Clinical Chemistry Lecture CUMULATIVE

MLS 4410

Patients with hyperaldosteronism often exhibit:

Hypokalemia

Which of the following test aids in the diagnosis of cystic fibrosis when genetic testing is inconclusive?

Chloride sweat test

The body works to maintain a _ ratio between bicarbonate and carbonic acid.

20:1

Patients on insulin therapy should be closely monitored for which of the following electrolytes:

Potassium

A patient’s hypokalemia may be mild or subclinical. Physicians often suggest these patients to treat their hypokalemia with which of the following?

Bananas, beef, spinach, potatoes

Patients are at risk for cardiac arrest when their potassium levels are nearing:

7.0 mmol/L

In vitro hemolysis can result in which of the following?

Falsely elevated potassium

Which organ is primarily responsible for controlling the level of CO₂ in the blood?

Lungs

HCO₃ is best described as which of the following?

Base

Which of the following does not play a primary role in maintaining the acid-base balance in the body?

Vitamin D

What is the most abundant extracellular cation?

Sodium

A sample that is yielding a falsely decreased calcium value and a falsely increased potassium value is the result of what?

EDTA contamination in heparinized plasma

With increased water loss, burn patients are most likely to also experience:

Hypernatremia

PTH and 1,25 (OH)2D are the principal hormones involved in the normal physiologic regulation of homeostasis of what?

Calcium

Which of the following is a complication of hypercalcemia?

Kidney stones

Which of the following has an inverse relationship with calcium?

Phosphate

The measurement of which of the following analytea utilizes an ion-selective electrode?

Ionized calcium

A patient’s calcium level is 5.3 mg/dL. How should this be interpreted?

Critically low

When arterial blood from a patient with normal values is exposed to room air:

pCO2 will be falsely decreased, pO2 will be falsely increased.

What is the first line of defense against acid/base imbalance?

Physiologic buffers

A decreased affinity for oxygen means that the RBC will…

Release oxygen into tissue

What is the most common cause of metabolic acidosis?

DKA

Partially compensated acidosis results in…

Normal pH

A patient’s anion gap is decreased. Which of the following is most likely?

Instrument error

The overall effect of parathyroid hormone (PTH) release is to:

Increase bone reabsorption

All of the following statements about partially compensated respiratory alkalosis are true except:

The causative defect is hypoventilation.

CHF (congestive heart failure) is known to cause…

Hypervolemic hyponatremia

In patients that are symptomatic due to a calcium imbalance caused by primary hyperparathyroidism, which of the following is common?

Tetany

The role of aldosterone is to actively cause the reabsorption of…

Potassium

The role of aldosterone is to actively cause the secretion of…

Sodium

How should a laboratory verify the reference range it uses for a particular test?

Test samples from healthy people

Which of the following is the primary compensation for respiratory acidosis?

Renal acid excretion

Which of the following is not implicated in high metabolic gap metabolic acidosis?

Hypoventilation

Severe diarrhea causes:

Metabolic acidosis

The specimen of choice for a total calcium analysis is…

Heparinized serum

Secondary hyperparathyroidism is often the result of:

Renal disease

In acidosis, which of the following analytes will increase?

Free calcium

The parent substance for all steroid hormones is:

Cholesterol

The urinary excretion product measured as an indicator of epinephrine production:

Vanillylmandelic acid

Gout is characterized by accumulation of what in the joints?

Uric acid

In creatinine clearance, 1.73 is used to:

Normalize clearance by making it independent of muscle mass

John Doe’s lab results are as followed. His chemistry profile is indicative of what?

BUN: 12 mg/dL

CREA: 1.5 mg/dL

Uric acid: 60 g/dL

Gout

Secretion of hormones by the anterior pituitary is controlled by circulating levels of hormones from the target gland and the:

Hypothalamus

Which of the folllowing is a tropic hormone?

FSH

ACTH secretion is inhibited by high levels of:

Cortisol

Which of the following is secreted by the posterior pituitary gland?

ADH

A 11-year old patient is found to have mildly elevated alkaline phosphatase. This is…

Normal for growing children

Which of the following is most affected by hemolysis?

Lactate dehydrogenase

Which of the following is most specific for acute pancreatitis?

Lipase

Following an MI, which of the following increases most?

AST

The greatest source of CK is:

Skeletal muscle

Unconjugated bilirubin in the bloodstream is bound to:

Albumin

The enzyme that conjugates bilirubin in the hepatocyte is:

UDP-glucuronic aminotransferase

Which stage of chronic kidney disease has been subdivided into two stages to reflect GFR and renal function?

III

A patient with GFR of 10mL/min/1.73m² would be considered in which stage of CKD?

V

Impetigo caused by GAS would likely lead to which of the following?

Acute glomerulonephritis

A specimen collected for the measurement of ammonia can be collected and processed in the same manner as a specimen collected for a serum creatinine measurement.

False

Which of the following is most at risk for an initial diagnosis of gout?

60-year old man

All of the following are true about serum creatinine except:

Decreased levels indicate CKD.

In clinical practice, GFR is routinely estimated by the determination of serum creatinine. If more exact data are needed, ___ is used.

Creatinine clearance

An increasse in cortisol levels is defined as:

Cushing’s

Hirtsuism is a clinical manifestation of:

Addison’s

The action of a ___ hormone is specific for another endocrine gland:

Tropic

Hypothalamic/pituitary disease is a ___ cause of Addison’s disease.

Secondary

Which of the following is an adrenal cortical hormone?

Aldosterone

Primary adrenal insufficiency requires demonstration of:

Impaired response to ACTH stimulation

Which of the following is the most sensitive liver enzyme for excessive alcohol consumption?

GGT

Enzyme reactions measured in a clinical setting are most commonly measured using:

Zero-order kinetics

Lipase is more specific than amylase for the diagnosis of what?

Acute pancreatitis

Labor is stimulated by an artificial form of which of the following?

Oxytocin

Which of the following is not a tropic hormone secreted by the anterior pituitary gland?

Growth hormone

Thyroid hormones are synthesized from which amino acid?

Tyrosine

Another name for primary hyperaldosteronism is…

Conn’s syndrome

Patients with Addison’s disease can present with all the following except:

Hypernatremia

Acute intermittent porphyria (AIP) patients have a deficiency of:

PBG-deaminase

Zinc protoporphyrin measurements are useful to assess blood concentrations of:

Lead

Which of the following is likely to occur first in iron deficiency anemia?

Decreased serum ferritin

Which of the following proteins binds ferric iron and is increase in IDA?

Transferrin

The majority of the iron in whole blood is:

Bound to hemoglobin

The majority of absorbed lead is taken up by __ and inhibits heme synthesis:

Erythrocytes

Maple syrup urine disease is characterized by an increase in valine, leucine, and isoleucine due to a decrease or absence in:

Alpha-ketoacid decarboxylase

The best treatment for aminoacidopathies like PKU is an…

Decreased protein diet

When measuring AA concentrations in plasma, it is recommended that the patient be…

Fasting

Which of the following is a tumor marker for hepatocellular carcinoma?

Alpha 1-fetoprotein

What protein concentration is often low in Wilson’s disease?

Ceruloplasmin

Which cardiac marker is elevated the longest period after myocardial infarction (MI)?

Troponin T

Which isoenzyme of CK is primarily found in cardiac muscle?

MB

Which of the following cardiac markers is the first to increase after an acute myocardial infarction?

Myoglobin

Which MI marker is the most specific and sensitive and remains elevated for 14 days or more?

TnT

The SGOT test is another name for analyzing…

AST

Which liver enzyme is most significantly affected by specimen hemolysis?

LDH

Which liver enzyme is most closely associated with liver damage due to alcohol consumption?

GGT

A patient with mumps has elevated amylase. How should this be interpreted?

Caused by parotitis from mumps

An individual comes into the emergency room with a crush injury. Which enzyme would be significantly increased?

CK

A hallmark of which aminoacidopathy is the formation of crystals and stones in urine:

Cystinuria

Transthyretin is also known as…

Prealbumin

A deficiency in this protein increases the risk of emphysema:

Alpha 1-antitrypsin

A pregnant woman at 32 weeks gestation’s vaginal secretions have fFN. What does this indicate?

Pre-term labor

Which of the following albumin:globulin ratio would be considered normal?

1.2

Which of the following conditions is indicated by presence of Bence-Jones proteins?

Multiple myeloma