Immunology RACP MCQs Flashcards
RACP 2022a Q5.
A patient is anaphylactic to egg products, which viral vaccine is
contraindicated for this patient?
a. Yellow fever
b. MMR
c. Influenza
d. Varicella
Answer A
Anaphylaxis to vaccine components
Yellow fever vaccine is contraindicated in people who have had:
* anaphylaxis after a previous dose of any yellow fever vaccine
* anaphylaxis after any component of a yellow fever vaccine
* anaphylaxis to eggs
RACP 2022a Q55
55.What increases risk of Stevens-Johnson syndrome in carbamazepine use?
a. HLAB5801
b. HLAB1502
c. CYP3A4 polymorphism
d. CYP2B6 polymorphism
Answer B
Carbamazepine-induced SJS–TEN is strongly associated with the HLA-B*1502 allele
RACP 2022a Q71
71.What causes elevated triptan post anaphylaxis?
a. Mast cells
b. Steroids
c. Continued exposure to allergens
Answer A
Acute elevation of serum tryptase indicates degranulation of mast cells which occurs either due to an IgE-mediated mechanism, for example with penicillin allergy, or may result from direct degranulation of mast cells through non-IgE-mediated means, for example with NSAIDs or opiates
RACP 2022b Q2
- What is the reason for using ritonavir in co-formulation with lopinovir?
A. Increases loponovir’s potency
B. Inhibits liponavir metabolism
C. Reduces lopinovir gastrointestinal toxicity
D. Provides synergistic protease inhibition
Answer B
Lopinavir is metabolized by cytochrome P4503A (CYP3A) isoenzyme in the liver. Lopinavir is always used with ritonavir to reduce the dose of lopinavir and increase the plasma levels of lopinavir as ritonavir inhibits CYP3A isoenzyme. e small amount of ritonavir increases the bioavailability of the lopinavir
RACP 2022b Q5
- A patient with a history of ezcema develops itchiness, scaling and redness on her
earlobes after wearing new earrings. She also reports a similar skin reaction to her
jean button. You suspect a nickel allergy. What is the main mechanism causing this?
A. Cell mediated
B. Cytotoxic
C. IgE
D. Immune-antibody complex
Answer A
Allergic contact dermatitis represents the classic presentation of a T cell-mediated, delayed-type hypersensitivity response to exogenous agents. The initial step in the development of allergic contact dermatitis, as in nickel allergy, is hapten binding to a skin carrier protein. A hapten by itself is not immunogenic but becomes so after binding to a skin protein carrier. The hapten protein complex forms through covalent bonds between the hapten and amino acid side chains of target proteins within the skin.[8] The complex ultimately produces the sensitization of T cells. Sensitized T cells encountering the antigen at any time later will then lead to the release of cytokines, which in turn leads to macrophage activation and produces the immune response.[8] In summary, the sensitization process requires an initial exposure to allow the immune system to recognize the antigen later and lead to the immune response that causes ACD.
RACP 2022b Q13
13. Dupilumab works on IL4Ra. Besides affecting IL-4 levels, what else does it affect?
A. IL-5
B. IL13
C. IL17
D. IL23
Answer B
Dupilumab is an interleukin-4 (IL-4) receptor alpha antagonist. It is a human monoclonal antibody of the immunoglobulin G4 subclass that inhibits IL-4 and interleukin-13 (IL-13) signalling by specifically binding to the IL-4 receptor alpha subunit, which is shared by the IL-4 and IL-13 receptor complexes. Dupilumab inhibits IL-4 signalling via the type 1 receptor and both IL-4 and IL-13 signalling via the type 2 receptor. By blocking the IL-4R alpha subunit, dupilumab inhibits IL-4 and IL-13 cytokine-induced responses, including the release of proinflammatory cytokines, chemokines, and immunoglobulin E.
RACP 2022b Q29
- Besides experiencing a previous allergy to Pfizer vaccine, what else is a
contraindication to receiving the vaccine?
A. Anaphylaxis to egg
B. Latex
C. Neomycin
D. Polyethylene glycol
Answer D
The following people should be assessed to check they are suitable for vaccination:
people with immediate (within 4 hours) and generalised symptoms of a possible allergic reaction (such as urticaria/hives) to a previous dose of a COVID-19 vaccine, without anaphylaxis
people with a generalised allergic reaction (without anaphylaxis) to any component of the COVID-19 vaccine to be administered (such as PEG in Pfizer and Moderna, or polysorbate 80 in Novavax)
people with a history of anaphylaxis to previous vaccines or multiple drugs (injectable or oral) where a component such as PEG (for mRNA vaccines) or polysorbate 80 (for Novavax) may be the cause
people with a history of confirmed mastocytosis with recurrent anaphylaxis that requires treatment
RACP 2022b Q42
- Which immunoglobulin isotope is the most pathogenic as an auto-antibody?
A. IgA
B. IgG
C. IgM
D. IgD
Answer B OR C?
The presence of autoreactive antibodies is a hallmark of many autoimmune diseases. The effector functions of (auto)antibodies are determined by their constant domain, which defines the antibody isotype and subclass. The most prevalent isotype in serum is IgG, which is often the only isotype used in diagnostic testing
RACP 2022b Q43
- (Past question) Chimeric antigen receptor therapy utilises which type of cell?
A. B cells
B. T cells
C. NK cells
D. Macrophages
Answer B
CAR T cells are made by collecting T cells from the patient and re-engineering them in the laboratory to produce proteins on their surface called chimeric antigen receptors, or CARs. The CARs recognize and bind to specific proteins, or antigens, on the surface of cancer cells.
RACP 2022b Q51
- What is the trigger for alternate complement pathway?
A) IgG and IgM binding
B) Presence of sugars
C) Lack of complement regulatory proteins
Answer B
This pathway is activated byviruses, fungi, bacteria, parasites, cobra venom, immunoglobulin A, and polysaccharidesand forms an important part of the defense mechanism independent of the immune response.
RACP 2021a Q8.
Chimeric antigen receptor engineered cells are useful in treating some patients with haematological
malignancies. Which of the following is the main effector cell in this therapy?
A. B cells
B. Dendritic cells
C. NK cells
D. T cells
Answer D
CAR T cells are made by collecting T cells from the patient and re-engineering them in the laboratory to produce proteins on their surface called chimeric antigen receptors, or CARs. The CARs recognize and bind to specific proteins, or antigens, on the surface of cancer cells.
RACP 2021a Q15.
A 34 year old man is newly diagnosed with HIV. His CD4 count is 726 and his viral load is >80000. He is HBV
and HCV negative, and asymptomatic and otherwise well. When is the most appropriate time to start treatment?
A. Now
B. CD4 <200
C. CD4 <500
D. CD4 <500 and viral load >100,000
Answer A
RACP 2021a Q20.
A 45-year-old female who previously developed a rash after taking amoxicillin at the age of 5 years now has
streptococcal pneumonia. She has tolerated cephalosporins and roxithromycin previously without any reaction.
There is no family history of penicillin allergy.
Which of the following is the best indication to de-label her as having true penicillin allergy?
A. Age at which the reaction occurred
B. Tolerance to cephalosporins
C. Tolerance to roxithromycin
D. No family history of penicillin allergy
Answer A
Time elapsed since the reaction — The time elapsed since the last reaction is important because penicillin-specific IgE antibodies decrease over time, and therefore, patients with recent reactions are more likely to be allergic than patients with distant reactions [63-65]:
●Approximately 50 percent of patients with IgE-mediated penicillin allergy have lost the sensitivity 5 years after their last reaction.
●Approximately 80 percent of patients with IgE-mediated penicillin allergy have lost the sensitivity after 10 years.
Cephalosporins – Patients with a history of an immediate penicillin reaction who have tolerated one or more courses of cephalosporins subsequent to the penicillin reaction have proven themselves to not be allergic to cephalosporins, but they could still be allergic to penicillins. It is known that 98 percent of penicillin skin test-positive patients (to the major and/or minor penicillin determinants) are able to tolerate cephalosporins
RACP 2021a Q42
A man presents after a single episode of unprotected receptive anal intercourse with a male partner who is
known to be HIV positive. His partner is compliant with taking triple antiviral therapy and had blood tests 1 week
ago showing his HIV viral load was <20.
What is the chance of HIV transmission?
A. 0.01%
B. 0.1%
C. 1%
D. 10%
Answer A
HIV is transmitted sexually, parenterally (contact or exposure of body fluids) or vertically (from mother to baby)
Sexual transmission is responsible for ~80% of cases worldwide
Undetectable viral load is defined as less than 200 copies of HIV per mL of blood.
Significantly reduces and in some cases eliminates chances of HIV transmission if viral load is undetectable.
RACP 2021b Q103
Q103. The allergic reaction involved in serum sickness is primarily mediated by which of the following?
A. IgE
B. Antigen-antibody complexes
C. T lymphocytes
D. Complement activation
Answer D Type 3
Immune complex mediated
RACP 2021 Oct Q9
- When would you start prophylaxis for pneumocystis jiroveci pneumonia in a
HIV +ve patient?
a. CD4 count < 50
b. CD4 count < 100
c. CD4 < 400
d. CD 4 < 200
Answer D
RACP 2021 Oct Q28
When do b cells express CD20?
a. Plasma cell
b. Naïve B Cell
c. Mature B cell
d. Pro B cell
Answer C
CD20 (cluster of differentiate 20) is a protein that is expressed on the surface of B cells,starting at the pre-B cell stage and on mature B cells in the bone marrow and in the periphery. CD20 is not expressed on hematopoietic stem cells, pro-B cells, or normal plasma cells.
RACP 2021 Oct Q82
- What food allergy is implicated in exercise induced anaphylaxis?
a. Soy
b. Peanut
c. Milk
d. Wheat
Answer D
Food-dependent, exercise-induced anaphylaxis (FDEIA) – FDEIA is a disorder in which symptoms develop only if exercise takes place within a few hours of eating and, in most cases, only if a specific food to which the patient is sensitized is eaten in the pre-exercise period. It is the combination of the food (allergy) and exercise (cofactor) that precipitates attacks. Patients tolerate the culprit food in the absence of exercise, and they tolerate exercise in the absence of the culprit food. One of the most common food allergies to present as FDEIA is wheat allergy, or wheat-dependent EIA (WDEIA)
RACP 2021 Oct Q84
- Which cells are activated by Th17 lymphocytes?
a. B lymphocytes
b. Natural killer cells
c. Neutrophil
d. Dendritic cells
Answer C
Th17 cells represent a subset of CD4 effector T cells distinct from Th1 and Th2 lineages, and mediate powerful effects on stromal cells; this results in theproduction of inflammatory cytokines and recruitment of leukocytes, especially neutrophils, creating a link between innate and adaptive immunity
RACP 2021 Oct Q107
- What part of the complement system prevents C9 from binding to the
membrane attack complex?
a. CD59
b. Protein H
c. Protein I
d. ?
Answer A
In order to protect themselves from the complement attack, the cells express several regulatory molecules, including the terminal complex regulator CD59 that inhibits assembly of the large MACs by inhibiting the insertion of additional C9 molecules into the C5b-9 complex.
RACP 2020a Q3
- Choose the appropriate marker for peripheral blood stem cell precursor
A) CD19
B) CD20
C) CD34
D) CD38
Answer C
CD34 ispredominantly regarded as a marker of hematopoietic stem cells (HSC) and hematopoietic progenitor cells
RACP 2020a Q29
- How often should patients on PrEP (pre-exposure prophylaxis) be screened for HIV?
A) 3 monthly
B) 6 monthly
C) 12 monthly
D) After every high risk exposure
Answer A
RACP 2020a Q69.
In early disease, HIV binds to CD4 with which other co-receptor?
A) CCR5
B) CTLA4
C) CD3
D) CXCR4
Answer A
- HIV enters the body and attaches to cells with CD4 receptors via gp120 glycoprotein (on gp41 stalk).
- Viral envelope fuses with host cell – requires co-receptors CCR5 and CXCR4.
- Early stages – CCR5, later stages CXCR4
RACP 2020a Q72
72. Beta 2 microglobulin is a key component of which immunological cell?
A) B cell
B) T cell
C) MHC I
D) MHC II
Answer C
Beta-2-microglobulin (β2-microglobulin) is a component of MHC (major histocompatibility complex) class I molecules, present onall nucleated cells(excludes red blood cells).
RACP 2020a
73. What is the most important benefit of tenofovir alafenamide (TAF) compared to tenofovir disoproxil fumurate (TDF) in the treatment of human immunodeficiency virus or aquired immunodeficiency syndrome (HIV/AIDS)
A) Blockade of chemokine receptor type 5 (CCR5)
B) Elimination of nephrotoxicity
C) Improved efficacy as pre-exposure prophylaxis (PrEP)
D) Limited potential for drug resistance
Answer B
The nucleotide analogue tenofovir is used for the treatment of both HIV and hepatitis B, and for HIV pre-exposure prophylaxis. The original tenofovir disoproxil fumarate (TDF) version was developed at a dose of 300 mg once daily. A subsequent pro-drug formulation, tenofovir alafenamide (TAF), has been launched at doses of 10 or 25 mg once daily. The pharmacokinetics of TAF lead to a 6.5-times higher intracellular concentration of the phosphorylated moiety tenofovir diphosphate, and 91% lower serum concentration of tenofovir, compared to TDF. Given these pharmacokinetic differences, the dose of TAF can be far lower: Pharmacodynamic studies suggest that the lower tenofovir concentrations in plasma produced by TAF translate to reduced off-target exposure to the drug in the kidneys and bones, for example, with implications for adverse effect
RACP 2020
79. Problem with V(D)J cause deficiency in which lymphocyte?
A) B cell
B) B cell, T cell
C) B cell, NK, T cell
D) T Cell
Answer B
V(D)J recombination defect results in severe combined immune deficiency (SCID) with a lack ofT and B lymphocytesThe V(D)J recombination is a DNA rearrangement process that generates the diversity of T and B lymphocyte immune repertoire. It proceeds through the generation of a DNA double-strand break (DNA-DSB) by the Rag1/2 lymphoid-specific factors, which is repaired by the non-homologous end joining (NHEJ) DNA repair pathway. V(D)J recombination also constitutes a checkpoint in the lymphoid development.
RACP 2020b Q3
- Immunosuppressed grandma minding baby grandson getting live varicella vaccine. What precautions would you advise for the grandmother?
A. No precautions required
B. Avoid baby if he develops a rash
C. Prophylactic aciclovir
D. Avoid baby for 4 weeks
Answer A
Varicella vaccine is strongly recommended for household contacts of people who are immunocompromised.
Transmission of the varicella vaccine virus strain is extremely rare and is likely to cause only mild disease in the person who is immunocompromised (seeAdverse events). This compares with the relatively high risk of severe varicella disease from exposure to wild-type varicella-zoster virus in people who are immunocompromised
RACP 2020b Q30
- What cytokine is most implicated in the pathogenesis of auto-inflammatory conditions such as familial mediterranean fever?
A) IL-1
B) TNF-a
C) IL-7
D) IFN-Gamma
Answer A
Familial Mediterranean Fever (FMF) is the most common monogentic autoinflammatory disease. FMF results from mutations in MEFV, which lead to a pro-inflammatory state andincreased production of Interleukin 1 beta subunit (IL-1b) by myeloid cells
RACP 2019a
What is the marker for peripheral blood stem cells?
A. CD 19
B. CD 20
C. CD 34
D. CD 38
Answer C
CD34 ispredominantly regarded as a marker of hematopoietic stem cells (HSC) and hematopoietic progenitor cells
RACP 2019a
What vaccination besides H. influzenzae, pneumoccoal and meningococcal would you give to an asplenic patient?
A. Bordetella
B. Rubella
C. Influenza
D. Varicella zoste
Answer C
Vaccinations recommended in asplenia
Haemophilus influenza b
Influenza
Meningococcal
Pneumococcal
RACP 2019a
Down-regulation of MHC class I by tumour cells, exposes them to detection by what part of the immune system?
A. B cells
B. CD4
C. CD8
D. NK cells
Answer D
Natural killer (NK) cells express inhibiting receptors (iNKRs), which specifically bind MHC-I molecules on the surface of healthy cells. When the expression of MHC-I on the cell surface decreases, which might occur during certain viral infections and cancer, iNKRs lose inhibiting signals and the infected cells become target for NK cell activation (missing-self detection).
RACP 2019b
Question 4
Absence of what predisposes to atopic dermatitis?
A. Collagen
B. Filaggrin
C. Keratin
D. Kallikrein
Answer B
Atopic dermatitis is a chronic, pruritic, inflammatory skin disease that occurs most frequently in children but also affects adults, with an estimated worldwide prevalence in children of 5 to over 20 percent. A family history of atopy (eczema, asthma, or allergic rhinitis) and the loss-of-function mutations in the filaggrin (FLG) gene, involved in the skin barrier function, are major risk factors for atopic dermatitis
RACP 2019b Question 13
Which innate immune cell does Interleukin-5 act on?
A. Monocytes
B. Eosinophils
C. Neutrophils
D. Mast cells
Answer B
In humans, interleukin-5 acts only oneosinophils and basophils, in which it causes maturation, growth, activation, and survival
RACP 2019b
Question 39
In the context of allograft transplantation, which process may be triggered by donor APCs displaying donor antigens to recipient T Cells?
A. Acute cellular rejection
B. Humoral rejection
C. Graft-versus-host disease
D. T cell anergy
Answer A
The ability of recipient T cells to recognize donor-derived antigens, called allorecognition, initiates allograft rejection. Once recipient T cells become activated, they undergo clonal expansion, differentiate into effector cells, and migrate into the graft where they promote tissue destruction. In addition, CD4 T cells help B cells produce alloantibodies
Two distinct pathways of allorecognition. a Direct pathway of allorecognition. Dendritic cells migrate from the graft to secondary lymphoid tissues to activate T cells. b Indirect pathway of allorecognition. Graft proteins are processed by recipient dendritic cells and presented to T cells.
RACP 2019b
Question 63
In allogeneic stem cell transplant for acute myeloid leukemia, anti-thymocyte antibodies (ATG) are routinely administered as part of the conditioning regime. What is the benefit of ATG?
A. Prevent graft versus host disease
B. Enhance graft versus leukemia effect
C. Bone marrow recovery
D. Prevention of infection
Answer A
Anti-thymocyte globulin (ATG), a polyclonal antibody, is used in allogeneic hematopoietic cell transplantation (HCT) to prevent graft-vs.-host-disease (GvHD) and graft failure (GF). Anti-thymocyte globulin is a polyclonal antibody against human T cells. It is a gamma immunoglobulin produced by immunising rabbits. As well as depleting T cells in the circulation, anti-thymocyte globulin is also thought to reduce T cell proliferation, homing and cytotoxic effects within the body
ATG induces the generation of regulatory T cells (Treg), both in vitro and in vivo.31–33 This is clinically relevant given accumulating evidence showing an important role for
Treg in GvHD prevention after allogeneic HCT
RACP 2018b
107.Initiation of inflammation in acute gout is critically dependent upon which cytokine?
A. Interferon gamma.
B. Interleukin 1 beta.
C. Interleukin 13.
D. Interleukin 17.
E. Tumour necrosis factor.
Answer B
An acute attack of gout is a paradigm of acute sterile inflammation, as opposed to pyogenic inflammation. Recent studies suggest that the triggering of IL-1β release from leucocytes lies at the heart of a cascade of processes that involves multiple cytokines and mediators
RACP 2018b
114.In patients undergoing acute rejection of the renal allograft, biopsy specimens are likely to
show predominant infiltration of the graft by which one of the following?
A. B-cells.
B. Dendritic cells.
C. Macrophages.
D. T-cells.
E. Natural killer (NK) cells.
Answer D
Acute renal allograft rejection is defined as an acute deterioration in allograft function associated with specific pathologic changes in the graft. There are two principal histologic forms of acute rejection, acute T cell-mediated (cellular) rejection (TCMR) and active antibody-mediated rejection (ABMR). ABMR and acute TCMR may coexist at the same time in the allograft
ABMR: Histological features of ABMR include arteriolar fibrinoid necrosis, fibrin thrombi in glomerular capillaries, glomerulitis, peritubular capillaritis, and interstitial hemorrhage. Also, the presence of peritubular capillary linear staining for C4d, which is a degradation product of the complement pathway that binds covalently to the endothelium, is highly suggestive of ABMR.
Acute T Cell-Mediated Rejection: Characterized by diffuse lymphocytic infiltration in the tubule, interstitium of the kidney, and in severe cases, vessels of the allograft
RACP 2018b
130.What is the main purpose of somatic hypermutation in B cells?
A. Deletion of autoreactive B cells.
B. Expression of class II MHC.
C. Generation of receptor diversity.
D. Induction of anergy.
E. Selection of high affinity B cells.
Answer E
SHM in B cells provides the molecular basis for affinity maturation of antibodies. Affinity maturation: A process in which activated B cells interact with Th cells within the germinal center of secondary lymphoid tissue to secrete immunoglobulins with higher affinity for specific antigens
RACP 2018b
141.Control of Mycobacterium tuberculosis (MTB) replication is dependent on a number of critical
factors including TNF alpha production and IFN gamma response.
Which other immune effector plays a major role in controlling MTB replication?
A. B cell.
B. Complement.
C. Natural killer cell.
D. Neutrophil.
E. T cell.
Answer E
The immune response against Mtb is related to the presence of Th1 cells, leading to the production of mediators such as IFN-γ, which activate infected macrophages.
The immune response to M tuberculosis is T cell dependent. It comprises not only the conventional CD4 and CD8 T cells, but also γδ T cells and CD1 restricted T cells. γδ T cells recognise phospholigands and no presentation molecules are known thus far.
RACP 2018b
143.Tenofovir disoproxil fumarate is used in the management of HIV infection in combination with
other antiretrovirals. What is the site of action of tenofovir in the HIV life cycle?
A. HIV binding and entry of cells.
B. HIV protease activity.
C. HIV reverse transcriptase activity.
D. HIV viral assembly.
E. Integration of HIV DNA.
Answer C
RACP 2018b
146.Defects in the interleukin 12-dependent interferon gamma pathways are most likely to lead to
infection with which organism?
A. Candida albicans.
B. Herpes simplex.
C. Neisseria meningitidis.
D. Non-tuberculous Mycobacterium.
E. Staphylococcus aureus.
Answer D
Interleukin 12 receptor beta 1 (IL12Rβ1) deficiency is a primary immunodeficiency resulting mainly in susceptibility toopportunistic infection by non-tuberculous, environmental mycobacteria and severe infection caused by Salmonella spp.
RACP 2018b
150.Which acute-phase protein binds to phospholipid in foreign pathogens or damaged host cells?
A. C-reactive protein.
B. Ceruloplasmin.
C. Fibrinogen.
D. Mannose-binding lectin.
E. Serum amyloid A.
Answer A
A major function of CRP is its ability to bind phosphocholine, thereby permitting recognition both of foreign pathogens that display this moiety and phospholipid constituents of damaged cells. CRP can also activate the complement system and bind to phagocytic cells via Fc receptors, suggesting that it can initiate elimination of pathogens and targeted cells by interaction with both humoral and cellular effector systems of inflammation
Serum amyloid A binds to fibrin(ogen), promoting fibrin amyloid formation.
Ceruloplasmin binds to copper in the liver, circulates through the blood, and delivers the copper atoms to distant cells that use the atoms for basic processes
MBL binds to a range of sugars including N-acetyl-D-glucosamine, mannose, N-acetyl-mannosamine, fucose and glucose
RACP 2018a Q15
- A 19-year-old male is currently in hospital with his third episode of lobar pneumonia due to Streptococcus pneumoniae in the last 2 years. He reports a background of chronic sinus symptoms and frequent bronchitis, and takes 4–6 courses of antibiotics per year. He also reports intermittent nonbloody diarrhoea. Preliminary screening for immunodeficiency shows the following:
Pneumococcal antibodies: Normal values
Total IgG 14 mg/L [> 16]
IgG2 2 mg/L [> 5]
Immunoglobulins:
IgG 2.6 g/L [7–16]
IgA < 0.07 g/L [0.8–4.0]
IgM 2.5 g/L [0.4–2.5]
Lymphocyte subsets:
CD4+ 1023 cells/μL [500–1650]
CD8+ 477 cells/μL [210–1200]
NK 135 cells/μL [40–500]
CD19+ 0 cells/μL [80–600]
What is the most likely diagnosis?
A. Common variable immunodeficiency (CVID).
B. IgA deficiency.
C. Specific antibody deficiency.
D. X-linked agammaglobulinaemia.
E. X-linked hyper IgM syndrome.
Answer D
XLA is due to defects in a signal transduction molecule called Bruton tyrosine kinase (Btk). The diagnosis is suspected in a male patient with agammaglobulinemia/hypogammaglobulinemia, very low to absent CD19+ B cells, and a consistent clinical and/or family history.
CVID= reduced function of B cells not complete absence!
RACP 2018a
59. A 42-year-old Sudanese male is diagnosed with advanced HIV with a CD4 count of 50 cells/μL
[650–2000] and a viral load of 100,000 copies per mL. He is commenced on once daily
antiretroviral. Baseline screening demonstrates he is Epstein–Barr virus (EBV) IgG positive and Toxoplasmosis IgG positive.
One month after commencing treatment he develops fever and cervical lymphadenopathy.What is the most likely cause for his lymphadenopathy?
A. Drug reaction.
B. Glandular fever.
C. HIV-related lymphadenopathy.
D. Immune reconstitution inflammatory syndrome (IRIS).
E. Sarcoidosis.
Answer D
The term “immune reconstitution inflammatory syndrome” (IRIS) describes a collection of inflammatory disorders associated with paradoxical worsening of preexisting infectious processes following the initiation of antiretroviral therapy (ART) in HIV-infected individuals. Diagnosis of IRIS requires the worsening of a recognized (“paradoxical” IRIS) or unrecognized preexisting infection (“unmasking” IRIS) in the setting of improving immunologic function. Most patients with IRIS develop symptoms within one week to a few months after the initiation of ART
RACP 2018a
61. A 40-year-old HIV positive man with a CD4 count of 450 cells/μL [650–2000] presents with a 3 day history of fever, cough, sputum production and a right lower lobe consolidation on chest x-ray.
What is the most likely organism causing his pneumonia?
A. Methicillin resistant Staphylococcus aureus.
B. Mycobacterium avium complex.
C. Mycobacterium tuberculosis.
D. Pneumocystis jirovecii.
E. Streptococcus pneumoniae.
Answer E
RACP 2018a
66. A 31-year-old woman has a history of facial swelling with ibuprofen and aspirin. After spraining her ankle she took paracetamol 1 g four times daily, and on the third day she woke up with swollen eyelids and upper lip swelling.
What is the best explanation for this?
A. High-dose paracetamol inhibits COX-1.
B. Paracetamol causes direct release of mast cell contents.
C. She has an IgE-mediated reaction to an excipient common to all three medications.
D. She has an underlying non-allergic condition causing angioedema.
E. The paracetamol has been cross-contaminated with aspirin or ibuprofen.
Answer A
Approximately 20 percent of patients with aspirin-exacerbated respiratory disease react to acetaminophen at a dose of 1000 mg [24], since acetaminophen weakly inhibits COX-1 at higher doses. Patients with AERD are usually identifiable clinically by the presence of concomitant asthma and chronic rhinosinusitis..
RACP 2018a
69. Patients with drug reaction with eosinophilia and systemic symptoms (DRESS syndrome) are most likely to have additional involvement of which system in addition to the skin?
A. Cardiovascular.
B. Hepatic.
C. Neurological.
D. Renal.
E. Respiratory.
Answer B
Organ involvement – Involvement of one or multiple organs occurs in most patients with DRESS. Liver injury is most common, occurring in up to 90 percent of cases. Acute interstitial nephritis, interstitial pneumonia, and, less commonly, myocarditis can also occur
RACP 2018a
83. What is the main reason why immunotherapy (desensitisation) is routinely offered to patients with anaphylaxis caused by insect venom, but not to patients with anaphylaxis caused by food?
A. Desensitisation has no effect on food allergies.
B. Greater diversity of allergenic epitopes with foods.
C. Oral administration is less likely to induce tolerance.
D. Risk of anaphylaxis is higher with foods.
E. Sustained tolerance is harder to achieve with foods.
Answer E
Only a minority of patients treated with OIT (oral immunotherapy) achieve sustained unresponsiveness (SU) that is independent of regular food intake and is maintained even if the food is eliminated from the diet for long periods of time. Thus, for most allergens, it appears that OIT would need to be continued indefinitely to maintain a protective effect.
RACP 2018a
86. In addition to cytotoxic T cells, which other immune cell is primarily dysfunctional in the pathophysiology of haemophagocytic lymphohistiocytosis?
A. Dendritic.
B. Macrophage.
C. Mast.
D. Natural killer.
E. T helper.
Answer B
Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of multi-organ failure caused by unchecked macrophage- and lymphocyte-mediated inflammation. Underlying causes include inherited disorders of perforin-mediated cell-killing (primarily in infants/young children) and malignant, infectious, and autoimmune conditions in others
RACP 2017
Question 17
25-year-old man is found to have co-infection with HIV and HBV. Serology confirms active replication with HB eAg and HBV DNA load. What combination of two drugs will treat HBV and form the backbone of HIV treatment for this man?
A. Abacavir and Lamivudine
B. Lopinavir and Ritonavir
C. Daclatasvir and Sofosbuvir
D. Lamivudine and Dolutegravir
E. Tenofovir and Emtricitabine
Answer E
Because emtricitabine (FTC), lamivudine (3TC), tenofovir (TDF) and Tenofovir Alafanemide (TAF) have activity against both HIV and HBV, antiretroviral therapy should be initiated with a combination which includes TDF or TAF in the nucleoside reverse transcriptase inhibitor (NRTI) backbone of a fully suppressive antiretroviral regimen.
If TDF or TAF cannot safely be used, the alternative recommended HBV therapy is entecavir in addition to a fully suppressive ARV regimen(BI).
RACP 2017
What is the role of PD-1 (Programmed cell death protein) and PD-1 ligand antibodies?
A. B cell activation
B. NK cell inhibition
C. NK cell activation
D. T cell inhibition
E. T cell activation
Answer D
Under normal physiological conditions, the major function of PD-1 is toinhibit effector T-cell activity and enhance the function and development of Tregs, which inhibit T-cell responses and prevent overstimulation of immune responses in peripheral tissues.
CTLA-4 is thought to regulate T-cell proliferation early in an immune response, primarily in lymph nodes, whereas PD-1 suppresses T cells later in an immune response, primarily in peripheral tissues
RACP 2017
Which of the following is the target of the monoclonal antibody Bevacizumab?
A. EGFR
B. TNF alpha
C. VEGF
D. PD-1
E. CD20
Answer C
Angiogenesis is important for tumour growth and metastasis and is an important target for new biological agents. Bevacizumab is a humanized recombinant antibody that prevents vascular endothelial growth factor (VEGF) receptor binding and inhibits angiogenesis and tumour growth.
RACP 2017
What component of the immune system is most important in eliminating intracellular pathogens?
A. Complement
B. Antibodies
C. Eosinophils
D. T lymphocytes
E. Tumour Necrosis Factor
Answer ? D
Cytotoxic T lymphocytes (CTLs) play an important role in eliminating intracellular bacteria.
Natural killer (NK) cellsplay an essential role in killing intracellular pathogens through either cytotoxic attack of infected target cells or activation of macrophages via gamma interferon (IFN-γ) production.
RACP 2017
Question 40
What is the action of CTLA-4 on T cells?
A. Activates T cells
B. Inhibits activation of T cells
C. Allows B and T cell co-stimulation
D. Allows interaction between complement and T cells
E. Promotes antibody production
Answer B
CTLA-4 is a molecule expressed on T cells after activation and strongly binds to co-stimulatory molecules on antigen-presenting cells that prevent binding of these molecules needed for T-cell activation. The CTLA-4 moleculeacts as a halting mechanism, decreasing the function of T cells.
RACP 2017
Which of the following antibodies is most effective at fixing complement?
A. IgA
B. IgD
C. IgE
D. IgG
E. IgM
Answer E
The process of binding to C1, triggering activation of the classical pathway, and promoting assembly of the terminal membrane attack complex (MAC)is the process of complement fixation.
Complement fixation to IgM isstronger (>1000 times/antibody molecule) than that to IgG.
RACP 2017
Which of the above options describes the mechanism of action of the medications below?
Question 63
Mycophenolate Mofetil.
Options
a) Inhibition of Dihydroorotate dehydrogenase
b) Inhibition of inosine monophosphate dehydrogenase
c) Inhibition of dihydrofolate reductase
d) Regulate the expression of genes responsible for inflammatory mediators
e) Inhibition of calcineurin
f) Inhibition of CD25
g) Binding to CD3
h) Inhibition of Tumour Necrosis Factor
Answer B
Mycophenolate mofetil (MMF, CellCept) is a prodrug of mycophenolic acid (MPA), an inhibitor of inosine-5’-monophosphate dehydrogenase.MPA depletes guanosine nucleotides preferentially in T and B lymphocytes and inhibits their proliferation, thereby suppressing cell-mediated immune responses and antibody formation.
RACP 2017
Which of the above options describes the mechanism of action of the medications below?
Question 64
Prednisone.
Options
a) Inhibition of Dihydroorotate dehydrogenase
b) Inhibition of inosine monophosphate dehydrogenase
c) Inhibition of dihydrofolate reductase
d) Regulate the expression of genes responsible for inflammatory mediators
e) Inhibition of calcineurin
f) Inhibition of CD25
g) Binding to CD3
h) Inhibition of Tumour Necrosis Factor
Answer D
a) Inhibition of Dihydroorotate dehydrogenase – Leflunomide
b) Inhibition of inosine monophosphate dehydrogenase – Mycophenolate mofetil
c) Inhibition of dihydrofolate reductase – Methotrexate
d) Regulate the expression of genes responsible for inflammatory mediators – prednisone
e) Inhibition of calcineurin – Tacrolimus, cyclosporine
f) Inhibition of CD25 - Basiliximab Dacilizumab
g) Binding to CD3 - otelixizumab, teplizumab and visilizumab
h) Inhibition of Tumour Necrosis Factor- adalimumab, certolizumab, etanercept, golimumab, and infliximab
RACP 2018b
22. In addition to removing the cause, what is the immediate treatment for anaphylaxis?
A. Adrenalin 0.1 mg IV.
B. Adrenalin 0.5 mg IV.
C. Adrenalin 0.5 mg IM.
D. Adrenalin 1 mg IM.
E. Adrenalin 5 mg nebulised.
Answer C
The allergic reaction involved in serum sickness is mediated by which of the following?
A. IgE
B. Antigen-antibody complexes
C. T lymphocytes
D. Complement activation
RACP 2022 Q45
Thunderstorm asthma is triggered in people with allergy to which allergen
A. Birch
B. Olive
C. Rye grass
Answer C
Thunderstorm asthmais when asthma symptoms are caused byrye grasspollen allergy during springtime thunderstorms.
RACP 2016
Question 12
40 year old male with SJS due to amoxicillin (conjunctivitis, rash, penile and mucosal involcement). He improves once amoxicillin is ceased. In consultation with an allergy specialist, you recommend:
A. Organise testing of IgE levels against amoxicillin
B. Lifetime avoidance of beta lactam antibiotics
C. Intradermal skin prick testing for amoxicillin
D. Oral rechallenge with amoxicillin in a supervised environment
E. Desensitisation to amoxicillin
Answer B
Recurrent SJS/TEN with readministration of the causative drug or closely, chemically related agents has been widely documented in multiple case reports .The risk of recurrent SJS/TEN with structurally distinct agents (within the same therapeutic class of drugs) is unknown but probably very low.
RACP 2016
Question 55
A 45 year old male gardener is stung by a bee and suffers and anaphylactic reaction. What is the best ongoing management?
A. Avoid going outside
B. Desensitisation therapy to bee stings
C. Protective clothing
D. Prophylactic steroids and antihistamines
E. No action required
Answer B
Upon discharge, any patient with symptoms of a systemic allergic reaction or anaphylaxis should receive both of the following:
-Anepinephrineautoinjector and instructions about how and when to use it
-Referral to an allergy specialist to determine if he/she is a candidate for venom immunotherapy, which is the definitive treatment for venom allergy. Venom immunotherapy reduces the risk of a recurrent life-threatening reaction to a subsequent sting to less than 5 percent. Allergy specialists can also provide patients with detailed advice about strategies for avoidance.
RACP 2016 Question 83.
An 18 year old girl presents with Neisseria meningitidis bacteraemia. On further investigation, she has had recurrent similar episodes of meningitis for 10 years.
Which is the most important diagnosis to exclude?
A. Chronic granulomatous disease
B. Common variable immunodeficiency
C. Hyper IgE
D. IgA deficiency
E. Membrane attack complex deficiency
Answer E
The membrane attack complex / MAC plays an important role in neutralizing Neisseria and deficiencies thereforepredispose to infection with meningococci and gonococci. Deficient individuals typically present after the age of ten with recurrent episodes of meningococcal meningitis.
RACP 2016
Question 3
Compared to adaptive immune system, one ofthe cardinal features of innate immune system is:
A. Diversity
B. Inflammation
C. Memory
D. Specificity
E. Self-tolerance
Answer ?B
Adaptive immune system is antigen specific, has immunological memory and diversity of receptors to recognize millions of antigen epitopes.
Innate immune system is rapid, antigen independent and leads to inflammation
RACP 2016 Question 5
The C-reactive protein (CRP) is a commonly requested test in the investigation of fever. Where in the immune system does CRP work?
A. Adaptive immune system
B. Antigen presentation
C. Complement
D. Innate immune system
E. Leukocyte adhesion.
Answer D
CRP belongs to a family of pentraxins – which are circulating pattern recognition receptors.
A major function of CRP is its ability to bind phosphocholine, thereby permitting recognition both of foreign pathogens that display this moiety and phospholipid constituents of damaged cells.
CRP plays arole in inflammationby
Activating C1q – classic complement pathway – leads to opsonization,phagocytosis
Binds to Fc portion of Ig – activates release of inflammatory cytokines
Acts as a PRR – recognize PAMPs/DAMPs
RACP 2016
Question 24
If MHC class 1 expression is downregulated by a virus, which of the following cells will be unable to act?
A. CD19 lymphocytes
B. CD4+ T cells
C. CD8+ T cells
D. Dendritic cells
E. NK cells
Answer C
In humans as in other animal species, CD8+cytotoxic T lymphocytes (CTLs) play an important if not the major role in controlling virus-infected and malignant cell growth. The interactions between CD8+T cells and target cells are mediated by human leukocyte antigen (HLA) class I antigens loaded with viral and tumor antigen-derived peptides along with costimulatory receptor/ligand stimuli. Thus, to escape from CD8+T-cell recognition and destruction, viruses and tumor cells have developed strategies to inhibit the expression and/or function of HLA class I antigens. In contrast, cells with downregulated MHC class I surface expression can be recognized by NK cells, although NK cell-mediated lysis could be abrogated by the expression of inhibiting NK cell receptors
RACP 2015a
Question 9
A 16 year old male presents with recurrent sinus infections on the background of three
previous ICU admissions for pneumonia. His investigations are as follows:
Mild anaemia
Normal WCC and differential (multiple B and T cell lineage markers given, all normal)
Normal platelets IgG mild-moderately low compared to reference range IgM very low compared to reference range. All other immunoglobulin levels unremarkable
What is the most likely diagnosis?
A. Chronic granulomatous disease
B. Common variable immunodeficiency
C. Leukocyte adhesion deficiency
D. Severe variable immunodeficiency
E. X linked agammaglobulinemia
Answer B
CVID - Common variable immunodeficiency (CVID) is the most common form of severe antibody deficiency affecting both children and adults. The characteristic immune defect in CVID is impaired B cell differentiation with defective production of immunoglobulin. CVID is defined by low total serum concentrations of immunoglobulin (Ig)G, as well as low IgA and/or IgM, poor or absent response to immunization, and the absence of any other defined immunodeficiency state.Bacterial infections of the sinopulmonary tract, particularly sinusitis and pneumonia, are experienced by most patients with CVID
RACP 2015b
In renal allograft rejection, what is the primary cell involved?
A. B lymphocytes
B. T lymphocytes
C. NK cells
Answer B
Both innate and adaptive immune systems play a significant role in rejection, but the T lymphocytes are the principal cells that recognize the allograft
RACP 2015b
Acquired angioedema in autoimmune systemic diseases due to failure of inhibition of which component of the complement cascade:
A. Alternative pathway
B. Classical pathway
C. Factor H
D. Mannose Lectin pathway
E. Terminal attack complex
Answer B
Acquired angioedema (AAE) is characterized by acquired deficiency of C1 inhibitor (C1-INH), hyperactivation of the classical pathway of human complement and angioedema symptoms mediated by bradykinin released by inappropriate activation of the contact-kinin system.
RACP 2015b
Question 41
Hereditary angioedema which complement pathway:
A. Classic
B. Alternative
C. Lectin
D. Common
E. Rhubarb
Answer A
Most cases of hereditary angioedema (HAE) are caused by a deficiency or dysfunction of C1 esterase inhibitor (C1-INH), resulting in the inability to regulate the contact system. C1-INH inhibits plasma kallikrein and coagulation factor XIIa.Low levels of C1 inhibitor, the main inhibitor of the classic complement system, result in paroxysmal angioedema attacks.
RACP 2015b
Question 55
Which of the following would be the most likely investigation to diagnose primary
immunodeficiency in a 25year old lady who presents with recurrent sinopulmonary
infections?
A. A THC/CH50
B. B IgM
C. C IgG
D. D CD4 count
E. E CD8 count
Answer C
Common variable immunodeficiency (CVID) is the most common form of severe antibody deficiency affecting both children and adults. The characteristic immune defect in CVID is impaired B cell differentiation with defective production of immunoglobulin. CVID is defined by low total serum concentrations of immunoglobulin (Ig)G, as well as low IgA and/or IgM, poor or absent response to immunization, and the absence of any other defined immunodeficiency state. Bacterial infections of the sinopulmonary tract, particularly sinusitis and pneumonia, are experienced by most patients with CVID.
The diagnosis of CVID requires a suggestive clinical history, a reduced total serum concentration of IgG, plus low IgA or IgM, and poor responses to both protein- and polysaccharide-based vaccines.
RACP 2015b
What is the mechanism of action of Ipilimumab?
A. Cytotoxic T Lymphocyte Inhibitor
B. Cell check point modulator
C. Vascular Endothelial Growth Factor Inhibitor
D. Interleukin 2 Inhibitor
E. Rhubarb
Answer A
Ipilimumab is an anti-CTLA-4 monoclonal antibody that prevents CD80 and CD86 on APCs from binding to CTLA-4 on T cells. This blockage of CTLA-4 signaling allows T-cell activation, proliferation, and amplification of T-cell-mediated immunity, which allows the patient’s immune system to mount a better response
RACP 2015b
Question
The yellow fever vaccine is a live attenuated vaccine. In which of the following situations is it safe to give the yellow fever vaccine?
A. Asplenia
B. Giant cell arteritis on 25mg/d prednisone for last 3 months
C. HIV with CD4 count of 180
D. Pregnancy
E. Rhubarb
Answer A
Vaccine-related disease can be caused by unchecked infection (replication) by the live vaccine virus or bacteria. This is especially true for: BCG, MMR and VZV
- have HIV - (CD4+ count of >200 per µL) can receive yellow fever vaccine if they are at risk of infection. People with HIV should only receive yellow fever vaccine if potential exposure to yellow fever virus is unavoidable.
- are taking highly immunosuppressive therapy, including bDMARDs or tsDMARDs (biological or targeted synthetic disease-modifying anti-rheumatic drugs), or high-dose corticosteroids (> 20 mg/day for >14 days)
- Pregnant women - Yellow fever vaccine is not recommended, other than in exceptional circumstances
- Asplenia alone is not a contraindication for any vaccination, including live vaccines.
RACP 2015b
Question
A woman in her 30s presents 90 days post renal transplant. The post-operative course has thus far been unremarkable. She is febrile with malaise and rigors. Her medications include tacrolimus, MMF, prednisone, valganciclovir and Bactrim.
What is the most likely aetiology?
A. BK (polyoma) virus
B. CMV
C. E coli
D. Rhubarb
E. Rhubarb
Answer A vs C
RACP 2014a Q4
Question 4:
A female with recurrent attacks of facial and lip swelling without rash, presents to hospital after her fifth attack. She states that she awoke from sleep with her current symptoms. She has been unable to identify any triggers. What investigation would be most useful in identifying the cause of her symptoms?
1. Eosinophils
2. Tryptase level
3. IgE
4. IgE to peanut
5. C4