MedGems Immuno Flashcards
Bullous pemphigoid antibodies
anti-hemidesmosome
high anti-GBM levels
Goodpasture’s syndrome
Rule out what infection before starting infliximab
TB
What antigen is injected intradermally as part of the mantoux screening test for tuberculosis?
tuberculin purified protein derivative
What is the target of the antibody P-ANCA?
myeloperoxidase
VZV what type of vaccine
live attenuated
Infections by what type of bacteria are more common in patients deficient in the complement protein C3?
encapsulated
A 21 year old woman reports weight loss, tiredness, diarrhoea and non-bloody offensive smelling stools. She has had three chest infections requiring antibiotics in the last three years. Blood tests are ordered and reveals a hypochromic, microcytic anaemia with low ferritin. Anti-TTG and anti-endomysial antibodies are negative. There are normal levels of IgG, IgM and IgE. No IgA is found.
What is the most likely cause of her gastrointestinal symptoms?
Coeliac Disease
Particular caution should be noted in the diagnosis of coeliac disease, as the common autoantibodies that are used for diagnosis are of the type IgA (Anti-Endomysial and Anti-Tissue Transglutaminase).
Hence, in IgA deficiency (1 in 600 people), they may be falsely negative.
IgA levels should always be assessed at the same time when assessing for coeliac disease.
What hematological cells create a “respiratory burst” in order to kill phagocytosed pathogens?
neutrophils
What monoclonal antibody targets IL-17 and is involved in the treatment of psoriasis, psoriatic arthritis and ankylosing spondylitis?
secukinumab
IgE antibodies bind semi-permanently to the surface of what cell of the innate immune system?
mast cells
A patient is investigated for a primary immunodeficiency. Lymphocyte counts are normal. However, IgG and IgA are low. There is an excess of IgM. What condition is this patient likely to have?
Hyper IgM
Hyper IgM is characterised by high levels of IgM in blood and reduction in levels of other immunoglobulin classes. IgM is the first antibody to be created during the immune response - all other classes of antibody require a process called class switching to occur. Class switching requires activation of CD40 on the surface of B lymphocytes to occur. When CD40 is defective, only IgM can be produced. Typically this leads to increased infection risk, particularly Pneumocystis pneumonia.
What type of bacteria are conjugated vaccines effective against?
encapsulated
What type of hypersensitivity is T cell mediated?
Type 4
What immune cell releases granzyme and perforin when activated?
T killer cells
What drug is given prophylactically to infants at high risk of developing life threatening RSV infection?
Pavilizumab
What lymphocyte lineage does cyclosporine predominantly inhibit?
T lymphocytes
CD8 is specifically a marker of what type of immune cell?
T killer cells
What assay is used as the first line test for HIV infection?
Enzyme Linked Immunosorbent Assay
What antiretroviral drug is given as IV monotherapy during labour to prevent vertical transmission of HIV-1?
Zidovudine
What monoclonal antibody targets CD20 and is used in the treatment of lymphomas?
rituximab
What is the minimum number of Fc receptors on the surface of mast cells that must bind to an antigen to cause mast cell degranulation?
2
What antigen does the immune system erroneously target in autoimmune thrombocytopenic purpura?
Glycoprotein IIb/IIIa
An prenatal autoimmune panel of bloods reveals positive anti-Ro antibody in the blood of a pregnant woman with SLE. What cardiological condition is her unborn baby at risk of?
Congenital heart block
What serine protease released by neutrophils causes hepatitis and emphysema in patients deficient in alpha-1 antitrypsin?
Neutrophil elastase
Which cell surface receptor allows cells of the innate immune system to bind to immunoglobulins?
Fc
What viral enzyme is predominantly responsible for the high mutation rate of HIV and other RNA viruses?
Reverse Transcriptase
In skin prick testing, what is used as a positive control?
Histamine
A 50 year old man is seen by the rheumatologists. The rheumatologists take a thorough history and the symptoms he experiences include: exquisitely painful fingers when entering the chilled aisle of his local supermarket, difficulty swallowing large bites of food, tight skin on his hands and around his mouth. In addition, he is easily fatigable and often feels feverish. His CRP is raised and an autoantibody is detected.
In the absence of other signs, what is the most likely diagnosis?
Limited Systemic Sclerosis
Which cytokine is important in the pathogenesis of rheumatoid arthritis, anyklosing spondylitis and inflammatory bowel disease?
Tumour Necrosis Factor Alpha
What type of vaccine uses weakened strains of a pathogen?
Live attenuated
What is the specific antigen recognised by the immune system in Goodpasture’s syndrome?
Type IV collagen
What autoantibody is associated with Microscopic Polyangitis?
P-ANCA
p-ANCA
UC, Eosinophilic Granulomatosis with Polyangiitis, Primary Sclerosing Cholangitis or Microscopic Polyangiitis
c-ANCA
Granulomatosis with polyangiitis (Wegner’s)
How long before skin prick testing must antihistamines be stopped to allow for accurate interpretation?
48 hrs
The paediatric SpR is called to review a 2 day old infant who is jaundiced, pyrexic and appears very unwell. The parents think he has a problem with his hearing as he did not cry when the fire alarm went off on the ward. He has a fever of 40.1C. Blood tests reveal an absolute neutropenia and absolute lymphocytopenia. What primary immunodeficiency is this patient likely to have?
Reticular dysgenesis
What immunoglobulin mediates type I hypersensitivity reactions?
IgE
The rabies and hepatitis A vaccinations are examples of what type of vaccination?
Inactivated
A neutrophil releases preformed myeloperoxidase, defensins and neutrophil elastase. What is this process known as?
Degranulation
What type of hypersensitivity reaction results when circulating antibodies directly react with self antigens leading to tissue damage?
Type II
What intracellular pro-proliferative molecule does cyclosporine and tacrolimus inhibit?
Calcineurin
What lymphocyte lineage does azathioprine predominantly inhibit?
T cells
What is the maximum number of viral capsids that a molecule of IgM may bind to?
10
What HLA allele is found in 90% of patients with coeliac disease?
HLA-DQ2
What HLA allele is associated with Graves disease?
DR3
A 80 year old woman was given a blood transfusion yesterday due to low haemoglobin. All observations normal. Infusion site is unremarkable. She feels like she has a fever. What complication of blood transfusion is this patient suffering from?
Febrile non-haemolytic transfusion reaction
What protein is defective in X linked Severe Combined Immunodeficiency?
Common Gamma Chain
A mutation in what protein is the most common cause of Hyper IgM syndrome?
CD40 ligand
positive anti-glycoprotein IIb antibodies
Autoimmune Thrombocytopenic Purpura
What test is the ability of a patient’s serum to lyse sheep erythrocytes coated with rabbit anti-sheep antibodies?
CH50
What mouse monoclonal antibody targets CD3 on the surface of T cells?
Muromonab
A 5 year old girl is seen by her GP. Her mother says she is unable to sleep at night as her knees, elbows and shoulders are very red and painful, especially to touch. Her mother has also noticed small bumps under her skin. She is currently pyrexic, but the mother says she is still recovering from a bad sore throat two weeks ago.
Acute Rheumatic Fever
Rheumatic fever is now a rare type II hypersensitivity reaction that may occur post-streptococcal infection.
The condition is diagnosed using Jones’ criteria:
Major criteria
Polyarthritis
Carditis
Subcutaneous nodules
Erythema marginatum (Rash on the trunk/arms which spread outward. Worse with heat)
Sydenham’s chorea (Involuntary movements of the face and arms)
Minor criteria
Fever
Arthralgia
Raised ESR/CRP
Leukocytosis
The Meningitis C vaccination is an example of what type of vaccination?
Conjugate