RENAL Flashcards
Define Glomerulonephritis
An IMMUNOLOGICALLY mediated inflammation of the renal glomeruli
Whats the pathophysiology behind glomerulonephritis?
MAINLY: deposition of Ant-Ab complexes in the glomeruli
This leads to inflammation and activation of complement and coagulation cascades
The Ant-Ab complexes either form on the spot in the glomeruli (more common) or are deposited from the circulation
What are common antigents associated with glomerulonephritis?
Bacteria: Streptococcus viridans, Staphylococci
Viruses: HBV, CBV, measles, mumps, EBV.
Protozoa: Plasmodium malariae, Schistosomiasis.
Inflammatory/Systemic Diseases: SLE, vasculitis, cryoglobulinaemia.
Drugs: Gold, Penicillinamine.
Tumours
State the 2 main classes of glomerulonephritis
Non proliferative and proliferative
List the different types of glomerulonephritis
NON-PROLIFERATIVE:
- Minimal-change glomerulonephritis
- Membranous glomerulonephritis
- Focal Segmental glomeruloSCLEROSIS
PROLIFERATIVE:
- IgA nephropathy
- MembranoProliferative GlomeruloNephritis (MPGN)
- Focal segmental proliferative glomerulonephritis
- Diffuse proliferative glom.
- Crescentic glomerulonephritis aka Rapidly progressive glomerulonephritis (vasculitic disorders & goodpastures syndrome)
What are the PC of glom. ?
- Haematuria
- SC oedema
- History of recent infection
- Symptoms of uraemia or renal failure
What are the signs OE for glom.
- Hypertension
- Proteinuria
- Haematuria (especially in IgA nephropathy)
What is the triad of the NEPHROTIC syndrome?
Proteinuria > 3.5 g/24 hrs
Low serum albumin < 24 g/L
Oedema
NOTE: due to the hypoalbuminaema, the liver tries to compensate and hence increases the production of lipids causing hyperlipidaemia!
What is the triad of the NEPHRITIC syndrome?
- Haematuria
- Proteinuria
- Hypertension
Pores in the podocytes are large enough to allow protein AND RBC to pass in the urine.
Red cell casts may also be present - indicating glomerular damage
What are the IX for glom. ?
BLOODS: FBC U&E's - creatinine LFT's - Albumin * Lipid profile Complement studies Antibodies
URINE
Microscopy
24hr collection - to monitor creatinine clearance and protein
IMAGING:
US- of the Renal Tract to exclude (obstruction)
RENAL Bx
for microscopy
Investigations for associated conditions: HBV, HCV, HIV serology.
Which antibodies are you testing for in glom. ?
ANA Anti-dsDNA ANCA Anti-GBM Ab Cryoglobulins
How can you determine the anatomical origin of macroscopic haematuria based on its presentation?
Bladder bleeding = present throughout voiding
Terminal bladder or prostatic bleeding = end of voiding
Urethral bleeding = beggining of voiding.
What are red cell casts and what do they indicate?
Are RBC that have leaked into renal tubules and clump together forming a cast-like structure which is excreted in the urine
They suggest glomerular pathology/damage.
Which is the most common cause of glom.?
IgA nephropathy (Berger's disease) is the most common cause Can present at any age
What is Henoch-Schonlein Purpura?
How does it present?
A small type vasculitides Systemic involvement (compared to Berger's)
It presents with:
Arthritis of large joint
Abdominal pain
Characteristic purpuric rash of the extensor skin surfaces.
“purpura, arthritis, gut symptoms,
glomerulonephritis, IgA deposition”
Is a RF for orchidits and epididymitis
Post op diabetic pt gets delirious and agitated
What are you thinking?
Hyponatraemia due to fluid overload due to excess dextrose solution given post-op which causes dilutional hyponatraemia resulting in acute delirium.
What is diabetic nephropathy?
A chronic progressive disease that arises in diabetic pts
It’s characterised by an initial increase in glomerular filtration rate and glomerular BM hypertrophy.
As the disease progresses glomerulosclerosis occurs as a result of accumulation of ECM and destroying the filtering ability of the glomerular membrane.
This allows proteins leakage.
Severe diabetic nepropathy can present with nephrotic syndrome symptoms.
Acute derangement of biochemistry does not occur though.
What derangment of biochemistry would excess insulin cause?
Hypoglycaemia
Low K+
Due to a shift of K to the IC compartment.
PC: irritable, sweat and can fall into comma.
Tubulointerstitial nephritis
Due to drug hypersensitivity reactions - penicillin, NSAID’s.
PC: fever, skin rash, painful joints
Blood: HIGH eosinophils
Where are eosinophils raised?
Allergic responses like: Asthma Drugs Parasitic infections Tissue inflammation
What is the most appropriate first IX in renal stones?
KUB US or Abdominal US in SBA
of the KUB (Kidneys, Ureters, Bladder)
80% of stones are visible on US
What are the most commons kidney stones?
Calcium oxalate
List the types of kidney stones
o Calcium oxalate - MOST COMMON
o Struvite - quite common
o Urate - 5%
o Cysteine - 2%
Explain the aetiology/risk factors of urinary tract calculi
• Many cases are IDIOPATHIC
Metabolic Causes o Hypercalciuria o Hyperuricaemia o Hypercystinuria o Hyperoxaluria
Infection
o Hyperuricaemia
Drugs
o Indinavir
• RISK FACTORS:
o Low fluid intake
o Structural urinary tract abnormalities (e.g. horseshoe kidney)
What is indinavir?
Indinavir (IDV; trade name Crixivan, manufactured by Merck) is a protease inhibitor used as a component of highly active antiretroviral therapy to treat HIV/AIDS.
RF for kidney stones.
Recognise the presenting symptoms of urinary tract calculi
- Often ASYMPTOMATIC
- SEVERE loin to groin pain
- Nausea and vomiting
- Urinary urgency, frequency or retention
- Haematuria
Recognise the signs of urinary tract calculi on physical examination
- Loin to lower abdominal tenderness
- NO signs of peritonism
- Signs of systemic sepsis if there is an obstruction and infection above the stone
What is the main differential to kidney stones in elderly men?
• Leaking AAA is the main differential to consider in older men
Identify appropriate investigations for urinary tract calculi
• Bloods o FBC - high WCC if infection o U&Es - check renal function o Calcium o Urate o Phosphate
• Urine
o Dipstick - haematuria is common
o MC&S
• X-Ray KUB
o 80% of kidney stones are radio-opaque
• Intravenous Urography (IVU)
o Allows visualisation of the kidneys and ureters
• Ultrasound
o May show hydronephrosis and hydroureter
• Non-enhanced Spiral CT
o Can also be used to image stones
• Isotope Radiography
o Used to assess kidney function
Generate a management plan for ACUTE PRESENTATION of urinary tract calculi
• ACUTE PRESENTATION
o Analgesia
o Bed rest
o Fluid replacement
o Urine collection to try and retrieve any stone that has passed
• NOTE: most stones < 5 mm will pass spontaneously
o An obstructed, infected kidney is an EMERGENCY and should be treated as soon as possible to relieve the obstruction (e.g. by placing a percutaneous
nephrostomy)
What is the mx for the removal of calculi?
• REMOVAL OF CALCULI
o Urethroscopy
• A scope is passed into the bladder and up the ureter to visualise the stone
• It can then be removed by a basket or broken up with a laser If the stone cannot be removed, a JJ stent should be placed to allow urine drainage
o Extracorporeal Shock-Wave Lithotripsy (ESWL)
• Non-invasive
• An electromagnetic shockwave is focused onto the calculus to break it up into smaller fragments that can pass spontaneously
o Percutaneous Nephrolithotomy (PCNL)
• Performed for large, complex stones (e.g. staghorn calculi)
• After making a nephrostomy tract, a nephroscope is inserted, which allows disintegration and removal of stones
• TREATMENT OF CAUSE
o Depends on the cause (e.g. parathyroidectomy if hypercalcaemia due to hyperparathyroidism, allopurinol if hyperuricaemia)
• ADVICE
o Increase oral fluid intake
Identify possible complications of urinary tract calculi
• Of Stones
o Infection (PYELONEPHRITIS)
o Septicaemia
o Urinary retention
• Of Ureteroscopy
o Perforation
o False passage
• Of Lithotripsy
o Pain
o Haematuria
Summarise the prognosis for patients with urinary tract calculi
- GOOD
- However, infection of the calculus could lead to irreversible renal scarring
- Recurrence of about 50% over 5 yrs