Chem_Path_2_Flashcards
An obese 35 year old patient has the following results:
* 9am cortisol (Monday): 650 nM
* Given 0.5 mg dexamethasone every 6 hours for 48 hours
* 9am cortisol (Wednesday) 500 nM
What is the diagnosis?
e. Cushing’s syndrome of indeterminate cause
79) 9 year old boy brought in. He is fitting. Glucose 1.9 mmol/L. Insulin 205 mu/L. C-peptide <33 pmol/L.
What is the most likely cause of the low blood glucose?
What should be done next?
Sampling from the pituitary (IPSS)
What is the best measure of kidney function?
Glomerular filtration rate
Which factor(s) limit(s) the use of serum creatinine as a marker of GFR?
It is related to muscle mass
A spot urine measurement to quantify proteinuria can be done instead of a 24 hour urinary collection. Is this true or false?
True
Which of the following is true regarding urine dipstick testing?
You can reliably exclude bacteriuria if the urine dipstick is negative for nitrites
You admit a 28 year old man who you suspect has a renal stone, what is your first choice of imaging?
CT KUB
Which class of drugs may predispose patients to developing pre-renal AKI?
All of the above
A 68 year old man with previously normal renal function is found to have a creatinine of 624μmol/l. Renal ultrasound shows the following appearance in both kidneys. What is the likely cause of his AKI?
Benign prostatic hypertrophy
Patient with dark urine + bruising has new onset AKI. What is likely diagnosis?
Rhabdomyolysis
A 40 year old female presents with a rash and AKI is diagnosed. What is the most likely cause of her renal failure from the following list?
Systemic vasculitis
What two measures do we use to define AKI?
Creatinine and urine output
Regarding hyperkalaemia, which of the following is true?
It can lead to ECG changes such as peaked p waves and flattened t waves.
Your patient with CKD has been started on an ESA but does not respond. What could be the cause?
Any of the above
The following are contraindications to transplantation - True or false? HIV positive, BMI >30, Active sepsis, Aged >65yo, Any malignant disease
False, False, True, False, False
Which of the following commonly presents with depression?
Uraemia
What will histology of bone in a patient with hyperparathyroidism show?
Brown tumours made up of multinucleate giant cells
What is an enzyme?
A substance (usually a protein) that increases the rate of a chemical reaction without itself being changed in the overall process.
What is Km?
Substrate concentration at which reaction velocity is 50% of maximum.
Which of these tissues make alkaline phosphatase (ALP)
All of the above
A 40 yo man presents with abdominal pain. The serum ALP is elevated. What tissue is the ALT most likely coming from?
Liver
What occurs first in response to hypoglycaemia
Suppression of insulin
C-peptide:
is the cleavage product of insulin, is secreted in equimolar amounts to insulin
Hypoglycaemia due to excess injected insulin would result in..
A low C-peptide
20 year old female, BMI 16 kg/m2. Lanugo hair noted. Finger prick glucose – 3.8mmol/L. Routine bloods taken. Doctor rung by lab 1 hr later as plasma glucose 2.6 mmol/L. What is the most likely cause of her low blood sugar?
Poor liver glycogen stores
What would the insulin and C-peptide result be if they had been measured?
Low insulin, low C-peptide
1 day old neonate - jittery, not-feeding. Premature (34 weeks gestation). Lab glucose 1.9 mmol/L. Glucose improved on feeding, but low blood glucose 4 hours after feed. 3-hydroxybutyrate measured at time of hypo and was negative. What is 3-hydroxybutyrate?
A ketone body
What does the absence of ketones signify (glucose 1.9, ketones negative)?
Fatty acid oxidation defect
45 year old lady admitted fitting. Recurrently seen GP in previous months due to weight gain and increased appetite. Husband reports personality change in last few months. Glucose 1.9 mmol/L. Insulin 35 mu/L. C-peptide 1000 pmol/L. What is the diagnosis?
Insulinoma
9 year old boy brought in. He is fitting. Glucose 1.9 mmol/L. Insulin 205 mu/L. C-peptide <33 pmol/L. What is the most likely cause of the low blood glucose?
Factitious insulin
60 year old cachectic man found unconscious. Smoker. Glucose 1.9 mmol/L. Hypoglycaemia persists – glucose infusion. Insulin and C-peptide undetectable. Free fatty acids – undetectable. Ketones negative. What is the likely diagnosis?
Non-islet cell tumour hypoglycaemia
What is the common blood test that best indicates acute liver dysfunction?
Prothrombin time
In purine metabolism:
All of the above
In the treatment of gout: 2 CORRECT ANSWERS
NSAIDs are the first line treatment in acute attacks, Allopurinol lowers urate levels by inhibiting xanthine oxidase
What is this?
Negatively birefringent urate crystal
What is this?
Positively birefringent pyrophosphate crystal
A 19yo man returns from holiday in Spain. Four weeks later, he develops a hot, swollen, painful red knee joint with an effusion. The knee is tapped and 20ml of cloudy yellow fluid is withdrawn. Microbiology reveals gram negative intracellular diplococci. What is the organism?
Neisseria gonorrhoeae
A 19yo student arrives in casualty, septic, pyrexial (39 degrees Celsius) and confused. He has a stiff neck and LP reveals gram negative intracellular diplococci.
Neisseria meningitidis
A 6yo boy arrives in casualty, septic, pyrexial (39 degrees Celsius) and confused. He has a stiff neck and LP reveals gram negative rods.
Haemophilus influenzae
A 19yo student arrives in casualty, septic, pyrexial (39 degrees Celsius) and confused. Blood cultures grew gram positive diplococci.
Streptococcus pneumoniae
A 19yo student arrives in casualty, septic, pyrexial (39 degrees Celsius) and confused. Blood cultures fail to culture any organisms. Cold agglutinins are positive.
Mycoplasma pneumoniae
A 19yo student has a boil on his leg which is 2cm in diameter and painful. It is drained and some of the pus sent to microbiology. Eventually, it grows gram positive cocci in clusters.
Staphylococcus aureus
A 19yo has a mild fever for several months and no cause can be found. After 2 months, blood cultures come back positive for gram positive cocci.
Streptococcus viridans (infective endocarditis)
30yo man has polyuria and polydipsia. Fasting blood glucose is 4.7. Raised calcium, low phosphate, normal PTH. What is the diagnosis?
Primary hyperparathyroidism
50yo Asian woman complains of tingling in her hands and feet. When checking her blood pressure, her hand reveals carpal spasm. Fasting blood glucose is 4.9. Low calcium, normal phosphate, high PTH. What is the diagnosis?
Secondary hyperparathyroidism
50yo Asian woman complains of nocturia and dizziness. Fasting blood glucose is 3.9. Low sodium, high potassium, high calcium, normal phosphate, normal PTH. What is the diagnosis?
Addison’s disease
60yo man complains of pain in his knee and examination reveals an effusion. Withdrawal of fluid and microscopy reveals crystals, which on viewing under polarised light are positively birefringent. What is the diagnosis?
Pseudogout
Which condition occurs in Lesch-Nyhan syndrome?
Acute gout
Which condition occurs in patients with osteomalacia?
Secondary hyperparathyroidism
30yo man complains of polyuria and polydipsia. Fasting blood glucose is 4.7. High sodium, normal potassium, normal calcium, normal phosphate, normal PTH. What is the diagnosis?
Diabetes insipidus
During acute porphyria, the most useful sample to send is:
Urine
Cutaneous erythema without blisters or bullae most likely indicates:
Erythropoietic protoporphyria
Hyponatraemia associated with AIP is due to:
SIADH
Urine samples taken during an acute attack of porphyria for diagnosis should be
Protected from light
