Renal Flashcards

1
Q

Pre-renal causes of renal disease

A

Decr blood flow to kidneys:

  • Shock
  • Heart Failure
  • Hypotension
  • Renal artery stenosis
  • Dehydration
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2
Q

Renal Causes of Renal Disease

A

GN (nephritic/nephrotic)

ATN

Interstitial disease

  • Vascular (vasculitis, thrombus/dissection)
  • Infiltration (sarcoid, Tb)
  • Systemic (SLE, DM)
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3
Q

Post-renal causes of renal disease

A

Urinary tract obstruction:

  • prostate obstruction
  • strictures
  • stones
  • clots
  • malignancy
  • sloughed papillae occluding lumen (DM)
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4
Q

Causes of glomerular nephritis

A
Autoimmune (SLE, HSP)
Drugs
Infection
Malignancy
Primary GN
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5
Q

Causes of ATN

A

Pre-renal damage

Nephrotoxins (aminoglycosides)
Contrast medium
Rhabdomyolysis (muscle breakdown) !!

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6
Q

Interstitial disease causes

A

Drugs (penicillin allergy)

Infiltration (lymphoma, infection-Tb, post-chemo, Sarcoid)

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7
Q

Causes of renal vascular damage to kidneys

A

Vasculitis
Malignant HTN
Large vessel occlusion (thrombus, dissection)

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8
Q

What does a urine dipstick detect?

A

Leucocytes
Nitrates
Blood
Protein

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9
Q

RAAS

A

JGA detects decr in renal perfusion -> activates RAAS:
Renin secreted from kidneys -> converts angiotensinogen to angiotensin 1 -> ACE converts angiotensin 1 to angiotensin 2 -> Ang II does the following to incr BP:

  1. incr symp activity
  2. Incr Na/H20 reabsorption; incr K excretion
  3. Aldosterone secretion from adrenals
  4. Vasoconstriction to increase BP
  5. ADH/vasopression secretion from posterior pituitary -> aquaporins inserted into collecting duct increases Na reabsorption

1-5 increase circulating volume and BP leading to reperfusion of JGA

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10
Q

What is the commonest renal cause of kidney disease?

A

ATN

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11
Q

Nephrotic Syndromes

A
  1. Membranous nephropathy most common cause for adults
  2. Minimal change disease most common cause for kids
  3. FSGS
  4. Membranoproliferative GN
  5. Secondary causes due to hepB/C, SLE, NSAIDs, neoplastic syndrome, diabetic nephropathy, amyloidosis
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12
Q

Nephritic Syndromes

A
  1. IgA nephropathy most common cause for adults
  2. Post-infectious (strep) GN
  3. Rapidly progressive GN (IgA, vasculitis, anti-GBM/Goodpastures GN)
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13
Q

Ways to evaluate volume status

A

Capillary refill, Mucus membranes and skin turgur, urine output

Peripheral oedema, JVP

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14
Q

What is the protein deposited in the kidneys in Multiple Myeloma called?

A

Bence Jones Protein or M protein (light chains) or paraprotein

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15
Q

Blood tests in kidney disease

A
UE
FBC
LFT
Clotting
CRP
ABG 
If systemic cause suspected: Ig and paraprotein electrophoresis, C3/C4, autoantibodies (ANCA, ANA, Anti-GBM), blood culture
- low C3 indicates immunological cause
- low C4 indicates SLE
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16
Q

Investigations for kidney malfunction

A

Renal USS shows cysts/small kidneys/masses
CTKUB: obstruction (non-contrast) or IVU (contrast for strictures)
XRKUB: stones

Urine dipstick (proteinuria, haematuria)

Urine spot test (microalbuminuria)

Urine MCS (glomerular in origin, infection?)

Renal biopsy -> immunohistochemistry

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17
Q

Signs of chronic kidney disease

A
Small kidneys on USS
Anaemia
Low Ca, high PTH
High phosphate 
High creatinine/low GFR
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18
Q

Complications of AKI

A
  1. Electrolyte imbalance: Hyperkalaemia, hypnatraemia
  2. Acid base: metabolic Academia
  3. Fluid balance: Pulmonary Oedema from fluid overload (need diuretics or dialysis)
  4. Uraemia (need dialysis at this stage)
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19
Q

Nephritic syndrome criteria

A
Haematuria mostly
Oedema
HTN
Mod-severe decr GFR
Non-nephrotic range proteinuria
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20
Q

Nephrotic syndrome criteria

A

Proteinuria mostly
Hypoalbuminaemia -> pitting oedema
Hypercholesterolaemia
Normal-mild decr GFR

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21
Q

Most common cause of childhood nephrotic syndrome and prognosis/treatment

A

Minimal change disease

- Good prognosis with steroids

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22
Q

Most common cause of adult nephrotic syndrome and prognosis/treatment

A

Membranous nephropathy (primary/secondary causes)

Prognosis: 1/3 get better on own w supportive care; 1/3 relapse/remit; 1/3 progressive renal failure

Treatment: BP control, supportive measures only

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23
Q

Complications of CKD

A

CV disease leading cause of death due to poorer prognosis after AMI

Dyslipidaemia

Oedema

Metabolic Acidosis due to increased H retention

Anaemia due to Epo deficiency and decreased RBC survival time

Hyperkalaemia due to reduced K excretion

CKD mineral and bone disorder due to incr PO4 which suppresses Ca which stimulates rise in PTH to stimulate Ca resorption from bone -> SECONDARY HYPERPARATHYROIDISM and calcification of soft tissues and vasculature

Vitamin D deficiency due to inability to add the second OH onto 25 hydroxyvitamin D -> OSTEOMALACIA

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24
Q

What are medications that impair K excretion?

A

K sparing diuretics
ACE inhibitors
NSAIDs

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25
Treatment of CKD mineral and bone disorder
Phosphate binders (prevent dietary absorption of PO4) + Restrict dietary PO4 (milk, cheese, eggs) 1,25 OH Vit D analogues Cinacalcet (allosteric activator of Ca-sensing R on body tissues) +/- subtotal parathyroidectomy
26
Hyperkalaemic ECG changes
Widened QRS Tall peaked T waves Depressed ST segment
27
Treatment of CKD metabolic acidosis
Sodium bicarbonate
28
Lifestyle factors to adjust in CKD
SNAP: smoking, nutrition, alcohol, physical activity
29
Nephrotoxic drugs
``` ACE inhibitors NSAIDs Amino glycosides (gentamycin) Amphotericin (anti-fungal) Lithium IFNalpha ``` + penicillin (allergic interstitial nephritis), flucloxacilin (in pre-existing RF), BActrim
30
Role of PTH including the organ that produces it
Parathyroid gland produces PTH when serum Ca low -> leads to bone resorption of Ca to incr serum Ca -> inhibits PTH production
31
What is the active form of vitamin D called?
1,25 hydroxyvitamin D3
32
How is the active form of vitamin D produced?
Vitamin D is made in the skin as calcitriol and converted to cholecalciferol or vitamin D3 via sunlight -> liver hydroxylates this to 25-hydroxyvitaminD3 and then kidney adds a second OH to form 1,25 hydroxyvitaminD3
33
Actions of 1,25 hydroxyvitamin D3
Increased intestinal absorption of Ca and Phosphate Incr Bone mineralisation Incr bone resorption (remodelling) Immunity Muscle and bone health/strength
34
What happens if you are deficient in vitamin D?
Can result from lack of sunlight exposure. Leads to bone softening diseases such as Osteomalacia (Adults) Ricketts (kids)
35
Pathology seen in glomerulonephritis
Acute: - proliferation of mesangial or endothelial cells - WBC infiltration - Crescent formation - Ab deposition, immune complex formation, C' activation Chronic: - Hyalinosis - Sclerosis - BM thickening
36
What is the definition of rapidly progressive GN?
ARF + blood and protein in urine (nephritic)
37
What is the definition of chronic glomerulonephritis
CRF caused by glomerulonephritis + HTN + proteinuria + SMALL AND SHRUNKEN KIDNEYS
38
What is the most common cause of macroscopic haematuria?
UTI
39
What is the most common adult glomerulonephritis? and common symptoms of this
IgA nephropathy (may be asymptomatic/have macroscopic haematuria or nephritic syndrome)
40
What is the pathophys of IgA nephropathy?
IgA + C3 forms immune complexes and deposits in mesangial cells Mesangial proliferation
41
What is the treatment for IgA nephropathy?
Ace inhibitors or ARBs to lower bP and thus amt of protein in urine Fish oils Corticosteroids with rapidy progressive RF
42
What electrolytes are commonly deranged in kidney disease?
Na, K, Ca Phosphate and Mg
43
What hormones control sodium?
Aldosterone - Na/K exchange in DCT Angiotensin Renin
44
What hormone controls water content and how?
Vasopressin/ADH Inserts aquaporins in collecting duct.
45
Where is ADH made and secreted from?
Made in hypothalamus, stored and secreted in posterior pituitary
46
Where is aldosterone secreted from?
Adrenal cortex
47
What determines serum osmolarity?
Na K Glucose Urea
48
Difference btw AKI and CKD in terms of - definition - urine output - SX
AKI: low urine output with general SX of malaise (nausea, vomiting etc) - rapid reduction in kidney function over hours to days as measured by increase in serum urea and creatinine (>x1.5 baseline) CKD: normal to high urine output with NO SX due to adaptation - Impaired renal function (evidence of renal damage) >3mo ○ Microalbuminuria ○ Proteinuria ○ Glomerular haematuria ○ Pathological abnormalities on renal biopsy ○ Anatomical abnormalities (cysts on ultrasound etc) - OR GFR <60ml/min/1.73m^2 for >3 mo with or without evidence of kidney damage
49
Complications of nephrotic syndrome
- susceptible to infection (loss of Ig in urine, and steroid use) - hyperlipidaemia - hyper coagulable state -> incr risk of VTE
50
What do you think of if a patient presents with haematuria a few weeks after infection?
post-strep glomerulonephritis
51
What do you think of when a patient presents with a purpuric rash and macroscopic haematuria?
Hence Schonlein -> IgA nephropathy
52
What do you think of when a patient presents with a purpuric rash and macroscopic haematuria?
Henoch Schonlein -> IgA nephropathy
53
At what stage do patients need dialysis or renal transplant?
Stage 5 CKD (when eGFR<15ml/min) = ESRF
54
What are the various stages of CKD at what stage do sx/signs become evident?
1-2: GFR is >60 with evidence of renal damage (proteinuria, haematuria or abnormal anatomy or systemic disease) 3: GFR 30-60 with/without evidence renal damage 4: GFR 15-30 *Sx/signs* 5: ESRF (GFR<15) *sx/signs*
55
SYMPTOMS of CRF
Polyuria, nocturia +/- Macroscopic haematuria Uraemia symtoms - lethargy, malaise - fluid overload - pruritus - seizures and restless legs + peripheral neuropathy - anorexia, N&V
56
Broad classes of causes of CRF
1. Diabetic nephropathy (2>1) 2. Glomerulonephritis - IgA nephropathy, membranous nephropathy, FSGS 3. Hereditary disorders (PCOS, familial nephritis, reflux nephropathy) 4. Analgesic (drugs) -> interstitial nephritis - most commonly chronic NSAID overuse (women in 50s and 70s) 5. Hypertensive nephrosclerosis
57
What are the histopathological features of diabetic nephropathy
- Arterial hyalinisation - Thickening of GBM and mesangial matrix - Nodular Kimmelstiel-Wilson glomerulosclerosis OR diffuse glomerulosclerosis - Papillary necrosis
58
Progression of Diabetic nephropathy (4 stages)
1. Elevated GFR (transient, early on) 2. Glomerular hyperfiltration due to increased mesangial matrix 3. Microalbuminuria (GFR normal) 4. Macroalbuminuria = overt nephropathy (GFR decr, proteinuria incr)
59
Pathophysiology of membranous nephropathy
Diffusely thickened GBM Sub epithelial IgG+C3 deposits
60
Hereditary disorders of CRD
Adult polycystic kidney disease Familial nephritis Reflux nephropathy with vesicoureteric reflux
61
How does PKD present ? What does renal US show?
Autosomal dominant: - abdo pain +/- haematuria (bleeds into cyst), cyst infection, renal calculi, HTN, progressive renal failure Recessive often presents in infancy with multiple renal cysts and congenital hepatic fibrosis Renal U/S: kidneys enlarged and full of cysts
62
What other medical conditions are associated with PKD?
Liver cysts Diverticular disease Ovarian cysts Intracranial aneurysm -> SAH
63
At what age do people with PKD typically reach ESRF?
mutation in: - PKD1 (85%): by 50s - PKD2 (15%): by 70s
64
Management of CRF
Identify and treat cause! Control HTN (SBP<130) - ACEi or ARB (second line is CCB) BSL control Fluid balance - loop diuretics - salt and fluid restriction Diet - low protein diet to reduce nitrogenous wastes (urea, uric acid) - restrict K and PO4 Adjust meds (avoid nephrotoxic and renally excreted meds) Manage complications - Vit D and Ca supplements - phosphate binders - Epo +/- Iron - sodium bicarbonate - statin Dialysis when GFR <15ml/min or uraemic SX onset
65
What are the different types of dialysis and what are the main concepts of each?
Haemodialysis: - blood circulates at high volume through a dialysed composed of many tubes of semi-permeable membranes - solutes move by osmosis - fluid moves by ultrafiltration Peritoneal dialysis - dialysis solution infused into peritoneal cavity, left to dwell for equibrilation of solutes and fluids, then the used dialysate is discarded - semi permeable membrane is the visceral capillary wall lining the peritoneal cavity - solutes leave blood via diffusion - fluids leave blood by mix of osmotic and hydrostatic pressure
66
Complications of renal transplant
- Graft rejection - surgical complications - drug toxicity - infection (opportunistic due to long-term immunosuppression) - malignancy 5x increased risk - CV disease
67
Absolute CI to renal transplant surgery
Cancer Active infection Severe comorbidity
68
What is the leading cause od death amongst CKD patients?
CVD
69
What is hypertensive nephrosclerosis? What does it feature? How can it present?
Damage to kidney resulting from chronic high BP Features renal hyaline arteriolosclerosis -> narrows arteriole lumina -> ischaemia -> tubular atrophy, interstitial fibrosis and glomerulosclerosis Presents in hypertensive patient as mild proteinuria OR haematuria and proteinuria
70
Risk factors for renal stones
``` White male High protein, salt, Ca intake dehydration Metabolic abnormalities (can be hereditary) Urinary tract abnormalities Medication (loop diuretics) ```
71
Clinical presentation of renal stones
Asymptomatic Acute severe flank pain or waxing and waning severe loin to groin pain Haematuria (90% microscopic) Nausea, vomiting +/- Frequency, urgency (LUTS from bladder stones) Fever, hypotension, tachycardia and tachypnoea
72
Types of bladder stones and their treatment. radio-opaque or lucent on KUB?
Analgesia and fluids for all +/- antiemetics Calcium (75%) - incr fluid +/- thiazides, Ca channel blockers or alpha blockers to promote stone passage - radiopaque on KUB ``` Uric acid (5-10%) - incr fluid intake and alkalinise urine +/- allopurinol - radiolucent on KUB ``` Struvite (5-10%) - often harbour bacteria, needs removal and ABx Cysteine (1%) - incr fluid intake and alkalinise urine
73
What is the order of investigations for suspected renal stones?
1. Non-contrast helical CT of abdo/pelvis is first line! If CT shows stone: 2. KUB X-ray (for follow up) - intervention required if solitary kidney/bilateral stones/ARF/intractible pain OR low likelihood of stone passage. If recurrent Ca stone formation, investigate for metabolic causes - 2x 24 hour urine - PTH - Cr - Ca, Na, Ph, Mg - Oxalate, citrate, cysteine
74
Risk factors for RCC
Smoking, HTN, obesity Male and >50 Haemodialysis (15%)
75
Where does RCC metastasise to?
Lungs first -> cough -> CXR -> cannon ball mets Bone -> bony pain Liver 25% at presentation have metastatic disease
76
Paraneoplastic syndromes (SX of cancer not explained by its anatomical position)
PUO/flu-like illness Hematopoietic: - anaemia - polycythemia - raised ESR Endocrinopathies - hypercalcaemia - incr epo - incr renin -> HTN - incr prolactin, gonadotropins, TSH, insulin, cortisol Hepatic cell dysfunction w abdominal LFTs and reversible areas of hepatic necrosis
77
How does RCC present?
1. Commonly asymptomatic - detected incidentally by U/S or CT 2. Loin pain/ flank pain gross haematuria palpable mass 3. Weight loss, weakness, bone pain, anaemia
78
Treatment for RCC
Systemic therapy (immunotherapies and chemo) doesn't work! Surgery the only curative treatment -> remove the kidney (or partial nephrectomy if bilateral tumour or only one remaining kidney) and solitary mets + targeted therapies (T kinase, MTOR, anti-VEGF inhibitors) for advanced stage disease + pal care
79
Differentials for haematuria
Urothelial malignancy - TCC (bladder) - RCC (kidney) - Prostate ``` UTI, cystitis, pyelonephritis BPH Stones Trauma (surgery or blunt trauma) PCKD/simple renal cyst GN or IN Systemic disease - SLE, autoimmune ```
80
Investigations for haematuria
Dipstick - nitrates, WCC, protein, microscopic haematuria (nephrological) Urine MCS (cytology for cancer cells) FBE - anaemia, WCC UEC Imaging: U/S first line +/- IVU (CT + contrast) + CYTOSCOPY (unless <40)
81
What is the most common form of carcinoma of the renal pelvis and ureter? What are clinical features?
Papillary urothelial carcinoma Gross/microscopic hematuria Flank pain LUTS Flank mass +/- hydronephrosis Investigate w IVU + cystoscopy and retrograde pyelogram
82
Risk factors for bladder common
``` Smoking Aromatic amines Cyclophosphamide Pelvic Radiation Chronic irritation: cystitis, chronic catheterisation, bladder stones ```
83
What are the 2 most common forms of bladder cancer?
TCC >90% | SCC 5-7%
84
Clinical features of bladder cancer
HAEMATURIA!! Painless (50%) or painful (50%) Cystitis like symptoms with no infection on urine test (storage LUTS) Advanced disease: bony pain, ureteric obstruction
85
Treatment for bladder cancer
Depends on stage Superficial (non-muscle invasive): - TURBT + adjuvant intravesical therapy (6 week course of BCG or mitomycin C to decrease recurrence) - cystectomy with high grade disease or non-responders Invasive disease - radical cystoprostatectomy + neoadjuvant chemo-radiotherapy
86
Investigations for RCC
U/A, Urine MCS and urine cytology U/S bladder IVP (filling defect) Cystoscopy with bladder washings *GOLD STANDARD* Biopsy - establish diagnosis and determine staging Bladder tumour markers CT/MRI, CXR, LFTs etc for invasive disease
87
Investigations for prostate cancer
DRE and PSA TRUS-guided needle biopsy Bone scan if PSA >10 CT scan (mets?)
88
What scoring system is used to assess mortality risk of prostate cancer?
``` Gleason score! Scale of 10 - GRADE the 2 most common histological patterns on a scale 1-5 on biopsy and add the scores to get the gleason score <7 low risk 7 moderate risk 8-9: high risk ```
89
Treatment options for prostate cancer
``` Prostatectomy Hormone therapy (androgen deprivation therapy) ```
90
Side effects of androgen deprivation thearpy
Hot flushes loss of libido, impotence tiredness, loss of muscle, osteoporosis cognitive dysfunction
91
Why is prostate cancer screening poor?
We are over diagnosing low grade and under diagnosing aggressive high grade cancers. Due to lead time and lag time bias. □ Likelihood of getting aggressive fast growing cacner whilst it is curable and screenable is very low. These men are missed with screening, and these are the people that need treatment most. Vs much higher likelihood with slow growing cancers because the window of time that it is curable and screenable is much longer. But these are the men that would do well anyway.
92
Treatment of Prostate cancer
○ Watchful waiting - no treatment or monitoring § Wait for symptomatic disease and then paliate ○ Active surveillance - monitor tumour for signs of growth or symptoms to appear § Serial PSA, DRE, repeat biopsies § Goal is to avoid overtreatment and side-effects § Radical prostatectomy (high-risk disease or young patients) § Radiation therapy (brachytherapy etc) - for low volume, low grade cancer § Chemotherapy § Hormonal therapy (anti androgens, GnRH agonists, oestrogens, bilateral orchidectomy removes 90% of testosterone )
93
When to start screening for prostate cancer?
All men at age 50 + if >10 year life expectancy. Initial screening involves serum PSA and DRE High risk individuals at age 40
94
Clinical presentation of urinary retention What presentation is a medical emergency?
``` Poor urinary stream w intermittent flow Strain Sense of incomplete voiding Hesitancy Incontinence, nocturia, frequency ``` ANURIA and suprapubic, dull constant pain is a medical emergency!
95
Investigations for suspected urinary retention
U/S bladder PSA (raised in prostate cancer, BPH and prostatitis) CT MRI if cauda equine syndrome suspected
96
Causes of urinary retention
Bladder - trauma - scarring of bladder neck (iatrogenic causes) - neurogenic bladde (splanchnic nerve damage or cauda equina syndrome) - detrusor sphincter dyssynergia Prostate - BPH - Prostate cancer - Prostatitis Penile urethra - congenital - phimosis or pinhole meatus - circumcision - obstruction - Gonorrhoea, chlaymadia Other - drugs - psychogenic
97
Treatment of urinary retention
URinary catheter to empty bladder OR suprapubic puncture if can't catheterise + Alpha blockers and TOV Acute surgery - Prostatic stent, TURP, laser, open prostatectomy etc Treat the underlying cause (BPH etc) bladder outlet surgery
98
Complications of urinary retention
Acute - bladder rupture - hydronephrosis and pyonephorisis leading to ARF - Sepsis Chronic - bladder damage - CKF - bladder stones - hydronephrosis - diverticula in bladder wall -> stones, infection
99
LUTS
Voiding SX - hesitancy - slow or intermittent stream - incomplete emptying - terminal dribbling Storage SX - frequency - urgency - nocturia - incontinence
100
Aetiology of problems with 'waterworks' in males
Obstructive - BPH or prostate cancer - stricture Irritative - secondary to obstruction - UTI - Bladder cancer - stone - diabetes - TB - medical causes (diuretics, anticholinergics); caffeine and alcohol etc
101
Treatment of BPH
Alpha blockers (relaxes smooth muscle of urethra) +/- 5 alpha reductase inhibitors (blocks conversion of testosterone to DHT) reduces prostate volume. Surgical - TURP - open prostatectomy
102
What type of bladder retention is painful and which is more dangerous? Which is associated with bed wetting?
Acute retention for both pain and dangerousness. Chronic assoc w bed wetting due to overflow. Not painful.
103
Causes of acute bladder retention
BPH, prostate cancer, stricture Weak detrusor muscle due to old age ``` Acute precipitants: - UTI (urethritis) - diuresis (alcohol) - drugs (anticholinergic) - post-op - prolapse in women Neurological - DM - Stroke - PD - spinal cord compression ```
104
How is obstructive nephropathy defined?
Elevated Creatinine Bilateral hydronephrosis Due to significant back pressure from bladder (AUR) causing renal dysfunction MX: admit, monitor urine output and U&Es regularly and replace urine output with normal saline + electrolytes as needed.