Immunology Flashcards
Pathophysiology:
What hypersensitivity reaction is urticaria?
Type 1 hypersensitivity
Pathophysiology:
How does acute urticaria present?
Raised, pruritic, erythematous plaques with a rapid onset hypersensitivity (type 1)
Pathophysiology:
What cells are activated in a type 1 hypersensitivity reaction?
Mast cells
Immunology:
What are opsonins?
Immune system components that coat the surface of batters, tagging them for phagocytosis
Immunology: Immunology
Which opsonins are the most important?
What is the consequence of not having them?
- IgG and C3b
- without them bacteria can evade the immune system via negatively charged repulsion and ppl are more prone to bacteria with a polysaccharide capsule, including S. Pneumoniae, N. Meningitidis, and S. Typhi
Immunology: Pharmacology
What are the adverse effects of diphenhydramine?
6 points
- Orthostatic hypotension (PF)
- urinary retention
- dry mouth
- CNS depression
- dizziness
- delirium
Immunology: Immunology
What is the inheritance for ADA deficiency type of SCID?
Autosomal recessive
Pathophysiology:
What is the role of excessive Th2 activity in the case asthma?
Stimulates eosinophils to promote remodeling and hypersensitivity in the lungs
Immunology Pharmacology:
What receptors are impacted by first-generation antihistamines?
What is the effect?
- Cholinergic, alpha-adrenergic, and serotonergic receptors
- Increased risk of neuropsychiatric side effects, including sedation, confusion, hallucination, and delirium
Immunology Pathophysiology:
What type of hypersensitivity if contact dermatitis? ie poison ivy, oak, sumac, asiatic lacquer
What cell mediates this reaction?
Type 4 hypersensitivity mediated by T cells
Immunology Pharmacology:
What are the adverse effects of cyclophosphamide?
3 points
- myelosuppression
- SIADH
- hemorrhagic cystitis
Immunology Pharmacology:
What is the mechanism of action of cyclophosphamide?
Alkylating antineoplastic agent that crosslinks DNA at guanine bases
Immunology Immunology:
What immunoglobulin is most abundant in breast milk?
IgA
Immunology Pharmacology:
What is the mechanism of action of azathioprine?
- Thiopurine that acts as an immunosuppressant by inhibiting the purine metabolic
- its a prodrug form of 6-MP, preventing the proliferation of B and T lymphocytes
- combined with XO inhibitors potentiates the buildup of 6-MP
Immunology Pharmacology:
What is most concerning of azathioprine?
Bone marrow toxicity, avoid taking with XO inhibitors
Immunology Pharmacology:
What are some examples of xanthine oxidase inhibitors?
2 points
Allopurinol and febuxostat
Immunology:
What is the pathophysiology behind Hyper-IgM syndrome?
Impaired CD40L (Th cells) to CD40 (B cells) interaction, resulting in defective class switching of antibodies.
Immunology:
What is the inheritance pattern of Hyper- IgM syndrome?
XLR
Immunology Pathology:
What are the clinical features of Hyper- IgM syndrome?
- presents in infancy
- Severe recurrent infections:
–> Pneumonia: Pneumocystis jirovecii or histoplasma
–> Enteritis with cryptosporidium
–> hepatitis with cytomegalovirus
Immunology Pathology:
How would you diagnose Hyper- IgM syndrome?
Absent germinal center on lymph node biopsy.
Immunology Pharmacology:
How do you treat Hyper IgM syndrome? 4
- IV Ig
- Prophylactic antibiotics
- Filgrastim (Brand name: Neupogen, bone marrow stimulant)
- Allogeneic stem cell transplant (curative)
Microbio:
What is the stain for Tuberculosis?
Ziehl-Neelsen test
Uworld: Cell Mediated Immunity: Pharmacology:
What is the MOA of Abatacept?
A disease-modifying anti rheumatic drugs, it is a fusion of CTLA4 with the Fc portion of IgG. CTLA4 binds to CD80/86 on APCs, which prevents CD80/86 from binding to CD28 on T cells. This reduces T cell costimulation and leads to anergy, which reduces inflammation.
Note: Anergy= a form of peripheral immune tolerance marked by lack of T-cell response to cytokine, ligand, or antigen stimulation (T-cell inactivation)
Uworld: Pharmacology and Cytokines
What are the effects of high dose IL-2 in treatment of advanced renal cell carcinoma or metastatic melanoma?
- CD4 cells: converts CD4 cells into type 1 T-helper cells, which secrete inflammatory cytokines (eg, IFN-gamma, TNF-alpha, and IL-2)
- CD8 cells: IL-2 proliferates and increases their cytotoxic killing with granzymes and perforins
- NK cells: IL-2 triggers proliferation of NK cells and dramatically increases their cytotoxic activity; most of the anti tumor effect of IL-2 therapy comes form increased NK activity *
Inflammation
What cytokine is responsible for pus?
How does it work?
IL-8; responsible for neutrophil chemotaxis also induces phagocytosis
Bootcamp: Pathophysiology- SLE
What type of hypersensitivity is SLE?
Type 3; circulating immune complex deposition with complement activation causes widespread organ damage.
