Exam 1 Review SQ

Question 1

What does QA stand for?

Answer 1

Quality Assessment. QA monitors laboratory testing and reporting accuracy that is continuous and documented to ensure patient safety. Its a criteria of CLIA ‘88 for overseeing labs. The goal is to reduce medical errors and improve patient outcomes

Question 2

What are the components of QA?

Answer 2

*Preanalytical components - before testing
*Analytical components - aspects during testing
*Postanalytical components - procedures and policies that affect reporting and interpretation of results.

Question 3

What is the purpose of proficiency testing?

Answer 3

Its mandated by CLIA 88’. A lab can order a group of specimen for proficiency testing or order it from another lab to do the testing. The lab will do the testing and report results to the other lab to check their results.

Question 4

What is the CDC and what do they do?

Answer 4

Stands for Centers for Disease Control and Prevention. The agency implements public health regulations and reporting requirements for clinical laboratory and other healthcare providers. They’re responsible for categorizing newly developed laboratory tests as waived testing, moderate complexity, and high complexity testing and perform CLIA related studies.

Question 5

What is OSHA and what do they do?

Answer 5

Stands for Occupational Safety and Health Administration. The agency regulates issues of worker safety for the clinical laboratory. Workers have a right to a safe environment and able to report any violates without any retaliation from employers.

Question 6

What is TJC? What do they do?

Answer 6

Stands for The Joint Commission. The organization has the privilege to provide service for the federal government.

Question 7

What is CAP and what do they do?

Answer 7

Stands for College of American Pathologists. It’s a professional organization with the status to provide service for the federal government.

Question 8

What is CLIA 88’?

Answer 8

Stands for Clinical Laboratory Improvement Amendments of 1988. The purpose is to ensure laboratory test results are of high quality regardless of where tests are performed. The law includes mandates for quality control, proficiency testing, quality assessment, external inspections, site visits, consultations, and minimum personnel requirements. It also regulates a lab based on the level of testing it conducts. So if the lab were only doing moderate complexity testing then high complexity testing requirements would not apply.

Question 9

What is waived testing? Give examples.

Answer 9

Used to describe tests approved by the FDA for home use and are designed to minimize testing errors and pose no reasonable risk of harm to patients when performed inaccurately.

Examples can be pregnancy testing, at home glucose blood test, covid testing, and urine dipstick.

Question 10

What is moderate complexity testing? Give examples

Answer 10

Used to describe more difficult to perform than waived tests in the lab. Requires instrumentation calibration, training documentation, proficiency testing, and on site inspection under CLIA 1988. In the hospital setting, both moderate and waived testing must adhere to moderate complexity testing standards.

Instruments from hematology, clinical chemistry, automated or semi automated urinalysis and urine microscopic analysis fall into this category.

Question 11

What is high complexity testing? Give examples.

Answer 11

A term used to describe a test that requires a high degree of interpretative knowledge and skill. It must be performed by more experienced personnel and more complex instrumentation.

Tests performed are usually from the cytology, immunology, immunohematology, microbiology, and molecular diagnostics department.

Question 12

What happens to solutes in urine sitting out at room temperature?

Answer 12

*After 2 hours there is an increase in color, turbidity, pH, nitrite, bacteria, and Oder
*After 2 hours there is a decrease in glucose, ketones, bilirubin, urobilinogen, RBCs, WBCs, and casts.
*The biggest problem is the growth of bacteria as the urine sits out in room temperature.

Question 13

What are criteria for rejecting urine specimens? List as many as possible.

Answer 13

*Specimens in unlabeled containers
*Specimens of insufficient quantity
*No matching labels and requisition forms or no orders in computer
*Specimens that have been improperly transported
*Specimens contaminated with feces or toliet paper
*Labs must have written policies for rejection of specimens
*Using a container with detergent residue or bleach for specimen
*Using urine collected from a bedpan because it may be contaminated with feces
*Urine wrung out of a diaper for UA is not acceptable.

Question 14

What tubes are acceptable for urine culture?

Answer 14

It’s a grey top with boric acid inside. For up to 48 hours at room temperature.

Question 15

What tubes are not acceptable for culture but urinalysis?

Answer 15

 Red Marble yellow top (BD Preservation Tube from Becton Dickinson Rutherford, NJ) for up to 72 hours
 BD Vacutainer for up to 96 hours

Question 16

What is the normal specific gravity of urine?

Answer 16

 1.003 s.g. To 1.010 s.g. For normal
 24 hour collection 1.015 – 1.030 s.g.
 Acidic urine 1.010 or higher

Question 17

How does the nephron concentrate urine?

Answer 17

•First, is the proximal tubule absorbs about 66% of water
•Second is the countercurrent multiplication where the medulla (kidney) and loop of henle use energy to generate an osmotic gradient that enables you to Reabsorbs water from tubular fluid and produce concentrated urine
•Third mechanism is a decrease in sodium, blood volume or blood pressure leads to release of renin which forms Angiotensin II that stimulates secretion of aldosterone by adrenal cortex. Aldosterone activates sodium reabsorption in distal tubule and collecting ducts thereby adjusting lucid volume in body fluids.
•Fourth, is the absorption of water in distal portion (collecting ducts) of nephron that is regulated by ADH. It’s secreted by pituitary gland.

Question 18

Describe how countercurrent multiplication.

Answer 18

countercurrent multiplication where the medulla (kidney) and loop of henle use energy to generate an osmotic gradient that enables you to Reabsorbs water from tubular fluid and produce concentrated urine.

Question 19

What are the four ways the kidneys concentrate urine?

Answer 19

1. Proximal tubule absorbs 66% of water
2. Countercurrent multiplication
3. RAAS system
4. Absorption of water in distal portion and collecting duct if aldosterone is secreted.

Question 20

Describe what each part of the nephron does.

Answer 20

*Glomerulus – Filters small solutes from blood (under 66k daltons)

*Proximal convoluted tubule – Reabsorbs ions, water, and nutrients. It removes toxins and adjusts filtrate pH

*Descending loop of henle – Water absorption, its membrane is permeable to water.

*Ascending loop of henle – Reabsorbs Na+ and Cl- from filtrate into interstitial fluid

*Distal tubule – Selectively secretes and absorbs different ions to maintain blood pH and electrolyte balance

*Collecting duct – Reabsorbs solutes and water from the filtrate

Question 21

Whats absorbed in each part of the nephron?

Answer 21

• Glomerulus – Filters small solutes from blood (under 66k daltons)
• Proximal convoluted tubule – Reabsorbs ions, water, and nutrients. It removes toxins and adjusts filtrate pH
• Descending loop of henle – Water absorption, its membrane is permeable to water.
• Ascending loop of henle – Reabsorbs Na+ and Cl- from filtrate into interstitial fluid
• Distal tubule – Selectively secretes and absorbs different ions to maintain blood pH and electrolyte balance
• Collecting duct – Reabsorbs solutes and water from the filtrate

Question 22

What are the components of urine?

Answer 22

Water, NaCl, HCO3, K, Glucose, Albumin, Urea, and Creatinine

Question 23

How much water is recovered in the nephron?

Answer 23

 About 66% - 70% of water is recovered from the proximal convoluted tubule and descending Loop of Henle.
* If aldosterone has been secreted the distal tubule and collecting duct will also absorb water.

Question 24

Define active transport. What are some solutes actively transported across the membrane?

Answer 24

 Movement of solutes across a membrane against a gradient using ATP or carrier proteins.
 Na, HCO3, glucose, amino acids, proteins, phosphate, sulfate, Mg, Ca, Uric acid, Cl

Question 25

What is passive transport and what are some solutes that use passive transport?

Answer 25

 Controlled by differences in substance concentration gradients on sides of a membrane.
 H2O, Cl-, K, urea

Question 26

What is glucose renal threshold?

Answer 26

Glucose is secreted in urine if glucose serum concentration is above 160 mg / dL.

Question 27

What are the three systems used to maintain pH at 7.4?

Answer 27

1. Blood buffer system using buffers to prevent pH from fluctuating.
2. Pulmonary system - exhale or retain CO2
3. Renal system - excrete bicarbonate ions or H+ ions or exchanging ions for buffers.

Question 28

What is angiotensin II and what is its function?

Answer 28

*Angiotensin II is the active form of the hormone. It’s produced by the juxtaglomerular cells in the kidneys.

Its functions are:
* Dilates afferent arteriole
* Constricts efferent arteriole
* Stimulate reabsorption of sodium (water follows salt) in. Proximal convoluted tubule
* Triggers aldosterone release

Question 29

How does renin influence blood pressure and water balance?

Answer 29

Renin starts the renin-angiotensin Aldosterone system which will ultimately increase blood pressure by vasoconstricting blood vessels (increase blood pressure). The aldosterone secreted will increase water permeability in the collecting duct and the distal tubule (increasing water volume).

Question 30

What is the function of the antidiuretic hormone?

Answer 30

 Increases water permeability in distal tubule and collecting duct of nephron
 Increases transport of Na+ in Loop of Henle which enhances countercurrent multiplication and urea cycling

Question 31

What stimulates renin production?

Answer 31

• Low blood pressure
  *Potassium increases
  *Low blood volume

Question 32

What inhibits renin production?

Answer 32

• High blood volume
  *High blood pressure
  *Potassium decreases

Question 33

What is the criteria for a substance measure GFR?

Answer 33

 Endogenous preferred
 Completely filterable from plasma
 Not be secreted by. Renal blues
 Not be reabsorbed by renal tubules

Question 34

What is the units used in GFR?

Answer 34

Milliliters per minute

Question 35

What is cystatin?

Answer 35

 Small protein produced by all uncleared cells. It’s filtered by the glomerulus and in a healthy patient it is not found in urine.
 Cystitis is absorbed and catalyzed by renal tumbles and broken down. No Cystitis C is secreted in. Urine.
 Small. Protein is ideal for long term monitoring of renal function.
 Serum levels directly reflect GFR.
 Normal range is 0.51 to 0.98 mg/ L
 Another use it has is it can determine drug dosages and evaluate uremia

Question 36

What is cystatin?

Answer 36

 Small protein produced by all uncleared cells. It’s filtered by the glomerulus and in a healthy patient it is not found in urine.
 Cystitis is absorbed and catalyzed by renal tumbles and broken down. No Cystitis C is secreted in. Urine.
 Small. Protein is ideal for long term monitoring of renal function.
 Serum levels directly reflect GFR.
 Normal range is 0.51 to 0.98 mg/ L
 Another use it has is it can determine drug dosages and evaluate uremia

Question 37

Where does creatinine come from?

Answer 37

Produced as a result of muscle destruction.