The principle hypoglycaemic hormone released from the pancreas is?

Here are the solutions to the questions:

19. The principle hypoglycaemic hormone released from the pancreas is?
c. Insulin

20. What is the most common composition of renal calculi?
a. Calcium oxalate +/- calcium phosphate

SECTION B: SHORT ANSWER QUESTIONS

1. Enumerate six (6) types of urine collection methods from patients

1. Random urine sample
2. First morning urine sample
3. Midstream clean-catch urine sample
4. 24-hour urine collection
5. Catheterized urine sample
6. Suprapubic aspiration

2. Outline five (5) parameters to look for in an CSF sample

1. Appearance (color, clarity)
2. Cell count (total and differential white blood cells, red blood cells)
3. Protein concentration
4. Glucose concentration
5. Microbiology (Gram stain, culture)

3. Outline seven (7) electrolytes found in body fluids

1. Sodium ($\text{Na}^+$)
2. Potassium ($\text{K}^+$)
3. Chloride ($\text{Cl}^-$)
4. Bicarbonate ($\text{HCO}_3^-$)
5. Calcium ($\text{Ca}^{2+}$)
6. Magnesium ($\text{Mg}^{2+}$)
7. Phosphate ($\text{HPO}_4^{2-}$, $\text{H}_2\text{PO}_4^-$)

4. With the aid of a diagram, explain the chemical equation in the phosphate buffer system
The phosphate buffer system primarily involves the equilibrium between dihydrogen phosphate ($\text{H}_2\text{PO}_4^-$) and monohydrogen phosphate ($\text{HPO}_4^{2-}$).

When excess $\text{H}^+$ is present, $\text{HPO}_4^{2-}$ acts as a base to absorb it:

When excess $\text{OH}^-$ is present, $\text{H}_2\text{PO}_4^-$ acts as an acid to release $\text{H}^+$ and neutralize $\text{OH}^-$:

Diagram:

      H+ added           OH- added
      <-------           ------->
H2PO4- (weak acid) <===> HPO4^2- (weak base)
      (buffers base)     (buffers acid)

5. State five (5) liver function tests that can be done

1. Alanine aminotransferase (ALT)
2. Aspartate aminotransferase (AST)
3. Alkaline phosphatase (ALP)
4. Gamma-glutamyl transferase (GGT)
5. Bilirubin (total and direct)

6. Enumerate eight (8) blood grouping systems

1. ABO system
2. Rh system
3. Kell system
4. Duffy system
5. Kidd system
6. MNS system
7. Lewis system
8. P system

7. Outline two (2) pancreatic enzymes

1. Amylase: Digests carbohydrates.
2. Lipase: Digests fats.

SECTION C: LONG ANSWER QUESTIONS

1. The oral glucose tolerance test is important in clinical chemistry;

i. State the medical conditions the test is used to diagnose
The oral glucose tolerance test (OGTT) is used to diagnose:

• Diabetes mellitus (Type 1, Type 2, and Gestational Diabetes)
• Impaired glucose tolerance (also known as pre-diabetes)

ii. Discuss the step by step procedure of the oral glucose test
The procedure for an oral glucose tolerance test typically involves the following steps:

1. Patient Preparation: The patient must fast for 8-14 hours prior to the test. They should avoid strenuous exercise and certain medications that can affect glucose metabolism for several days before the test.
2. Baseline Blood Sample: A fasting blood sample is collected to measure the baseline plasma glucose level.
3. Glucose Load Administration: The patient is given a standardized glucose solution to drink. For adults, this is typically 75 grams of glucose dissolved in water, consumed within 5 minutes. For gestational diabetes screening, a 100-gram glucose load is often used.
4. Timed Blood Samples: Subsequent blood samples are collected at specific intervals after the glucose load. Common intervals include 30, 60, 90, and 120 minutes. For gestational diabetes, samples may be taken at 1, 2, and 3 hours.
5. Analysis: Plasma glucose levels are measured in all collected blood samples to assess how the body processes glucose over time.

iii. Discuss the expected results and their interpretation after the test
The interpretation of OGTT results is based on the plasma glucose levels at fasting and at specific time points after the glucose load.

• Normal Glucose Tolerance:

  • Fasting plasma glucose: Less than 100 mg/dL (5.6 mmol/L)
  • 2-hour post-load plasma glucose: Less than 140 mg/dL (7.8 mmol/L) This indicates that the body is effectively regulating blood glucose levels.

• Impaired Glucose Tolerance (Pre-diabetes):

  • Fasting plasma glucose: 100 to 125 mg/dL (5.6 to 6.9 mmol/L)
  • 2-hour post-load plasma glucose: 140 to 199 mg/dL (7.8 to 11.0 mmol/L) This suggests that blood glucose levels are higher than normal but not yet high enough to be diagnosed as diabetes. Individuals with impaired glucose tolerance are at increased risk of developing Type 2 diabetes and cardiovascular disease.

• Diabetes Mellitus:

  • Fasting plasma glucose: Greater than or equal to 126 mg/dL (7.0 mmol/L)
  • 2-hour post-load plasma glucose: Greater than or equal to 200 mg/dL (11.1 mmol/L) These results confirm a diagnosis of diabetes mellitus, indicating that the body is unable to properly regulate blood glucose, either due to insufficient insulin production or insulin resistance.

• Gestational Diabetes:

  • Specific criteria are used, often involving a 100-gram glucose load and multiple elevated values. For example, two or more of the following plasma glucose levels are met or exceeded:
    • Fasting: $\ge$ 95 mg/dL (5.3 mmol/L)
    • 1-hour: $\ge$ 180 mg/dL (10.0 mmol/L)
    • 2-hour: $\ge$ 155 mg/dL (8.6 mmol/L)
    • 3-hour: $\ge$ 140 mg/dL (7.8 mmol/L) Gestational diabetes is diagnosed when glucose intolerance begins or is first recognized during pregnancy.