Short Answer Questions. Answer all questions. Time allowed 1 hour.

There are 10 marks for each question

1)            Parathyroid hormone has a plasma half life of 3 minutes.  A patient undergoing a parathyroidectomy had an initial plasma value of 137 ng/L.  What was the level 11 minutes after isolation of the gland?  How long until the PTH level was undetectable? (Limit of detection = 5ng/L)

(5 marks each part)

2)              The following results were obtained on venous plasma glucose samples (mmol/L) during an oGTT

Fasting 2 hour Symptoms

Case 1 6.5 12.2 None

Case 2 6.6   7.8 None

Case 3 6.0   7.6 None

Case 4 6.9 15.0 Polyuria/Polydipsia

Case 5 6.1   7.7 None

Interpret the results in the light of the WHO criteria.

( 2 marks each)

3)            Define hypoglycaemia.  List 8 possible causes of hypoglycaemia in adults

(2 marks & 8 marks)

4)      Assuming the salt XCl₂ is completely dissociated in water and a 19g/L solution gave an osmolality of 600 mosmol/kg estimate the molecular weight of XCl₂

(10 marks)

5)      What volume of a stock glucose solution containing 9.01 g/L of glucose in saturated benzoic acid (5g/L) would be needed to make a litre of 8.33 mmol/L working standard?  What would be the concentration in g/L of benzoic acid in the final solution?

(6 marks & 4 marks)

6)     Write down the equation for Beer’s Law in terms of a) % transmission b) optical density.  State the units of any symbols used.

(6 marks & 4 marks)

7)      Calculate the hydrogen ion concentration in nmol/L of solutions of pH 6.9 and 7.6.

(5 marks each)

8)        Describe the current definitions for the metabolic syndrome

(10 marks)

9)  State the risk factors that are currently used to calculate cardiovascular disease risk.

(10 marks)

10)   Given the following patient results calculate the fractional excretion    of sodium:-

• • Serum:Urine
  • Sodium 146 mmol/L 50 mmol/L
  • Potassium    4.2 mmol/L
  • Chloride   94 mmol/L 57 mmol/L
  • Urea   34.4 mmol/L         100 mmol/L
  • Creatinine 450 umol/L   3.2 mmol/L
  • Osmolality 337 mmol/kg 325 mmol/kg

10 marks)

                          

Short Answer Questions.

Answer all questions.

Time allowed 1 hour.

A maximum of 10 marks will be awarded for each question

1. The transmittance of a solution of NADH at 340nm is 45%.  What is the absorbance of a 1 in 10 dilution of this solution?
2. List  the porphyrias that may present with acute attacks.
3. Name the enzyme that catalyses the rate limiting step of haem          synthesis and the product.
4. A radioisotope has a half life of 20 days.  What percentage of the initial activity is remaining after 10 days and 7 weeks?
5. A Family Doctor telephones for advice about results on a 24 year          old woman with anorexia nervosa. Serum results were:-

• • Sodium          141 mmol/L
  • Potassium     4.3 mmol/L
  • Urea       4.0 mmol/L
  • Creatinine          78 umol/L
  • Urate            37 umol/L  (149-446)
  • Bilirubin        2 umol/L
  • ALP                      73 IU/L (38-126)
  • ALT                 66 IU/L (<56)
  • Iron          6 umol/L
  • Transferrin      4.0 g/L
  • Transferrin saturation   6%
  • TSH                                      2.5 mU/L (0.5 – 4.2)
  • FT4          9.3 pmol/L  (10.8-19.3)
  • FT3          3.1 pmol/L  (3.5 -6.5)

What would you tell him?

1. A diabetic with a 24 hour creatinine clearance of 25mL/min and a serum creatinine of 180 umol/L was found to have an albumin excretion of 25 ug/min.  If the 24 hour urine has a volume of 2000 mL calculate the albumin/creatinine ratio in mg/mmol.
2. An endomysial antibody assay has been reported to have a diagnostic sensitivity of 88% and a diagnostic specificity of 97% for coeliac disease.  What is the probability that a positive result truly indicates coeliac disease in a group of subjects whose pre-test probability of coeliac disease is 1 in 1500?
3. List 5 ways in which Sickle cell disease may present clinically in       adults.
4. What is the pH of a 0.1 M aqueous solution of an acid of pKa = 4.756 in water at 25^oC?  State any assumptions you make.
5. A Family Doctor telephones you to ask advice about a 53 year old woman with hypertension, truncal obesity and abdominal striae.   What diagnosis is most likely and what first line test(s) would you suggest to investigate this potential diagnosis?
6. Calculate the approximate osmolality of an iv solution of dextrose saline containing 3% w/v glucose and 0.5% w/v sodium chloride

                          

Essay Questions. Answer 2 questions only. Time allowed 1 hour 30 minutes.

1. Diabetes mellitus is a genetic disorder.  Discuss
2. Discuss the role of the lab in the support of the Diabetes service.
3. A 58 year old man attends the clinic and is found to have a serum cholesterol = 7.8 mmol/L and triglycerides = 4.2 mmol/L.  Discuss the investigations you would recommend for this patient.
4. Write an essay on the use of electrophoretic techniques for the diagnosis and management of disease.  Include a brief description of the principles of any technique described.

                          

Essay Questions. Answer 2 questions only. Time allowed 1 hour 30 minutes.

1. Describe the basic components of an HPLC system and outline the main applications of this technique in Clinical Biochemistry.
2. Discuss the presentation and investigation of patients with   suspected anterior hypopituitarism
3. Write an essay on Iron Homeostasis.
4. Critically discuss the methods for the detection of point mutations in human genomic DNA

                          

West Midlands Training Course in Clinical Biochemistry & The University of Birmingham

Essay Paper 29th June 2007

Please answer one question from each module.

You will need to pass each module

Module 1

• 1. Discuss the clinical features and laboratory investigation of a patient with hypothyroidism. 
• 2. Critically evaluate the methods used for the measurement of calcium and vitamin D in serum.

Module 2 

1. Write short notes on

a. Serum Lipoprotein (a) [Lp(a)]

b. ischaemia modified albumin

c. The LDL receptor.

2.  Discuss the laboratory investigation of a patient with paraproteinaemia. 

Module 3

1. Discuss critically the methods available for measuring and estimating glomerular filtration rate
2. Discuss the role of the laboratory in the investigation of a patient with a serum sodium of 118 mmol/L.