the kidney and urinary tract: what are they and how can they go wrong?

Question 1

what is the cortex full of?

Answer 1

glomeruli and PCT

Question 2

how many glomeruli in normotesnives?

Answer 2

1-2 million per kidney

Question 3

how many glomeruli per kidney in people with essential hypertension?

Answer 3

0.5-1 million per kidney

Question 4

why do most people with kidney disease have arterial hypertension?

Answer 4

kidney failure — can’t excrete salt and water — retained in body in circulation system — increases BP

Question 5

what is a good way to treat hypertension in kidney failure?

Answer 5

remove excess salt and water — dialysis, diuretics (eg. furosemide)

Question 6

why do you get oedema in kidney disease?

Answer 6

excess salt and water build up and kidney leaks a lot of protein and oncotic pressure falls —> high BP and excess salt and water leak into interstitial space causing oedema

Question 7

what do the kidneys have a vital role in excreting?

Answer 7

K+

Question 8

how does hyperkalaemia present on ECG?

Answer 8

peaked T waves

Question 9

how can hyperkalaemia be treated?

Answer 9

dialysis, or injection of insulin intravenously with glucose

Question 10

what does the urinary bladder do?

Answer 10

low pressure reservoir which intermittently and completely expels urine per urethra

Question 11

what is the bladder made of?

Answer 11

smooth muscle bundles under autonomic nervous control

Question 12

Answer 12

Question 13

what is the urothelium surface covered in?

Answer 13

hexagonal plats made of uroplakin

Question 14

what is the function of uroplakin?

Answer 14

makes the urothelium water tight and prevents water and all the excretory products (like urea) from diffusing back into the body

Question 15

what do parasympathetic nerves release?

Answer 15

ACh

Question 16

what nerves make the bladder contract, detrusor muscle contract and make rhe bladder void?

Answer 16

parasympathetic nerves

Question 17

what effect does the adrenergic system have on the bladder?

Answer 17

makes it relax

Question 18

what happens when the wave of smooth muscle contraction from the top to the bottom of the ureter doesnt work?

Answer 18

build up of urine at the top of ureter — hydronephrosis

Question 19

what are the key clinical symptoms and signs of disease of the lower renal tract?

Answer 19

• dysuria
• frequency of micturition
• incontinence of urine
• poor urinary stream
• haematuria
• pain (caused by acute bladder outflow obstruction, renal colic, urosepsis etc)

Question 20

what dont you get a lot of in LOWER urinary tract disease?

Answer 20

proteinuria

Question 21

proteinuria + haematuria = ?

Answer 21

glomerular kidney disease

Question 22

primary disease of the lower tract can cause what?

Answer 22

secondary kidney failure mediated by impairment of urine flow

Question 23

what are they 2 ways of classifying kidney and urinary tract diseases?

Answer 23

CONGENITAL malformations

ACQUIRED — tumorus and non-tumours

genetic and environmental causes

Question 24

what are the 3 main histological varieties of kidney malformations?

Answer 24

1. hypoplasia (too few nephrons)
2. dysplasia (undifferentiated kidney sometimes with cysts)
3. agenesis (absent kidney)

Question 25

what are the most common mutations in malformed kidneys?

Answer 25

HNF1B mutations

Question 26

Answer 26

Question 27

what is prune belly syndrome?

Answer 27

- aka. Eagle-barrett syndrome - rare genetic birth defect - about 97% if those affected are male - triad of symptoms : partial or complete absence of the stomach (abdominal) muscles, failure of both testes to descend into the scrotum (bilateral cryptorchidism), and/or urinary tract malformations. babies have massively large bladders

Question 28

descirbe one of the mutations in prune belly syndrome

Answer 28

mutation in myocardin = necessary for formation of smooth muscle —> mutated means smooth muscle in bladder not working properly so can’t empty bladder

Question 29

what are ‘pre-renal’ causes of acquired kidney failure?

Answer 29

cant make urine - shock eg. massive blood loss, septicaemia - cardiac and liver failure — poor kidney perfusion

Question 30

what is instinsic kidney disease?

Answer 30

= disease of the kidney itself - glomerular disease (eg. Alpert syndrome, diabetes mellitus and immune-mediated glomerulonephritis) - tubular disease (eg. pyelonephritis, autosomal dominant polycystic disease, nephrotoxins)

Question 31

what are ‘post-renal’ causes of acquired kidney disease?

Answer 31

- urinary flow impairment eg. stones tumours and dysfunctional bladders); need to block BOTH kidneys

Question 32

what is anti-glomerular basement membrane nephritis?

Answer 32

acquired antibodies that attack glomerular basement membrane

Question 33

what is glomerular filtration rate in early diabetes mellitus?

Answer 33

actually INCREASED

Question 34

what happens to glomerular disease in diabetes mellitus without treatment?

Answer 34

there is a progressive decline in renal function with sclerosis of glomeruli

Question 35

tubular vs glomerular epithelia?

Answer 35

tubular epithelia have the capacity to regenerate, glomerular dont

Question 36

what does infectious pyelonephritis cause?

Answer 36

tubular disease

Question 37

describe autosomal dominant polycystic kidney disease (ADPKD)

Answer 37

- ADPKD affects 1/1000 people - UK Renal Registry: Polycystic kidney disease is the cause of 9% end-stage renal failure in adults - kidney tubules initially form normally, but as young et older they dilate and squash the useful nephrons in between them —> kidney failure around 40 years old

Question 38

how is PKD treated?

Answer 38

tolvaptan = vasopressin receptor antagonist — slows down the progression of cyst growth

Question 39

what kind of kidney stones don’t show up on plain x rays?

Answer 39

uric acid stones

Question 40

what is the Wilms tumour?

Answer 40

kidney cancer in children

Question 41

what is the name of the common kidney tumour in adults?

Answer 41

clear cell carcinoma — arises in the proximal tubule

Question 42

what is the commonest bladder cacner?

Answer 42

transitional cell carcinoma

Question 43

where does prostate cancer like to metastasise to? describe

Answer 43

- bone - unlike many other cancers, the bone metastases of prostate cancer are sclerotic - dense areas (vs lytic - make holes in bone)

Question 44

what feeling of prostate is suggestive of cancer in DRE?

Answer 44

bumpy and hard

Question 45

kidney failure does not cause one of these signs/symptoms? A - difficulty breathing B - high BP C - jaundice D - leg swelling E - sudden death from hyperkalaemia

Answer 45

jaundice

Question 46

which of these suggests a glomerular cause of kidney disease? A - bacteria grown from the urine B - enlarged prostate on palpation C - family history of kidney disease D - RBCs and protein in urine E - renal colic

Answer 46

D - rbcs and protein in urine