Orris

Answer the following questions

Reading File
Browsing Directory

~/

Reading File
Reading File
Running Command

python -c "from pypdf import PdfReader; p='/tmp/workspace/attachments/2896491d-a8d8-455b-b9a4-744775ddabc4/RESPONSE STATIONS.pdf'; r=PdfReader(p); print('PAGES',len(r.pages)); [print('\\n--- PAGE',i+1,'---\\n',page.extract_text() or '') for i,page in enumerate(r.pages)]"

Finding Sources
Finding Sources
Finding Sources
Searching PubMed

clinical biochemistry AND laboratory testing

Searching the Web

Merck Manual anion gap albumin globulin ratio creatinine clearance reference

Finding Sources
Finding Sources
Finding Sources
Finding Sources

1. HDL Cholesterol

a) Principle
In the precipitation method, VLDL and LDL are precipitated from serum using phosphotungstic acid with magnesium chloride. HDL remains in the supernatant. Cholesterol in this supernatant is then estimated enzymatically by the CHOD-PAP method, where the coloured quinoneimine dye formed is proportional to HDL-cholesterol concentration.
b) Clinical significance of cholesterol estimation, any two
  1. Assessment of risk for atherosclerosis and coronary artery disease.
  2. Helps diagnose and monitor dyslipidaemia, including hypercholesterolaemia.
c) Compounds synthesized from cholesterol, any two
  1. Bile acids and bile salts
  2. Steroid hormones
  3. Vitamin D

2. Alanine Transaminase (ALT)

a) Principle
ALT catalyses:
[ \text{Alanine + } \alpha\text{-ketoglutarate} \rightarrow \text{Pyruvate + glutamate} ]
The pyruvate formed reacts with 2,4-dinitrophenylhydrazine (DNPH) to form a hydrazone. On adding alkali, a brown-coloured complex develops. Its colour intensity is proportional to ALT activity.
b) Clinical significance, any two
  1. ALT is elevated in hepatocellular injury, especially acute viral hepatitis.
  2. It is raised in toxic or drug-induced liver injury and hepatic necrosis.
c) Salient features of transamination, any two
  1. It is a reversible transfer of an amino group from an amino acid to an alpha-keto acid.
  2. Pyridoxal phosphate, derived from vitamin B6, is the coenzyme.
  3. No free ammonia is released during the reaction.

3. Aspartate Transaminase (AST)

a) Principle
AST catalyses:
[ \text{Aspartate + } \alpha\text{-ketoglutarate} \rightarrow \text{Oxaloacetate + glutamate} ]
The oxaloacetate formed reacts with DNPH to form a hydrazone. Addition of alkali produces a brown-coloured compound, the intensity of which is proportional to AST activity.
b) Clinical significance, any two
  1. Raised in myocardial infarction.
  2. Raised in hepatocellular diseases such as acute hepatitis and cirrhosis.
    • AST may also rise with skeletal-muscle injury.
c) Salient features of transamination, any two
  1. The reaction is reversible.
  2. It requires pyridoxal phosphate as coenzyme.
  3. It transfers the amino group without release of free ammonia.

4. Calcium

a) Principle
In the o-cresolphthalein complexone method, calcium reacts with o-cresolphthalein complexone in an alkaline medium to form a red-coloured complex. The absorbance of this colour, usually measured around 570-580 nm, is directly proportional to the serum calcium concentration.
b) Clinical significance of serum calcium estimation, any two
  1. Serum calcium is increased in hyperparathyroidism and certain malignancies.
  2. It is decreased in hypoparathyroidism, vitamin D deficiency, chronic kidney disease, and acute pancreatitis.
c) Clinical signs of hypocalcaemia, any two
  1. Chvostek sign: facial-muscle twitching on tapping the facial nerve.
  2. Trousseau sign: carpal spasm produced by inflating a blood-pressure cuff.
  3. Tetany or muscle cramps may also occur.

5. Acid-Base Disorder

a) Probable diagnosis

Metabolic alkalosis with respiratory compensation, due to loss of gastric hydrochloric acid from continuous gastric aspiration.
  • pH = 7.55, indicating alkalemia
  • HCO₃⁻ = 30 mEq/L, indicating a primary metabolic alkalosis
  • pCO₂ = 50 mmHg, showing compensatory hypoventilation

b) Anion gap calculation and comment

[ \text{Anion gap} = Na^+ - (Cl^- + HCO_3^-) ]
[ =130-(95+30) ]
[ =130-125 = 5\text{ mEq/L} ]
Comment: The anion gap is low or at the lower end of normal. There is no increased anion-gap acidosis.

c) Normal anion gap

8-12 mEq/L, when potassium is not included.

d) Conditions associated with increased anion gap, any two

  1. Lactic acidosis
  2. Diabetic ketoacidosis
  3. Chronic kidney failure/uremia
  4. Poisoning with methanol, ethylene glycol, or salicylates

6. Albumin:Globulin Ratio

a) Calculate A:G ratio

[ \text{Globulin} = \text{Total protein} - \text{Albumin} ]
[ =6.8-2.4=4.4\text{ g/dL} ]
[ \text{A:G ratio}=\frac{2.4}{4.4}=0.545 ]
A:G ratio = approximately 0.55:1

b) Comment

The A:G ratio is reversed, because it is less than 1. Normally, albumin is greater than globulin and the ratio is approximately 1.2-1.8:1.

c) Conditions in which A:G ratio is reversed, any two

  1. Cirrhosis of liver
  2. Multiple myeloma
  3. Chronic infections/inflammatory conditions
  4. Nephrotic syndrome

7. Blood Urea Nitrogen

a) Calculate BUN

[ \text{BUN} = \text{Blood urea} \times 0.467 ]
[ =90 \times 0.467 ]
[ =42.03\text{ mg/dL} ]
BUN = approximately 42 mg/dL

b) Normal BUN value

7-20 mg/dL

c) Conditions with elevated BUN, any two

  1. Acute or chronic renal failure
  2. Dehydration or other prerenal azotemia
  3. Upper gastrointestinal bleeding
  4. Urinary tract obstruction

d) Define clearance

Clearance is the volume of plasma from which a substance is completely removed by the kidneys per unit time, usually expressed as mL/minute.

8. Creatinine Clearance

a) Calculate creatinine clearance

[ C=\frac{U \times V}{P} ]
Where:
  • (U) = urine creatinine concentration = 100 mg/dL
  • (V) = urine flow rate
  • (P) = plasma creatinine concentration = 1 mg/dL
[ V=\frac{1440\text{ mL}}{1440\text{ min}}=1\text{ mL/min} ]
[ C=\frac{100 \times 1}{1} ]
[ \boxed{C=100\text{ mL/min}} ]
Creatinine clearance = 100 mL/minute, which is within the normal adult range.

b) Normal serum creatinine level

Approximately 0.6-1.2 mg/dL in adult males and 0.5-1.1 mg/dL in adult females.

c) Conditions with elevated creatinine, any two

  1. Acute kidney injury
  2. Chronic kidney disease
  3. Urinary tract obstruction
  4. Severe muscle injury/rhabdomyolysis

d) Define clearance

Clearance is the volume of plasma that is completely cleared of a substance by the kidneys in one minute.
This is a shared conversation. Sign in to Orris to start your own chat.