeficiency, what protects the neonate in the first 3 months of life?
Maternal IgG
What is the mutation in X-linked SCID?
Mutation of component of IL2 Receptor
What does this describe: Failure of thymic development, results in T cell immunodeficiency (nowhere for the T cells to mature). Clinical signs: Congenital heart defects Cleft palate Hypocalcaemia secondary to hypoparathyroidism Developmental delay Psychiatric disorders Obssesive compulsive disorder schizophrenia
DiGeorge Syndrome
What is the deletion in DiGeorge Syndrome?
Deletion at 22q11
What first line investigations should be carried out for T cell deficiencies?
Total white cell count and differential
Serum immunoglobulins and protein electrophoresis
Surrogate marker of functional T cells
Quantitation of lymphocyte subpopulations
Are lymphocyte counts generally higher in children or in adults?
children
What are the first line investigations for B cell deficiencies?
Total white cell count and differential
Serum immunoglobulins
Serum and urine protein electrophoresis
