Self assessments Flashcards
The presence of right ventricular dilatation and thinning combined with arrhythmias in a young man should automatically raise the suspicion of
arrhythmogenic right ventricular cardiomyopathy
Inheritance of arrhythmogenic right ventricular cardiomyopathy
autosomal dominant inheritance pattern
Complication of arrhythmogenic right ventricular cardiomyopathy
sudden death
Which condition is described: myocardium shows replacement by fibro-adipose tissue predominantly but not exclusively affecting the right ventricle?
arrhythmogenic right ventricular cardiomyopathy
Which part of the heart does Hypertrophic obstructive cardiomyopathy effect?
Left ventricle
Asymmetric hypertrophy of the septum is characteristic of…
Hypertrophic obstructive cardiomyopathy
Dilated cardiomyopathy primarily affects….
the left ventricle
tendon xanthomata on both Achilles tendons
pathognomonic of Familial hypercholesterolaemia
Underlying defect in FH
Mutation in the LDL receptor
Genotype associated with Familial dysbetalipoproteinaemia and lipid levels in blood.
Apo E2/E2 genotype is associated with Familial dysbetalipoproteinaemia (cholesterol and triglycerides elevated)
Increased hepatic synthesis of VLDL occurs in
Familial Hypertriglyceridaemia and causes predominantly increased triglycerides
Causes of Familial Chylomicronaemia
Lipoprotein lipase deficiency and Apo C-II deficiency ( associated with predominantly raised triglycerides)
Weight loss in a water deprivation test (due to water loss) is consistent with
diabetes insipidous
What normally happens to the osmolality of urine in response to water deprivation?
Increases (gets more concentrated)
A 35-year-old surgeon has a red, scaly itchy rash on both hands. The rash improves when he changes the type of glove he wears when operating. He has no history of asthma, rhinitis or eczema and is generally in good health. His only known allergy is to kiwi fruit. What is the most likely diagnosis of the rash?
Allergic contact dermatitis
There is cross-reactivity between latex and a number of foods including bananas, avocado and kiwi fruit.
popliteal and/or antecubital fossae rash
Atopic allergic eczema
What’s the optimum treatment for anaphylaxis?
Lie flat and give Intramuscular epinephrine (adrenaline)
Corticosteroids have a role in reducing the possibility of a late reaction occurring.
Which chemical mediator form pain?
Prostaglandin and bradykinin
Signs of inflammation
calor (warmth)
rubor (erythema)
tumour (swelling)
dolor (pain)
Common causes of raised triglycerides
Obesity
Excessive alcohol intake
Hypothyroidism (predominantly raised LDL and total cholesterol but triglycerides can also be raised)
Cholestasis lipid profile
raised LDL and total cholesterol but triglycerides are usually normal
Lipid profile of Familial Hypercholesterolaemia
high plasma total cholesterol and LDL concentrations
A 49-year-old female presents with joint and muscle pains lasting for a few weeks and general malaise. On examination she is found to be hypertensive and to have peripheral sensory and motor neuropathy. Further investigation reveal areas of renal infarction. Nerve biopsy demonstrates transmural inflammation of medium sized arteries with fibrinoid necrosis and frequent neutrophil polymorphs. Which of the following findings is most likely in this patient?
polyarteritis nodosa (PAN)
What is polyarteritis nodosa (PAN) associate with?
(approximately 30%) may be associated with infection with Hepatitis B
What size vessels does PAN affect?
medium-sized vessels
Examples of ANCA positive small vessel vasculitides
microscopic polyangiitis – p (MPO) ANCA
Wegeners granulomatosis or Granulomatosis with polyangiitis – c (PR3) ANCA
Churg-Strauss syndrome – p (MPO) ANCA
Vasculitis associated with Hep C
Cryoglobulinaemic vasculitis
A 75-year-old retired teacher is found to have mild to moderate pancytopenia, with a mild macrocytosis (large red cells). His general practitioner checks his vitamin B12 and folate, liver function and thyroid function, but finds no abnormality. The patient is on no medications and is teetotal. A bone marrow sample shows hypercellularity and abnormal maturation of red cell and granulocyte precursors, but no excess of blasts. What is the most likely diagnosis?
Myelodysplasia
What can myelodysplasia progress to?
acute myeloid leukaemia
A 6-year-old girl is taken to see her general practitioner because her mother is concerned about her almost continuously scratching the skin in her antecubital and popliteal fossae. There are numerous excoriations at these sites with some superficial secondary infection. She is otherwise very well. Both her parents have severe hayfever during the summer. What is the most likely diagnosis?
Atopic allergic eczema
Gluten sensitivity skin rash
dermatitis herpetiformis
Areas of skin affected by dermatitis herpetiformis
skin overlying extensor surfaces of joints
Sites that scabies affects
web spaces between the fingers and toes, palms and soles, wrists and axillae
A 48-year-old engineer has an eight month history of worsening fatigue, malaise, fevers and splenomegaly. A blood count shows a mild anaemia and markedly elevated white cell count (120 x10^9/l), comprising an excess of mature and maturing myeloid granulocytes. What is the most suitable next investigation?
PCR for the BCR-ABL fusion gene
or FISH for the BCR-ABL fusion gene
or cytogenetic analysis for the Philadelphia chromosome
CML chromosome abnormality
t(9;22) BCR-ABL philadelphia chromosome
Upper limit of white cell count in reactive neutrophilias
rarely exceed 30 x10^9/L
Antibiotics that have anti-pseudomonal activity
- piperacillin-tazobactam (Tazocin®)
- certain cephalosporins (e.g ceftazidime but not cefotaxime)
- some carbapenems (e.g. meropenem, but not ertapenem)
- aminoglycosides (e.g. gentamicin)
- quinolones (e.g. ciprofloxacin).
Can co-amoxiclav be used against pseudomonas?
No
Metronidazole activity
anaerobic bacteria (and some protozoa, e.g. Giardia lamblia)
When can vancomycin be used?
Vancomycin (a glycopeptide antibiotic) is active against the cell wall of most Gram positive bacteria, but its large molecular size prevents it penetrating the outer membrane of Gram negative organisms - against which it is almost universally inactive.
What causes the majority of mitral stenosis?
rheumatic heart disease
Most common cause for aortic stenosis
‘senile calcific aortic stenosis’
Risk factor for right-sided valve disease?
IV drug use
A 47 year old woman attends her GP with a short history of malaise, and mouth ulcers.
The GP notices some petechiae on her arms and legs, and a small blood blister in her mouth. She has a fever of 38.1C, and some crackles at the left lung base.
A blood count performed on a ‘point-of-care’ instrument in the GP surgery shows pancytopenia. Her neutrophil count is 0.2 x10^9/l.
What is the most appropriate course of action?
Immediate referral to hospital for admission and intravenous broad spectrum antibiotics
However, her treatment pathway is clear: febrile neutropenia is a medical emergency, and patients can deteriorate rapidly in the absence of appropriate treatment. She should be admitted to hospital for immediate broad spectrum antibiotics (e.g. tazocin). Further investigation can proceed as an inpatient.
Clinical features of neonatal meningitis
Clinical features of infection are often very non-specific in neonates, and focal signs of infection (e.g. signs of meningeal irritation in meningitis) are often absent. Clinical assessment therefore often depends heavily on the results of laboratory and other investigations.
Causes of neonatal meningitis
Group B streptococci and enterococci
Who does meningococcus affect?
Neisseria meningitidis (meningococcus) are Gram negative cocci; meningococcal meningitis usually occurs in older children.
A 69 year old man is being investigated for splenomegaly. He has a mild anaemia, a normal white cell count, and a normal platelet count. His blood film, however, is highliy abnormal, being reported as showing:
“Variation in red cell size and shape, with frequent teardrop poikilocytes, and some nucleated red cells. Some immature granulocytes are seen, but there is no significant blast population.”
A Calreticulin gene mutation is detected by PCR.
What is the most likely diagnosis?
Myelofibrosis
Cell of origin of myelofibrosis?
Megakaryocyte precursor
Classic picture of myelofibrosis
anaemia and splenomegaly - and the spleen can become massively enlarged.
Teardrop poikilocytes are red cells which are distorted into a teardrop shape; they are often seen when the normal architecture of the marrow is disrupted by fibrosis, or metastatic disease
The combination of immature granulocytes plus nucleated red cells in the peripheral blood is known as
a ‘leucoerythoblastic film’
A ‘leucoerythoblastic film’ occurs in the context of…
marrow infiltration, fibrosis or, very severe sepsis - any situation where the marrow is attempting to respond to great stress
Mutations associated with myelofibrosis
JAK2 (58%)
CALR (calreticulin) (25%)
MPL (7%)
T cell response time course
Days
acute symptoms in the morning and evening are typical of…
Mast cell triggering by allergen (probably grass pollen first thing in the morning and early evening and house dust mite during the night) cross-linking mast cell bound IgE with immediate release of mediators such as histamine.
What type of vaccine is the pneumococcal vaccine included in the current UK childhood immunisation programme?
Polysaccharide conjugate vaccine
A 20 year old man is admitted to hospital with unwell with a fever. He is tachycardic and hypotensive, and resuscitation with fluids is commenced pending further investigations. Shortly after admission his conscious level falls and he becomes unresponsive. An urgent cranial CT shows an intracerebral haemorrhage. A blood count gives the following results:
Hb 76 g/L, WBC 0.5x10^9/L, and platelets 43 x10^9/L. A blood film shows a population of myeloid blasts with very heavy granulation. Coagulation studies suggest disseminated intravascular coagulation
Which of the following most accurately describes his disease?.
Acute promyelocytic leukaemia
This disease arises due to a translocation between chromosomes 15 and 17 and produces the fusion gene PML-RARA. This results in failure of maturation at a specific stage of myeloid development - the promyelocyte. The heavy granulation is characteristic of this. These granules contain procoagulant materials and their release can cause disseminated intravascular coagulation (DIC - of which more later in the course). This in turn can result in catastrophic bleeding in the presentation of these patients.
Immediate hypersensitivity is tested using
Skin prick test
What’s an Arthus reaction?
intradermal injection of an antigen takes hours to develop
What’s the Mantoux test?
test for reaction to tuberculin is a delayed hypersensitivity reaction mediated by T cells and macrophages and takes several (2-7) days to evolve
What’s pathergy?
The presence of pathergy (test for Behcet’s disease) would manifest as a pustule at both the test and negative control sites.
Pathergy is a skin condition in which a minor trauma such as a bump or bruise leads to the development of skin lesions or ulcers that may be resistant to healing. Pathergy can also lead to ulcerations at the site of surgical incisions. Pathergy was seen with both Behçet’s disease and pyoderma gangrenosum.
What’s Behcet’s disease?
Behçet’s disease (BD) is a type of inflammatory disorder which affects multiple parts of the body. The most common symptoms include painful mouth sores, genital sores, inflammation of parts of the eye, and arthritis
A 17 year old man has a history of frequent, severe respiratory tract infections since childhood. He also suffers from malabsorption with steatorrhoea. His lungs have bronchiectasis. Which diagnosis is most likely to explain all his symptoms?
Cystic fibrosis
A 21-year-old woman is admitted to hospital complaining of tingling in her fingers and toes. She is due to sit her University Final exams and has recently been suffering from attacks of anxiety. Arterial blood gas analysis shows:
pH 7.53 (reference interval 7.35-7.45);
pCO2 3.5 kPa (4.5-6 kPa);
HCO3- 25 mmol/L (24-30 mmol/L).
What is the most likely diagnosis?
Hyperventilation
What causes tingling in hyperventilation?
The tingling is due to reduced ionised calcium concentration, secondary to the alkalosis.
Clinical investigation for a PE?
CT pulmonary angiography (CTPA)
A 35-year-old man presents with persistently raised blood pressure. His general practitioner has tried several anti-hypertensive agents but there has been no improvement. Arterial blood gases show metabolic alkalosis and hypokalaemia. What is the most likely diagnosis?
Primary hyperaldosteronism
Primary hyperaldosteronism is also known as….
Conn’s syndrome
What causes hypertension but does not alter the acid/base balance?
Acromegaly
Likely blood gas in renal failure
metabolic acidosis
How would you test for influenza viruses?
Throat swab for immunofluorescence
Influenza viruses infect the upper and lower respiratory tract, from which they may be isolated by throat swab or nasopharyngeal aspirate (NPA). Cells from the throat swab or NPA are then ‘spotted’ onto a slide and stained with fluorescein-labelled monoclonal antibodies against influenza. The virus is detected by direct visualization using a fluorescence microscope.
Latex agglutination is used to detect….
pathogen specific antibodies (usually in serum) by observing whether they agglutinate latex particles coated with pathogen specific antigens.
Word meaning that a bacteria can be acquired from animals
ornithosis
Chlamydophila psittaci is associated with…
birds
Treatment for Chlamydophila psittaci
doxycycline
Examples of non-zoonotic causes of atypical pneumonia in humans and the treatment
Legionella pneumophila
Mycoplasma pneumoniae
Chlamydophila pneumonia
macrolide
Pneumocystis jiroveci is associated with…
HIV
A 25 year old student presents with malaise and a fever. He is found to be pancytopenic, though occasional large very primitve looking cells are seen on his blood film. A bone marrow shows that 35% pf the nucleated cells in his marrow are blasts, some of which contain sparse granules. What is the mostly likely diagnosis?
Acute myeloid leukaemia
That these blasts are granulated suggests acute myeloid leukaemia, though immunophenotyping could be used to clarify this if there is doubt. Remember that chronic myeloid leukaemia is one of the myeloproliferative neoplasms and would present with an excess of mature and maturing myeloid cells - not the pancytopenia seen here.
Diagnostic criterion for acute leukaemia
> 20% blasts in the bone marrow
A 54-year-old female presents with symptoms of right-sided pneumonia and unintentional weight loss. She also has a history of recurrent pleural effusions. She has never smoked. Chest X-ray reveals a 4 cm irregular peripheral mass abutting the pleural surface. Fluid aspirated from the right pleural cavity shows numerous highly pleomorphic cells some of which contain intra-cytoplasmic mucin. The cells are positive for epithelial markers on immunohistochemistry.
What is the most likely diagnosis?
Adenocarcinoma
What’s the most common lung carcinoma in non-smokers?
Adenocarcinoma
Lung cancer associated with EGFR activating mutations? What can you treat with?
adenocarcinomas
EGFR tyrosine kinase inhibitors, such as gefitinib or erlotinib
Where are squamous cell carcinomas usually positioned?
central
Squamous cell carcinomas are associated with…..
Smoking and thought to arise from areas of squamous metaplasia.
Where do small cell carcinomas usually arise?
hilar bronchus
What are lung hamartomas and how are they diagnosed?
Lung hamartoma is a relatively common benign lesion, which is usually discovered as an incidental rounded and well circumscribed focus on routine chest X-ray (coin lesion). The majority are peripheral, solitary and less than 3 cm in diameter.
CURB65. What’s it used for and what are the criteria?
Risk of death at 30 days of patients with CAP
Confusion Urea >7 mmol/l Respiratory rate >30/min Blood pressure (systolic BP<90 or diastolic BP≤60 mmHg) Age ≥65 years
A 73-year-old former shipyard pipe fitter presents with a 3 year history of progressive shortness of breath. His lung function tests show a restrictive picture. He eventually dies of respiratory failure. What are the likely postmortem finding in his lungs?
Honeycomb lung with scattered asbestos fibres
Which lung condition is associated with Extensive fibrosis with centrilobular emphysema?
coalworker’s pneumoconiosis in addition to coal macules
Which lung condition is associated with Fibrotic nodules with refractile particles?
silicosis
Which lung condition is associated with Panlobular emphysema with lower lobe predominance
alpha-1 antitrypsin deficiency
Which phase of anaphylaxis are eosinophils associated with?
delayed phase
Time course for T cell immune reactions
Days rather than minutes
What’s the most common cause of a serious respiratory illness in infancy?
Bronchiolitis
Pathogenesis of bronchiolitis
Inflammation of the narrow bronchioles in these children leads to partial blockage and thereby distal collapse or hyperinflation of lung tissue.
Most common cause of child bronchiolitis
~80% cases the cause is respiratory syncytiovirus (RSV), and the diagnosis can be confirmed by detection of RSV in nasopharyngeal aspirates by immunofluorescence, ELISA, or PCR
Causes of bronchiolitis
RSV
human metapneumovirus
parainfluenza viruses
human bocavirus
“Bronchial walls show basement membrane thickening with smooth muscle hypertrophy and the presence of numerous eosinophils.” What is the most likely diagnosis?
Acute allergic asthma
‘diffuse alveolar damage with hyaline membrane formation’ is characteristic of….
adult respiratory distress syndrome
A 24-year-old man who is otherwise in good health has a red, itchy, scaly rash affecting both hands. He works as a builder. The rash cleared up when he was away on a 4 week holiday but re-occurred on returning to work. He underwent skin testing to help identify the cause of his problem. When would be the optimal time to read the test?
2 to 7 days after the start of the test
This man probably has allergic contact dermatitis (chromates in cement are a not uncommon cause). Thus the skin test employed is most likely to be patch testing, a form of delayed hypersensitivity skin test. A solution of test antigen is applied as a ‘patch’ to the skin surface (usually on the back) along with a negative control. The test is usually read between 2 and 7 days later when a positive reaction would manifest as a patch of dermatitis at the site of application of the antigen.
How long should you wait for a Heaf or Mantoux test?
2-7 days
How does the IGRA work?
The interferon gamma release assay (IGRA) works by looking for a specific T-cell response to antigens from M. tuberculosis: T-cells that have previously been exposed to the antigens respond by releasing interferon gamma which can be measured by an ELISA (there are 2 commercial assays available; one uses a standard ELISA, the other an ELISPOT - essentially a modified ELISA in which the ‘footprint’ of individual interferon gamma secreting T-cells can be visualized as dots under the microscope). The IGRA is thus a test for TB infection, but cannot distinguish latent TB infection (LTBI) from active TB disease.
How should you treat latent TB
The most common regimen for LTBI treatment is isoniazid monotherapy for 6 months (an alternative is a combination of isoniazid plus rifampicin for 3 months).
Blood gas and anion gap for renal tubular acidosis
metabolic acidosis but with normal anion gap
How can you biopsy for peripherial lung masses?
a percutaneous (through the skin) needle biopsy approach is most likely to yield a diagnosis
This procedure is typically performed under CT guidance in order to ensure that the lesion is not missed.
