Download Question 2 : FT

Case 1186: General Medicine SAQs - 5
Authors and Affiliations
Hannah Pham
School of Medicine
University of Adelaide
Acknowledgements:
Dr Josephine Thomas
Dr Eugenie Lim
Dr Jane Conway
Royal Adelaide HospitalThese Short Answer Questions are suitable for those preparing for their End of
Year Examinations.
Case Overview
Learning Objectives
Question 1 : FT
Question Information:
A 70-year-old man with dilated cardiomyopathy (left ventricular ejection fraction 25%) is assessed in the
Cardiology clinic. Today†™s history and examination suggests that he has Class III NYHA heart
failure. His electrocardiogram demonstrates sinus rhythm and prolonged QRS of 150ms. He is on the
following medications: frusemide, enalapril, metoprolol controlled release, digoxin, spironolactone,
atorvastatin, metformin, and salbutamol.
Question:
What additional medication would you consider for this man, to prevent complications of his dilated
cardiomyopathy? (1 mark) Justify your answer. (2 marks)
Choice 1: null Score : 0
Choice Feedback:
Answer
Anti-coagulation (1)
Note: †œwarfarin†• also accepted as an answer for 1 mark
Justification
†¢ This man is on otherwise maximal therapy for his heart failure (1)
†¢ Severe systolic dysfunction (as suggested by his poor ejection fraction of 25%) due to dilated
cardiomyopathy would predispose to the development of mural thrombus. (1) Anti-coagulation at
prophylactic doses would be appropriate to prevent this.
Question 2 : FT
Question Information:
The patient is a 60-year-old man with a long history of heavy alcohol use. He complains of weight loss
of 8kg in 12 months, anorexia, right upper quadrant discomfort, and jaundice.
His blood tests are as follows †“
†¢ Liver function tests: ALT 600U/L [<55], AST 1000U/L [<45], GGT 800U/L [<60], ALP 300U/L [30110], bilirubin 25umol/L [2-24]
†¢ Complete blood examination: Haemoglobin 90g/L [115-155]
†¢ Coagulation profile: INR 1.4 [0.9-1.2]
An abdominal ultrasound from 12 months ago demonstrated a small, cirrhotic liver.
Question:
What laboratory investigation is next most appropriate? (1 mark) Justify your answer. (2 marks)
Choice 1: null Score : 0
Choice Feedback:
Answer
Alpha-feto protein (1)
Justification
†¢ This man†™s alcohol intake is a strong risk factor for hepatocellular carcinoma (HCC). His
current presentation of weight loss, anorexia, abdominal discomfort, and jaundice are red flags that
should prompt further investigation. (1)
†¢ An alpha-feto protein is an appropriate tumour marker that can be ordered initially and in serial
follow-up. (1)
Question 3 : FT
Question Information:
An 85-year-old man is seen in General Practice. He has a past history of type 2 diabetes mellitus
(poorly controlled), partial gastrectomy, and chronic obstructive pulmonary disease.
Over the last 12 months, he has been feeling tired and has been described as †œoff colour†• by his
wife. He is observed to be unsteady on his feet on standing. A neurologic examination of his lower limbs
is performed, which reveals subtle weakness bilaterally and loss of proprioception and vibration sense
equally.
Question:
What laboratory investigation is most likely to demonstrate the underlying cause of this man†™s
problem? (1 mark) Justify your answer. (2 marks)
Choice 1: null Score : 0
Choice Feedback:
Answer
Serum B12 level (1)
Justification
†¢ This man is likely to have a subacute combined degeneration of the spinal cord secondary to B12
deficiency from a pernicious anaemia that eventuated from his partial gastrectomy. (1)
†¢ This would account for his fatigue, pallor, gait disturbance, and findings on neurologic examination
(involvement of the dorsal/posterior columns suggested with loss of proprioception and vibration sense)
(0.5)
†¢ Therefore, a serum B12 level is most appropriate in the context of this presentation. (0.5)
Notes
†¢ It should be noted that his history of poorly controlled Type 2 Diabetes mellitus may confound his
neurologic examination but the finding expected should be of glove-stocking loss.
†¢ Anti-parietal cell antibodies would be inappropriate at this stage. A CBE and blood smear are likely
to reveal macrocytic hyperchromic anaemia.
Question 4 : FT
Question Information:
An 80-year-old man with Parkinson†™s disease is brought to your clinic. He was diagnosed six years
ago on the grounds of a classical resting tremor, rigidity, and bradykinesia. He has been taking
levodopa with carbidopa (Sinemet) twice a day. He now presents with predictable †œwearing off†•
effect. These is also post-dose dyskinesia.
Question:
What modification would you make to his medication regimen? (1 mark) Justify your answer (2 marks)
Choice 1: null Score : 0
Choice Feedback:
Answer
†¢ Smaller, more frequent dosing of levodopa
Justification
†¢ Motor manifestations of advancing Parkinson†™s should be managed with the aim of increasing
either the effect of or the amount of dopamine available (1)
†¢ Prolonged action of dopamine will combat the †œwearing off†• effect that occurs near the end
of his dose, when less dopamine is available
†¢ Mechanism of action of chosen treatment (1)
The
addition of a dopamine agonist will have the effect of agonising dopamine receptors
Controlled
release levodopa will produce a more constant effect that may avoid †œwearing off†•
near the end of dose
COMT
inhibitors work to prevent breakdown of levodopa in the periphery
MAO-B
inhibitors work to prevent breakdown breakdown of dopamine in the central nervous system
†¢ Post-dose dyskinesia would detract from increasing the dose of levodopa/carbidopa
†¢ Wearing off effect prompts increased frequency of dosing
†¢ Increase in the dose of levodopa/carbidopa will worsen post-dose dyskinesia
Question 5 : FT
Question Information:
An 80-year-old man with Parkinson†™s disease is brought to your clinic. He was diagnosed six years
ago on the grounds of a classical resting tremor, rigidity, and bradykinesia. He has been taking
levodopa with carbidopa (Sinemet) three times a day at near maximal dose. He now presents with
predictable †œwearing off†• effect.
Question:
How would you manage his medication regimen? (1 mark) Justify your answer. (2 marks)
Choice 1: null Score : 0
Choice Feedback:
Answer
†¢ Combine levodopa with a dopamine agonist OR
†¢ Levodopa CR OR
†¢ Smaller, more frequent dosing of levodopa OR
†¢ COMT (catechol-O-methyl transferase inhibitor) (entacapone) OR
†¢ MAO-B inhibitor (selegiline)
Note: any of the above are acceptable at this level for 1 mark.
Justification
†¢ Motor manifestations of advancing Parkinson†™s should be managed with the aim of increasing
either the effect of or the amount of dopamine available (1)
Note: should give rationale for treatment eg, increase effect or of amount of dopamine available
†¢ Prolonged action of dopamine will combat the †œwearing off†• effect that occurs near the end
of his dose, when less dopamine is available
†¢ Mechanism of action of chosen treatment (1)
The
addition of a dopamine agonist will have the effect of agonising dopamine receptors
Controlled
release levodopa will produce a more constant effect that may avoid †œwearing off†•
near the end of dose
COMT
inhibitors work to prevent breakdown of levodopa in the periphery
MAO-B
inhibitors work to prevent breakdown breakdown of dopamine in the central nervous system
Question 6 : FT
Question Information:
A 35-year-old man with a long-standing history of fatigue and abdominal pain has been referred to your
haematology clinic with the following blood results:
†¢ Iron studies
Iron
36 [11-27]
Transferrin
29 [20-40]
Transferrin
saturation 90% [15-55]
Ferritin
1050 [30-500]
†¢ Liver function tests: ALT 600U/L [<55], AST 500U/L [<45], GGT 600U/L [<60], ALP 300U/L [30110], bilirubin 25umol/L [2-24]
†¢ Fasting blood glucseo level 10.5 mmol/L
On examination, there is skin pigmentation over the upper back, fullness in the right upper quadrant of
the abdomen, and bilaterally small gonads.
Question:
What is the most likely diagnosis? (1 mark) Justify your answer. (2 marks)
Choice 1: null Score : 0
Choice Feedback:
Answer
Hereditary haemochromatosis (1)
Justification
†¢ Liver fibrosis (biopsy will be required to confirm), pancreatic insufficiency (diabetes mellitus), skin
pigmentation and hypogonadism would suggest an infiltrative cause of this man†™s presentation (1)
†¢ His iron overload due to hereditary haemochromatosis is the most likely cause. (1)
†¢ Haemochromatosis (HFE) gene testing may help to elucidate this, although no gene mutation is
found in 1 out of 3 cases.
†¢ Venesection would be the required treatment.
Question 7 : FT
Question Information:
A 30-year-old woman presents with acute onset of painful right eye movements in all directions. Her left
eye is normal. This is her first episode. There is no history of trauma. She describes †œblurry†•
vision with †œflickering†• in her peripheral visual field. She denies headache, neck pain, or speech
disturbance. She has had weakness in both her legs, which was noticed two days ago after a hot
shower. Her bladder and bowel continence are intact. A fundoscopic examination of the right eye
demonstrates optic disc swelling.
Question:
What diagnostic investigation is most appropriate? (1 mark) Justify your answer. (2 marks)
Choice 1: null Score : 0
Choice Feedback:
Answer
MRI brain (0.5)
Additional 0.5 marks if specifies:
†¢ MRI orbits
†¢ MRI spinal cord or
†¢ MRI with gadolinium contrast
Justification
†¢ This woman is describing features of optic neuritis, the most likely cause of the visual disturbance
in this case. The bilateral leg weakness may be accounted for by transverse myelitis. Uhthoff
phenomenon would also appear to be present - worsening of symptoms of demyelinating disorders
from heat or exercise. The main concern is an underlying diagnosis of multiple sclerosis. (1)
†¢ As this is her first episode, she does not fulfil McDonald†™s criteria for †œdissemination in
time†•. A gadolinium-enhanced MRI scan will provide information about †œdissemination in
space†• with the presence of plaques (1)
Notes
†¢ Another consideration that must be made is neuromyelitis optica, given the weakness may be
accounted for by transverse myelitis. A serum NMO-IgG antibody may be useful in this case.
Question 8 : FT
Question Information:
A 40-year-old man from Vietnam presents to the chest clinic two months following initiation on antituberculous therapy. He has been on rifampicin, isoniazid, pyrazinamide, and ethambutol for two
months. His initial chest X-ray demonstrated cavitating lesions.
Question:
What is the most appropriate investigation to assess effectiveness of his treatment? (1 mark)
Choice 1: null Score : 0
Choice Feedback:
Answer
Sputum (0.5) for microscopy, culture, and sensitivity (MCS), Ziel nelson stain, Acid fast bacilli (0.5)
Notes
†¢ Sputum MCS should be performed at 2 months to guide continued treatment with anti-tuberculous
agents.
Question 9 : FT
Question Information:
A 40-year-old man from Vietnam has been seen at the chest clinic for the last two months for active
tuberculosis. He has been on rifampicin, isoniazid, pyrazinamide, and ethambutol for two months. The
repeat sputum culture is positive for Mycobacterium Tuberculosis organism. His initial chest X-ray
demonstrated cavitating lesions.
Question:
How does these findings change the management of the continuation phase of his therapy? (1 mark)
Choice 1: null Score : 0
Choice Feedback:
Answer
Continuation phase should be extended to 7 months (0.5) instead of 4 months with 2 anti-tuberculosis
agents (0.5)
Justification
†¢ Cavitating pulmonary lesions and ongoing positive sputum culture 2 months after initial phase or if
the initial phase didn†™t include PZA warrants extending the duration of the continuation phase up to
7 months.
†¢ A longer duration is required to overcome a persistent infection that would not otherwise respond
to a shorter course.
Question 10 : FT
Question Information:
A 50-year-old woman with a history of multiple myeloma presents with gradual onset of generalised
weakness. Her neurologic examination is non-specific with power 4/5 in most movements, but normal
reflexes, coordination, and sensation.
Her blood tests demonstrate the following:
†¢ K 2.0mmol/L [3.5-4.9]
†¢ Cl 114mmol/L [100-109]
†¢ Na 138mmol/L [137-145]
†¢ Bicarbonate 12mmol/L [22-32]
†¢ Mg 0.78mmol/L [0.75-0.95]
†¢ pH 7.20 [7.35-7.45]
The urine chemistry demonstrates presence of glucose, amino acids, and phosphate.
Question:
What is the underlying cause of this presentation? (1 mark)
Choice 1: null Score : 0
Choice Feedback:
Answer
Type 2 renal tubular acidosis (Fanconi syndrome) or Renal tubular acidosis or Tubular absorption
defect (1)
Notes
†¢ Her history of multiple myeloma is a risk factor for Fanconi syndrome.
†¢ Coupled with a low HCO3- with urinary losses of glucose, amino acids, and phosphate is in fact
suggestive of a proximal tubular absorption issue.
†¢ This woman†™s most striking abnormality is her low K+, which can be attributed to many causes.
The low HCO3- in her serum is likely due to failure of reabsorption by her proximal tubular cells. Low K+
differentiates type 1 and 2 RTA from type 4, the latter in which a high K+ would be expected.
Synopsis
Recommended learning outcomes from this set of General Medicine SAQs include:
1. Dilated cardiomyopathy
2. Hepatocellular carcinoma
3. Subacute combined degeneration of the spinal cord
4. Parkinson's (advancing) treatment
5. Hereditary haemachromatosis
6. Multiple sclerosis
7. Tuberculosis monitoring of treatment
8. Tuberculosis treatment regimens
9. Renal tubular acidosis