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MLT 203, Fall 2023 > Renal Function > Flashcards

Renal Function Flashcards

1
Q

How many mL/min of blood flows through the capillaries in the glomerulus to be filtered?

A

1200-1500

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2
Q

Primary functions of the Kidneys (3)

A
  1. Filtration
  2. Secretion
  3. Reabsorption
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3
Q

Functions of the Kidneys (8)

A
  1. Controls Fluid Balance
  2. Regulates electrolytes (sodium, potassium, calcium, magnesium)
  3. Prevents acid build up
  4. Eliminates waste products
  5. Produces urine
  6. Regulates blood pressure
  7. Produces Calcitriol (increases intestinal reabsorption of calcium)
  8. Manufactures erythropoietin (a hormone that stimulates RBC production)
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4
Q

Kidney Anatomy (10)

A
  1. Renal Artery
  2. Renal Vein
  3. Renal Pelvis
  4. Capsule
  5. Cortex
  6. Medulla
  7. Minor Calyx
  8. Major Calyx
  9. Ureter
  10. Nephron
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5
Q

Renal Artery

A

Carries blood from the aorta to the kidney

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6
Q

Renal Vein

A

carries filtered blood from the kidney to the inferior vena cava

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7
Q

Renal Pelvis

A

funnel shaped duct that collects urine from the calyces

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8
Q

Capsule

A

protective outer layer

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9
Q

Cortex

A

inner layer, contains nephrons

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10
Q

Medulla

A

Middle layer, contains renal pyramids

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11
Q

Minor Calyx

A

collects the urine from renal pyramid and drains into a major calyx

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12
Q

Major Calyx

A

branches off renal pelvis that collect urine

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13
Q

Ureter

A

carriers urine to the bladder

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14
Q

Nephron

A

functional unit of the kidney

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15
Q

Functions of the Nephron (3)

A
  1. Filters blood and produces urine in the process of removing waste and excess substances from the blood
  2. Concentrates the urine
  3. Maintains pH and electrolyte balance
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16
Q

How many nephrons are there per kidney?

A

1-1.5 million

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17
Q

What are the two types of nephrons

A
  1. Cortical Nephrons (85%)
  2. Juxtamedullary (15%)
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18
Q

Cortical Nephrons

A

*Located primarily in the cortex
*Responsible for the removal of waste and reabsorption of nutrients

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19
Q

Juxtamedullary Nephrons

A

*Have very long loops of Henle that extend deep into the medulla
*Responsible for concentrating the urine

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20
Q

Nephron Anatomy (10)

A
  1. Glomerulus
  2. Bowman’s Capsule
  3. Juxtaglomerular apparatus
  4. Afferent arteriole
  5. Efferent arteriole
  6. Peritubular capillaries
  7. Proximal Convoluted Tubule
  8. Distal Convoluted Tubule
  9. Loop of Henle
  10. Collecting Duct
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21
Q

Glomerulus

A

a tiny ball-shaped structure composed of 8 capillary blood vessels (lobes)

major site of blood filtration

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22
Q

Bowman’s Capsule

A

structure surrounding the glomerulus

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23
Q

Juxtaglomerular apparatus

A

specialized structure responsible for regulating blood pressure and the filtration rate of the glomerulus

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24
Q

Afferent Arteriole

A

supplies blood to the glomerulus

(smaller arteriole)

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25
Q

Efferent Arteriole

A

Takes blood away from the glomerulus

(larger arteriole)

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26
Q

Peritubular Capillaries

A

surround the PCT and DCT

Responsible for reabsorbing essential nutrients from the filtrate

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27
Q

PCT

A

duct that lies between Bowman’s capsule and the loop of henle

Allows for the reabsorption of glucose, sodium, chloride, and water from the glomerular filtrate

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28
Q

DCT

A

duct that lies between the loop of Henle and the collecting ducts

Responsible for the final adjustments to urine composition

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29
Q

Loop of Henle

A

U-shaped duct between the proximal and distal convoluted tubules

Functions in water reabsorption

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30
Q

Collecting ducts

A

long duct that receives urine from several nephrons and discharges it into the pelvis of the kidney

Responsible for the final concentration of urine through the reabsorption of water

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31
Q

What is total renal blood flow?

A

The volume of blood (plasma and cells) delivered to the kidneys per unit of time

approx. 1200 mL/min

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32
Q

What is total renal plasma flow?

A

The volume of plasma delivered to the kidneys per unit of time

approx. 600-700 mL/min

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33
Q

What 3 cellular layers does filtrate pass through?

A
  1. Capillary wall membrane - contains small pores that increase permeability
  2. Basement membrane
  3. Visceral Epithelium of Bowman’s Capsule - a network of podocytes restricts the passage of large molecules
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34
Q

Filtration occurs due to the presence of ________ ________ created by the smaller size of the _______ arteriole and the increased permeability of the _________ ________

A

hydrostatic pressure

efferent

glomerular capillaries

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35
Q

How can the nephron control the blood pressure at the glomerulus?

A

By constricting or relaxing the afferent and efferent arterioles

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36
Q

When blood pressure is high, what arteriole constricts to restrict blood flow to the glomerulus?

A

Afferent arteriole

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37
Q

When blood pressure is low the ______ arteriole is dilated and the ______ arteriole is constricted to allow increased blood flow in the glomerulus.

A

Afferent

Efferent

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38
Q

Pore size of capillaries

A

66 Dalton

*any molecules smaller than that will be readily filtered, anything larger will not fit through the pores.

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39
Q

How can chronic high blood pressure, like with diabetes, cause damage to the capillary pores?

A

By forcing molecules that are too large out of the pores

Ex. Do Microalbumin test to asses damage

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40
Q

The rates of _____ ______ and ______ ______ can give an indication of how well the kidney is functioning.

A

Renal blood

Renal Plasma flow

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41
Q

Renal plasma flow is estimated using…..

A

The effective renal plasma flow -PAH clearance

Flick’s Principle
Flow in = Flow out
what flows in should flow out.

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42
Q

How can renal blood flow be calculated?

A

From the ERPF

Blood = plasma + hematocrit

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43
Q

What is arteriole dilation or constriction?

A

an auto-regulatory mechanism controlled by the juxtaglomerular apparatus and macula densa

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44
Q

Drops in Blood pressure cause the _____ arterioles to dilate and the ______ arterioles to constrict to maintain pressure and prevent a decrease in the amount of blood being filtered

A

Afferent

Efferent

  • This also prevents increased levels of toxic products in the blood
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45
Q

Increased blood pressure causes the ______ arteriole to constrict and the ________ arteriole to dilate to maintain pressure and prevent over filtration

A

Afferent

Efferent

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46
Q

Renin-Angiotensin-Aldosterone System (RAAS)

A

The juxtaglomerular apparatus and macula densa monitor changes in BP and plasma sodium content.

Low sodium and decreased BP causes the juxtaglomerular apparatus to secrete renin which initiates a cascade reaction (RAAS)

Angiotensin II causes dilation of the affferent arterioles and constriction of the efferent arterioles, increased

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47
Q

Angiotensin II causes

A
  1. dilation of the afferent arterioles and constriction of the efferent arterioles
  2. increased sodium reabsorption in the PCT leads to the release of aldosterone and AVP
  3. Aldosterone increases sodium reabsorption form the DCT
    4.AVP increases water reabsorption from the collecting duct and tubules

LEADING TO AN INCREASE IN BP AND SODIUM CONTENT

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48
Q

Testing for Glomerular Filtration

A

Clearance tests

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49
Q

Clearance tests do what?

A

Measure the rate at which the kidneys are able to clear (remove) a filterable substance from the blood

Must use a substance that is not reabsorbed or secreted by the tubules to ensure filtration is measured correctly

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50
Q

What was one of the first analytes used for clearance testing

A

Urea - because of its presence in all urine and the existence of routine analytical methods, however it was known that about 40% was reabsorbed, so values had to be adjusted for each test

**Urea is not currently used for clearance testing.

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51
Q

What are the best analytes for clearance testing?

A

The ones that are endogenous and are produced at a constant rate

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52
Q

Inulin Clearance

A

*Polymer of fructose, very stable, not secreted or reabsorbed by the tubules, ONLY FILTERED
*One of the original analytes used for testing
*Disadvantage = it is exogenous and must be infused at a constant rate for the duration of the test
*Not currently used for glomerular filtration testing

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53
Q

Beta2 Microglobulin Clearance

A

Really good choice*
*small protein produced by WBCs
*Good analyte because it is endogenous and is produced at a relatively constant rate, as long as there is no inflammation or infection
*ONLY FILTERED not secreted
*99.9% reabsorbed by the PCT
*Disadvantage is that an active immune or inflammatory response increases the concentration and invalidates the test.

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54
Q

Creatinine Clearance

A

*Currently used test
*Abnormal results should be analyzed by follow up testing
*Excellent screening test for GFR in the clinical lab

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55
Q

What is creatinine?

A

A waste product from muscle metabolism and is found at a relatively constant level in the blood

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56
Q

Disadvantages of Creatinine Clearance (5)

A
  1. Small amount is secreted by the tubules
  2. Bacteria can breakdown creatinine if urine is left at RT for an extended time
  3. Some medications can inhibit secretion causing falsely low serum levels
  4. a high meat diet during collection can influence results
  5. Not reliable for patients with muscle wasting diseases
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57
Q

What is cystatin C

A

A small protein produced at a constant rate by all nucleated cells

*Completely filtered by glomerulus and reabsorbed in the tubules

none is secreted

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58
Q

Cystatin C clearance testing

A

*Serum concentrations are unaffected by diet, age, race, gender, or muscle mass
*The serum concentration can be directly related to GFR, and can be measured by immunassay
*Monitoring is recommended for pediatric patients, diabetics, the elderly, and critically ill patients

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59
Q

What is tubular Secretion?

A

The passage of substance from the peritubular capillaries to the filtrate

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60
Q

What is tubular secretion important for?

A

For waste that is not filtered by the glomerulus (ex. protein bound drugs) and for acid base balance (maintain pH)

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61
Q

Protein bound waste in the plasma develops a stronger affinity for….

A

The tubular cells and dissociates from the protein allowing it to be transported into the filtrate

*Used to get rid of many of the products of cell metabolism

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62
Q

Acid-Base balance

A

the body requires a pH of 7.4, so excess acid waste must be eliminated and bicarbonate (base) reabsorbed to maintain balance

if the pH is too basic (too much HCO) bicarbonate will be excreted and H+ will be reabsorbed

If the pH is too acidic, H+ will be excreted and HCO- will be reabsorbed

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63
Q

Where does acid-base balance occur?

A

The acid-base balance exchange occurs in the proximal convoluted tubules

64
Q

What is Tubular Reabsorption?

A

When substances (nutrients) are removed from the glomerular filtrate and returned to the blood

65
Q

Where does tubular reabsorption occur?

A

In the tubules by active and passive transport from the filtrate to the peritubular capillaries.

66
Q

Active transport

A

Requires that the substance to be reabsorbed, be combined with a carrier protein found in the membrane of the renal tubular cells

Electrochemical energy formed from the interaction of the substance and protein transfers the substance across the membrane

67
Q

Passive Transport

A

movement of substance across a membrane as a result of differences in concentration or electrical potential on either side of the membrane

68
Q

Active Transport
PCT =
Ascending Loop of Henle =
DCT =

A

PCT =glucose, amino acids, and salts

Ascending LoH = Chloride

DCT = Sodium

69
Q

Passive Transport
Water =
Urea =
Sodium =

A

Water = PCT, Descending loop of Henle, Collecting duct

Urea = PCT, ascending loop of Henle

Sodium = Ascending Loop of Henle

70
Q

What are tubular reabsorption tests?

A

Tests to determine how well the nephron is concentrating the urine.

71
Q

Tubular reabsorption tests can be indicators for what?

A

Early renal damage because the loss of tubular reabsorption capability is often the first function affected

72
Q

What is specific gravity?

A

For urine is a measure of the density of the dissolved chemicals in the specimen

*can test using the UA dipstick - color change from a chemical reaction determines the SG

73
Q

In a refractometer, the more concentrated the urine, the…

A

the more it causes the light to refract

*The number is read where the light and dark areas meet.

74
Q

Osmolality and Osmolarity are estimations of what?

A

Estimation of the osmolar concertation of plasma or urine

75
Q

Osmolality is proportional to what?

A

The number of particles per kilogram of solvent

76
Q

Measured values of Osmolality

A

Freezing point depression osmometer - common

Vapor pressure depression osmometer

77
Q

Osmolality

A

the amount of solvent will remain constant regardless of changes in temperature and pressure

osmolality is easier to evaluate and is more commonly used

78
Q

Osmolarity is proportional to what?

A

The number of particles per liter of solution.

79
Q

Osmolarity is a _____ value

A

Calculated

*The volume of a solution changes with the amount of solute added as well as with changes in temperature and pressure

It is difficult or determine and not frequently used

80
Q

Osmolarity is unreliable with what conditions? (3)

A

Hyperlipidemia
Hyperproteinemia
Or in presence of osmotically active substances (alcohol or mannitol)

81
Q

The three steps in freezing point depression.

A
  1. The sample is super-cooled to a predetermined temperature, lower than the expected freezing point (specimen remains a liquid below its freezing point)
  2. Then freezing is initiated by a physical shock producing an instant freeze that remains at the freezing point plateau and can be measured with a thermometer (gives one reading for the freezing point)
  3. If the sample is slow cooled it will freeze from the outside to the inside and you will have two different readings for the freezing point.
82
Q

The four steps in vapor pressure depression

A
  1. Sample is absorbed onto a small filter paper disk and placed into a sealed chamber with a temperature sensitive thermocoupler
  2. The sample evaporates and forms a vapor in the chamber, then the temperature of the chamber is lowered and the vapor condenses in the chamber and onto the thermocoupler
  3. The heat of condensation raises the temperature of the thermocoupler to the dew point which is proportional to the vapor pressure from the evaporating sample
  4. The temperatures are compared to standards and converted into milliosmoles
83
Q

Osmolality and Osmolarity Reference Ranges

Serum:
24Hr Urine:
Random Urine:

A

Serum: 275-295 mOsm/kg

24Hr Urine: 300-900 mOsm/kg

Random Urine: 50-1200 mOsm/kg

84
Q

Clinical Significance of Renal tubular tests (4)

A
  1. Used to evaluate renal concentrating ability
  2. Monitor fluid/electrolyte therapy
  3. Monitor renal disease
  4. Diagnose hyper or hypo atremia (high and low sodium levels)
85
Q

Other names for antidiuretic Hormone (3)

A
  1. ADH
  2. Vasopressin
  3. Arginine Vasopressin (AVP)
86
Q

What is antidiuretic hormone?

A

peptide hormone secreted by the posterior pituitary gland

87
Q

ADH is released in response to (2)

A
  1. increased blood osmolality
  2. Decreased blood volume of >5-10%
88
Q

ADH stimulates what?

A

water reabsorption in the tubules

*Causes the walls of the distal tubules to become permeable to water (normally impermeable), causing decreased plasma osmolality and more concentrated urine

*increases water reabsorption from the collecting ducts

89
Q

Aldosterone is a hormone produced by the

A

adrenal cortex

90
Q

Aldosterone is controlled by what system?

A

renin-angiotensin system (RAAS)

91
Q

Aldosterone is released in response to what?

A

Decreased blood flow/pressure in the afferent arteriole and decreased plasma sodium levels

92
Q

Aldosterone stimulates

A

sodium reabsorption in the distal tubules and secretion of potassium and hydrogen ions in the collecting duct.

93
Q

Steps with aldosterone and RAAS

A
  1. In response to decreased blood volume (decreased BP, decreased water) renin is secreted by the renal glomeruli
  2. Renin with angiotensinogen converts angiotensin (from the liver) to angiotensin I
  3. Angiotensin I is converted by ACE from the lungs to angiotensin II
94
Q

Angiotensin II causes

A
  1. vasoconstriction (rapid increase in BP)
  2. Stimulates the adrenal cortex to secrete aldosterone which increases tubular reabsorption of sodium and water and excretion of potassium
  3. stimulates the pituitary to release ADH which increases thirst and reabsorption of water from the tubules and collecting duct
95
Q

NPN compounds are formed from the degradation of (3)

A
  1. proteins
  2. Amino Acids
  3. Nucleic Acids
96
Q

NPN Degradation
Urea =
Creatinine =
Uric Acid =
Ammonia =

A

Urea = results from protein metabolism

Creatinine = waste product from muscle metabolism

Uric Acid = results from purine metabolism

Ammonia = results from protein metabolism, toxic converted to urea

97
Q

NPN are waste products that are filtered by the _____ and excreted in the ______

A

glomerulus

urine

***small amounts are absorbed in the tubules

98
Q

The kidneys help maintain water balance in the body by…

A

changing the amount of water excreted or conserved

99
Q

Water balance is regulated by what?

A

ADH

*released in response to changes in osmolality and blood volume
*increases the permeability of the DCT and collecting ducts to water which increases water reabsorption
*also increases thirst

100
Q

Dehydration (2)

A
  1. tubules and collecting duct reabsorb more water
  2. Creates very concentrated urine (high osmolality)
101
Q

Water excess (2)

A

1.Tubules and collecting duct reabsorb very little water
2. Creates very dilute urine (low osmolality)

102
Q

The kidneys help to maintain electrolyte balance in the body through the excretion and reabsorption of _____

A

Ions
(Na+, Cl-, K+, phosphate, magnesium, calcium)

103
Q

Sodium (Na+) (2)

A

1.Primary extracellular cation in the body
2. Balance is controlled only by excretion, primarily through the kidneys (RAAS)

103
Q

Chloride (Cl-) (3)

A

1.Primary extracellular anion in the body
2. Helps maintain extracellular fluid balance
3. Excretion and reabsorption are controlled by the same mechanisms as sodium (chloride follows sodium)

103
Q

Potassium (K+) (3)

A

1.Primary intracellular cation in the body
2.Regulation of potassium concentrations is very important for cellular metabolism
3. Filtered by the glomerulus and reabsorbed everywhere except the descending loop of Henle.

104
Q

Concentration of potassium is primarily controlled by what?

A

The kidneys

*** has a very narrow normal range, extremes can lead to rapid demise (3.0-5.0 mEq/L)

105
Q

In the PCT potassium can compete with hydrogen ions in their exchange with sodium. This helps counteract what?

A

Metabolic acidosis or alkalosis

106
Q

Metabolic Acidosis

A

H+ concentration is too high!

need to excrete H+ and reabsorb K+ to maintain charge balance (raise pH)

107
Q

Metabolic Alkalosis

A

H+ concentrations are too low!

need to reabsorb H+ and excrete K+ to maintain charge balance (lower pH)

108
Q

Phosphate (2)

A
  1. Higher concentrations are found in the cells than in the extracellular fluid
  2. Regulated by the parathyroid glands, directs the reabsorption of phosphate in the PCT
109
Q

Magnesium (2)

A
  1. Major intracellular cation and important enzyme cofactor
    2.Can exist in both a protein-bound and ionized form
110
Q

The ionized form of Magnesium and calcium is filtered by the ________ and reabsorbed in the _____ under the control of ______

A

Glomerulus

Tubules

PTH

111
Q

Calcium (3)

A
  1. Second most abundant intracellular cation
  2. Important for intracellular messaging
  3. Can exist as protein bound or non-protein bound (if non protein bound can be either in the active, ionized, form or bound on another small ion, ex = phosphate)
112
Q

Major control of calcium is done by _____ and ______

A

PTH - increases calcium levels by increasing the absorption from the gut and bone stores

Calcitonin - decreases calcium levels by decreasing absorption and inhibiting osteoclast activity in the bones

113
Q

The kidneys help maintain pH in the body by conserving ________ ________ and excreting ________ __________

A

bicarbonate ions

metabolic acids

114
Q

Excretion of metabolic acids (2)

A
  1. Hydrogen and other acidic ions that are generated from various metabolic processes are removed from circulation in the kidneys by reacting with buffered bases (neutralization reactions)
  2. The acid waste is then excreted into the urine
115
Q

Regeneration of Bicarbonate Ions (5)

A

1.Bicarbonate ions are filtered by the glomerulus and combine with hydrogen ions in the tubules to form carbonic acid
2. Carbonic acid breaks down into CO2 and water
3. CO2 diffuses into the PCT cells and is converted back into carbonic acid by carbonic amylase
4. In the tubular cells the newly formed carbonic acid is degraded back into H+ and bicarbonate ions
5. The regenerated bicarbonate is reabsorbed into the blood to maintain pH and H+ are secreted back into the tubules to be excreted.

116
Q

Ammonia (NH3)

A

Not filtered by the glomerulus, but is formed in the tubules by the deamination of glutamine

117
Q

Major way the kidneys compensate for metabolic acidosis

A

NH3 reacts with hydrogen ions to form ammonium ions (NH4+) which diffuse out of the tubular lumen and are excreted in the urine

118
Q

Hydrogen Phosphate (HPO4 2-)

A

Filtered phosphate ions can combine with sodium in the tubules to form disodium hydrogen phosphate (NA2HPO4)

It then reacts with hydrogen ions and that product is excreted in the urine

The sodium combines with bicarbonate to form sodium bicarbonate which is reabsorbed

This process can continue eliminating metabolic acid waste, until urinary pH reaches 4.4, after this the renal system cant compensate for decreasing blood pH and metabolic acidosis will occur.

119
Q

Renin (3)

A
  1. Produced by the juxtaglomerular cells of the renal medulla
  2. Secreted in response to low blood volume or pressure
  3. Begins the reactions of the RAAS system
120
Q

Prostaglandins (3)

A
  1. Group of cyclic fatty acids (ex. arachidonic acid)
  2. Formed in most tissues
    -kidney prostaglandins increase renal blood flow, Na+ and water excretion and the release of renin
  3. They also act to inhibit vasoconstriction caused by angiotensin and norepinephrine
121
Q

Erythropoietin

A

Polypeptide made by the kidney that acts on the erythroid progenitor cells in the bone marrow to stimulate RBC production

*regulated by oxygen levels (released in states of hypoxia)

122
Q

Vitamin D is involved in the regulation of (2)

A
  1. Calcium and phosphate balance
  2. bone calcification in the body (increases absorption of Ca2+ in intestines and kidneys)
123
Q

What is responsible for the formation of the active form of vitamin D? (1,25-dihydroxy vitamin D3)

A

The kidneys

124
Q

Vitamin D is controlled by the _______ _______ in response to low _______ levels.

A

Parathyroid gland

calcium

*parathyroid detects low calcium and releases PTH. PTH works to stimulate the osteoclasts and the kidney

125
Q

Vitamin D activation steps (3)

A

1.UV light (sun) converts 7-dehydrocholesterol to vitamin D3 in the skin
2. Vitamin D3 travels to the liver where a hydroxyl group is added forming 25-hydroxy vitamin D3 (inactive form, waits in cardiovascular system until needed)
3. After stimulation by PTH the kidneys add a second hydroxyl group forming 1,25-dihydroxy vitamin D3

126
Q

Analytical Procedures for filtration (2)

A
  1. eGFR - serum creatinine only
  2. Clearance testing - creatinine (serum and urine)
127
Q

Analytical Procedures for Concertation (2)

A
  1. Osmolality (serum or urine)
  2. Specific gravity
128
Q

Analytical Procedures for Urinalysis (4)

A
  1. Chemical Tests (dipstick), macroscopic, microscopic
  2. Creatinine levels
  3. Protein levels
  4. Electrolytes
129
Q

What protein is a UA most sensitive for?

A

albumin

130
Q

Albumin

A

should not be allowed to pass into the urine

indicates glomerular damage

131
Q

B2-Microglobulin

A

Smaller than albumin
Found on most nucleated cells
filtered and should be reabsorbed
***if it is seen in the urine it indicates tubular damage

132
Q

Gamma globulins

A

indicates an infection or immune response

133
Q

Myoglobin

A

Oxygen transport protein in cardiac and skeletal muscle

plasma levels are significantly elevated with severe muscle damage

134
Q

What can cause rhabdomyolysis?

A

High toxic levels of myoglobin

135
Q

Microalbumin

A

Can detect very low levels of albumin

used to monitor patients with diabetes mellitus (increased for renal disease)

136
Q

What is Neutrophil Gelatinase-Associated Lipocalin (NGAL)

A

Protein expressed on neutrophils and epithelial cells, including the cells of the PCT

137
Q

When do NGAL levels increase?

A

Nephrotoxicity
Renal Ischemia
Tubule Injury

*Is a useful early indicator of acute kidney Injury and can assist if determining a patient’s prognosis

138
Q

NGAL urinary levels may also elevate with _______ in the absence of kidney injury

A

Stress

139
Q

What is NephroCheck?

A

Quantitates the levels of tissue inhibitor of metalloproteniase 2 (TIMP-2) and insulin-like growth factor binding protein 7 (IGFBP-7) in the urine

140
Q

What does elevation of TIMP-2 and IGFBP-7 indicate?

A

Indicates the kidneys attempts to protect itself from harmful insults and indicated and increased risk for imminent AKI

141
Q

What is acute Glomerulonephritis?

A

sudden development of inflammation in the glomeruli.

*Often due to recent infection with group A beta-hemolytic streptococci

142
Q

Signs and symptoms of acute glomerulonephritis (7)

A

*rapid onset of proteinuria
*hematuria
*decreased eGFR
*anemia
*elevated BUN and creatinine
*water and sodium retention
*numerous hyaline/granular casts with UA

143
Q

What is chronic glomerulonephritis?

A

may develop silently over several years and often leads to complete kidney failure

*will see gradual development of proteinuria and hematuria as first signs

144
Q

What is nephrotic syndrome?

A

Group of conditions that cause damage and increased permeability to the glomerular basement membrane

145
Q

Signs and symptoms of nephrotic syndrome (3)

A

*MASSIVE proteinuria with hypoalbuminemia (in serum)
*edema
*oval fat bodies in the urine due to hyper lipidemia and lipiduria

146
Q

Tubular disorders result from what?

A

Results in decreased reabsorption and excretion of certain substances and decreased concentration of the urine

147
Q

What is Renal Tubular Acidosis? (RTA)

A

Occurs due to an accumulation of acid in the body due to a failure of the kidneys to appropriately acidify the urine

*MOST CLINICALLY SIGNIFICANT

148
Q

RTA
Distal -
Proximal -

A

Distal - can’t maintain pH gradient between blood and tubular fluid
Proximal - decreased reabsorption of bicarbonate

149
Q

Inflammation of the tubules can also be caused by? (4)

A

*infections
*radiation
*transplant rejection
*medication reactions

150
Q

3 categories of renal failure

A
  1. prerenal
  2. Renal
  3. Postrenal
151
Q

Prerenal

A

Before the kidney
The defect lies in the blood supply before it reaches the kidney (cardiovascular problem)

152
Q

Renal

A

(intrinsic)
Defect in the kidneys
can be due to acute tubular necrosis, vascular obstruction, inflammation or glomerulonephritis

153
Q

Postrenal

A

After the kidney
defect lies in the urinary tract, usually due to an obstruction or rupture of the bladder

154
Q

High risk groups of chronic renal failure

A

Diabetes
hypertension
family history or renal failure
african americans
hispanics
pacific islanders
american indians
seniors

155
Q

Treatment for renal failure

A

Dialysis - simulates renal function with a machine that removes waste from the blood

transplant - one donated kidney is used to replace the work previously done by the diseased kidneys

MLT 203, Fall 2023 (2 decks)

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