Intro to Immunology I
Viruses tend to replicate _________, while bacteria tend to replicate _________.
Bonus: Viruses are more likely to cause what kind of immune response? What about bacteria?
Bonus: Cell-mediated; antibody mediated
Why is the MMR vaccine contraindicated in immunocompromised patients but the hepatitis B vaccine isn't?
Bonus: What immunoglobulin will be made in response to a polysaccharide vaccine injection? Is this a T-cell independent or dependent reaction?
The MMR vaccine is live-attenuated, there is a risk of severe infections in immunocompromised patients. Hep B vaccine is inactivated (dead virus) so no chance of infection.
Bonus: IgM; this is a T-cell independent reaction
Cortisol levels have a ________ pattern normally. They are highest during this time of day and lowest during this time of day. Also, what effect do high levels of cortisol have on gonadotrophic hormones?
Bonus: Cushing's Disease is a result of too little/much cortisol. Name 3 symptoms of Cushing's Disease
Diurnal; morning, evening. High levels of cortisol suppress LH and FSH --> can delay puberty, cause hypogonadism and amenorrhea
Bonus: much; central redistribution of body fat, moon face, skin striae
How effective are antivirals at dealing with latent viruses? Explain your reasoning
Bonus: Antivirals kill viruses during active replication but only inhibit viruses during latency. True or false?
Antivirals are more effective at targeting viral proteins only present during active replication. However, antivirals can still be used as suppression therapy for latent viruses.
Bonus: False, antivirals do not kill viruses, they only inhibit viral replication.
Baloxavir (Xofluza) is used for the prophylaxis only of Influenza A and B, and is delivered PO as one single oral dose. True or False?
Bonus: What is a major non-CNS related contraindication of Amantadine (Symmetrel)?
False, Baloxavir is used for the treatment only of Influenza A and B, but is delivered PO as one single oral dose.
Bonus: End-stage renal disease (GFR < 15)
Describe the difference between PAMPs and DAMPs
Bonus: What is the most common pattern-recognition receptor and are they used in innate or adaptive immunity?
PAMPs are certain groups of carbohydrates and lipids found on microbes recognized by PRRs. DAMPs are released from infected/injured host cells.
Bonus: TLR (Toll-like receptors); innate
What is a hematologic cause of functional asplenia?
Bonus: Dendritic cells are known as cross presenters. What does this mean and what cells can they directly activate as a result?
Sickle cell anemia
Dendritic cells contain both MHC-I and MHC-II so they can present to, and activate both CD4 and CD8 cells immune responses
Name the class of primary secretions of the adrenal medulla, adrenal cortex (outer zona glomerulosa, middle zona fasciculata, and inner zona reticularis) and give an example of each.
Bonus: What are the most important therapeutic properties of glucocorticoids? What effects do inhaled steroids have on bronchi?
Medulla - Catecholamines (epi, NE), Outer - Mineralocorticoids (Aldosterone), Middle - Glucocorticoids (Cortisol), Inner - Adrenal androgens (DHEAS)
Bonus: Suppressing immunity and decrease inflammatory responses; Inhaled steroids increase bronchial response to bronchodilators.
Describe the 5 steps of the life cycle of a virus.
Bonus: What is a significant common ADR among antivirals?
1. Attachment and entry into host cell, 2. Uncoating of the viral genome within the host cell, 3. Synthesis of viral components within the host cell (genome is copied and genes are expressed to make viral proteins), 4. Assembly of viral particles (aka maturation), 5. Release of mature virus from host cell
Bonus: Nephrotoxicity
Bonus: If the infant was instead at high-risk for a serious RSV infection, which antiviral would be used?
Ribavirin (Virazole)
Bonus: Palivizumab (Synagis)
Bonus: How can you prove someone with hemoconcentration is not infected?
Hemoconcentration is a false elevation of WBCs due to dehydration. (Less plasma + same WBCs = false increase)
Bonus: Give the patient IV fluids and draw another CBC.
What characteristic of B cells, unlike other lymphocytes, allows it to bind to a broad range of antigens?
Bonus: What MHC does the B cell use and what happens after it presents an antigen to the CD4 cell?
Their surface psuedo-specific IgM or IgD antibodies
MHC-II; B-cells will: 1) recognize antigens with IgM/IgD receptor; 2) phagocytize the antigen and present to CD4; 3) CD4 will activate cytokines specific to B-cell replication and turning B cells into plasma cells
Why is it important to taper patients off steroids?
Bonus: Most ADRs of glucocorticoids are reversible over time....which aren't?
The production of endogenous cortisol by secretion of Adrenocorticotropin hormone (ACTH) in the hypothalamic-pituitary axis is suppressed while taking steroids. If stopped abruptly, patients can develop secondary adrenal insufficiency and decreased cortisol levels.
Bonus: Cataracts, Atherosclerosis, Decreased bone growth
Why is influenza A more common, pathogenic, and virulent than influenza B or C?
Bonus: Hemagglutinin receptors bind to _____ to enter the cell, while neuraminidase binds to and cleaves _____ to exit the cell.
Bonus: sialic acid; sialic acid
One patient is receiving Acyclovir (Zovirax) for HSV-1 and another patient is receiving Acyclovir (Zovirax) for VZV treatment. What is the main difference between how these medications are delivered?
Bonus: If the first patient switches to Valacyclovir (Valtrex), how might that impact pt adherence?
VZV is less susceptible to nucleoside analogs, so this patient should have a higher dose of acyclovir.
Bonus: Switching to Valacyclovir is likely to improve pt adherence as taking it requires less frequent dosing.
Describe the "let it ride" mentality behind vaccinating children. Why might this be important?
Bonus: Name 3 scenarios a fever can be present without infection.
Letting the immune response/inflammation run its course without using steroids/anti-inflammatories. These medications may lower resistance to infection.
Bonus: Inflammation; drugs (ex: cocaine); thyroid storm
Each individual B cell creates one specific antibody to fit multiple different epitopes. True or False?
Bonus: Describe how "class switching" takes place.
False, each B cell creates one specific antibody to fit one specific epitope
Co-stimulatory interaction between T and B-cell is required for class switching. CD4 cell produces IL-4, IL-5, which induce class switching from IgM to other classes
Fludrocortisone has more anti-inflammatory or mineralocorticoid use? What is it most commonly used to treat?
Bonus: What is Hydrocortisone commonly used to treat and why?
Mineralocorticoid; orthostatic hypotension
Bonus: adrenocortical insufficiency (Addison's Disease) because Hydrocortisone has good mixed glucocorticoid and mineralocorticoid properties
Why is an 18 year old on long-term aspirin therapy considered a high priority target for antiviral influenza treatment?
Bonus: Should you generally use influenza antivirals prophylactically on a healthy well-vaccinated person with known exposure within 48 hours?
Aspirin + flu or chickenpox = Reyes syndrome
Bonus: No, most individuals vaccinated against influenza during a season where vaccine antigens and circulating viruses are well-matched do not need prophylaxis.
Trifluridine (Viroptic) is used to treat patients with dendritic ulcers. True or False
Bonus: Can trifluridine be used systemically? Why or why not?
True, Trifluridine is used to treat HSV keratoconjunctivitis and patients with dendritic ulcers.
No, because incorporation of Trifluridine into both viral and host DNA prevents its systemic use since it inhibits both viral and host DNA.
What passive immunity method is most likely to cause Serum Sickness?
Bonus: What is the best course of action to take for someone bitten by a rabid dog that ran away after the bite?
Injection of heterologous antibodies
Bonus: Passive-active immunity by giving both IgG antibodies for immediate protection and the rabies vaccine for long term protection
What determines the class of an antibody? What about specificity?
Bonus: Which Ig is most abundant in newborns and which Ig do newborns produce themselves in high concentrations?
Class - heavy chain; specificity - variable region
Bonus: IgG (from mom, crosses placenta); IgM (everything is a primary response to newborns)
Out of the following medications, which is best to use for an infant presenting with mild dermatitis and why: Betamethasone dipropionate, Mometasone, Desonide, Clobetasol
Bonus: What effect do occlusive dressings have on topical steroids?
Desonide; this is a G6 topical steroid and has a low potency
Bonus: Occlusive dressings such as saran wrap will increase steroid potency
A patient received the IM influenza vaccine 3 days ago but has now tested positive for Influenza A. Is Oseltamivir (Tamiflu) contraindicated if you chose to treat this patient? Explain why.
Bonus: Zanamivir (Relenza) has significantly different ADRs than Oseltamivir (Tamiflu) despite both being NA inhibitors. Why?
Oseltamivir (Tamiflu) will not interfere with the IM vaccine because it is not live-attenuated. NA inhibitors would interfere with the intra-nasal vaccine.
Bonus: Zanamivir (Relenza) is given as an inhaler and common ADRs include: cough, bronchospasm, wheezing. Oseltamivir (Tamiflu) is given PO and common ADRs include: NVD, abdominal pain
What is Ganciclovir (Cytovene) indicated for and how does it's MoA differ from that of other nucleoside analogs?
Bonus: If a patient is not improving after taking Ganciclovir, which antivirals can be tried instead?
CMV retinitis/colitis; Ganciclovir does not use thymidine kinase, but instead uses viral-encoded phosphotransferase produced in CMV-infected cells for 1st phosphorylation --> the active compound then competitively inhibits incorporation of viral DNA polymerase and causes chain termination.
Bonus: Cidofovir (Vistide) or Foscarnet (Foscavir)