Genitourinary: Part 2 Flashcards
Define Aute Kidney Injury
- An abrupt sustained rise in serum urea and creatinine due to rapid decline in GFR causing failure to maintain fluid, electrolyte and acid-base homeostasis -usually but not always reversible or self-limiting
Define CKD
Long-standing and progressive impairment in renal function
What is the RIFLE classification of AKI
Describe three levels of renal dysfunction and two outcome measures (products increasing degree of renal damage and have a predictive value for mortality)
Risk Injury Failure Loss End-stage renal disease
What is the current staging system for AKI
Creatinine:
- Increase in 26 micro mol/L in 48Hr
- Increase in 2-2.9 x baseline
- Increase in 3 x baseline
Urine output:
Less than 0.5mL/Kg/h for > 6 consecutive hours
What condition is usually associated with AKI
Sepsis
What defines severe AKI
Creatinine greater than 500 micro mol/L
Symptoms of AKI
- Diarrhoea
- Haematuria
- Haemoptysis
- Hypotension
- Urine retention
Most common causes of AKI
- Ischaemia
- Sepsis
- Nephrotoxins
Pre-renal causes of AKI
- Renal hypo perfusion (hypotension drop in GFR)
- Hypovolaemia
- Hypotension without hypovolaemia - cirrhosis or septic shock
- Low CO 0 cardiac failure or cariogenic shock
- Renal hypoperfusio nay NSAIDs or ACEI
Intrinsic renal causes for AKI
- Renal parenchyma damage
- Acute tubular necrosis
- Vascular reasons
- Glomerular diseases
- Interstitial diseases
What are vascular causes for instrinc renal AKI
- Renal artery/vein thrombosis
- Cholesterol/thrombus emboli from angiography
- Vasculitis (SLE)
- Haemolytic uraemia syndrome (thrombotic microangiopathy/haemolytic anaemia + reduced platelets)
- Malignant hypertension
What are glomerular causes for AKI
- Glomerulonephritis or nephrotic syndrome
2. Du eto autoimmune (SLE, drugs or infections
Interstitial causes for AKI
- Drugs and infiltration following chemo
Post-renal causes for AKI
- Urinary tract obstruction at ureter, bladder or prostate
- Luminal: stones, clots or sloughed papillae
- Mural:
- Malignancy
- Benign prostate hyperplasia
- Strictures - Extrinsic compression from malignancy especially from pelvis or due to retroperitoneal fibrosis
Risk factors for AKI
- Age> 75 years
- Heart failure
- Peripheral vascular disease
- Chronic liver disease
- Sepsis
- Poor fluid intake/increased losses
- History or urinary symptoms
- Past history of AKI
- GFR <60
- Hpovolaemia
- Haematological malignancy
- Diabetes
- Prostate cancer
- Radioogical contrast use
Clinical presentation of AKI
- Palpable bladder, kidneys(polycystic disease), abdo/pelvic masses and rashes
- Oliguria (small amounts of urination) in early stage
- irregular heartbeats due to hyperaemia
- Symptoms of high urea:
- Fatigue, weakness, anorexia, nausea and vomitinig
- Pruritus and brusing
- Confusion, seizures and coma - Breathlessness rom anaemia and pulmonary oedema secondary to volume overload
- Pericarditis (pericardite rub)
- Postural hypotension
- Oedema
- Thirst - indicated fluid depletion and dehydration
Differential diagnosis of AKI
- Abdo aortic aneurysm
- Alcohol toxicity
- Alcoholic and diabetic ketoacidosis
- Chronic renal failure
- Dehydration
- GI bleed
- Herat failure
Diagnosis of AKI
- Establish if AKI is pre, renal, post
- Urine dipstick
- FBC
- Ultrasound
- CT-KUB
- ECG
- CXR
- Renal biopsy
- mid=stream Blood culture to exclude infection
BIOPSY
FBC results:
- HIGH ESR
- Anaemia
Suggests myeloma and vasculitis as underlying cause
- High phosphate
- Low Ca
- High creatinine
When do we suspect CKF
Small kidneys on ultrasound Anaemia Low ca High phosphate ugh creatinine/low GFR
Urine dipstick results for CKD
- leucocyte and nitrile presence - Infection
2. Glomerular disease (blood and proteins)
Ultrasound results for CKD
- Give assessment on renal size
- Distinguish obstruction and hydronephrosis and look of abnormal cysts and masses
Corticomedullary differentiation
What would a CT-KUB show
- Obstructive cause
What usually causes urinary obstruction in males
- Elderly men usually Benign prostatic hyperplasia
What relives benign prostatic hyperplasia
Cathetisation
What should we do if cauterisation does not improve urinary obstruction
Suspect obstruction above prostate:
Urgent ultrasound to look for hydronephrosis
Urgent CT-KUB for obstructing masses/calculi or retroperitoneal fibrosis
Role of ECG in reCKD
- Hyperkalaemic hcnages
Role of CXR in CKD
Look for pulmonary oedema
When ar biopsies done
Interregnal causes for AKI
Done for unexplained AKI and normal kidneys
How is CKD treated pre-renally
- Correct volume depletion with fluids
2. Sepsis = antibiotics
How is CKD treated intrinsic renal
Refer to nephrology over tubulointerstitial or glomerular pathology
How is CKD treated post-penally
- Catheterise and consider CT or renal tract
2. Obstruction or hydronephrosis - cytoscopyy, retrograde stents or nephrostomy insertion - buys time for treatment
How is CKD treated for all causes
- STOP NEPHROTOXIC DRUGS
- Optimise fluid balance
- Hyperkalaemia:
CALCIUM GLUCONATE - cardioprotective
INSULIN + glucose to drive K into cells
Use dialysis or haemofiltration - Treat acidosis with sodium bicarbonate
- Treat pulmonary oedema with diuretics FUROSEMIDE or dialysis
- Renal replacement therapy
Name some nephrotoxic drugs
1> NSAIDS
- ACEI
- GENTAMYCIN
- AMPHOTERICIN
Diet to treat CKD
- NA / K restriction
2. Supply Vit D
What are indications for dialysis
- Symptomatic uraemia including pericarditis or tamponade
- Hyperkalaemia not controlled by conservative measures
- Pulmonary oedema
- Severe acids
- High K
- tall T waves, low flat p waves, broad QRS or arrhythmias on ECG
- Metabolic acidosis
- Fluid overload that is resistant to diuretics
Most common RRT
Haemofiltrtaion
Haemodialysis
Complications of RRT
- Cardiovascular disease (MI) due to hypertension or calcium/phosphate dysregulation
- Infection
- Amyloid accumulate sin long-term dialysis can cause carpal tunnel syndrome, arthralgia and fractures
- Malignancy is commoner in dialysis patients - may be due to cause of end-stage renal failure
Define glomerulonephritis
Broad term that refers to a group of parenchymal kidney diseases that all result in the inflammation of the glomeruli and nephrons
What is the consequence of glomerulonephritis
End stage renal failure
How does glomerulonephritis effect the body
- HAEMATURIA and PROTEINURIA
- Damage to glomerulus restricts blood flow = compensatory HYPERTENSION
- AKI due to loss of filtration capacity
In what four ways can glomerulonephritis present
1, Acute Nephritic Syndrome (Acute glomerulonephritis)
- Nephrotic syndrome
- Asymptomatic urinary abnormalities - haematuria, proteinuria or both
- CKD
What causes acute nephritic syndrome
Immune response triggered by an infection
What characterises Acute Nephritic Syndrome
- Haematuria - visible or non-visible (red cell casts seen on microscopy)
- Proteinuria (usually <2g in 24 hours)
- Hypertension and oedema (periorbital, leg or sacral)
What is the most common primary cause of acute glomerulonephritis
IgA neuropathy
How does IgA neuropathy cause acute glomerulonephritis
It accumulates in the glomeruli causing inflammation
What bacterial infections can cause Acute glomerulonephritis
MRSA, typhoid or secondary syphilis
What viruses can cause acute glomerulonephritis
Hep B and C
What worm can cause acute glomerulonephritis
Schistomiasis
How does Strep. pyogenes cause Acute Glomerulonephritis
- Occurs in a child 1-3 weeks after streptococcal infection (pharyngitis or cellulitis) with a Lancefield group A beta-haemolytic streptococcus
When does strep. pyogenes occur
2 weeks after tonsillitis
How does strep. progenies cause acute glomerulonephritis
Bacterial antigen becomes trapped in the glomerulus leading to an act diffuse proliferative glomerulonephritis
How is acute glomerulonephritis
- Antibiotics
2. Supportive
What conditions can cause acute glomerulonephritis
- Infective endocarditis
- SLE
- Systemic Sclerosis
- ANCA associated vasculitis
- Goodpastures disease
- IgA neuropathy
Treatment of SLE
Immunosuppression: Cyclophosphamide
Rituximab
How is systemic sclerosis diagnosed
ANA positive, Anti-ro and Anti-la positive
Severe hypertension
Onion skin changes on renal biopsy
What is ANCA associated vasculitis
- Multisystem small vessel vasculitis attack small vessels in kidney and the eye
How is ANCA associated vasculitis treated
- IMMUNOSUPRESSION
Cyclophosphamide
Rituximab
Plasma exchange
What is good pastures disease
The co-existence of acute glomerulonephritis and pulmonary alveolar haemorrhage and the presence of circulating antibodies directed against an intrinsic antigen to the basement membrane of both kidney and lung
Makes antibodies against glomerular basement membrane
How is good pastures disease treated
- Remove antibody via plasma exchange
- Immunosuppression
- Steroids/cyclophosphamide
Most common cause of nephritic syndrome
IgA Nephropathy
Where does IgA deposit in the kidney
Mesangium (provides structural support to glomerulus) of kidneys and kidney get attacked
What condition is IgA nephropathy associated with
Tonsilitis
What treatment is needed for IgA nephropathy
BP control - ACEI, angiotensin receptor blockers
Clinical Presentation of nephritic syndrome
- Haematuria
- Proteinuria (uaully less than 2g in 24 hours)
- Hypertension and oedema due to salt and water retention
- Oliguria (little urine)
- Uraemia and symptoms of it:
- Anorexia
- Pruritus
- Lethargy and nausea - Deteriorating kidney function
- Moderate-severe decrease in GFR
Diagnosis of acute nephritic syndrome
- History
- eGFR, proteinuria, serum urea, electrolytes and albumin
- Culture - swab from throat and infected skin
- Urine dipstick to detect proteinuria and haematuria
- Renal biopsy if necessary
How is Acute nephritic syndrome treated
Hypertension = loop diuretics ORAL FUROSEMIDE)
AMLODIPINE (calcium channel blocker)
What defines nephrotic syndrome
- Proteinuria > 3.5g/24 hours
- Hypoalbuminaemia
- Oedema
Hyperlipidaemia
Why is there hyperlipidaemia in nephrotic syndrome
Liver goes into overdrive due to albumin loss and other protein loss which increases risk of blood clots and produces raised cholesterol
Can you develop kindey failure with nephrotic syndrome
No but HUGE amounts of protein is leaking
What is the most common secondary cause of nephrotic syndrome
Diabetes
Primary cause of nephrotic syndrome
- Minimal change disease in kids
- Membranous neuropathy
- Focal segmental glomerulosclerosis
What is minimal change disease
No deposits or changes to the mesangium yet there is proteinuria and widespread oedema = minimal change
Primary causes membranous neuropathy
Usually IDIOPATHIC
What is membranous neuropathy
Caused by immune complex formation (deposition of IgG and C3) in glomerulus by binding of antibodies to antigens in glomerular basement membrane = triggers a membrane attack complex on glomerular epithelial cells damaging them = leaky
Symptoms of membranous neuropathy
- Asymptomatic preotinuria and microscopic haematuria, hypertension and renal impairment
Secondary causes of membranous neuropathy
- Drugs (NSAIDs)
- Autoimmune (SLE, thyroiditis)
- infection (Hep B or C, schistomiasis)
- Neoplasia (lung, colon,s stomach and breast)
Hows membranous neuropathy treated
IMMUNOSUPPRESION
What is focal segmental glomerulosclerosis
Where scar tissue develops on parts of the glomerulus that filter waste from blood
Pathophysiology of focal segmental glomerulosclerosis
CD80 in podocytes results in increased permeability in glomeruli and thus proteinuria and haematuria
Clinical presentation of focal segmental glomerulosclerosis
- Secondary hypertension and renal impairment
How is focal segmental glomerulosclerosis treated
Corticosteroids and immunosuppressants:
CYCLOPHOSPHAMIDE
CICLOSPORIN
Secondary causes of nephrotic syndrome
- Diabetes
- Amyloidosis
- Infections
- SLE, RA
- GOLD, NSAIDs, ACEI
- Malignancy
Pathophysiology of nephrotic syndrome
Any diseases that cause injury to podocytes will cause loss of foot processes = proteinuria
Clinical presentation of nephrotic syndrome
- Normal-mild increase in BP
- Proteinuria >3.5g/day
- Normal-mild decrease in GFR
- Hypoalbuminaemia
- Pitting oedema of ankles, genital, abdo wall and face (periorbital)
- Frothy urine
Differential diagnosis of nephrotic syndrome
- Congestive heart failure
2. Cirrhosis
Why is nephrotic syndrome misdiagnosed for congestive heart failure
Oedema and raised Jugular venous pressure
Nephrotic = low JVP
How is liver cirrhosis misdiagnosed and distinguished from nephrotic
- Hypoalbuminaemia and oedema
2. JAUNDICE, FEVER
How is nephrotic syndrome diagnosed
- RENAL BIOPSY
- Urine dipstick for proteins
- CXR or ultrasound for pleural effusion or ascites
- Serum albumin low
- BP is increased or normal
- Renal function is normal
FBC results for nephrotic syndrome
- Serum albumin low
- Serum creatinine, eGFR, lipids and glucose
- ANA positive, double-stranded DNA antibody, c3 and c4 = SLE
- Antiphospholipid A2 receptor antibody = membranous nephropathy
Hep B surface antigens
Complications of nephrotic syndrome
- Susceptibility to infection
- Thromboembolism
- Hyperlipidaemia
Why does nephrotic syndrome increase susceptibility to infection
- Low serum IgG, decreased complement activity and T cell function
IgG is being lost in urine and immunosuppressive treatment
Why does nephrotic syndrome cause thromboembolism
- Hypercoaguable state due to increased clotting factors (produced by liver due to low albumin since liver goes into overdrive) and platelet abnormalities
How does nephrotic syndrome cause hyperlipidaemia
- Increased cholesterol and triglycerides due to hepatic lipoprotein synthesis in response to low oncotic pressure due to low albumin
goals of treating nephrotic syndrome
REDUCE OEDEMA
REDUCE PROTEINURIA
REDUCE RISK OF COMPLICATIONS
How do we reduce oedema
- IV FUROSEMIDE (IV as gut prevents absorption)
- IV BENDROFLUMETHIAZIDE
- Fluid and salt restriction
How do we reduce proteinuria
REMPIRIL
CANDESARTAN
Eat normal protein diet
How do we stop microvascular complications
Prophylactic anticoagulation with WARFARIN
SIMVASTATIN
Treat infections and vaccinate