Immunity Flashcards
What are the hallmarks immune deficiency?
- serious infections
- persistent infections
- unusual infections
- recurrent infections
What are secondary immunodeficiency disorders?
common, subtle, involve more than one component of the immune system
What are the associated conditions to secondary immunodeficiency disorders?
HIV, immunosuppressive therapy, chemotherapy, cancers of the immune system and malnutrition
What are the common upper respiratory complications?
sinusitis, otitis media or laryngeal angioedema
What are the common lower respiratory complications?
malignancies, ILDs, pneumonia, bronchitis or bronchiectasis
What are the four ways that the cycle of a neutrophil can go wrong?
1- neutrophil development (leading to severe congenital neutropenia)
2- neutrophil trans endothelial migration (leads to recurrent infections, high neutrophil counts in the blood due to leukocyte adhesion deficiency)
3- neutrophil phagocytosis and killing (eg chronic granulomatous disease where free radical can’t be generated)
4- defects in macrophage killing (intracellular bacteria)
What is the treatment for phagocyte deficiencies?
- immunoglobin replacement therapy
- aggressive management of infection using oral/IV antibiotics and antifungals or surgical drainage of abscesses
- definitive therapy so stem cell transplants or gene therapy
What are the four ways that there can be defects in leukocyte development?
- defects in hamatopoetic stem cells
- defects in lymphoid precursor cells
- defects in thymocyte development
- defects in B cell developments
What are the effects of having defects in hematopoetic stem cells?
there is disruption in the mitochondrial membrane potential so no leukocytes are made so this is fatal
What happens when there are defects in lymphoid precursor cells?
SCID can occur as the patient can’t produce leukocytes, the child will have many infections and it is treated prophylactically (avoid infections and aggressive treatment of infections) and definitively (stem cell)
What is the result of defects in thymocyte development?
DiGeorge syndrome where there are no CD4+ (so no antibody so bacteria infections) or CD8+ (so viral infections) T cells and no CD4+ Th cells (fungal infections)
What is the result of defects in B cell development?
X-linked agammaglobulinaemia
What re the two ways that leukocyte effector functions can be defected?
- T cell effector functions (infections)
- B cell effector functions (hyper IgM syndrome and selective IgA deficiency)
What are the clinical features of T cell deficiencies?
- recurrent infections
- opportunistic infections
- malignancies at young age
- autoimmune disease
What are the clinical features of B cell deficiencies?
- recurrent infections
- opportunistic infections
- antibody-mediated autoimmune disease