Renal Flashcards
1
Q
Name the causes of End-Stage Renal Failure
A
Pyelonephritis
Diabetic nephropathy
Glomerulonephritis
Polycystic Kidney Disease
2
Q
Define Acute Kidney Injury
A
Rapid reduction in kidney function over hours to days, as measured by serum urea and creatinine
Common, occurs in up to 18% of hospital patients
3
Q
What is the NICE criteria for an AKI?
A
Rise in creatinine >25 umol/L in 48 hours
Rise in creatinine of >50% in 7 days
Urine output of <0.5ml/kg/hour for >6 hours
4
Q
What are the risk factors for AKI?
A
Age >75 Chronic kidney disease Heart failure Diabetes Liver disease Drugs (nephrotoxic - NSAIDs, ACE-inhibitors etc...) Sepsis Cognitive impairment Contrast medium - CT scans Poor fluid intake Previous AKI
5
Q
What are the Pre-Renal causes of an AKI?
A
Hypotension (hypovolaemia, sepsis) Renal artery stenosis Heart failure/MI Dehydration Drugs e.g. ACE-inhibitors, NSAIDs GI bleeding Vomiting and diarrhoea
6
Q
What are the Intrinsic causes of an AKI?
A
Acute tubular necrosis (most common)
Glomerulonephritis (SLE, HSP, infections, drugs, anti-GBM disease, ANCA vasculitis)
Interstitial nephritis (drugs, lymphoma)
Vascular disease (thrombosis, HUS/TTP, scleroderma)
Rhabdomyolysis
Radiocontrast
7
Q
What are the Post-Renal causes of an AKI?
A
Kidney stones
Malignancy (ureteric, bladder, prostate)
Ureter or urethral strictures
Enlarged prostate or prostate cancer (BPH) (high PSA)
8
Q
What are the nephrotoxic drugs?
A
CANT DAMAG
Contrast ACE-inhibitors NSAIDs Therapeutic index (narrow) Diuretics Antibiotics (Penicillin, cephalosporin) Metformin ARB Gentamicin/gold
9
Q
Why are changes in creatinine assessed and not total amount when calculating AKI staging?
A
Because the total amount is affected by muscle mass, gender, age and ethnicity. Will be higher in those with a larger muscle mass etc.
10
Q
What is stage 1 on the KDIGO staging system?
A
Creatinine increase 1.5-1.9 x baseline
Urine output <0.5 mL/kg/hour for >6 hours
11
Q
What is stage 2 on the KDIGO staging system?
A
Creatinine increase 2.0-2.9 x baseline
Urine output <0.5 mL/kg/hour for >12 hours
12
Q
What is stage 3 on the KDIGO staging system?
A
Creatinine increase >3 x baseline OR >354umol/L
Urine output <0.3 mL/kg/hour for >24 hours OR anuria for 12 hours
13
Q
What the symptoms of AKI
A
Decreased urine Vomiting Dizziness (orthostatic suggests pre-renal) Orthopnoea (fluid overload) Altered mental state Signs of uraemia Peripheral oedema Hyper/hypotension Muscle tenderness (rhabdomyolysis) Ascites
14
Q
Investigations in an AKI
A
U&E’s - elevated creatinine, high serum potassium (most important) -> hyperkalaemia >5.5, metabolic acidosis
Urinalysis - leucocytes & nitrites = infection, proteinuria and haematuria = glomerular disease (Acute nephritis), glucose = diabetes
FBC - Anaemia (CKD, blood loss), thrombocytopenia (HUS, TTP)
Imaging - Renal/urinary tract USS (KUB) -> obstruction, cysts, mass
ECG -> hyperkalaemic signs = tall tented T waves, absent P waves, broad QRS complex, sinusoidal
15
Q
Management for an AKI
A
Stop nephrotoxic drugs - NSAIDs. ACE-inhibitors
Fluid rehydration with IV fluids in pre-renal
CTKUB for obstruction
Uraemic/acidaemia => dialysis
Treat hyperkalaemia -> Insulin + glucose, calcium gluconate
Odema = Oxygen, CPAP, Diamorphine, furosemide
16
Q
Complications of an AKI
A
Hyperkalaemia
Pulmonary oedema
Metabolic acidosis
Uraemia (high urea) -> can lead to encephalopathy/pericarditis
17
Q
Define Chronic Kidney Disease
A
Impaired renal function for >3 months based on abnormal structure or function (proteinuria or haematuria), or GFR <60 ml/min/1.73m/m for >3 months with or without evidence of kidney damage
18
Q
Causes of CKD
A
Diabetes - 40% Hypertension Glomerulonephritis (IgA nephropathy, FSG, lupus, amyloidosis) Polycystic kidney disease Mediciations - lithium, PPI's, NSAID's Pyelonephritis
19
Q
What is the clinical exam picture of a patient with CKD?
A
Hypertensive diabetic over the age of 50
20
Q
Risk factors for CKD
A
Old age Hypertension Smoking Obesity Diabetes Medications
21
Q
Symptoms for CKD
A
Usually asymptomatic Nausea and vomiting Fatigue (anaemia - lack of EPO) Muscle cramps Anorexia Pruritus (itching) Oedema (salt and water retention) Bone pain Pallor
22
Q
Stages of CKD
A
Stage 1 = GFR >90 with evidence of kidney damage
Stage 2 = GFR 60-89 with evidence of kidney damage
Stage 3a = GFR 45-59 with or without kidney damage
Stage 3b = GFR 30-44 with or without kidney damage
Stage 4 = GFR 15-29 with or without kidney damage
Stage 5 = GFR <15 - End-Stage Renal Failure
23
Q
Investigations for CKD
A
Urinalysis - haematuria, proteinuria, leucocytes or nitrites = infection
U&E’s - eGFR - two tests 3 months apart, serum creatinine is elevated
FBC - normochromic, normocytic anaemia
Glucose
Renal USS -> small kidney <9cm = obstruction, large kidney = amyloidosis, myeloma
Renal biopsy - if unexplained CKD
24
Q
Name the complications of CKD
A
Anaemia Renal bone disease (CKD-mineral and bone disorder) CV disease Peripheral neuropathy Hyperkalaemia Dialysis related problems Pulomonary oedema Metabolic acidosis Protein malnutrition
25
Explain the pathophysiology behind anaemia in CKD
Anaemia is as a result of EPO deficiency (also blood loss, ACE-inhibitors, chronic disease). EPO stimulates RBC production
Treatment: Erythropoeitin
26
Explain the pathophysiology behind CKD mineral and bone disorder
Vitamin D deficiency causes low Calcium (hypocalcaemia) which causes PTH elevation (hyperparathyroidism)
Results in osteoporosis, osteomalacia, osteosclerosis
Treatment: Vitamin D (alfacalcidol and calcitriol), Calcium supplements, Bisphosphonates
27
Treatment for CKD
Stop nephrotoxic drugs
Relieve obstruction
Reduce risk of CV disease: stop smoking, lose weight
Glycaemic control
Treat BP -> ACE-inhibitors, ARB, CCB
Manage complications: Anaemia, renal bone disease
Oedema: loop diuretics (furosemide) + fluid restriction
Dialysis and renal transplant in end stage renal failure
28
Define nephritic syndrome including symptoms
Refers to a group of symptoms, not a diagnosis
Haematuria
Oliguria (reduced urine output)
Fluid retention
Proliferative
29
What are the causes of nephritic syndrome?
IgA nephropathy
Post-streptococcal
Rapidly progressive GN
SLE
30
Define IgA nephropathy
Most common cause of primary glomerulonephritis
Peak is 20 years old
Visible haematuria
Renal biopsy - IgA deposits and mesangial proliferation
Treatment: ACE-inhibitors or immunosuppression (steroids)
31
Define post-streptococcal nephritic syndrome
Occurs 1-12 weeks after a sore throat (tonsilitis)
Causative organism = Strep pyogenes
Supportive treatment -> resolves over 2-4 weeks
32
Define rapidly progressive GN
Histology shows crescentic glomerulonephritis
Fever, myalgia, weight loss
Goodpasture's syndrome: Kidney failure + haemoptysis. Anti-GBM antibodies. Treatment = High dose IV steroids, cyclophosphamide, plasma exchange.
Wegener's granulomatosis - c-ANCA
Microscopic polyangiitis - p-ANCA
33
Define SLE related to glomerulonephritis
More common in African's
Vascular, glomerular and tubulointerstitial damage
Class I-IV (increasing severity), class V (membranous)
Anti DS DNA/ANA antibodies
Treatment: IV methylprednisolone + cyclophosphamide
34
What is the triad of nephrotic syndrome?
Oedema
Proteinuria (>3.5g/24 hours)
Hypoalbuminaemia
(Hyperlipidaemia as a fourth)
35
Causes of nephrotic syndrome?
Minimal change disease
Focal segmental glomerulosclerosis
Membranous nephropathy
Mesangiocapillary GN
```
Diabetic nephropathy
Hepatitis B/C
SLE
Amyloidosis
Drugs (NSAIDs, gold, penicillamine, anti-TNF)
```
36
Complications of nephrotic syndrome
```
Susceptibility to infections
DVT/PE
Hyperlipidaemia (Cholesterol >10mmol/L)
AKI
Hypertension
```
37
Define minimal change disease
Commonest cause of nephrotic syndrome in children
Caused by: NSAIDs, Hodgkin's lymphoma
Abnormal podocytes - under electron microscope
Treatment: Prednisolone
38
Define focal segmental glomerulosclerosis
Most common in adults
Focal scars on glomeruli
Idiopathic causes or secondary to HIV
Responds to corticosteroids in 30%
39
Define membranous nephropathy
Autoimmune
Can be associated with malignancy, NSAID's, RA
Thickened glomerular basement membrane
Spike and dome appearance
40
Investigations for glomerulonephritis
```
Renal biopsy
FBC's
U&E's
ESR
Urinalysis
ANCA
Hep B/C/HIV
Anti-DSDNA
```
41
Treatment for glomerulonephritis
Reduce oedema -> loop diuretics (furosemide)
Diet - fluid and salt restriction
Reduce proteinuria -> ACE-inhibitors/ARB to control BP
Treat complications: Statins for hyperlipidaemia, anticoagulation for thrombosis (DVT/PE)
Stop causative drugs
42
Define polycystic kidney disease
Genetic condition where the kidneys develop multiple fluid filled cysts
Commonest inherited disease causing ESRF
```
Two types: Autosomal dominant (ADPKD) - more common
Autosomal recessive (ARPKD)
```
43
What genes are affected in autosomal dominant PKD
PKD-1 chromosome 16 (85%) - reach ESRF in 50s
| PKD-2 chromosome 4 (15%) - slower reach ESRF in 70s
44
Signs of ADPKD
```
Renal enlargement with cysts
Abdominal pain + haematuria (haemorrhage into a cyst)
Cyst infection
Renal calculi
Hypertension
Progressive renal failure
CV disease (hypertension)
Palpable, enlarged kidneys
```
45
Extra-renal manifestations of ADPKD
Cerebral aneurysms -> SAH: headaches
Hepatic, splenic, pancreatic, ovarian and prostate cysts
Cardiac valve disease (mitral regurgitation)
Colonic diverticula
Aortic root dilatation
46
What gene is affected in autosomal recessive PKD
Gene on chromosome 6
47
How does ARPKD present?
Enlarged kidneys, renal cysts and congenital hepatic fibrosis
Usually ESRF before adulthood
48
Investigations for PKD
```
Genetic testing - PKD1 or PKD2
Renal USS - Age 18-39 = >3 unilateral or bilateral cysts
Age 40-59 >2 cysts in each kidney
Age >60 >4 cysts in each kidney
U&E's - creatinine
Screen for SAH - MR angiography
Urinalysis - protein, bacteria
ECG - LVH
Echo - aortic root dilatation
```
49
Management for PKD
Hypertension = ACE-i/ARB/CCB
ESRD = Dialysis/renal transplant
Renal stones = analgesia
Infection = Antibiotics e.g. ciprofloxacin
Tolvaptan (vasopressin receptor antagonist) -> slows development of cysts
50
Define Alport syndrome
2nd most common inherited cause of kidney failure
Most commonly X-linked dominant
Affects young males
Mutations in COL4A5 gene - mutation in basement membrane collagen (type IV collagen)
51
Signs of Alport syndrome
Haematuria
Proteinuria
Renal failure
Deafness
52
Treatment for Alport syndrome
Possibly ACE-inhibitors
53
Define the stages of diabetic nephropathy
GFR increases
Glomerular hyperfiltration
Microalbuminuria
Nephropathy -> proteinuria increase
54
What lesions do you see in diabetic nephropathy?
Kimmelstiel-Wilson lesions -> nodular glomerulosclerosis
55
Treatment for diabetic nephropathy
ACE-inhibitors/ARB - to reduce intra-glomerular pressure and proteinuria/treat blood pressure
56
Define renal tubular acidosis
Is metabolic acidosis due to impaired acid secretion by the kidney
There is hyperchloraemic, metabolic acidosis + normal anion gap
57
Define type 1 renal tubular acidosis
Distal tubule pathology
| Distal tubule unable to excrete hydrogen ions
58
Causes of type 1 renal tubular acidosis
```
Genetic
SLE
Sjogren's syndrome
Marfan's syndrome
Sickle cell
Hyperthyroidism
```
59
Symptoms of type 1 renal tubular acidosis
Failure to thrive in children/rickets
Osteomalacia
Renal calculi
60
Investigations for type 1 renal tubular acidosis
Urine pH >5.5
Metabolic acidosis
Hypokalaemia
61
Treatment for type 1 renal tubular acidosis
Oral sodium bicarbonate
62
Define type 2 renal tubular acidosis
Proximal tubule pathology
Inability of the proximal tubule to reabsorb bicarbonate from the urine. Results in excess bicarbonate in the urine -> metabolic acidosis
63
Causes of type 2 renal tubular acidosis
Fanconi's syndrome
Drugs (lead, acetazolamide)
Interstitial nephritis/myeloma
64
Investigations for type 2 renal tubular acidosis
Hypokalaemia
| High excretion of bicarbonate
65
Treatment for type 2 renal tubular acidosis
Oral bicarbonate
66
Define type 4 renal tubular acidosis
Most common cause of renal tubular acidosis
| Reduced aldosterone secretion -> hyperkalaemia
67
Causes of type 4 renal tubular acidosis
```
Addison's disease
Diabetic nephropathy
SLE
HIV
Drugs: ACE-inhibitors, spironolactone, NSAIDs, ciclosporin, beta-blockers
```
68
Investigations for type 4 renal tubular acidosis
Hyperkalaemia
High chloride
Metabolic acidosis
Low urinary pH <5.5
69
Treatment for type 4 renal tubular acidosis
Fludrocortisone - replaces aldosterone
| Hyperkalaemia treatment = Calcium resonium, furosemide
70
Define type 3 renal tubular acidosis
Combination of type 1 and 2
| Pathology in the proximal and distal tubule
71
Define Fanconi syndrome
Proximal tubular dysfunction leading to loss of amino acids, glucose, phosphate and bicarbonate in urine.
72
Complications of Fanconi syndrome
Dehydration
Metabolic acidosis
Oesteomalacia/rickets
Electrolyte abnormalities
73
Causes of Fanconi syndrome
```
Wilson's disease
Lead
Mercury
Gentamicin
Cisplatin
Myeloma
Amyloidosis
```
74
Treatment for Fanconi syndrome
Sodium bicarbonate
| Potassium, phosphate, vitamin D supplements
75
Define pyelonephritis
Infection/inflammatory disease of renal parenchyma, calyces and pelvis that may be acute, recurrent or chronic
76
Causes of pyelonephritis
E.coli (ascending infection from lower urinary tract or due to bloodstream spread of infection (sepsis))
In diabetes -> klebsiella/candida
In HIV/Malignancy/transplant -> candida
77
Risk factors for pyelonephritis
Infants and old age
Structural abnormalities - PKD, horseshoe kidney, VUR
Foreign body - stone, catheterisation
Impaired renal function
Immunocompromised - DM, transplant, malignancy, radio/chemotherapy, HIV
Pregnancy
Obstruction - BPH, stone, bladder neck obstruction, foreign body
78
Symptoms of pyelonephritis
Loin pain
Fever/rigors
Renal tenderness
Vomiting/nausea
79
Investigations for pyelonephritis
```
MC&S of midstream urine
Urine dipstick - blood, protein, nitrites, leukocytes
Urinalysis
Gram stains
FBC
ESR/CRP raised
Blood cultures - sepsis
Renal USS - stones, abscess
Contrast CT
DMSA - renal scarring
```
80
Treatment for pyelonephritis
```
Mild/moderate = ciprofloxacin or cefixime
Severe = Admit to hospital
IV ceftriaxone or IV ciprofloxacin
IV fluids
IV paracetamol (pain and fever)
Catheterisation
```
81
Complications of pyelonephritis
Renal failure
Abscess formation
Parenchymal renal scarring
Recurrent UTI's
82
Define renal cell carcinoma
Renal malignancy arising from proximal renal tubular epithelium
It accounts for 85% of renal cancer
83
Types of renal cell carcinomas
```
Clear cell (80%) - due to cholesterol and glycogen
Papillary tumour (15%)
```
84
Risk factors for renal cell carcinoma
Smoking
Middle aged man - 55 years old
Renal transplant and dialysis
Von Hippel-Lindau syndrome
85
Symptoms of renal cell carcinoma
Classic triad = Haematuria
Loin pain
Abdominal mass
Anorexia
Malaise
Weight loss
Left sided varicocele (due to left testicular vein compression)
Stauffer's syndrome = cholestasis/hepatosplenomegaly
86
Investigations for renal cell carcinoma
```
FBC - polycythaemia from EPO secretion
Creatinine - elevated
Urinalysis - haematuria +/- proteinuria
LFTs - raised ALT/AST
Abdominal/pelvis USS = cysts, mass, metastases
CT abdo/pelvis
MRI
Chest X-ray
```
87
Treatment for renal cell carcinoma
Radical nephrectomy (partial for T1, laparoscopic for T2)
Radio and chemo resistant
Sunitinib, bevacizumab, sorafenib - tyrosine kinase inhibitors
88
Staging for renal cell carcinoma
```
T1 = Confined to kidney <7cm
T2 = Confined to kidney >7cm
T3 = To major veins or adrenals (e.g. vena cava)
T4 = Beyond gerota fascia
LNs = para-aortic and hilar
```
89
Define Wilm's tumour (nephroblastoma)
Childhood tumour of primitive renal tubules and mesenchymal cells. (commonest in children)
90
Symptoms of Wilm's tumour
Abdominal mass
| Haematuria
91
Define interstitial nephritis
Inflammation of the space between cells and tubules (the interstitium)
92
What does acute interstitial nephritis present with?
AKI and hypertension
93
Causes of acute interstitial nephritis
```
NSAIDs
Antibiotics
Infection - staphs/streps
Autoimmune - SLE, sarcoidosis
Diuretics
Allopurinol
Omeprazole
```
94
Symptoms of acute interstitial nephritis
Mild renal impairment
Rash
Fever
Eosinophilia
95
Treatment for acute interstitial nephritis
Stop underlying cause
| Prednisolone -> reduces inflammation
96
What does chronic interstitial nephritis present with?
CKD
97
Causes of chronic interstitial nephritis
```
Analgesic nephropathy
Autoimmune - RA, SLE, Sjogren's
Myeloma
Sickle cell
Drugs
```
98
Treatment for chronic interstitial nephritis
Manage underlying cause
| Steroids
99
Define acute tubular necrosis
Damage and death (necrosis) of the epithelial cells of the renal tubules -> epithelial cells have ability to regenerate, takes 7-21 days.
Most common cause of AKI
100
Causes of acute tubular necrosis
Shock
Sepsis
Dehydration
Radiology contrast dye
Gentamicin
NSAIDs
Lithium
Heroin
101
Investigations for acute tubular necrosis
Urinalysis - "muddy brown casts"
102
Treatment for acute tubular necrosis
IV fluids
Stops nephrotoxic medications
Treat complications
103
Define haemolytic uraemic syndrome (HUS)
Medical emergency
Occurs when there is thrombosis in small blood vessels
Triggered by a bacterial toxin called shiga toxin -> caused by e.coli 0157 and shigella
104
Symptoms of haemolytic uraemic syndrome
```
Anorexia
Diarrhoea
Abdominal pain
AKI
Haematuria/dark brown urine
Confusion
Hypertension
Bruising
Nausea/vomiting
```
105
Investigations for haemolytic uraemic syndrome
Blood film - decreased platelets (thrombocytopenia)
| Proteinuria/haematuria
106
Treatment for haemolytic uraemic syndrome
Dialysis for AKI
Plasma exchange
Antihypertensives
107
Define rhabdomyolysis
Skeletal muscle tissue breaks down and releases contents into blood.
The muscle cells (myocytes) undergo cell death (apoptosis) and release: Myoglobin (toxic to kidney = AKI), Potassium (hyperkalaemia), Phosphate, Creatine kinase
108
Causes of rhabdomyolysis
Prolonged immobility (elderly, frail and falling on the floor)
Rigorous exercise (ultramarathon/triathlon)
Crush injury
Seizures
Alcohol
Statins
Neuroleptic malignant syndrome
109
Symptoms of rhabdomyolysis
```
Muscle aches and pain
Oedema
Fatigue
Red-brown urine
Confusion
```
110
Investigations for rhabdomyolysis
Creatine kinase >1,000-100,000 units/L
Myoglobinuria - myoglobin in the urine "red-brown" colour
U&E's - increased K and PO, decreased Ca, = hyperkalaemia
ECG = hyperkalaemia - tall tented t waves, absent p waves, broad QRS complex, ventricular fibrillation
111
Treatment for rhabdomyolysis
IV fluids for rehydration and filtration
IV sodium bicarbonate to alkalinize urine ph >6.5
IV mannitol
Treat complications: Hyperkalaemia -> insulin and dextrose, IV calcium gluconate
112
What are the indications for dialysis in an AKI patient?
```
Acidosis
Electrolyte abnormalities
Intoxication
Oedema
Uraemia symptoms
```
113
How does haemodialysis work?
Blood is passed over a semi-permeable membrane against dialysis fluid flowing through in the opposite direction.
Blood is always meeting a less-concentrated solution and diffusion of small solutes occurs down the concentration gradient
Regime: Hospital 3x per week (4 hours)
114
Complications of haemodialysis
```
Access - infection, thrombosis, aneurysms, stenosis
Hypotension
Time-consuming
Nausea/vomiting
Headache
Fatigue
```
115
How does peritoneal dialysis work?
The peritoneum is used a semi-permeable membrane. A special dialysis solution containing dextrose is added to the peritoneal cavity. Involves a Tenckhoff catheter used for inserting and removing dialysis solution
Regime: Continuous ambulatory peritoneal dialysis = 4 exchanges of 20 mins. Automated dialysis = occurs overnight.
116
Complication of peritoneal dialysis
```
Bacterial peritonitis
Peritoneal stenosis
Weight gain
Hernia
Hyperglycaemia
```
117
Absolute contraindications for renal transplantation
Active infection
Cancer
Severe comorbidity
118
What needs to be matched for a renal transplant?
ABO blood group
HLA tissue match (A, B, C on chromosome 6)
Antibody screening
119
What drug is used for immunosuppresson induction in renal transplant?
Basiliximab
120
What drugs are used for immunosuppression maintenance in renal transplant?
Triple therapy:
Calcineurin inhibitor (Tacrolimus or ciclosporin)
Antimetabolite (Azathioprine or mycophenolate)
Prednisolone
121
Complications of renal transplant
```
Transplant rejection (hyperacute, acute or chronic)
CV disease (hypertension)
Infection (HSV, CMV)
Malignancy (skin, lymphoma)
Drug toxicity
Delayed graft function
```
