Med GEMS questions Flashcards
Aminoglycosides act on which part of the bacterial ribosome?
30S
Which antimicrobial agents work by inhibiting bacterial protein synthesis?
There are 5 main groups of antimicrobial agents that work by inhibiting bacterial protein synthesis. These can be remembered using the acronym TAMCO:
Tetracyclines (e.g. Doxycycline)
Aminoglycosides (e.g. Gentamicin)
Macrolides (e.g. Erythromycin)
Chloramphenicol
Oxazilidinediones
Aminoglycosides and Tetracyclines work by binding to the 30S subunit of ribosomes.
Macrolides and Chloramphenicol work by binding to the 50S subunit of ribosomes.
Oxazilidinediones works by binding to the 23S component of the 50S subunit of ribosomes.
What is Kernig’s Sign?
A patient with suspected meningitis is asked by their consultant to lie supine, with a flexed hip and knee.
The consultant passively extends both knees slowly. However, the patient stops the doctor and refuses to extend the knee past 120 degrees of flexion due to pain.
In what cell in the human body do Leishmania parasites multiply?
Macrophages
Describe Mucocutaneous Leishmaniasis
This form of leishmaniasis causes skin and mucosal ulcers of the nose and mouth.
This is generally treated. Examples of therapies include sodium stibogluconate, liposomal amphotericin B or meglumine antimonate.
What is the recommended antibiotic prophylaxis for bites by either cat, dog or human in a patient with no known allergies?
Co-amoxiclav
What class of antibiotics does azithromycin belong to?
Macrolide
What class of antibiotics does ceftriaxone belong to?
Third generation cephalosporin
To which class of antibiotics does meropenem belong?
Carbapenems
Cancer of what organ is commonly associated with schistosomiasis infection?
Bladder cancer
What growth medium is used to differentiate Streptoccoci in the laboratory setting?
Blood agar
Beta Haemolytic (pale blood agar) -> Lancefield Grouping
How is Q fever typically diagnosed?
Serology
Q Fever is caused by what disease?
Coxiella burnetti
What is the first line antimicrobial for treatment of Lyme Disease?
Doxycycline
A pregnant woman at term (38+3) has her urine dipped which shows the presence of nitrites and leukocytes.
However, she denies any dysuria or other symptoms.
If indicated, what is the first line antibiotic for the treatment of this patient?
Cefalexin
What is the appropriate treatment for Visceral Leishmaniasis?
Liposomal amphotericin B
Leishmaniasis is spread by which vector?
Sandfly
What class of antibiotics does ciprofloxacin belong to?
Fluoroquinolones
To what family of viruses does SARS-CoV-2 belong?
Coronaviridae
What is the treatment for human tapeworms in adults?
Praziquantel
What antibiotic would you prescribe first line for an infective exacerbation of COPD with a suspected bacterial etiology?
Amoxicillin
What subtype of Herpes Simplex Virus is typically implicated in encephalitis?
HSV 1
What is the primary infective lesion produced by Mycobacterium tuberculosis called in the lungs?
Ghon focus
A “Ghon focus” is the primary site of infection by Mycobacterium tuberculosis in the lungs. It is typically found in the lower zones towards the periphery of the lung and often calcifies over time.
What assay is currently used to identify if someone has previously been infected with SARS-CoV-2?
ELISA
Which first-line Tuberculosis medication causes visual disturbances?
Ethambutol
Which malarial species presents with a 72 hour fever pattern?
Plasmodium malariae
Presence of atypical lymphoycytes on a peripheral blood film suggests what diagnosis?
Epstein barr virus
What is the full scientific name of the organism responsible for Q Fever?
Coxiella burnetti
What is the first line antibiotic for the treatment of acute otitis media in a patient with no known allergies?
Amoxicillin
Example of an Aminoglycosides?
Gentamicin
Example of a macrolide?
Erythromycin
What class of organisms are classically the hosts for Coxiella Burnetii?
Mammals
Describe Q fever
Q Fever (Coxiella Burnetii) is a disease characterised by abrupt onset of flu-like symptoms, fever, headache, muscle pain, chills which may progress (for exam purposes) to an atypical pneumonia and ARDS or endocarditis. However, most patients are asymptomatic.
Treatment for Q fever?
doxycycline or ciprofloxacin.
Which class of antibiotic does vancomycin belong to?
Glycopeptide
A 23 year old woman sees her GP complaining of deep dyspareunia with her new partner. She has never had an STI check before.
Speculum examination shows an erythematous, oedematous cervix.
A vaginal swab is taken and reveals a gram negative diplococcus.
What organism is likely responsible for her symptoms?
Neisseria gonorrhoea
Which first-line Tuberculosis medication causes hyperuricaemia?
Pyrazinamide (also causes hepatotoxicity)
A 39 year old alcoholic is admitted to the respiratory ward due to a chest infection.
There are crepitations in the left mid zone and this is associated with consolidation on X ray.
Past medical history is unremarkable.
Sputum culture showed Gram Negative Rods in clusters.
What organism is responsible for his chest infection?
Klebsiella pneummoniae
A 55 year old gentleman is referred to gastroenterology by his GP.
He has persistent dysphagia and weight loss. He has no other past medical history.
At endoscopy a diagnosis of oesophageal candidiasis is made.
What is the next most appropriate investigation?
HIV test
What antibiotic should be prescribed for a penicillin allergic, clinically stable patient with cellulitis?
Clarithromycin
A patient is suspected to have a community acquired pneumonia. Their CURB 65 is 1. Atypical infection is not suspected.
If indicated, what is the first line antibiotic for the treatment of this patient?
Amoxicillin
What viral enzyme is inhibited by oseltamivir?
Neuraminidase
A sputum sample is taken from a 56 year old patient suffering from treatment resistant asthma.
They have an elevated serum IgE level. Their symptoms responded very well to steroids but rapidly returned after cessation of steroids. The respiratory consultant suspects Allergic Bronchopulmonary Aspergillosis.
What is an appropriate histological stain to use on this sputum sample to identify the responsible organism?
Methenamine Silver Stain
Test for identifying Candida/Asperg/PCP?
Beta-D-glucan
Test for identifying cryptococcus?
Glucuronoxylomannan (GXM)
What is the first line antimicrobial for treatment of gonorrhea?
Ceftriaxone
A 15 year old swimmer present with a month long history of itching and scaling between the toes on his right foot.
On examination there is macerated skin between the 3rd and 4th toes on the right foot, associated with erythema and scaling.
What organism is most likely responsible for this presentation?
Tricophytum rubrum
Hepatitis D is a subviral satellite that can only replicate in the presence of what other virus?
Hepatitis B
A 72 year old man with COPD and poorly controlled HIV presents to the emergency department following a severe episode of haemoptysis. He reports no other symptoms.
A high resolution CT scan reveals multiple large bullae and a large left upper lobe rounded mass surrounded by a crescent of air.
Serum galactomannan is positive.
What is the diagnosis?
Aspergilloma
A 23 year old medical student recently returned from her African medical elective presents with a 7 day history of of fever, myalgia and headaches.
What diagnostic investigation should be requested?
Thick blood film
What antibiotic is used to treat bacterial vaginosis and may be given as either as a STAT dose or as a weekly course?
Metronidazole
A 25 year old female presents for an STI screen.
She reports feeling feverish, has diffuse lower abdominal pain and dyspareunia.
A Nucleic Acid Amplification Test (PCR) is positive for the presence of a gram negative intracellular bacterium.
What is the likely causative organism?
Chlamydia trachomatis
Infection with HPV subtypes 6 and 11 typically causes what condition?
Genital warts
In immunocompetent patients, what is the typical presentation of listeriosis?
Gastroenteritis
A 16 year old athlete is seen by a pharmacist for an itchy white rash between his toes.
In addition to general hygiene advice, what topical antifungal cream may be used to treat this condition?
Clotrimazole
To what phylum do the organisms Leptospira spp, Borrelia spp, Treponema spp and Brachypsira spp belong?
Spirochaetes
A 34 year old is admitted to the respiratory ward due to a severe chest infection. There are crepitations in the right mid zone and this is associated with consolidation on X ray.
Past medical history is unremarkable. The patient says that he is recovering from the flu, which he had last week.
Sputum culture showed Gram Positive Cocci in clusters.
What organism is responsible for his chest infection?
Staphylococcus Aureus
A 2 month old baby presents to the A&E with a fever of 39.5C, feeding <50% of normal and is very drowsy.
In addition to cefotaxime, what other antibiotic would you start empirically?
Ampicillin
What antimicrobial is first line for severe, widespread fungal nail infection in a an elderly patient with no known allergies?
Recent bloods including FBC, U&Es, LFTs and TFTs were all normal.
Terbinafine
What is the gold standard diagnostic test for Leishmaniasis?
Splenic aspirate
What is the vector of transmission for Dengue virus?
Female aedes mosquito
What is the scientific name of the beef tapeworm?
Taenia saginata
A 50 year old woman is seen by her GP with 3 days of mild headache, sneezing and coughing. She also has a sore throat. She takes ramipril for hypertension but has no other past medical history.
On examination her chest is clear, there is no cervical lymphadenopathy and no visible exudate on the tonsils.
What is the likely responsible organism?
Rhinovirus
A 73-year-old immunocompromised man presents to the Emergency Department with a 3-day history of fever, dry cough, muscle ache and severe headache. There is no sign of meningism. Respiratory and cardiovascular exam is normal.
A rapid flu swab is positive for Influenza A and RT-PCR for SARS-CoV-2 on a NP swab was negative.
What antiviral drug may be indicated for this patient?
Oseltamivir
What organism is responsible for the sexually transmitted infection Chancroid, which causes multiple painful ulcers?
Haemophilus ducreyi
A 18 year old man reports significant discolouring of one of his great toenails with associated onycholysis of that nail. There is a small amount of nail pitting visible also. No other nails are affected.
You decide to send the sample for culture but wish for a quicker result in the meantime.
What test would be appropriate to order to determine if treatment is needed?
Potassium hydroxide test
A 20 year old white man presents to their GP having noticed the development of a rash on his back over the last few months. He reports no symptoms from it.
On examination, there are scaly areas of hypopigmentation across the back. There is no evidence of erythema or excoriation.
Under Wood’s Lamp, the patch fluoresces a very faint orange colour.
Pityriasis versicolor
A 38 year old woman suddenly feels unwell and develops severe vomiting.
She last ate some chicken around 2 hours ago that she thought was undercooked.
What is the likely responsible pathogen?
Staph aureus
During which trimester of pregnancy is the risk of HSV transmission to a neonate greatest?
Third trimester
What is the name of the neurological sign of a pupil that accommodates, but does not react to light?
Argyll-Robertson pupil
What is the first line antibiotic for the treatment of a bacterial sore throat in a patient with a penicillin allergy?
Clarithromycin
What gram positive organism is associated with tumbling motility and rockets?
Listeria monocytogenes
Give an example of a beta haemolytic Streptoccoccus
Streptococcus agalactiae
What diagnostic test is used to diagnose chlamydia infection?
Nucleic Acid Amplification Tests
What antiviral drug is typically given prophylactically to patients undergoing allogenic stem cell transplantation to protect against CMV infection?
Gancyclovir
A child is suspected of having meningococcal septicaemia in the GP setting.
As you prescribe the medication, you note the child has a documented reaction to flucloxacillin, when they developed a mild rash.
What medication, if any, should the GP administer in the practice, before arranging immediate hospital admission?
Benzylpenicillin
A sexually active homosexual man received treatment two hours ago for genital primary syphilis.
He was given a single of dose of IM benzylpenicillin.
He presents to the emergency department reporting he has become unwell, with a fever, headache and muscle aches. He is concerned he is having an allergic reaction.
He is pyrexial at 38C and his blood pressure is 98/76.
What syndrome is he suffering from?
Jarisch Herxheimer reaction
What is the first line antibiotic for the treatment of sinusitis in a systemically well patient with no known allergies, assuming there has been no improvement of symptoms for at least 10 days?
Penicillin V
A 50 year old lady of previous good health presents to her GP with multiple unsightly, discoloured, brittle toenails. Underneath each toenail is a chalky material.
The GP suspects multiple fungal nail infections. Nail scrapings grew dermatophytes and a PoC HIV ELISA is negative.
Prior to starting terbinafine, a systemic antifungal, what blood test should be ordered?
LFTs
A 34 year old music producer is seen in the acute medical unit.
His GP sent him for review after blood tests for persistent fatigue revealed a normocytic anaemia with a haemoglobin of 84g/L.
He reports traveling back from Brazil three weeks prior, where he delivered school supplies to a rural preschool. He states he was compliant with all the travel advice and vaccinations offered in the UK before he left.
He also says he has been sleeping poorly since arriving back in the UK, as he finds it uncomfortable to lay on his left side.
On examination there is clear splenomegaly. A blood film is unremarkable. Thick blood film for malarial parasites is negative.
What is the likely diagnosis?
Visceral leishmaniasis (black fever)
A 33 year old man presents to their GP with multiple elevated, small, pink lesions with a dimple in the center over his abdomen.
He denies any pain, itching or bleeding. They are not obviously infected. He has no history of cold sores and had chickenpox as a child.
What infection must be ruled out in a person presenting with this characteristic rash?
HIV
What is the most common organism that causes an aseptic meningitis?
Enteroviruses
What are the pathogenic antibodies in bullous pemphigoid?
anti-hemidesmosomes
A 34 year old man has severe Crohn’s disease. His gastroenterologist wishes to start a biologic drug, infliximab. What infection should be ruled out before commencing the drug?
Tuberculosis
What type of vaccine is comprised of a polysaccharide bound to a immunogenic toxin?
Conjugate
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
Target of c-ANCA?
Proteinase-3 = Granulomatosis with polyangiitis (Wegner’s)
The MMR, VZV and yellow fever vaccines are what type of vaccination?
Live attenuated
Infections by what type of bacteria are more common in patients deficient in the complement protein C3?
Encapsulated
A 80 year old lady received 2 units of FFP 4 hours ago due to a severe nosebleed and an INR of 4.8 on admission.
She takes wafarin for a metallic heart valve. Over the last hour, she is beginning to feel short of breath, especially when lying down. She is hypotensive at 95/40 and SpO2 of 94% on 8L/min O2.
She is pyrexic at 37.8C.
What complication of blood transfusion is she suffering from?
Transfusion Related Acute Lung Injury
What auto-antibody is associated with Eosinophilic Granulomatosis with Polyangiitis (Churg Strauss)?
p-ANCA
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
What immunomodulatory agent may be given to treat chronic granulomatous disease?
Interferon Gamma
What monoclonal antibody targets IL-17 and is involved in the treatment of psoriasis, psoriatic arthritis and ankylosing spondylitis?
Secukinumab
What is the main metabolite of azathiroprine?
6-Mercaptopurine
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 syndrome
What is the inheritance pattern of reticular dysgenesis?
Autosomal recessive
What class of medication acts by inhibiting phospholipase A2 and reduces the expression of pro-inflammatory cytokines?
Corticosteroids
What type of bacteria are conjugated vaccines effective against?
Encapsulated
Subunit (recombinant) Vaccine examples?
Typically for viruses.
The vaccine contains proteins found on the surface of the viruses in addition to an adjuvant. Examples include Hep B and HPV.
Inactivated vaccines
These are vaccines where the pathogens have been rendered inert - usually by heat killing or formaldehyde.
Examples include the pertussis vaccine.
As the pathogen cannot replicate, it usually requires multiple booster shots to provide immunity.
How is ANA is typically detected?
Indirect immunofluorescence
Homogenous pattern of ANA staining suggests which antibodies?
Anti-dsDNA
speckled pattern of ANA staining suggests which antibodies?
Anti-centromere (CREST syndrome/limited cutaneous sclerosis)
The paediatric SpR is called to review a 16 day old infant who is pyrexic and appears unwell. His umbillical cord stump is still present, non-purulent, red, tender and hot. He has a fever of 39C. Blood tests reveal a neutrophil count of 16 (normal range: 1.5-8.0) What primary immunodeficiency is this patient likely to have?
Leucocyte adhesion deficiency
A rare autosomal recessive immunodeficiency. Neutrophils are unable to adhere to vascular endothelial - hence they cannot transmigrate into tissues to fight infection. This leads to a high level of neutrophils in the blood (neutrophilia). As a result, there is no abscess formation or pus.
What immune cell releases granzyme and perforin when activated?
CD8+ T cells
What lymphocyte lineage does cyclosporine predominantly inhibit?
T lymphocytes
What do tacrolimus and cyclosporine inhibit?
Calcineurin, a protein needed for T cell proliferation,
A 20 year old man is screened for primary immunodeficiencies by his GP after a number of recent, severe infections.
A full blood count was normal.
IgA Normal
IgM Low
IgG Low
What immunodeficiency is this patient likely to have?
Common variable immunodeficiency
An 9 year old boy has had recurrent chest infections and influenza like illnesses since joining primary school.
Blood tests reveal a low lymphocyte count, with very low B cells but normal T cell levels.
There as very low levels of IgM, IgA and IgG.
What immunodeficiency is this patient likely to have?
Bruton’s Agammaglobulinaemia. Bruton’s Agammaglobulinaemia is a rare X linked immunodeficiency caused by a mutation in the BTK gene, which codes for a tyrosine kinase required for B cell development.
Treatment for Bruton’s Agammaglobulinaemia?
It can usually be managed by injections of normal human IVIg for life.
What assay is used as the first line test for HIV infection?
ELISA
What antiretroviral drug is given as IV monotherapy during labour to prevent vertical transmission of HIV-1?
Zidovudine
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
What does alpha-1 antitrypsin inhibit?
Neutrophil elastase
Which cell surface receptor allows cells of the innate immune system to bind to immunoglobulins?
Fc receptors
What is the term used to describe a transplant between genetically distinct individuals of the same species?
Allograft
Transplant name between genetically identical members of the same species (self transplant or from an identical twin)?
Isograft
Which cells produce somatostatin?
Delta cells in the pancreas
What viral enzyme is predominantly responsible for the high mutation rate of HIV and other RNA viruses?
Reverse transcriptase
What primary immunodeficiency is a patient with a negative nitro-blue tetrazolium (NBT) test likely to have?
Chronic granulomatous disease
How may mast cell degranulation be measured?
Tryptase level
The paediatric SpR is called to review a 21 day old infant who is pyrexic and appears unwell. His parents are concerned about his florid diarrhoea since birth and an eczema-like rash that has been present since day 3 after birth. He has a fever of 39C. Blood tests reveal a neutrophil count of 8 (normal range: 1.5-8.0), absent T cells and elevated B cells. What primary immunodeficiency is this patient likely to have
X-linked SCID
Which cytokine is important in the pathogenesis of rheumatoid arthritis, anyklosing spondylitis and inflammatory bowel disease?
TNF-alpha
What is the specific antigen recognised by the immune system in Goodpasture’s syndrome?
Type IV collaen
What autoantibody is associated with Granulomatosis with Polyangiitis (Wegner’s Granulomatosis)?
c-ANCA
What autoantibody is associated with Microscopic Polyangitis?
p-ANCA
What is the causative agent of Progressive Multifocal Leukoencephalopathy?
John Cunningham virus
What can cause JV virus re-activation?
This rare complication of immunosuppression is a concern particularly with the monoclonal antibody natalizumab used in the treatment of relapsing remitting multiple sclerosis. The pathogenesis of the condition includes the uncovering of dormant JC (John Cunningham) Virus, which is normally suppressed by a functioning immune system.
How long before skin prick testing must antihistamines be stopped to allow for accurate interpretation?
48 hours
Skin prick testing is used to detect what?
Used to determine allergens in Type 1 (IgE mediated) Hypersensitivity reactions, such as allergic rhinitis.
When is Patch testing used?
Used for the diagnosis of Type 4 (T cell mediated) hypersensitivity reactions, such as contact dermatitis.
What is the gold standard for diagnosis of food allergy?
double-blind, oral food challenge test.
