Renal Flashcards
(264 cards)
1
Q
What is osmolarity?
A
An estimation of the osmolar conc. of plasma
Is proportional to the number of particles / litre of solution (mmol/l)
2
Q
What is osmolality?
A
An estimation of the osmolar conc. of plasma
Is proportional to the number of particles / kg of solvent (mOsmol/kg)
3
Q
What is tonicity?
A
Related to its affect on the volume of a cell
4
Q
What happens to a RBC placed in a hypertonic solution?
A
Cell shrinkage
5
Q
What happens to a RBC placed in a isotonic solution?
A
Nothing
6
Q
What happens to a RBC placed in a hypotonic solution?
A
Cell lysis
7
Q
Whats are RBCs very permeable to?
A
urea
8
Q
What percentage of the weight of a male is water?
A
~60%
9
Q
What percentage of the weight of a female is water?
A
~50%
10
Q
How much of the total body water is Intracellular fluid?
A
67%
11
Q
What is included in the ECF?
A
Plasma
Interstitial fluid (80%)
Lymph and transcellular fluid (negligible)
12
Q
How can a the volume of a large body of water be calculated?
A
V(l) = D/C
Where V = unknown volume of water
D = dose of tracer added to water
C = concentration of dose present in a small volume of this water
13
Q
What tracer can be used to obtain the total body water volume
A
3H20
14
Q
What tracer can be used to obtain the amount of water in the ECF?
A
Inulin
15
Q
What tracer can be used to obtain the plasma volume?
A
Labelled albumin
16
Q
Is sodium more abundant in the ECF or ICF?
A
ECF
17
Q
Is potassium more abundant in the ECF or ICF?
A
ICF
18
Q
Is chloride more abundant in the ECF or ICF?
A
ECF
19
Q
Is bicarbonate more abundant in the ECF or ICF?
A
ECF
20
Q
What is the primary anion of the ECF?
A
Cl-
21
Q
What are the main ions in the ICF?
A
Potassium, magnesium, negatively charged proteins
22
Q
What organ alters the composition and volume of the ECF?
A
Kidney
23
Q
What 2 types of nephron are found in the kidney?
A
Juxtamedullary (20%) - longer loops of Henle
Cortical (80%)
24
Q
From deep to superficial, what are the histological layers of the glomerular capillaries?
A
Inner endothelial cells
Basement membrane
Podocytes face out into Bowman’s capsule
25
What is the juxtaglomerular apparatus?
The portion of the distal tubule which loops back very near to the glomerulus
26
What histologically connects the distal tubule and the glomerulus at the juxtaglomerular apparatus?
A thick macula densa of the distal tubule and granular cells in some of the arterioles
27
What percentage of blood that enters the glomerulus at any one time is actually filtered?
20%
28
How can the rate of filtration of substance X be calculated?
{X}plasma x GFR
29
How can the rate of excretion of substance X be calculated?
{X}urine x Vu (urine flow rate)
30
How can the rate of reabsorption of substance X be calculated?
rate of filtration - rate of excretion
31
How can the rate of secretion of substance X be calculated?
rate of excretion - rate of filtration
32
What barriers exist for blood filtration in the glomerulus?
```
Glomerular capillary endothelium (RBC barrier)
Basememnt membrane (plasma protein barrier)
Slit processes of podocytes (plasma protein barrier)
```
33
What barriers exist for blood filtration in the glomerulus?
```
Glomerular capillary endothelium (RBC barrier)
Basememnt membrane (plasma protein barrier)
Slit processes of podocytes (plasma protein barrier)
```
34
What is the normal GFR?
125ml/min
35
What is the extrinsic regulation of the GFR?
Sympathetic control via the baroceptor reflex
36
How is the GFR intrinsically controlled?
Myogenic mechanism and tubuloglomerular mechanism which prevent short term ABP changes affecting the GFR
37
How does myogenic regulation work to control the GFR?
If vascular smooth muscle is stretched (increased ABP), it contracts thus constricting the arteriole
38
How does the tubuloglomerular mechanism work to control the GFR?
If the GFR rises, more NaCl flows through the tubule, leading to constriction of afferent arterioles
39
What is plasma clearance?
A measure of hoe effectively the kidneys can clean the blood.
40
How can plasma clearance be calculated?
Rate of excertion/ Plasma conc.
=
{X}urine x Vu/ {X}plasma
41
How can plasma clearance be calculated?
Rate of excertion/ Plasma conc.
=
{X}urine x Vu/ {X}plasma
42
What is the rate of inulin clearance compared to the GFR?
Inulin clearance = GFR
43
What is the rate of clearance of glucose?
0 - it is not secreted from the body
44
How does the rate of urea clearance compare to the GFR?
Urea clearance less than GFR
45
How doe sthe rate of H+ clearance compare to the GFR?
H+ clearance > GFR
46
How can renal plasma flow (RPF) be calculated?
Using para-amino hippuric acid (PAH)
47
Why is PAH good for measuring RPF?
It is freely filtered at the glomerulus
Secreted into the tubule
Completely cleared from the plasma
48
What should RPF be?
~650ml/min
49
What is the filtration fraction?
The fraction of plasma flowing through the glomeruli that is filtered into the tubules
50
How can the filtration fraction be calculated?
GFR/RPF
51
How can the filtration fraction be calculated?
GFR/RPF
52
Roughly how may times per day is the plasma filtered?
65
53
What do the kidneys reabsorb 99-100% of in healthy individuals?
Fluid - 99
Salt - 99
Glucose
Amino acids
54
How much of the urea in the blood is reabsorbed by the kidneys?
50%
55
What percentage of creatinine is reabsorbed by the kidneys?
0%
56
How much filtered fluid is reabsorbed in the proximal tubule?
80ml/min
57
What substances are reabsorbed in the PT?
```
Sugars
Amino acids
Phosphate
Sulphate
Lactate
```
58
What substances are secreted in the PT?
```
H+
Drugs and toxins
Hippurates
Neurotransmitters
Uric acid
Bile pigments
```
59
What are the 2 types of tubular reabsorption?
Transcellular
| Paracellular
60
What are the 2 types of tubular reabsorption?
Transcellular
| Paracellular
61
How is sodium transported into the epithelial cells of the proximal tubule?
Secondary active transport with glucose/amino acids
62
What is the function of the loop of Henle?
Generates a cortico-medullary solute conc. gradient
| Enabling formation of hypertonic urine
63
What happens the the ascending limb of the loop of Henle?
Na+ and Cl- are reabsorbed
| Water cannot easily permeate
64
What happens in the descending limb of the loop of Henle?
does NOT reabsorb NaCl
| Is highly permeable to water
65
What ions are involved in the triple transporter?
K+
Cl-
Na+
66
Is fluid leaving the proximal tubule hypo, iso, or hyper tonic?
Isotonic
67
Is fluid entering the distal tubule hypo, iso, or hyper tonic?
Hypotonic
68
How does urea contribute to ~1/2 of the medullary osmolality?
Urea cycle adds solute to the interstitium
Distal tubule not permeable to urea
Urea diffuses passively into loop
69
How does urea contribute to ~1/2 of the medullary osmolality?
Urea cycle adds solute to the interstitium
Distal tubule not permeable to urea
Urea diffuses passively into loop
70
What is the purpose of countercurrent multiplication?
To concentrate the medullary ISF, enabling the kidney to produce different urine volumes and concs. according to the amounts of circulating ADH
71
How does ADH affect the distal tubules and the collecting ducts?
Increases water reabsorption
72
How does aldosterone affect the distal tubules and the collecting ducts?
Increases sodium reabsorption
| Increases H+/K+ secretion
73
How does atrial natriuertic hormone affect the distal tubules and the collecting ducts?
Decreases Sodium reabsorption
74
How does PTH affect the distal tubules and the collecting ducts?
Increases Calcium reabsorption
| Decreases phosphate
75
How does PTH affect the distal tubules and the collecting ducts?
Increases Calcium reabsorption
| Decreases phosphate
76
What happens in the early distal tubule with ions?
Na+K+2Cl- transport
77
What happens the the late distal tubule with ions?
Calcium reabsorption
H+ secretion
Na+ and K+ reabsorption
78
What does aldosterone do in the late distal tubule?
Causes K+ secretion when the K+ secretory cells are activated
79
What happens in the early collecting duct?
Calcium reabsorption
H+ secretion
Na+ and K+ reabsorption
80
What happens in the late collecting duct?
There is low ion permeability and permeability to water is determined by ADH secretion
81
What happens in the late collecting duct?
There is low ion permeability and permeability to water is determined by ADH secretion
82
From what and where is ADH synthesised?
Octapeptide by the hypothalamus is transported down nerves where it is stored in granule form in the posterior pituitary gland
83
Where is ADH released into and what does it cause to happen?
Released from the posterior pituitary into the blood where APs down nerves lead to Ca2+-dependant exocytosis
84
What is the plasma half-life of ADH?
10-15mins
85
What effect does ADH have on the collecting duct membranes?
Increases their permeability to H20 by inserting aquaporins
86
What happens when there is maximal ADH concentration in the plasma?
Water moves from the collecting duct lumen along the osmotic gradient into the ISF thus enabling creation of hypertonic urine
87
How does urine travel from the kidneys to the bladder?
Propelled down the ureters by peristalic contractions
88
What is the micturition reflex?
Once the bladder has 250-400mls urine in it, stretch receptors in the wall of the bladder cause involuntary emptying of the bladder by bladder contraction and opening both the internal and external urethral sphincters
89
How can the micturition reflex be overridden?
Through voluntary control of the external sphincter
90
How can homeostasis of body fluid be obtained?
Monitoring and regulation of ECF osmolarity and volume
91
How is filtration in the kidneys regulated?
Changes in BP and the size of the filtration slits (podocytes)
92
What regulates the secretion/absorption in the kidneys?
Changes in solute conc.
93
What regulates the excretion function of the renal system?
Bladder function under neural control
94
How does activation of stretch receptors in the upper GI tract affect ADH?
Exerts a feed-forward inhibition of ADH
95
What effect does nicotine have on ADH?
Stimulates release
96
What effect does alcohol have on ADH?
Inhibits release
97
What effect does alcohol have on ADH?
Inhibits release
98
How does salt imbalance manifest itself?
Changes in ECFV
99
What regulates the amount of Na+ reabsorbed?
RAAS
100
In relation to ion concentrations when is aldosterone secreted?
When K+ conc rises or Na+ conc falls (or activation through RAAS)
101
What does aldosterone stimulate to occur in the kidney?
Na+ reabsorption
| K+ secretion
102
How does the JGA control rennin release?
Reduced BP in the afferent arteriole stimulates rennin release
Low NaCl detected by the macula densa cells stimulates rennin release
Sympathetic activity on the granular cells, causes them to release rennin
103
How does the JGA control rennin release?
Reduced BP in the afferent arteriole stimulates rennin release
Low NaCl detected by the macula densa cells stimulates rennin release
Sympathetic activity on the granular cells, causes them to release rennin
104
What can an abnormal increase in the RAAS system cause?
Hypertension
105
How is hypertension caused by RAAS stimulation treated?
Low salt diet
Loop diuretics
ACEIs
106
What does ANP stand for?
Atrial Natriuretic Peptide
107
What produces ANP and where is it stored until use?
The heart stores it in atrial muscle use until it is needed
108
What causes ANP release?
Mechanical stretching of the atrial muscle cells due to increased PV
109
What are the effects of ANP on the body?
Excretion of Na+ and diuresis
| Lowers BP
110
What is the role of erythropoietin released from the kidney?
Stimulates stem cells to produce more RBCs to increase the O2 supply in tissues if this is too low
111
How can pH be calculated?
log*1/{H+}
112
What is the pH of arterial blood?
7.45
113
What is the pH of venous blood?
7.35
114
What can acidosis do to the CNS?
Leads to depression of CNS
115
What can alkalosis do to the CNS?
Leads to overexcitability of the NS and then CNS
116
What do changes in {H+} affect in the body?
Enzyme activity
| K+ levels
117
What 3 sources constantly supply the body with H+?
Carbonic acid formations
Inorganic acids produced during the breakdown of nutrients
Organic acids from metabolism
118
What makes up a buffer system?
A pair of substances, one of which can yield free H+ as {H+} decreases; and one which can bind free H+ as {H+} increases
119
What makes up a buffer system?
A pair of substances, one of which can yield free H+ as {H+} decreases; and one which can bind free H+ as {H+} increases
120
What is the most important physiological buffer system?
The CO2-HCO3 buffer
121
How does the kidney affect the plasma conc. of HCO3-
Varies the amount reabsorbed depending on need
| Can also add new HCO3- to the blood (by excreting acid there is a net gain of HCO3-)
122
What does H+ secretion from the tubule do?
Drives absorption of HCO3-
Forms acid phosphate
Forms ammonium ions
123
What is the vast majority of H+ secretion used for?
HCO3- reabsorption to prevent acidosis occuring
124
What does excretion of acid phosphate (Titratable acid) and NH4+ do?
Rids the body of excess acid and regenerates the NCO3- buffer stores
125
What is compensation of an acid-base disturbance?
Restoration of pH to normal regardless of what happens to pCO2 and {HCO3-}p
126
What is correction of an acid base distrbance?
Restoration of pH AND pCO2 and {HCO3-}p to normal levels
127
What is correction of an acid base distrbance?
Restoration of pH AND pCO2 and {HCO3-}p to normal levels
128
What happens immediately following a blood pH change?
There is immediate dilution of the acid or base in ECF
129
What conditions can cause a retention of CO2 by the body (resp acidosis)?
```
Chronic bronchitis
Chronic emphysema
Airway restriction
Chest injuries
Respiratory depression
```
130
What happens to {H+}p in acidosis?
It rises
131
What indicates uncompensated respiratory acidosis?
pH less than 7.35 and PCO2 > 45mmHg
132
What drives the compensation is respiratory acidosis?
Renal system
133
How does the renal system manage to compensate for a respiratory acidosis?
H+ secretion is stimulated and all filtered HCO3- is reabsorped
H+ continues to be secreted and generates TA and NH4+
Acid is excreted and "new" HCO3- is added to the blood
134
How is respiratory acidosis CORRECTED?
Restoring normal ventilation and lowering PCO2
135
What is respiratory alkalosis?
Excessive removal of CO2 by the body
136
In what conditions does respiratory alkalosis occur in?
Low inspired PO2 at altitude
Hyperventilation
Hysterical overbreathing
137
What happens to {H+}p in respiratory alkalosis?
Decreases
138
How is uncompensated resp alkalosis defined?
If pH >7.45 AND PCO2 is less than 35mmHg
139
How is uncompensated resp alkalosis defined?
If pH >7.45 AND PCO2 is less than 35mmHg
140
How does the renal system compensate for resp. alkalosis?
HCO3- is excreted and the urine is alkaline
| No "new" HCO3- is added to the blood
141
How is resp. alkalosis CORRECTED?
Restoration of normal ventilation
142
What is metabolic acidosis?
Excess H+ from any source other than CO2
143
What can cause a metabolic acidosis?
Ingestion of acids/acid-producing foodstuffs
Excessive metabolic production of H+ (lactic acid build up)
Excessive loss of base from the body (diarrhoea)
144
What happens to {HCO3-}p in metabolic acidosis?
It falls
145
How is uncompensated metabolic acidosis defined?
pH less than 7.35 and {HCO3-}p is low
146
How does the body compensate for metabolic acidosis?
Ventilation quickly increases to blow off more CO2
147
What is {H+}p in metabolic acidosis?
Low
148
How is metabolic acidosis corrected?
New HCO3- is generated due to H+ secretion continuing
An acid load is excreted and {HCO3-}p is restored
Ventilation can then be normalised
149
How is metabolic acidosis corrected?
New HCO3- is generated due to H+ secretion continuing
An acid load is excreted and {HCO3-}p is restored
Ventilation can then be normalised
150
What is metabolic alkalosis?
Excessive loss of H+ from the body
151
What can cause a metabolic alkalosis?
Loss of HCl from the stomach (vomitting)
Ingestion of alkali or alkali-producing foods
Aldosterone hypersecretion (causes increased acid secretion and excretion)
152
What happens to {HCO3-}p in metabolic alkalosis?
Increases
153
How can uncompensated metabolic alkalosis be defined?
pH >7.45 or increased {HCO3-}
154
How does the body compensate in metabolic alkalosis?
Slowing ventilation, thus more CO2 is retained
155
How is metabolic alkalosis corrected?
HCO3- is secreted in urine and the plasma conc falls back to normal
156
How does GN show?
Glomerular tufts with secondary tubulointestinal changes
Non-infective
Usually diffuse but can be focal
Immunological mechanisms are often implicated but there is no single cause
157
What is pyelonephritis?
A bacterial infection of the renal pelvis, calyces, tubules and interstitium
May be acute or chronic with patchy distribution
E.coli most common organism
Other causes include psuedomonas and strep. faecalis
Much commoner in females
158
What is the pathogenesis of nephritis
Blood-borne (rare) in septicaemia, post surgery
| Ascending infection - cystitis is often present
159
What are the risk factors for developing nephritis?
```
Young and female
obstruction
pregnancy
diabetes
instrumentation
Vesico-ureteric reflux (VUR)
```
160
How does acute polynephritis appear macroscopically?
Ulcers on kidney tissue
161
How does acute polynephritis appear microscopically?
Renal tubules have neutrophil polymorphs
162
How does chronic pyelonephritis present?
Often no UTI history
Vague symptoms
Hypertension and/or uraemia
Large urine volumes
Renal imaging shows coarse cortical scarring and distortion of calyces
Kidneys may shrink
Lymphocytes and plasma cells on histology
163
How does tuberculous polynephritis present?
Haematogenous spread from lungs
Weight loss, fever, loin pain and dysuria
Sterile pyuria
Caseous foci
164
What organisms can cause cystitis?
E.coli
Klebsiella
Proteus
Pseudomonas
165
How does cystitis present?
Acute inflammation
166
What can cause a urinary tract obstruction?
Stricture, posterior urethral valves, prostatic disease
| Hypertrophy of detrusor muscle
167
What is hydronephrosis?
Dilation of the pelicalcyceal system with parenchymal atrophy
168
What are the unilateral causes of hydronephrosis?
Calculi
Neoplasm
Pelvi-ureteric obstruction
Strictures
169
What are the bilateral causes of hydronephrosis?
Urethral obstruction
VUR
Neurogenic disturbance
Bilateral obstruction
170
What are the bilateral causes of hydronephrosis?
Urethral obstruction
VUR
Neurogenic disturbance
Bilateral obstruction
171
What is agenesis of the kidneys?
absence of 1 or both kidneys
172
What is hypoplasia of the kidneys?
Small kidneys but normal development
173
What is a "horseshoe" kidney?
Fusion at either kidney pole - usually lower
174
What is a duplex system?
More than 1 ureter of part of kidney on 1 side
175
How do simple kidney cysts present?
v.common with usually no functional disturbance
may be multiple and large
May occur secondary to long standing kidney disease
176
How does infantile PCKD present?
Rare with various subtypes
AR inheritance
Uniform bilateral renal enlargement
Elongated cysts - dilatation of medullary collecting ducts
Reniform shape maintained
Associated with congenital hepatic fibrosis
177
How does adult PCKD present?
AD inheritance with a defect on chromosome 16 or 4
Mid-life as an abdo mass, haematuria, hypertension and CKD
Massive bilateral kidney enlargement
Multiple cysts of varying sizes
Reniform structure distorted
178
Other than in the kidneys, where other can cysts from adult PCKD present?
In 1/3 cases:
Liver
Pancreas
Lung
179
What vascular disorder is PCKD associated with?
Berry aneurysms in the circle of Willis --> subarachnoid haemorrhage
180
What are the benign types of renal tumours?
Fibroma
Adenoma
Angiomyolipoma
JCGT
181
How does a renal fibroma appear?
Medullary in origin
| White nodules
182
How does a renal adenoma appear?
yellowish nodules less than 2cm in size
| Cotrical origin
183
How does a renal angiomyolipoma appear?
Mixture of fat, muscle and blood vessels
May be multiple and bilateral
Associated with tuberoussclerosis
184
How does a renal JGCT appear?
Juxtaglomerular cell tumour
| Increased Rennin production leading to secondary hypertension
185
How does a renal JGCT appear?
Juxtaglomerular cell tumour
| Increased Rennin production leading to secondary hypertension
186
What are the malignant renal tumours?
Nephroblastoma (Wilm's tumour)
Urothelial carcinomas
Renal cell carcinoma
Transitional cell carcinoma
187
What is a nephroblastoma?
Commonest intra-abdo tumour in children
| Arises from residual primitive renal tissue
188
Where do urothelial carcinomas affect?
Renal pelvis and calyces
189
What is a Renal Cell Carcinoma?
Arises from renal tubule epithelium
Commonest primary renal tumour in adults
Commonest in males 55-60
190
How does a renal cell carcinoma present?
```
Abdo mass
Haematuria
Flank pain
Ploycythemia
Hypercalcaemia
```
191
What does a renal cell carcinoma look like?
A large well-circumscribed mass centered on the cortex
| Yellow with solid, cystic, necrotic and haemorrhagic areas
192
Where can renal cell carcinomas spread to?
Renal vein extension is common
| Lung and bone via blood
193
What is a transitional cell carcinoma?
Tumour from the transitional epithelium which accounts for 90% of all bladder tumours
194
What are the risk factors for developing transitional cell carcinoma?
```
Analine dyes
Rubber industry
Benzidine
Cyclophosphamide
Anagesics
SMOKING
```
195
How does a transitional cell carcinoma present?
Haematuria
| some occur ureteric obstruction and so those symptoms may also be present
196
What does a transitional cell carcinoma look like?
Papillary or solid
| Papillae have a thicker lining than normal urothelium
197
Where can a transitional cell carcinoma spread to?
local lymph nodes (obturator)
Lungs
liver
198
What is the commonest malignant bladder tumour in children?
Embryonal rhabdomyosarcoma
199
What tumours can affect the penis?
Squamous cell carcinoma in situ
| Bowen's disease - erythroplasia of Queyrat
200
What are the features of penile tumours?
Full thickness dysplasia of the epidermis
| Only 5% lead to invasive carcinoma
201
What is benigh nodular hyperplasia of the prostate (BPH)?
Irregular proliferation of both glandular and stromal prostatic tissue
202
How common in BPH?
At least 75% of men >70 are affected but only 5% are symptomatic
203
What can cause BPH?
Hormonal imbalance
Alteration of the androgen/oestrogen ratio
Central (peri-urethral) gland is involved (oestrogen responsive)
204
What can cause BPH?
Hormonal imbalance
Alteration of the androgen/oestrogen ratio
Central (peri-urethral) gland is involved (oestrogen responsive)
205
How can BPH affect the bladder sphincter mechanism
Physical obstruction
| Physiological interference - peri-urethral glands at the internal urethral meatus
206
What does prostatism cause?
Difficulty in starting micturition
Poor stream
Overflow incontinence
207
What are the complications of acute or chronic urinary retention?
Bladder hypertrophy
Diverticulum formation
If untrated may lead to hydroureter, hydronephrosis or infection
208
How is BPH managed?
Surgery (transurethral resection)
| Drugs (alpha-blockers, 5-alpha-reductase inhibitors)
209
How prevalent is prostate carcinoma?
Common
Responsible for 11% of cancer deaths in males
Peak incidence = 60-80
210
Where does prostate cancer originate from?
Periphera; ducts and glands esp. in the posteior lobe
| Peri-urethral zone may become involved at a later stage
211
How does prostate carcinoma spread?
Local - urethral obstruction, capsular penetration, seminal vesicles, bladder, rectum
Lymphatic - sacral, iliac, para-aortic nodes
Blood - bone, osteosclerotic mets lungs, liver
212
How does prostate carcinoma spread?
Local - urethral obstruction, capsular penetration, seminal vesicles, bladder, rectum
Lymphatic - sacral, iliac, para-aortic nodes
Blood - bone, osteosclerotic mets lungs, liver
213
How is prostate carcinoma diagnosed?
RP exam
Imaging - US, x-rays, DEXA
Biochem - PSA
Biopsy - 8-12 needle biopsies from US-guided trans-urethral resection
214
How is prostate carcinoma managed?
Hormonal therapy - anti-androgens. Oestrogens, cyproterone
Radiotherapy - for bone mets
Surgery - radical prostatectomy
215
How common are testicular tumours?
Relatively uncommon although incidence is rising
| 1% of all cancer deaths - commonest solid organ malignancy in young adult males
216
What is the usual clinical picture for testicular carcinoma?
Painless testicular enlargement
| May be associated with hydrocele, gynaecomastia or other common malignancy symptoms
217
What is a major risk of developing testicular tumours?
Undescended testes
218
What are the different types of testicular tumours?
Germ Cell Tumours (90%) - Seminoma, teratoma, mixed
Others - Lymphoma, leukaemia, stromal tumours, mets
Paratesticular tumours - adenomatoid tumour, sarcomas
219
What are the different types of testicular tumours?
Germ Cell Tumours (90%) - Seminoma, teratoma, mixed
Others - Lymphoma, leukaemia, stromal tumours, mets
Paratesticular tumours - adenomatoid tumour, sarcomas
220
What is a seminoma?
Commonest GCT (40%)
Occurs in 30-50y/o
Solid, homogenous, pale, macroscopic appearance (potato tumour)
Consists of large, clear tumour cells with variable stromal lymphocytic infiltrate
221
What are the variants of seminoma?
Spermatocytic and anaplastic
222
How can seminomas spread?
Lymphatic - para-aortic nodes
| Blood - lungs and liver
223
How are seminoma treated?
Radio/chemo
V. radiosensitive
>95% cure rate
224
What is the peak incidence for teratoma occurrence?
20-30y/o
225
How can teratomas appear macroscopically?
```
v variable
Solid areas
Cysts
Haemorrhage
Necrosis
```
226
What tumour markers exist to monitor treatments of seminomas and teratomas?
bHCG - trophoblastic componenets
AFP - yolk-sac componenets
PLAP - seminoma
227
What is the gross structure of the kidney?
Bean shaped organ
Encapsulated by dense collagen fibres
Has a cortex and a medulla
Medulla is divided into pyramids
228
What makes up a nephron?
Renal corpuscle and renal tubules
229
What makes up the renal corpuscle?
A tuft of capillaries called the glomerulus and the Bowman's capsule
230
What cell type makes up the Bowman's capsule?
Simple squamous epithelium
231
How does the thin limb of the loop of Henle appear histologically?
Simple squamous lining with nuclei protruding into the lumen
232
How does the thick ascending limb of the loop of Henle appear histologically?
cuboidal epithelial cells with absent mitochondria
233
What is the vasa recta?
A group of thin-walled blood vessels which dip down into the medulla from above and then climb back up to the cortex
234
What cell type lines the distal convoluted tubule?
Simple cuboidal epithelial cells
235
What cell type lines the collecting ducts?
Simple columnar epithelium
236
What is the macula densa?
On the side of the DCT nearest the afferent arterioles, the DCT cells are tall, crowded together and nuclei are intensily stained. These function in sensing ion composition in the DCT
237
What are juxtaglomerular cells?
Modified smooth muscle cells in the wall of the afferent arteriole which contain and secrete Rennin
238
What is the pathway of urine flow?
```
Produced at the renal papilla
Collected into the minor calyx
Flows into the major calyx
Renal Pelvis
Ureter
Bladder
Urethra
Exits the body
```
239
What cells line the conducting part of the urinary tract?
Transitional epithelium or Urothelium
240
What are the cells on the luminal surface of the urinary tract known as?
Umbrella cells - they are domed like umbrellas
| Have a thickened and inflexible membrane
241
What are the cells on the luminal surface of the urinary tract known as?
Umbrella cells - they are domed like umbrellas
| Have a thickened and inflexible membrane
242
What lies below the transitional epithelium of the urinary tract?
Lamina propria
| 2-3 layers of smooth muscle
243
What is the histological structure of the proximal ureter?
```
Internally = transitional epithelium
Middle = Thick layer of lamina propria
Externally = Thin layer of muscularis externa
```
244
What is the histological structure of the distal ureter?
Like proximal ureter but lamina propria is thinner and muscularis externa is thicker
245
What is the histological structure of the urinary bladder?
From internal to external:
Urothelium
Lamina propria
Thick layers of smooth muscle
246
What is the histological structure of the female urethra?
3-5cm length
| Transitional epithelium to a stratified squamous epithelium at its termination
247
What is the histological structure of the male urethra?
20cm length
Prostatic urethra = 3-4cm lined by a transitional epithelium
Membranous urethra = 1cm lined by a stratified columnar epithelium
Penile urethra = 15cm lined by stratified columnar and changing to stratified squamous at its termination
248
What is the histological structure of the prostate gland?
Tubulo-alveolar glands lined by a simple secretory columnar epithelium with a fibromuscular stroma
249
How does oedema occur?
An imbalance between the rate of formation and rate of absorption of ISF
250
What is the nephrotic syndrome?
A disorder of glomerular filtration which allows protein to appear in the filtrate
251
How does congestive HF cause oedema?
Expansion of blood volume due to low CO, leading to increased venous and capillary pressures
252
How does hepatic cirrhosis cause oedema?
Increased pressure in the hepatic portal vein, combined with decreased albumin production causes a loss of fluid into the abdo cavity
253
How does hepatic cirrhosis cause oedema?
Increased pressure in the hepatic portal vein, combined with decreased albumin production causes a loss of fluid into the abdo cavity
254
What drug blocks the Na+/H+ exchange which occurs in the PCT?
Carbonic Anhyrase inhibitors
255
What drug blocks the Na+/K+/2cl- co-transport in the ascending loop of Henle?
Loop diuretics
256
What drug blocks Na+/Cl- co-transport in the DCT?
Thiazide diuretics
257
What drug blocks the Na+/K+ exchange in the collecting tubule?
Potassium sparing diuretics
258
What is the site of action for many diuretics?
Apical membrane of tubular cells
259
What 2 transport systems exist for allowing drugs enter the filtrate to access the apical membrane of tubular cells?
Organic Anion Transporters (OATS)
| Organic Cation transporters (OCTs)
260
What type of drugs to OATs transport?
Acidic drugs e.g. thiazide and loop agents
261
What type of drugs do OCTs transport?
Basic drugs e.g. triamterene and amiloride
262
How do OATS work to allow acidic drugs to access the apical membrane of tubular cells?
At
263
How do OATS work to allow acidic drugs to access the apical membrane of tubular cells?
At the basolateral membrane, organic anions enter a cell by either diffusion or in exchange for alpha-ketogluarate via the OATS.
At the apical membrane organic anions enter the lumen via either MRP2 or OAT4.
264
How do OCTS work to allow acidic drugs to access the apical membrane of tubular cells?
At the basolateral membrane, organic cations enter the cell either by diffusion, or OCT
At the apical membrane, organic cations enter the lumen via either MDRP1 or OC+/H+ antiporters
