Kidney and urinary tract pathology Flashcards
1
Q
What is pathogenisis
A
What is the mechanism causing the disease
2
Q
What is aetiology
A
What causes the disease
3
Q
What is epidemiology
A
Who gets the disease
4
Q
What is renal cell carcinoma
A
Cancer of the kidney that arises from the renal tubular epithelium
5
Q
What are the most common types of renal cell carcinoma
A
Clear cell (75%) Papillary (10%)
6
Q
What is the epidemiology of renal cell carcinoma
A
60yo+ Male > female Family history PMH of: -Obesity -Smoking -NSAID use -ESRF and on dialysis
7
Q
What are paraneoplastic syndromes
A
Signs and symptoms that are not related to local effects of the primary or metastatic tumours
Develop as a result of either:
-proteins/ hormones secreted by tumour cells
-immune cross reactivity between tumour cells and normal tissues
8
Q
What are the clinical features of renal cell carcinoma
A
Local primary tumour effects:
- Haematuria
- Abdominal pain
Effects of distant metastases:
- Lung mets-> SOB etc
- Bone mets -> bone pain etc
Paraneoplastic syndromes:
- PNS are common in RCC and include:
- weight loss (cancer cachexia)
- Hypertension (renin)
- Polycythemia (EPO)
9
Q
What is Wilms’ tumour and who gets it
A
Nephroblastoma
Cancer of the kidney that arises from the nephroblasts (cells that develop into the kidney in embryological development)
Children under 5
10
Q
What are the clinical features of Wilm’s tumour
A
Abdominal distention
Haematuria
Mets are rare
PNS are rare
11
Q
What is urolithiasis
A
Urinary tract calculi/ stones
Stones forming in the lumen of the urinary tract, anywhere from renal calyx to bladder
12
Q
What are the types of urolithiasis
A
Calcium stones (70%) Urate stones (5%) Cystine stones (1%) Struvite stones (15%) (magnesium ammonium phosphate)
13
Q
What causes each type of urolithiasis
A
Too high a concentration of a solute in the urine
Calcium: hypercalcemia
Urate: gout, malignancy (high cell turnover)
Cystine: congenital cystinuria (kidneys unable to reabsorb amino acids)
Struvite: urinary tract infection
14
Q
What are the clinical features of urolithiasis
A
Pain: -Ureter: loin to groin -Bladder: lower abdominal -Urethra: dysuria Haematuria (blood in urine) Symptoms of complications Obstruction leads to renal impairment Urinary stasis leads to infection Local trauma leads to squamous metaphase and then SCC risk
15
Q
What is dysuria
A
Painful urination
16
Q
What is vesicoureteral reflux (VUR)
A
When urine flows backwards from the bladder to the ureter rather than from the bladder to the urethra
17
Q
What is the epidemiology of VUR
A
Young people especially <2yo
Those with family history of VUR
18
Q
What is the aetiology of VUR
A
Congenital abnormality of vesicoureteric junction
Shorter intramural ureter
19
Q
What is the pathogenesis of VUR
A
Ureter enters bladder at abnormal angle -> dysfunction of vesicoureteric junction -> when voiding, urine flows the wrong way
20
Q
What are the clinical features of VUR
A
Usually asymptomatic
Only symptoms of complications
Stasis: UTI
Back pressure and ascending infection - renal damage
21
Q
What are the clinical features of urothelial carcinoma
A
Haematuria Frequency, urgency, dysuria, urinary obstruction Lung mets - SOB Bone mets - bone pain Liver mets - jaundice PNS are rare
22
Q
What is urothelial carcinoma
A
Transitional cell carcinoma
Cancer of urothelial epithelium
Accounts for >90% of bladder cancer
23
Q
What is the epidemiology of urothelial carcinoma
A
Adults aged >60yo M>F Smokers Exposure to certain industrial chemicals Family history Treatment for other Cancer (pelvic radiotherapy, cyclophosphamide)
24
Q
What is a neurogenic bladder
A
Inability to properly empty the bladder due to neurological damage
Two types:
-Spastic if damage to brain or spinal cord (UMN)
Flaccid if damage to peripheral nerves (LMN)
25
What causes neurogenic bladder
UMN damage:
- stroke
- MS
- Spinal injury
LMN damage:
- Pregnancy
- Diabetes
- Alcohol
- B12 deficiency
26
What are the clinical features of neurogenic bladder
Symptoms of lack of control of bladder emptying:
- Urinary retention
- Abdominal distention
- Incontinence
- Urge
- Frequency
Symptoms related to complications:
-Stasis -> UTI -> dysuria
-Stasis -> urinary stones -> haematuria
Inability to empty bladder -> bladder distention -> hydroureter -> hyronephrosis -> renal function impairment -> oedema
27
What is benign prostatic hyperplasia
Increased number of both stroll and glandular cells in the prostate
Know by patients as an enlarged prostate
28
What is the epidemiology of benign prostatic hyperplasia
Old men
Obesity
Diabetes
Family history
29
What are the clinical features of benign prostatic hyperplasia
Lower urinary tract symptoms:
- Hesitancy or urgency
- Poor/ intermittent stream
- straining
- prolonged micturition (peeing)
- Incomplete bladder emptying
- Dribbling
- Frequency
- Incontinence
- Nocturia (waking in night to pee)
30
What is prostatic adenocarcinoma
Cancer of the glandular epithelium in the prostate
31
What is the epidemiology of prostatic adenocarcinoma
Old men
Black men
Family history (inc BRCA1 /2)
Pesticide exposure
32
What are the clinical features of prostatic adenocarcinoma
Lower urinary tract symptoms
Bone mets -> bone pain
PNS are rare
33
What is cryptochidism
Undescended testis where the testis is not in the scrotum
| Types based on site of testis
34
Who gets cryptorchidism
Premature babies
35
What are the clinical features of cryptorchidism
```
Empty scrotum
May resolve spontaneously or may develop complications:
-infertility
-hernias
-testicular cancer risk
-testicular torsion
```
36
What is seminoma
Malignant neoplasm of the testis arising from the germ cells in seminiferous tubules
Most common type of testicular cancer
37
Which forms of primary testicular tumour have a bad prognosis and so need more aggressive treatment
```
Teratoma
Choriocarcinoma
Yolk sac
Embryonal
Lymphoma
```
38
Which forms of primary testicular tumour have a good prognosis and so need less aggressive treatment
Classic seminoma
Spermatocytic seminoma
Leydig cell tumour (usually benign)
Sertoli cell tumour (usually benign)
39
What is the epidemiology of seminoma
Young men 25 - 45 yo
family history
Crytorchidism regardless of whether it was surgically corrected or only affected the other testis
40
What are the clinical features of seminoma
Testicular lump, swelling, pain
Lung mets - SOB
LN mets - back pain
Gynecomastia (BHCG)
41
What are the complications of Urinary tract obstruction
Irreversible renal impairment and secondary VUR due to back pressures
Infection and calculi formation due to urinary stasis
42
What are the renal functions
Eliminate metabolic waste products
Regulate fluid/electrolyte balance
Regulate acid-base balance
Produce hormones
43
What hormones are produced by the kidneys and what do they do
Renin: fluid balance (RAAS)
Erythropoietin: stimulates erythrocyte production
44
How does acute renal failure present
Unwell
| Rapid rise in creatinine and urea
45
How does nephrotic syndrome present
```
Always due to damage to glomerulus
Oedema
Proteinuria
Hypoalbuminaemia
+/- hypertension
+/- hyperlipidaemia
```
46
How does acute nephritis (nephritic syndrome) present
```
Oedema
Proteinuria
Haematuria
Hypertension
Renal failure
```
47
How does chronic renal failure present
Slow decline in renal function
48
How is renal pathology diagnosed
Renal physician: clinical history, examination
Biochemist: Blood tests (urea, creatinine), Urine analysis (Protein, blood, electrolytes)
Pathologist: Renal biopsy (Light microscopy, immunofluorescence, electron microscopy)
Urologist: Cytoscopy (obstruction, haematuria)
Radiologist: Radiology (obstruction, kidney size, structural abnormalities)
49
What is the blood flow of renal system
```
Branches of renal artery
Afferent arteriole
Glomerulus (capillary bed- network of capillaries)
Efferent arteriole
Branches of renal vein
```
50
What is thrombotic microangiopathy
Thrombi in capillaries/arterioles
| Endothelial damage by bacterial toxins, drugs, complement or clotting system abnormalities
51
What is vasculitis
Acute/chronic vessel wall inflammation with lumen obliteration
Various types affect different calibre vessels
52
What causes vascular damage
```
Hypertension
Diabetes
Atheroma
Thrombotic microangiopathy
Vasculitis
```
53
What are the complications of nephrotic syndrome
Infection
| Thrombosis
54
What are the common causes of nephrotic syndrome
Adults:
- Membranous nephropathy
- Focal segmental glomerulosclerosis (FSGS)
- Minimal change disease
- Diabetes
- Lupus nephritis
- Amyloid
Children:
- Minimal change disease (commonest)
- Focal segmental glomerulosclerosis
- Other causes are rare
55
What are the various possible causes of FSGS
Idiopathic or genetic
Heroin use
HIV
Male more than female
56
What are the causes of acute nephritis
Adults:
- Post infective glomerulonephritis
- IgA nephropathy
- Vasculitis
- SLE
Children:
- Post infective glomerulonephritis
- IgA nephropathy
- Henoch-Schönlein purpura (specific IgA nephropathy)
- Haemolytic-uraemic syndrome
57
How does acute renal failure present
```
Anuria/oliguria (<400ml/24h)
Raised creatinine and urea
Malaise
Fatigue
Nausea
Vomiting
Arrhythmias
```
58
What are the causes of acute renal failure
Pre-renal: reduced blood flow to kidney (severe dehydration, hypotension (bleed, septic shock, LVF)) (renal biopsy unhelpful)
Renal: damage to kidney (renal biopsy can be helpful)
Post-renal: urinary tract obstruction (urinary tract tumours, pelvic tumour, calculi, prostatic enlargement) (renal biopsy unhelpful)
59
What are the adult causes of acute renal failure
Vasculitis
| Acute interstitial nephritis/ tubulointerstitial nephritis (tubular damage with inflammation usually due to drugs)
60
What are the children causes of acute renal failure
PIGN
Henoch-Schönlein Purpura
Haemolytic uraemia syndrome
Acute interstitial nephritis
61
What are potential complications of acute renal failure
```
Cardiac failure (fluid overload)
Arrhythmias (electrolyte imbalance)
GI bleeding (multifactorial)
Jaundice (hepatic venous congestion)
Infection (especially lung and urinary tract)
```
62
What is chronic renal failure
Permanently reduced GFR
| Reduced number of functional nephrons
63
What are the stages of chronic renal failure
Stage 1: Normal/increased GFR (>90ml/min/1.73m2)
Stage 2: Mild GFR reduction (60-89ml/min/1.73m2)
Stage 3: Moderate GFR reduction (30-59ml/min/1.73m2)
Stage 4: severe GFR reduction (15-29ml/min/1.73m2)
Stage 5: Kidney failure (GFR <15ml/min/1.73m2 or dialysis)
64
What chronic conditions cause chronic renal failure
Adults:
-Dibetes
Children:
-Developmental abnormalities/ malformations
Both:
- Glomerulonephritis
- Reflux nephropathy (repeated infections/scarring)
65
What is isolated proteinuria and what causes it
```
No allied haematuria, renal failure or oedema
May be benign
May be due to renal disease:
Adult: FSGS, DM, SLE
Children: FSGS, HSP
```
66
What causes isolated haematuria
IgA nephropathy
Thin basement membrane disease
Alport hereditary nephropathy
67
What are the mechanisms of damage to kidneys due to hyperglycaemia in diabetics
Damaged basement membrane thickens and glomerulus produces excess extracellular matrix (nodules)
Small vessel damage causes ischaemia and tubular damage
68
What is a myeloma
Plasma cell tumour
Excess Ig deposit in tubules cause inflammation and fibrosis
Renal tubule loss causes irreversible decline in renal function
69
What is a UTI
An infection of any part of the urinary system
70
What is an infection
The invasion of body tissues by a pathogenic organism which causes an immune response, giving rise to symptoms
71
What causes a UTI
Usually an endogenous bacteria which has got in the wrong place and invaded
72
Who are at higher risk of UTIs
```
Female
Pregnant
Patients with:
-Prostatic hypertrophy
-Stones
-Strictures
-Neoplasia
-Residual urine
Urological instrumentation (including catheters)
Sexual intercourse
Fistulae: Recto-vesical, vesico-vaginal
Congenital abnormalities: vesico- ureteric reflux
```
73
Which areas of the Urinary tract have bacteria and which are sterile
Sterile: kidney, ureter and usually the bladder (sometimes not though)
Colonised: urethra (perineal flora)
74
What makes up perineal flora
Skin flora: mainly coagulase negative staphylococci
Lower GI tract flora:
-internal colonising bacteria found on skin around relevant orifice
-Anaerobic bacteria
-Aerobic bacteria
--Enterobacterales (coliforms, enteric gram negative bacilli)
--Gram positive cocci
---Enterococcus spp
75
What is asymptomatic bacteriuria
No symptoms of a urinary tract infection but cultured urine sample grows a single organism in significant numbers
76
What are the symptoms of cystitis (lower UTI) and who is most likely to contract it
```
Dysuria
Frequency
Urgency
Supra-pubic pain or tenderness
Polyuria, nocturne, haematuria
More common in women
```
77
What are the symptoms of an infection of the kidney or renal pelvis
```
Dysuria
Frequency
Urgency
Supra-pubic pain or tenderness
Polyuria, nocturne, haematuria
More common in women
Loin/abdominal pain or tenderness
Fever
Signs of systemic infection:
-rigors, nausea, vomiting diarrhoea
-Elevated CRP, WBC
```
78
What is a complicated UTI
```
Underlying abnormality to structure or function
Urinary stasis
Presence of foreign body:
-catheter/other device/renal calculi
-biofilm
-Children <10-12
-Men <65
```
79
What is Urosepsis
Systemic signs of infection related to any underlying urinary source of infection
80
What are other causes of urethritis
STIs (gonorrhoea)
Thrush can cause irritation and symptoms such as dysuria
Urethral syndrome
81
What is urethral syndrome
Symptoms of Lower UTI without infection
82
What are the types of Urinary tract abscesses
Perinephric
| Intra-renal
83
What is prostatitis
Inflammation of prostate
84
How does acute bacterial prostatitis present
Lower urinary tract symptoms
Fever
Tender tense prostate on PR palpation
Acute retention
85
What are the risk factors for acute bacterial prostatitis
Procedures involving the prostate:
-Trans-urethral resection of prostate (TURP)
-Trans-rectal ultra-sound guided (TRUS biopsy)
Indwelling urinary catheter
86
Which pathogens usually cause acute bacterial prostatitis
Typically normal urinary pathogens (E.coli)
| Can be caused by S. aureus
87
How does chronic prostatitis present
Pain inland around the perineum and genitalia
Lower urinary tract symptoms
Enlarged or tender prostate on examination
88
What causes chronic prostatitis and how are the causes distinguished
>90% due to chronic pelvic pain syndrome:
- Negative urinary culture
- Non-bacterial
Chronic bacterial prostatitis:
- Recurrent UTIs with the same organism
- Asymptomatic in-between
89
What are the points of clinical tests
To confirm clinical suspicion
To find out the pathogen and how best to treat it
Monitor response
90
What is imaging used for in UTIs
Is the Urinary tract anatomically normal?
Are there stones?
Is there an abscess
91
What are the microbiological investigations available for UTIs
Dipsticks/Ward tests? Urinalysis
| Laboratory testing of urine samples
92
What do the ideal renal function tests do
Detect renal damage
Monitor functional damage
Distinguish between impairment and failure
93
How is it known when the kidney functioning system is broken
No urine output
Clinical symptoms
Tests
94
What is the flow for kidney function
Input arterial-> filter -> processor -> output venous/ output urine
95
What are the lab tests for renal function
```
Glomerular filtration rate
eGFR
creatinine clearance
plasma creatinine
plasma urea
urine volume
urine urea
urine sodium
urine protein
urine glucose
haematuria
```
96
What is Oliguria
Abnormally low urine volume
| 24 hour volume less than 400ml
97
When is a patient considered anuric
No or little urine, less than 100ml/24hr
98
When does a patient have polyuria
Urine volume greater than 3 litres per day and not drinking.
99
Which factors influence plasma urea conc
```
GIT protein
Liver amino acids
Tissue protein
Distribution volume
Kidney reabsorption excretion
Kidney filtration
```
100
What does urea excretion show
60% of urea is usually excreted with the rest being absorbed passively by the renal tubules
Rate of reabsorption depends on rate of tubular flow
More urea is reabsorbed if the flow rate is slow as there is more time for urea to diffuse into the peritubular capillaries
Tubular flow rate is slow when there is renal hypoperfusion
101
What causes increased plasma urea
```
GI bleed
Trauma
Renal hypoperfusion
Decreased RBF
Decreased ECFV
Acute renal impairment
Chronic renal disease
Post-renal obstruction calculus tumour
```
102
What is the normal range of plasma creatinine and when should it be measured
50-140 umol/l
| 8 hours after a meal as evidence of increased conc after meat ingestion
103
What does an increase in plasma creatinine mean
GFR decreased a large amount
| In chronic renal disease it may increase to as high as 1000umol/l
104
How do physicians predict when a patient will require dialysis or transplantation
Plot the reciprocal of the plasma creatinine conc which is linear and then extrapolate
105
When is Glomerular filtration rate measured
No often as requires patient to come to hospital
People considering donating a kidney whilst alive
Before administering a potentially toxic drug before chemo
106
How is GFR measured
Used to be by calculating the clearance of insulin but now radioactive substances are used
107
How is creatinine clearance measured
(Urine creatinine conc m/mol/l x urine volume)/ plasma creatinine conc umol/l
