Block 10 - Kidney function and failure Flashcards
(130 cards)
1
Q
Define hydronephrosis
1 possible cause
A
Urine builds up in the kidneys
Rapid weight loss causing the kidneys to drop
2
Q
What are the two types of nephrons?
What is their percentage?
A
Corticol nephron (85%) mainly in the cortex Juxtamedullary nephron (15%) mainly in the medulla
3
Q
Explain the myogenic mechanism of blood pressure control
A
The afferent arteriole smooth muscle adapts to systemic blood pressure
To increase blood pressure it constricts to decrease filtration
To decrease blood pressure it dilates to increase filtration
4
Q
Explain how the macula densa cells control blood pressure
A
Macula densa cells in the ascending loop
Increase the GFR = high blood pressure
Increase GFR = more NaCl in tubule
NaCl detected by macula densa cells = release vasoconstrictive agents = less blood to glomerulus = lower GFR and less NaCl in the tubule
Less macula densa mediators if a low blood pressure
5
Q
Draw the RAAS pathway
A
Renin –(angiotensinogen)–> ANG1 –(ACE)–> ANG2 –> Aldosterone
6
Q
Can sodium be secreted?
A
NO - only filtered
7
Q
What is it called when there is glucose in the urine?
A
Glycosuria
8
Q
How are sodium and glucose reabsorbed by the kidney?
A
Glucose and Na co-transported into the nephron cell
Glucose into the blood via a GLUC transporter
Na into the cell via an ATP pump (3 Na in and 2K out)
9
Q
What does progesterone act as?
A
A diuretic
Blocks aldosterone
10
Q
Give 2 hormones which are similar to aldosterone
A
Oestrogen
Corticosteroids
11
Q
What parts of the heart produce naturietic peptides?
A
Atrial NP produced by overstretched cardiomyocytes in the atria
N-Type NP produced by overstretched cardiomyocytes in the ventricles
12
Q
Explain how bicarbonate is reabsorbed and hydrogen ions are secreted in the PCT
Which enzyme is involved
A
In the filtrate H+ + HCO3- –> H2CO3 (impermeable)
H2CO3 –> H20 + CO2 (enter the cell)
In the cell they recombine and separate again
H+ (re-enters tubule in exchange for Na+ using ATP)
HCO3- (enters capillary in exchange for Cl-)
CARBONIC ANHYDRASE
13
Q
Why do you need to take care with using loop diuretics with heart and kidney failure?
A
Can lose sodium and potassium
14
Q
Which transporter is found in the Loop of Henle?
A
Na/K/Cl
15
Q
Which 3 things act on the DCT?
A
Na/Cl transporter
PTH
Thiazide diuretics
16
Q
What are the 2 cells found in the CD?
What are their roles?
A
Principal cells: Water and sodium balance
Intercalated cells: Acid base balance
17
Q
How much potassium is absorbed in the PCT?
What happens when levels in the body increase/decrease?
A
90% reabsorbed regardless of need
Principal cells absorb or excrete it in exchange for sodium
18
Q
What is it called when there is too much water in the urine?
A
Diabetes insipidus
19
Q
Give two methods to assess kidney function
A
Glomerular filtration rate (eGFR)
Renal clearance
20
Q
What is renal clearance?
How is it measured?
A
Volume of plasma cleared of a substance in 1 min
Clearance = (urine conc x urine vol) / plasma conc
21
Q
What is renal clearance standardised against
How can you tell if a substance is all reabsorbed or secreted
A
Standardised against a substance which is not secreted or absorbed (all is filtered) e.g. inulin (or creatinine)
If glucose level is LOWER than the inulin standard then it is all REABSORBED
(higher = secreted)
22
Q
Does the blood pressure increase or decrease if you have renal disease?
A
Increase
23
Q
Where does pain from the kidney radiate to?
A
Groin
24
Q
6 causes of haematuria from the kidneys
A
Polycystic, tumour, scarring, cystitis
Glomerular nephritis, vessels
25
What age group suffers from LUTS?
Elderly
26
What does it mean if the urine is a brown/red colour?
Increased myoglobin
| Breakdown product of muscles
27
What does it mean if the urine is cloudy?
Infection (increased WBC)
28
What does it mean if the urine is gravely?
Stone fragments
29
What does it mean if the urine is airy?
Vesico-colic fistula
30
What does it mean if there are debris in the urine?
Infection, vesico-colic fistula, infarction
31
3 causes of anuria
Severe acute kidney injury
Longstanding end stage renal failure
Post renal obstruction
32
2 causes of oliguria
| 3 examples
Acute kidney injury (reversible)
| Usually drug induced (NSAID, steroid, antibiotic)
33
2 causes of polyuria
Early chronic kidney disease (can't concentrate urine)
| Osmotic diuretic
34
Define Nephrotic and Nephritic syndrome
3 symptoms of nephrotic
2 symptoms of nephritic
Nephrotic: PrOtein in the urine
(increased lipids, decreased albumin, oedema)
Nephritic: Protein and blood in the urine
(inflammation of the glomeruli, oliguria)
35
Define oliguria
Reduced urine output
36
What is angiography used to look at in the kidneys?
Chronic kidney injury
37
5 biochemical markers of renal failure
| Are they increased or decreased?
Increased urea, creatinine and phosphate
| Decreased calcium and albumin
38
What happens to the levels of protein bound drugs in chronic renal disease
Decreased albumin means decreased protein bound drugs
| Side effects may occur
39
What defines chronic kidney failure?
GFR less than 6 ml/min for more than 3 months
40
4 pre-renal causes of AKD
Decreased perfusion
Heart failure
Decreased blood pressure (shock)
Hypovolemia
41
4 renal causes of AKD
Ischaemia
Nephrotoxic drugs
Nephron disorders
Sepsis
42
2 post-renal causes of AKD
Urethral/bladder obstruction (tumour or prostate)
| Kidney/bladder stones
43
6 causes of chronic kidney disease
```
Diabetes
Increased blood pressure
Glomerular disease
Hereditary
Nephritis
Tumours
```
44
What are the 5 stages of chronic kidney disease?
1. Normal GFR (more than 90)
2. Mild decrease (60-89)
3. Moderate decrease (30-59)
4. Severe decrease (15-29)
5. End stage renal disease (less than 15)
45
One major advantage for genetic screening
Know if they will pass it on to any children
46
What is the name of the main genetic kidney disease?
| When are the two types diagnosed?
Autosomal dominant polycystic kidney disease
T1: 30-40 yrs
T2: 70+ yrs
47
How can CKD lead to metastatic calcifications in vessels?
Decreased GFR decreases Vitamin D synthesis so decreases Ca absorption from the GI tract
Decreased Ca increases PTH so increases the amount of Ca released from bones causing vessel calcifications
48
How does heart failure cause kidney disease?
Heart failure --> Decreased CO --> Decreased blood to the kidney --> Renal hypoxia and necrosis
49
What are the 3 systems which regulate blood pH?
Seconds: Chemical buffers
Minutes: Respiratory centres
Days: Renal system
50
What are the 3 main kidney buffering systems?
Bicarbonate
Phosphate
Ammonia
51
What is the main intracellular buffering system?
H+ + Hb HHb
52
Explain the bicarbonate buffer system
H20 + CO2 --> H2CO3 --> H(+) + HCO3(-)
H(+) secreted
HCO3(-) reabsorbed in the PCT
53
Explain the phosphate buffer system
HPO4(2-) + H(+) --> H2PO4(-)
H2PO4(-) excreted in the urine
54
Explain the ammonia buffer system
(Glutamine metabolism)
IN THE PCT:
Glutamine --> NH3 + HCO3(-)
NH3 + H(+) NH4(+)
IN THE CD:
NH4(+) reabsorbed then excreted again into the urine
55
When do you excrete H+?
You use the buffer systems first but after the buffer systems have been 'used up' you then excrete H+
56
What happens if there is a problem with the kidney (in regards to ammonia metabolism)
Ammonia re-enters the blood and is converted to urea in the liver causing toxicity
57
5 causes of metabolic acidosis
Ingestion of acid
Increased lactic acid (exercise, diabetic ketoacidosis)
Increased ketone bodies (diarrhoea, diabetes, alcohol, increased protein)
Aspirin overdose
Starvation
58
5 causes of metabolic alkalosis
```
Antacid
Fruit
Vomiting
Hypokalemia
Steroids
```
59
6 causes of respiratory acidosis
Respiratory depression (narcotic drugs, anaesthetic)
CNS disease, depression, brain trauma
Interference with respiratory muscles (disease, drug, toxin)
Restrictive/obstructive lung disease
60
4 causes of respiratory alkalosis
Hyperventilation
Overventilation on a mechanical ventilator
Altitude
Fever
61
What do the kidneys do if the pH is low?
Intercalated cells secrete H+
| Principal cells make new bicarbonate
62
What do the kidneys do if the pH is high?
Principal cells do not reabsorb filtered bicarbonate
63
5 reasons why infants are at an increased risk of acid-base imbalance?
```
Decreased volume on the lungs
Increased metabolic rate
Increased rate of water loss
Inefficient kidneys
Excessive fluid shift (increased intake and output)
```
64
2 reasons why the elderly are at an increased risk of acid-base imbalance?
Unresponsive to thirst cues
| Slow homeostasis
65
Is the patient compensating if:
1. CO2 and HCO3 are BOTH increased/decreased?
2. One value is increased and the other is normal?
3. One value is increased and the other decreased?
1. Yes - compensating
2. No - not compensating
3. Would never be seen
66
Give 8 examples of organic anions excreted by the kidney
Urea, Ketoacids, Bile salts
Penicillin, Diureitcs, Cephlasporin, Aspirin
Investigative contract
67
Give 4 examples of organic cations excreted by the kidney
Creatinine
| Quinidine, Trimethoprim, Cimetidine
68
How can you increase the therapeutic effect of the drug by using the PCT?
The PCT is competitive so adding specific drugs may decrease re absorption so other drugs stay in the plasma for longer and increase their therapeutic effect
69
2 things that the urine concentration of a drug is dependent on?
Entrance of the drug into the tubule
| Reabsorption of the drug from the tubular fluid
70
What does the drugs ability to remain in the tubule depend upon?
Its charge
| Ionised (charged) drugs stay in the tubule more effectively (e.g. acid drug alkaline urine)
71
What are the three layers of the bladder?
Outer connective tissue
Middle smooth muscle (detrusor)
Inner transitional cell epithelium (elastic)
72
Define urodynamics
Investigation of micturition
73
Define cytometry
Measuring the pressure-volume relationships of the bladder
74
What can failure of the detrusor muscle cause?
| How is it worsened?
Voiding symptoms
| Patients push against resistance = more over-stretched
75
Why might you not notice an enlarged prostate to begin with?
In the early stages increased detrusor pressure maintains flow but eventually this muscle weakens causing voiding symptoms
76
Give 1 cause of a acute urinary retention - who is it most common in?
Give 3 causes of chronic urinary retention
Acute: Surgery (men)
Chronic: Prostate obstruction, urethral structure, LMN lesion affecting the bladder
77
Who does incontinence affect?
Women of all ages
78
Most common incontinence in men?
| Most common cause of incontinence in men?
Overflow
| Neuropathic problems
79
What are the two types of incontience involved in mixed incontinence?
Stress and urge
80
Give 8 risk factors for incontinence
```
Pregnancy
Menopause
Chronic cough
Obesity
Pelvic organ prolapse
Constipation
Lifting weights/strenuous aerobic exercise
```
81
4 treatments for female stress incontinence
Support of the bladder neck
Increasing urethral resistance
Injection of a bulking agent to the urethra (urethral sphincter augmentation)
Urethral and vaginal slings
82
Main cause of an overactive bladder
Idiopathic
83
4 treatments of an overactive bladder
Sacral nerve stimulation
PTNS (percutaneous tibial nerve stimulation)
Urinary diversion
Interstim therapy (implantable neuromodification)
84
Give 3 examples, other than E.coli, of bacteria which can cause UTI
S. aureus
S. epidermidis
P. mirabilis
85
What can cause a UTI after a kidney transplant?
BK and JC virus
86
What is another name for a descending UTI?
| Where are they mainly found?
Haematogenous
| Common in ICU
87
What UTI is a major problem in pregnancy?
What would usually happen if a patient had this type of UTI?
Asymptomatic UTI - screened for during pregnancy
UTI's are otherwise only treated if the patient shows symptoms and has an immune response
88
3 host immune defences to prevent UTI
Secretory IgA: binds to inactivate bacetria
Lactoferrin: binds to Fe to prevent bacteria using it
Mucopolysacchrides: prevent bacetria from binding
89
2 bacterial virulence factors needed for UTI
Type 1 fimbriae: projections to mannose membranes --> colonisation
Type P fimbriae: K antigen (capsule) prevents phagocytosis
90
6 risk factors for UTI
Female, Pregnancy, Anatomical abnormalities (residual urine)
| Catheter, Stones, Surgery
91
Define dysuria
Pain or difficulty urinating
92
5 things that work and 3 things that don't work when trying to prevent catheter associated UTIs
Works: Not catheterising, Decreasing duration, Aseptic insertion, Closed Drainage, Silver bonded catheters
Doesn't work: Antiseptic to urethral meatus, Disinfectants in drainage bag, Antiseptic/antibiotic irrigation of the bladder
93
4 causes of urethral syndrome
Reduced bacterial count
Bacteria don't grow on that culture
Non-infective (other inflammation)
STI
94
How long do you give antibiotic prophylaxis for UTI treatment?
6 months
95
What do you give to help recurrent UTIs in post-menopausal women
HRT
96
What, in the family history, can increase a child's risk of UTI?
Renal abnormalities
97
What is found in the upper and lower urinary tract?
Upper: Kidneys and ureters
Lower: Bladder and urethra (prostate and genitals)
98
What cancers are under the heading 'uro-oncology'
Kidney, bladder, prostate, testicular, penile
99
Define andrology
Problems with the male genitalia
100
What are the 2 types of kidney transplant?
Cadeveric or live donor
101
What indicates infection on histology?
Black dots
102
Give 4 examples of congenital problems with the kidneys
Horse-shoe kidney
More ureters/larger ureters (infection and stones)
Vesicouretic reflux (air from a hole)
Penile chordae (bent)
103
What histological changes are found in BPH?
Stromal-glandular hyperplasia
104
3 treatments for BPH
Anti-androgen drugs
Core-ing
Catheter (in acute situations to release fluid and prevent renal failure)
105
4 causes of epididymitis
STI
E.coli
Mumps
Orchitis
106
3 causes of chemical cystitis
Ketamine, Mitomycin, BCG
107
What are kidney stones called?
Urolithiasis
108
4 causes of urethral stricture
Neoplasm
Infection
Trauma
Compression
109
4 risk factors of kidney stones
Male
Dehydration
Diet
Genetic
110
What type of carcinoma is renal?
1 risk factor
When does it present?
Clear cell
Smoking
Presents late as you have two kidneys
111
2 types of testicular cancer
| 2 risk factors
Seminomas
Non-seminomas (carcinomas of the embryological membranes)
Family history and undescended testes
112
What are the 3 types of bladder cancer?
| 6 risk factors
Transitional cell carcioma
Squamous cell carcinoma
Adenocarcinoma
Chronic irritation, Smoking, Asbestos, Crude oil, Rubber, Plastic
113
What type of cancer is prostate cancer?
3 risk factors
Problem
Adenocarcinoma
Family history, age, ethncity
Overdiagnosed - surgery and hormones have side effects
114
What type of cancer is penile cancer?
| 4 risk factors
Squamous cell carcinoma
| HPV, Smoking, Poor hygiene, Smegma
115
Give 2 congenital causes of protein loss?
NPHS1 gene: Finnish type --> nephrin between podocytes
| NPHS2: Steroid resistant --> podicin in podocytes (children)
116
2 problems that can occur with the glomerulus which can cause proteinuria
Podocyte injury
| Loss of negative charge
117
Causes of nephrotic syndrome:
- Children (2)
- Adults (7)
- Both (2)
Children:
Glomerulonephritis (minimal change/ focal segmental)
```
Adults:
Glomerulonephritis (membranous)
Neuropathy (membranous, IgA, diabetic)
Amylodosis
SLE
Cancer
```
Both:
Minimal change disease
Viral infection
118
Causes of nephritic syndrome:
- Children (3)
- Adults (4)
Children:
Haemolytic uraemic syndrome
Hensoc-schonein purpura
Post-strep glomerulonephritis
```
Adults:
Goodpasture's
ANCA vasculitis
SLE
Primary or secondary mesngio-capilalry glomerulonephritis
```
119
```
Explain the pathophysiology of kidney injury caused by:
SLE
Goodpasture
Infections
Diarrhoea
```
SLE: Antigen-antibody complex deposit in basement membrane
Goodpasture: Abnormal antigen on basement membrane
Infections: Bacterial antigens bind to basement membrane
Diarrhoea: Toxin on the capillary membrane
Complement --> inflammation and cell injury
120
What is vital for a diagnosis of end stage renal failure?
Bilateral insult
121
Define azotemia
| 1 possible cause
Abnormally high compounds containing nitrogen in the blood (e.g. urea, creatinine)
Caused by a reduced GFR
122
How can renal failure cause polyuria?
When water is filtered but nothing else is
123
Example of a pre-renal cause of renal failure (2)
Blood vessel issues
| e.g. clot, hypovolemia
124
Give 3 classes (6 examples) of intra-renal renal failure
Glomerular injury: Diabetes, Glomerulonephritis
Tubular injury: Pyelonephritis scarring, Drugs
Vascular injury: Hypertension, Vasculitis
125
# Define uraemia
12 symptoms
Increased levels of uric acid
Anorexia , Breathlesness, Chest pain, Cognitive impairment, Coma, Fatigue, Itching, Metallic taste, Nausea, Smelly breath, Seizures, Vomiting
126
What does sodium and water retention do to the JVP?
Increases it
127
Explain the underfill model of oedema
| Who is it more common in?
Reduced oncotic pressure = more water into tissues
Reduced plasma volume activates RAAS
Increased hydrostatic pressure = more water out
Children
128
Explain the overfill model of oedema
Kidney damaged = Na + H2O retained but protein lost
| Increased hydrostatic pressure and reduced oncotic pressure
129
2 causes of primary oedema (related to the kidney)
Glomerulonephritis
| Membranous neuropathy
130
4 causes of secondary oedema (related to the kidney)
Diabetic neuropathy
SLE
Cancer
Chronic viral infection
