Clinical Chemistry Lecture Exam IV

MLS 4410

Which of the following is the metabolism of glucose molecules to pyruvate or lactate for production of energy?

Glycolysis

Which of the following is the formation of glucose from noncarbohydrate sources?

Gluconeogenesis

Which of the following is the breakdown of glycogen to glucose for the use of energy?

Glycogenolysis

Which of the following is the conversion of glucose to glycogen for storage?

Glycogenesis

Which of the following directly converts the original substance to energy?

Glycolysis

In IDDM, sodium levels are typically _ and potassium levels are _, while NIDDM typically has levels that are _.

Low, high, normal

The classic triad of type 1 diabetes is:

Polyphagia, polydipsia, polyuria

Urine specific gravity of a person with diabetes mellitus is typically:

High

Urine specific gravity for a person with diabetes insipidus is typically:

Low

Glycosuria occurs once plasma glucose is above what?

180 mg/dL

A 25 year-old healthy female patient complains of dizziness and shaking one hour after eating a large, heavy-carbohydrate meal. The result of a random glucose test performed was 60 mg/dL. What does this indicate?

Hypoglycemia

A nurse taking care of diabetic patients performed a fingerstick glucose test and obtained a value of 200 mg/dL. A plasma sample, collected at the same time, resulted in a glucose value of 225. Explain the discrepancy.

The discrepancy is not significant because results of whole blood specimens are lower than plasma/serum values.

Which of the following hormones promotes gluconeogenesis?

Hydrocortisone

Glucose oxidase oxidizes glucose to gluconic acid and…

H2O2

What is the preferred specimen for glucose analysis?

Sodium fluoride plasma

In a grey-top tube, the sodium fluoride serves to inhibit…

Glycolysis

A patient is being assessed for lactose intolerance. The baseline BGL was 82 mg/dL and their second was 80 mg/dL. How should this be interpreted?

The patient is lactose intolerant.

Hyperglycemic factor produced by the pancreas is…

Glucagon

The preferred screening test for diabetes in non-pregnant adults is measurement of:

Depends on patient factors

A factor, other than average plasma glucose values, that can affect HbA1c level is:

Red blood cell life span

Monitoring the levels of ketone bodies in the urine is:

Recommended for patients with T1D on sick days

A urinalysis identifies a positive result for reducing sugars, yet the dipstick was negative for glucose. Of the following, which is most likely?

Galactose-1-phosphate uridyltransferase deficiency

High levels of C-peptide indicates what?

Insulinoma

Which of the following is used to assess patients in septic shock?

Lactic acid

Which of the following is not a reducing sugar?

Sucrose

What is the difference between an aldose and a ketose?

Aldoses have a terminal carbonyl, while ketones have one linked to two other carbons.

Which of the following hormones is not antagonistic to insulin?

Estrogen

A 24-hour urinalysis of glucose level is performed by reduction using what metal?

Copper

Which form of diabetes is defined as a relative insulin deficiency?

NIDDM

What is a triglyceride?

Three fatty acids, one of which is glycerol

Which of the following lipoproteins is visible with the naked eye?

Chylomicrons

Trans fats are quickly converted to which lipoprotein?

LDL

Which apolipoprotein activates lipoprotein lipase to break down triglycerides?

Apo C

Pancreatic lipase cuts off fatty acids and bile salts aggregate around to form…

Micelles

A 40 year-old man was diagnosed with hyperlipidemia at 13 years old after his father — who was 34 at the time — died of an MI. His grandfather also died of an MI while he was 43 years old. His lipid panel results are below. Which of the following diagnoses fits best?

Triglycerides: 91 mg/dL

Total cholesterol: 269 mg/dL

HDL: 47 mg/dL

LDL: 204 mg/dL

Familial hypercholesterolemia

A 49 year-old woman was referred for a lipid evaluation by her dermatologist after she developed xanthomas over her trunk. She has no family history of a lipid disorder or CHD. She is post-menopausal and on hormone-replacement therapy. Her lab results are below. How should they be interpreted?

Serum: Grossly lipemic

Triglycerides: 6200 mg/dL

Total cholesterol: 458 mg/dL

Fasting glucose: 160 mg/dL

Liver function: Normal

Hyperlipoproteinemia

Which of the following statements concerning chylomicrons is false?

Mainly transports triglycerides

Several enzymatic triglyceride methods measure the production or consumption of:

Glycerol

The most likely cause for serum/plasma to appear “milky” is the presence of…

VLDL

What is the presumed defect in most cases of familial hypercholesterolemia?

Defective receptors for LDL

Which of the following hormones increases plasma glucose levels by inhibiting the entry of glucose into muscle cells?

Growth hormone

Which of the following is an example of secondary diabetes?

Pancreatic cancer

DKA is most common in which form of diabetes?

Type I

Which of the following would be diagnostic of diabetes?

HbA1c of at least 6.5% confirmed on repeat measurement

An elevated value of which of the following analytes in the urine of diabetic patients indicates kidney damage - likely a result of diabetic nephropathy.

Microalbumin

A patient presents to the out patient lab for a blood draw for a fasting blood sugar level at 7am, Monday morning. The patient mentions having had a late night snack of fig newtons around 1am. What is the best course of action for the phlebotomist to take?

Standard requests are for a 10-12hr fast. Since the patient does not meet this criteria, ask them to wait and contact the physicians office and ask how to proceed.

Which of the following lipid results would be expected to be falsely elevated on a serum specimen from a non-fasting patient?

Triglycerides

VLDL transports:

Endogenous triglycerides

As part of a hyperlipidemia screening program, the following results were obtained on a 25 year old woman 6 hours after eating. Which of the following is the best interpretation of these results?

Triglycerides: 260 mg/dL
Cholesterol: 120 mg/dL

Cholesterol is normal but triglycerides are falsely elevated.