The University of Sheffield School of Medicine
THE UNIVERSITY OF SHEFFIELDSCHOOL OF MEDICINE
LEVEL 5 INTEGRATED EXAMINATION - SHORT ANSWER QUESTION PAPER MODEL ANSWER QUESTION 1
A previously healthy 29 year old man presents having vomited bright red blood on one occasion, 2 hours earlier.
• What is the differential diagnosis?
• What factors in the history and examination are particularly important?
• Outline the acute and longer-term management of your patient, including a description of the factors which affect your choice of treatment.
Differential diagnosis
A candidate should be expected to know that the most likely diagnosis, given the history, is oesophageal mucosal tear i.e. Mallory-Weiss tear as a result of violent vomiting Other possible causes are:
• acute erosive gastritis, oesophagitis, duodenitis
• bleeding duodenal ulcer
• bleeding gastric ulcer A candidate is expected to give at least one of the above as a diagnosis
Rarer/more unlikely causes in a previously healthy 29 year old male include:
• bleeding oesophageal varices (alcoholic or congenital liver disease)
• gastric carcinoma
• arteriovenous malformation
• rare tumours (e.g. smooth muscle tumours)
« bleeding from elsewhere e.g. swallowed blood from epistaxis
• bleeding diathesis
• anticoagulant drugs
If any of the above appear in the differential, a candidate would be expected to acknowledge its likelihood.
History and Examination
Candidates are expected to direct the answer towards:
• establishing the extent of the volume loss
• confirming the most likely cause and excluding other possibilities
Therefore, in the history:
• extent of acute alcohol ingestion
• repeated and/or violent vomiting preceding the bleed
• dietary excess with food
• syncope
• dyspepsia, dysphagia. acid brash, epigastric pain
• previous haematemesis, malaena
• ingestion of aspirin, non-steroidal anti-inflammatories
• anticoagulant therapy
« smoking
• recreational drug use
• long-term abuse of alcohol
• previous liver disease
• weight loss
fn the examination:
• haemodynamic stability - blood pressure (including postural drop), pulse rate,
JVP, pallor, clamminess etc « abdominal examination - tenderness, particularly epigastric, rebound, guarding, mass,
succussion splash
• malaena per rectum
« signs of chronic liver disease - spider naevi, Dupuytren's contracture, ascites, hep ato splenomegaly, liver flap
Acute .Management
• venous access with large bore cannula +/- central access if indicated
• fluid/plasma expander (e.g. Gelofusin) replacement if signs of hypovolaemia « full blood count, group and save +/- cross-match and transfuse if indicated (shock -*-/-haemoglobin less than lOg/dl)
• U&E, bicarbonate, LFTs, albumin, calcium (milk alkali)
• clotting screen
• admit - medical -*-/- high dependency/ITU if indicated by clinical condition
• control vomiting
• catheterise if shocked
• arrange upper gastrointestinal endoscopy - following day if stable, emergency of re-bleeds, +/- sclerotherapy if oesophageal varices
• helicobacter - breath test, biopsy
• nil by mouth, regular observations, including urine output
• rarely require laparotomy
Longer-term management
• acute alcohol - patient education/counselling
• aspirin, NSAIDs - patient education, change therapy as appropriate
• H2 blockers, proton pump inhibitors
• helicobacter - eradication therapy
THE UNIVERSITY OF SHEFFIELDSCHOOL OF MEDICINE
LEVEL 5 LNTEGRATED EXAMINATION - SHORT ANSWER QUESTION PAPER MODEL ANSWER QUESTION 2
A group of surgeons are keen to set up a screening programme for colorectal cancer. What are the criteria that should be considered before such a programme is introduced?
Minimum requirements - candidates must know the basic principles of a screening programme i.e. that it aims to detect and thus treat patients in a latent or preclinical phase and by doing so, achieve better results in terms of morbidity and mortality than treating in a clinical phase. Candidates should make some specific reference to colorectal cancer in their answer and if they do not do so, they should receive no more than a grade 3.
Wilson and Jungner principles:
1. The condition sought should be an important health problem
2. There should be an acceptable treatment for patients in whom the disease is found
3. Facilities for diagnosis and treatment should be available
4. There should be a recognised latent, pre-clinical or early symptomatic phase
5. The natural history of the condition should be adequately understood
6. There should be a suitable test or examination
7. The test or examination should be acceptable to the population
8. There should be an agreed policy on whom to treat as patients
9. The cost of case-finding (including diagnosis and subsequent treatment) should be economically balanced in relation to the possible expenditure as a whole
10. Case-finding should be a continuous process rather than a 'once for all' project
Coloiectal cancer:
1. Colorectal cancer is the second most common cause of cancer death and is frequently diagnosed at a stage when treatment is less likely to be curative. Overall incidence is increasing.
2. Earlier diagnosis and treatment (surgery) is more effective (5 year survival overall is 50%, 5 year survival early diagnosis is over 90%). Treatment is acceptable, although there are quality of life issues associated with colostomy.
3. Considerable expansion of existing facilities would be required.
4. Polyps (adenomas) are recognised as pre-malignant or pre-invasive phase.
5. Most if not all carcinomas arise from adenomas. Whether all adenomas have malignant potential is controversial. Risk increases with size and histological type (villous greater than tubular). Precise mechanism underlying malignant change in adenoma still uncertain). Could be length-bias i.e. detection and treatment of cases with low malignant potential.
6. Screening for faecal occult blood (FOB). Sensitivity (false positives), specificity (false negatives), positive predictive value etc. Flexible sigmoidoscopy and colonoscopy are not acceptable for population screening, only for at-risk groups.
7. Approximately two-thirds of people offered the test accept. Requirement to collect stool samples deters some.
8. This is the main problem with colorectal cancer screening. If all patients with adenomas detected by screening are followed up with colonoscopy (as per current protocols), the service would be overloaded.
9. Cost-effectiveness is still controversial.
10. Performance of screening in initial round is different than in subsequent rounds (lead-time bias) i.e. prevalent cases detected. Detection in subsequent rounds of incident cases only rnav render screening less cost-effective.
THE UNIVERSITY OF SHEFFIELDSCHOOL OF MEDICINE
LEVEL 5 INTEGRATED EXAMINATION - SHORT ANSWER QUESTION PAPER MODEL ANSWER QUESTION 3
A 58 year old building worker complains of left-sided pleuritic chest pain and worsening exercise intolerance for a period of three weeks. He is a life-time cigarette smoker.
• What is the differential diagnosis?
• What physical signs would you try to elicit?
• How would you investigate your patient?
Differential diagnosis
• lung cancer with malignant effusion (MB patient is a smoker and has a three week history)
• infection - lobar pneumonia, bronchopneumonia, tuberculosis
• asbestos-related pleural disease e.2. mesothelioma (in view of his work)
• pulmonary embolism
• musculo skeletal injury - sprain, fractured rib
• metastatic malignancy (lungs or ribs) « pneumothorax
Physical signs
• general signs relating to infection - fever, tachypnoea, pulse, BP, respiratory distress
• general signs relating to neopiasia - clubbing, evidence of weight loss, lymph nodes etc
• respiratory signs - cyanosis, trachea! shift, chest expansion, air entry, dullness to percussion, pleural rub, bronchial breathing
Investigations
• Routine blood tests - full blood count for anaemia (malignancy), leucocytosis
(infection) « Chest X-ray - masses, pneumonia, pleural disease (include left lateral)
• Blood cultures if indicated (fever)
• Arterial blood gases, especially if cvanosed or in respiratory distress
• Simple lung function tests (FEVh FVC, peak flow)
• CT/Ultrasound, particularly if pleural effusion present
• Bronchoscopy for neopiasia - bronchial cytology, biopsy
• Sputum for microscopy, culture and sensitivity - pneumonia
• Sputum for cytology for lung cancer - low sensitivity
• If pleural effusion - fluid for cytology, culture +/- biopsy
• If DVT/pulmonary embolism suspected - Doppler studies calves, V.'Q scan, D dimer blood test, spiral CT
• Serology for atypical pneumonia
THE UNIVERSITY OF SHEFFIELDSCHOOL OF MEDICINE
LEVEL 5 INTEGRATED EXAMINATION - SHORT ANSWER QUESTION PAPER MODEL ANSWER QUESTION 4
You are asked to see an 80 year old patient who has had an emergency sigmoid colectomy 1 week previously for perforated diverticular disease. The nurse is concerned about the patient's observations which are:
urine output of less than IQml/hour for four hours;
central venous pressure of 15cmH^O;
blood pressure 110/60;
pulse 90bpm;
temperature 39.5°C.
• What is the differential diagnosis?
• What management would you instigate?
Differential diagnosis
The patient has a fever and evidence of hypovolaemia (hypotension, tachycardia, decreased urinary output) and the likeliest scenario is infection leading to septicaemia and shock. However, the CVP is raised indicating a degree of right heart/congestive cardiac failure. This patient is likely to have a combination of disorders rather than any single diagnosis. Students who do not comment about the significance of a raised CVP should not be given more than a grade 3. Possible sites of infection are:
• chest infection
• anastomotic leak with peritonitis or abscess
• wound infection
• urinary tract infection +/- urinary retention Pulmonary embolism is also possible Myocardial infarction should be considered
Management
• General examination - shock
• Respiratory examination - chest expansion, air entry, percussion note, pulmonary oedema
• Cardiovascular examination - cardiac failure
• Abdominal examination including PR - wound infection, tenderness, rebound, guarding, pelvic abscess
• Blood, urine, wound swab, sputum (if available) before commencing antibiotics -
microscopy, culture and sensitivity » FBC - icucocytosis
• U&E - hydration, renal failure. LFTs.
• CXR,ECG
• Examine legs - signs of deep venous thrombosis
• Screen for disseminated intravascular coagulation
Depending on examination and initial investigations:
• venous access - resuscitation as necessary
• treat with broad spectrum IV antibiotics after specimens taken for microbiology -
directed at anaerobes and coliforms (e.g. cefotaxime and metronidazole) « Gastrografin enema - anastomotic leak - urgent laparotomy after resuscitation
US or CT abdomen - subphrenic or pelvic abscess
blood gases - oxygen if indicated
catheterisation
monitor CVP and urine output
manage on High Dependency Unit/Intensive Care Unit as indicated by general condition
referral to renal physicians/cardiologists if renal function,'cardiac function deteriorating
Doppler studies calves, V/Q scan, spiral CT, D dimer blood test if DVT/PE suspected
THE UNIVERSITY OF SHEFFIELDSCHOOL OF MEDICINE
LE\TL 5 INTEGRATED EXAMINATION - SHORT ANSWER QUESTION PAPER MODEL ANSWER QUESTION 5
A 65 year old man is admitted following a confirmed myocardial infarction. He was making an uneventful recovery from the acute episode, but on the 6th day after infarction he collapsed and could not be resuscitated. A post-mortem was performed.
• What would you expect to see in the heart at post mortem?
• What other pathology might be present to account for his sudden death?
Wltat would you expect to see in the heart at post mortem?
• the infarction should be clearly established - yellow/white area with intensely red
border
• there may be mura] thrombus
• there should be atherosclerosis in at least one of the three main branches of the coronary arteries with or without thrombosis
• very occasionally, there will be no atherosclerosis or thrombosis - MI secondary to spasm
• there may be localised pericarditis +/- a small pericardia! effusion
At this stage folio wins acute myocardial infarction, one would not expect to see fibrosis/scarring and/or a ventricular aneurysm, unless of course the patient has had a previous infarction. Even if present, aneurysms occurring as a result of previous MI rarely if ever rupture.
What other pathology might be present to account for his sudden death?
• the infarcted area may have involved the conducting system leading to fatal arrhythmia
• myocardial infarction affecting septum - rupture leading to septal defect
• myocardial infarction affecting a papillary muscle - rupture leading to acute mitral incompetence
• myocardial infarction affecting the free wall of the ventricle - rupture leading to haemopericardium and cardiac tamponade
• pulmonary embolism - may or may not find associated deep vein thrombosis
• although the patient may have had a cerebral infarct as a result of embolism from mural thrombosis, this would not be visible at this stage. However, you may see embolus hi the cerebral circulation
• cerebral haemorrhage - if present would probably be related to anticoagulant therapy
• pneumonia - but unlikely as a cause of sudden death in a patient making an otherwise uneventful recovery
Candidates who offer ventricular aneurysm or cardiac failure as a cause of death should probably not be graded higher than 3, as neither is likely as a cause of sudden death, 6 days post-Mi.
THE UNIVERSITY OF SHEFFIELDSCHOOL OF MEDICINE
LEVEL 5 LNTEGRATED EXAMINATION - SHORT ANSWER QUESTION PAPER MODEL ANSWER QUESTION 6
What method, if any. would you employ as prophylaxis against deep vein thrombosis in
the following patients? Explain your reasoning. What complications may occur as a
result of your treatment?
• A 65 year old male who is to undergo oesophagogastrectomy.
« A 72 year old female who is to undergo total hip replacement.
Oesophagogastrectomy is high risk because:
• major surgery lasting longer than 40 minutes
• chest and abdominal incision
• usually done for cancer
Total hip replacement is high risk (60% DVT without prophylaxis) because:
• major surgery lasting longer than 40 minutes
• location of surgery
• immobility before and after surgery
Therefore, both these operations are high-risk although it could be argued that THR is the higher risk.
Therefore, both:
• Low molecular weight heparin (Enoxaparine, Clexane) 40mg s/c once daily, 1st injection 12 hours prior to surgery. Continue for 7-10 days of until patient mobilised. (NB Patients thought to be at high risk should be given 40mg, patients at moderate risk 20mg s/c od.
• Unfractionated heparin 5000 bd/tds was the standard regime but is not adequate
• unfractionated heparin in an adjusted dose regime, monitoring APPT is acceptable, but very difficult
• warfarin not effective
• Hirudin (recombinant leech protein, direct thrombin inhibitor) has a product licence for use in knee and hip surgery and there is now evidence that is better but more expensive than LMW heparin.
• TED (graduated) stockings
» Flowtron compression pump during anaesthesia (oesophagogastrectomy)
• positioning during surgery
• early mobilisation
Complications
• failure in one third - DVT +/- PE requiring therapeutic anticoagulation
• spontaneous bleeding
• bruising and bleeding at injection and operation sites
• heparin-induced thrombocytopenia after 5 days - serious complication
• hypersensitivity
• alopecia
• osteoporosis - but only after prolonged treatment and therefore not relevant here
THE UNIVERSITY OF SHEFFIELDSCHOOL OF MEDICINE
LEVEL 5 LNTEGRATED EXAMINATION - SHORT ANSWER QUESTION PAPER MODEL ANSWER QUESTION 7
A 34 year old woman presents with a few months' history of recurring rash, arthraigias and alopecia. More recently, she noticed haematuria and pedal oedema. Investigation showed renal function to be impaired with a raised serum creatinine (250 iiniol/1) and a 24 hour protein excretion of 6.5g.
• What is the most likely diagnosis?
• Describe the underlying pathogenesis of the symptoms and signs?
• How would you confirm the diagnosis?
• What other investigations would you undertake?
• How would you manage this patient?
Most likely diagnosis
• Systemic lupus erythematosus with renal involvement (aephrotic/nephritic)
Underlying pathogenesis
• autoimmune condition
• autoantibodies to nuclear components
• complement deficiency
• Type III hypersensitivity (immune complex mediated)
• Immune complex deposition in small vessels giving rise to generalised vasculitis particularly affecting skin, joints and kidneys (glomerulonephritis)
Confirmation of diagnosis
• antinuclear antibodies
• anti-dsDNA
• C3,C4
Other investigations
• possible renal biopsy preceded by clotting studies for lupus anticoagulant
• full blood count - Hb, WCC (for cytopenias)
• skin biopsy if rash present
• urine microscopy
• anti-ENA (for prognosis)
• creatinine clearance or isotope glomeruiar filtration rate
• CXR - cardiac size, lung fields
Management
• refer to rheumatoiogist +/- renal physician
• immunosuppression
• steroid (methylprednisolone) initially high dose (3 x 500mg on consecutive days reducing to low dose according to response (0.75-lmg/kg)
• cyclop ho sphamide if not pregnant or intending to be pregnant
• or azathioprine Img/kg increasing if tolerated to 2.5mg/kg
• or cyclosporin A
• ?hydroxychloroquine
• ?plasma exchange
when stable response, monitor monthly using BP, urinalysis, C3, C4 dsDNA
monitor for side-effects - bone marrow suppression, opportunistic infection
if renal function deteriorates - dialysis may be required
continue treatment for more than 1 year even if asymptomatic and inactive serology
THE UNIVERSITY OF SHEFFIELDSCHOOL OF MEDICINE
LEVEL 5 INTEGRATED EXAMINATION - SHORT ANSWER QUESTION PAPER MODEL ANSWER QUESTION 8
What antibiotics, if any, would you use as prophylaxis in the following operations? Explain your reasoning. How long would you treat the patients for? What other means may be taken to reduce post-operative infection?
• An 18 year old female who underwent aortic valve replacement as a child because of congenital abnormality and who is to undergo extraction of wisdom teeth.
Decisions concerning antibiotic prophylaxis are a function of the risk associated with the given cardiac lesion and the risk associated with the given surgical procedure. This patient is at high risk of endocarditis because:
• aortic valve replacement (risk lOOx or so normal)
• type of surgery - mouth major source of the (gram positive) bacteria (viridans streptococci) likely to cause endocarditis
• dental procedure - associated with bleeding Therefore:
• amoxycillin
• best evidence - 3g orally before and 6 hours after
• IV (Ig) pre-op, (O.Sg) orally 6 hours post-op
• if allergic to penicillin, Clarithromycin (?vancomycin)
• ?gentamicin (120mg) Other means of reducing infection risk:
• optimise dental care in high risk patients
• minimise trauma to gum tissues at time of surgery
• A 70 year old female who is to undergo total hip replacement.
Post-operative prosthetic joint infections (PJI) are associated with the development of wound infections or infected haematoma post-op eratively, which may often be sub-clinical but which may ultimately require the prosthesis to be removed. Most likely pathogens are skin pathogens, predominantly Staphylococci and Streptococci
• cefazolin or other first generation cephalosporin Ig pre-op eratively and tid IV for 24-48 hours
• cefuroxime (2nd generation cephalosporin) is less effective against the likely organisms but is used locally 750mg IV pre-op and for 3 doses 24-48 hours