Renal Flashcards
What is glomerulonephritis?
This is inflammation of the glomerulus
What is the difference between primary and secondary glomerulonephritis?
It may be secondary or primary. Primary is where the cause is unknown and secondary is when there is another disease in the body.
What are the kidney cells most likely to be damaged in glomerulophritis?
If podocytes are damaged, there can be a lot of protein in the urine.
If parietal cells are dameged, there will be a crescent shape.
Endothelial cells are usually damaged in systemic disease.
Mesangial cells.
What are some investigations for glomerulonephritis?
A full medical and drug (including recreational) history.
Basics – UEs, dip urine for blood, quantify proteinuria, check albumin, check USS
Glomerulonephritis screen: o ANCA o Anti-GBM o ANA / dsDNA o Complement o Anti-PLA2R o Immunoglobulins o Rheumatoid factor o Virology – hep B, C, HIV
Others: Myeloma screen, HbA1c.
Describe a kidney biopsy is carried out
This is done as a day case. The patient will lie on their tummy and it is ultrasound guided. It is done under local anaesthetic. The patient takes a breath in as the kidneys move when you breath.
It doesn’t matter which kidney is biopsied as both kidney will be affected. However, the left kidney is easier to reach.
The main risk is bleeding as the kidney is a very vascular organ. There is around a 1% chance of a significant bleed.
This is required for clinical diagnosis of glomerulonephritis.
Biopsy of kidney cortex examined under
• Light microscopy (glomerular and tubular structure)
• Immunofluorescence (looking for Ig and complement)
• Electron microscopy (glomerular basement membrane and deposits)
What is the main risk of a kidney biopsy?
The main risk is bleeding as the kidney is a very vascular organ. There is around a 1% chance of a significant bleed.
What does light microscopy look at in the kidney?
Glomerulus and tubular structure
What does immunoflorescene look at in the kidney?
Looking for IgG and complement
What does electron microscopy look at in the kidney?
Glomerulus BM and deposits.
What is synpharyngitic?
Sore throat and Coca Cola urine
How is nephrotic syndrome classified?
This is classified as:
- 3.5g proteinuria per 24h (urine PCR >300)
- Serum albumin <30
- Oedema
Why is there oedema in nephrotic syndrome?
Urinary loss of albumin results in a decrease in oncotic pressure. This results in peripheral oedema.
What is nephritic syndrome?
- Hypertension
- Blood and protein in urine
- Declining kidney function
What cells are damaged in nephrotic syndrome?
Podocytes
Is IgA nephropathy nephrotic or nephritic?
Nephritis.
This is the most common primary glomerular disease.
What is deposited in the mesangium in IgA nephropathy?
IgA (abnormal production)
About cases of IgA nephropathy will progress to ESFR?
One third
What is the BP aim for IgA nephorapthy?
The most important control is tight BP control. The aim is 125/75. ACEi is the top choice.
Is membranous GN nephritic or nephrotic?
Nephrotic
What antibody is present in membranous GN?
Anti-Phospholipase A2 receptor antibody
What are the possible outcomes of membranous GN?
Variable natural history.
• A third spontaneously remit.
• A third progress to ESRF over 1-2 years.
• A third persistent proteinuria maintain GFR.
What are the treatment options for membranous GN?
- Treat underlying disease if secondary
- Supportive non-immunological – ACEi, statin, diuretics, salt restriction
3. Specific immunotherapy (6 months) • Steroids • Alkylating agents (cyclophosphamide) • Alternative agents – rituximab, anti-CD20 MAb • Cyclosporin
Outcomes – Complete remission, partial remission, ESRD, relapse, death.
What are some examples of conditions that can lead to membranous GN?
10% occur due to secondary to malignancy, CTD and drugs.
What is the commonest GN in children?
Minimal change disease
What type of syndrome does minimal change disease cause?
Nephrotic
What does Minimal change disease show on light microscopy?
Light microscopy is normal whereas electron microscopy shows effacement of podocyte foot processes.
Can Minimal change disease follow an URTI?
Yes
What percentage of people with Minimal change disease will relapse?
50%
What is the treatment of Minimal change disease ?
The treatment is high dose steroids. Prednisolone 1mg/kg for up to 8 weeks.
What type of syndrome does Rapidly progressive GN cause?
Nephritic
What does Rapidly progressive GN show on biopsy?
Crescent shape
What are some causes of Rapidly progressive GN?
Common causes: • ANCA vasculitis (MPO / PR3) • Goodpasture’s syndrome (anti-GBM) • Lupus nephritis • Infection associated: steph and staph • HSP nephritis: IgA nephroapthy
What are the antibodies made in Antineutrophil cytoplasmic antibodies (ANCA)?
Antineutrophil cytoplasmic antibodies (ANCA) are a group of autoantibodies produced when a person’s immune system mistakenly targets and attacks its own neutrophil proteins. Two of the most commonly targeted proteins are myeloperoxidase (MPO) and proteinase 3 (PR3). This results in the production of antibodies to MPO (microscopic polyangiitis) and/or PR3 (GPA)
What is the difference between MPO and PR3?
This results in the production of antibodies to MPO (microscopic polyangiitis) and/or PR3 (GPA)
What is Goodpastures’ syndrome?
Goodpasture’s syndrome is very rare. This is where auto-antibodies target type IV collagen in the glomerular and alveolar basement membrane. There can commonly be lung diease too.
What do antibodies target in Goodpasture’s syndrome?
Type IV collagen.
What are the three embryological structures of kidney development?
- Pronephros
- Mesonephros
- Metanephros
When does urine production occur?
10 weeks
What does nephrogenesis commence?
Week 10
Are there new nephrons at week 36?
No
When does a child achieve an adult GFR?
2 years
What is renal agenesis?
This is congenital absence of renal parenchymal tissue. It occurs at the metanephric stage.
What is renal hypoplasia?
This is the reduction in the number of nephrons. There will be a normal architecture.
What is renal dysplasia?
This is malformed renal tissue
What is hypodysplasia?
Renal Hypodysplasia is congenitally small kidneys with dysplastic features.
What is the inhertitance of ARPKD?
Autosomal recessive
What is oligohydraminois?
Low lowels of amniotic fluid
What are some features of ARPKD?
Clinical presentation: – Antenatal: • Antenatal US • Oligohydramnios: low levels of amniotic fluid – Infancy: • Large palpable renal mass • Respiratory distress • Renal failure: • HT • Hyponatremia: urinary concentrating defect – Childhood: • Renal failure • HT
Is congenital hepatic fibrosis associated with ARPKD?
Yes
What is the rate of progresion to ESRF from ARPKD?
50%
What is the genetic associated with ADPKD?
– PKD1 mutation – cc 16: 85% ; polycystin 1
– PKD2 mutation – cc 4: 10-15%; polycystin 2
What is the most common mutation in ADPKD?
PDK1
What is seen on ultrasound with ADPKD?
Large echogenic kidneys and microcytes
Where do cysts form from in ADPKS?
Tubules
What are some associated anomalies with ADPKS?
Assoc. Anomalies: – Mitral valve prolapse – Cerebral Aneurysm – AV malformation – Hepatic/pancreatic cysts – Colonic diverticula/hernia – Management – Supportive – Directed : Tolvaptan
What is hydronephrosis?
Swelling of the kidney due to a build of fluid
What sex is more affected with hydronephrosis?
Males
What is PUJ obstruction?
This occurs in 1 in 500 births. There is partial/total blockage of urine at ureter junction with kidney.
What sex is more affected by PUJ obstruction?
Males
How much is the uterer dilated in VUJ obstruction?
> 7mm
What are some symptoms of posterior urethral valves?
Some symptoms include: • an enlarged bladder, so that it can be felt through the abdomen as a lump • urinary tract infections (UTIs) • difficulty urinating • a weak stream of urine • unusually frequent urination • bed wetting after toilet training has been successful • poor weight gain
What is Vesico-ureteric Reflux?
This is retrograde passage of urine from bladder into upper urinary tract.
How many grades are in Vesico-ureteric Reflux?
5
What sex is more affected by UTIs under 3 months?
Boys
What sex is more affected by UTIs over 3 months?
Girls
Does circumcision increase or decrease the risk of getting a UTI?
Decrease
What are some symptoms of an upper tract UTI?
• Upper Tract – Pyrexia (Rigors) – Vomiting – Systemic upset – Abdo pain
What are some symptoms of an lower tract UTI?
• Lower Tract – Dysuria – Frequency – Haematuria – Wetting
What is Von Hippel Lindau?
Von Hippel Lindau: rare, AD.
Multisystem – kidneys, pancreas and genital tract.
Multiple cysts – benign with potential for malignant transformation (clear cell carcinoma). Tumours tend to appear in early adulthood.
What tumour is at increased risk in Von Hippel Lindau?
Clear cell carcinoma
What is the hesitance of Von Hippel Lindau??
AD
What is the inheritance of Tuberous Sclerosis?
AD
What is Tuberous Sclerosis?
Tuberous Sclerosis: AD and is multisystem.
Benign tumours – brain, kidneys, heart, eyes, skin.
Seizures, developmental delay, Kidneys – tumours called angiomyolipomas. Risk of haemorrhage.
Rarely to progress to ESRD.
What type of tumours are at increased risk in Tuberous Sclerosis?
Angiomyolipomas
What chromosome is PDK one on?
16
What chromosome is PDK two on?
4
What do the gene PKD code for?
Polycystin
What are some extra-renal manifestations of APKD?
- intracranial aneurysms
- HTN
- valvular abnormalities
- hepatic cysts and pancreatic cysts
- bronchioctasis
What is Tolvaptan?
This is a vasopressin V2 receptor antagonist.
the side effects are hepatotoxicity and hypernatremia.
People will have to drink 6-8 litres a day.
What is the inheritance of Alport’s syndrome?
X-linked
What is mutated in Alport’s syndrome?
COL3A5 which codes for collagen four
Can there be deafness in Alport’s syndrome?
Yes: sensorineural
What is the inheritance of Fabrys?
X-linked
What is deficient in Fabry’s disease?
Alpha galactosidase A deficiency causing accumulation of Gb3
What are some functions of the kidney?
- metabolic waste excretion
- endocrine functions
- drug metabolism/excretion
- BP control
- acid/base
- control of solutes and fluid status
Describe the Glomerular filtration barrier
The renal corpuscle contains the glomerulus and Bowman’s capsule.
The glomerulus is supplied by the afferent artery. the capillaries are fenestrated. This means that red and white blood cells are unbale to pass through.
The basement membrane, which is under the endothelium, is negatively charged. This means that plasma proteins are unable to pass through.
Bowman’s capsule is made up of a visceral and parietal layer. The visceral layer is made of podocytes. In-between are nephrin proteins.
The podocytes have long process and pedicles which wrap around the capillaries and leave filtration slits.
What protein does urine dip sick detect?
albumin
Is creatinine affected by diet?
Slightly
What is creatinine a breakdown product of?
Muscle
What is the MDRD4 formula based on?
Plasma creatine concentration, age, gender and race
How is MDRD4 formula expressed?
It is given as ml/min per 1/73m2 body surface area.
Is GRF exponential with creatinine?
Yes
Is eGFR accurate when it is <60ml?
No
Is eGFR accurate when under 18 years?
No
What is the normal GFR?
100ml
What is CKD 1?
> 90
What is CKD 2?
60-89
What is CKD 3?
30-59
What is CKD 4?
15-29
What is CKD 5?
<15
What percentage of diabetes are diagnosed with kidney problems?
30-40%
What is the first sign of diabetes nephroapthy?
Microalbunuria (not detected by a stranded dip stick)
What is the pathogenesis of diabetic nephropathy?
Hyperglycaemia leads to increased growth factors, RAAS activation, production of advanced glycosylation end-products and oxidative stress.
This causes increase glomerular capillary pressure, podocyte damage and endothelial dysfunction.
Albuminuria is the first sign. There will then be nodule formation and fibrosis.
The process is: Hyperglycaemia Volume expansion Intraglomerular hypertension Hyperinfiltration Proteinuria Hypertension and renal failure
Will an ACEi deterioration renla artery stenosis?
Yes
is RAAS unregulated in renal artery stenos?
Yes
What is the effect on renal size in renal artery stenosis?
> 1.5cm
What is the treatment of renal artery stenos?
Management:
Medical:
• BP control (not ACEi/ARB)
• statin
• if diabetic, good glycaemic control
Lifestyle
• smoking cessation
• exercise
• (low sodium diet)
Angioplasty
• rapidly deteriorating renal failure
• uncontrolled ↑BP on multiple agents
• flash pulmonary oedema
How long are amyloid fibrils?
8-10nm
How is amyloid stained?
congo red
What are the two types of amyloidosis?
There are two types:
- AL: light chain see nin Myeloma
- AA: too much serum amyloid associated protein that is seen in inflammatory diseases for example TB, RA and IBD
What are some examples of antibodies present in systemic lupus?
There is the presence of many antibodies for example direct against double stranded DNA (dsDNA).
What sex is more affected by systemic lupus arythmatosus?
Females
Why is there a low count of C4 in SLE?
There are immune complexes that accumulate and activate complement. This results in low C4 and renal damage.
What is a common presentation of SLE?
Presentation:
- Rash
- Photosensitivity
- Ulcers
- Arthritis
- Serositis
- CNS effects
- Cytopenia’s
- Renal disease
What is acute kidney injury?
Acute kidney injury is a syndrome of decreased renal function, measured by serum creatinine or urine output, occurring over hours-days.
What are the three features of AKI?
AKI:
- Rise in creatinine >26umol/L within 48 hours
- Rise in creatinine >1.5 x baseline within 7 days
- Urine output <0.5mL/kg/hour for 6 consecutive hours
What are some causes of AKI?
- sepsis
- major surgery
- cariogenic shock
- drugs
- hepatorenal syndrome
- obstruction
What is oliguria defined as?
Oliguria is urine output that is less than 1 mL/kg/h in infants, less than 0.5 mL/kg/h in children, and less than 400 mL or 500 mL per 24h in adults.
Out of oliguric and non-oliguric, which is easier to mange?
Non-oliguric
What are e-Alerts?
Electronic alerts (e-alerts) for AKI have been introduced in the UK in order to facilitate earlier detection and improve management.
This is calculated:
- Serum creatinine ≥1.5 times higher than the median of all creatinine values 8–365 days ago
- Serum creatinine ≥1.5 times higher than the lowest creatinine within 7 days
- Serum creatinine >26 µmol/L higher than the lowest creatinine within 48 h
Give some examples of pre-renal causes of AKI?
- haemorrhage
- D and V
- burns
- cariogenic shock
- sepsis
- drugs and toxins
- hypotension
- hypoxia
What is the pathology of pre-real causes of AKI?
There is decreased vascular volume and cardiac output. There will be systemic vasodilation and renal vasoconstriction
What is the pathology of renal causes of AKI?
There is damage to the kidney cells
What are some causes of renal AKI?
- GM
- ATN
- Drugs
- Vasculitis
What is the pathology of post-renal causes of AKI?
There is obstruction.
What is the causes of post-renal causes of AKI?
- stones
- malignancy
- clot
- lymph nodes
- prostate
What is the most common cause of post-renal AKI in males?
Prostate
What is the most common causes of intrinsic AKI?
Acute tubular necrosis accounts for 80%
Can gentamicin cause AKI?
Yes
What is rhabdomyolysis?
Skeletal muscle is broken down very quickly. There is then the release of the contents into the extracellular space. An increase in cytokine ad decrease in NO cause renal vasoconstriction. Myoglobin will be filtered by the glomeruli causing obstruction and inflammation.
What is acute tubular necrosis?
There is prolonged renal hypo-perfusion causing intrinsic renal damage.
What are some causes of ATN?
- Hypotension
- Sepsis
- Toxins
- Or often, all three
What are some examples of exogenous toxins that can cause AKI?
- Drugs (eg, NSAID’s gentamicin, ACEinh)
- Contrast
- Poisons (eg, metals, antifreeze)
What are some examples of endogenous toxins that can cause AKI?
Endogenous • Myoglobin • Hemoglobin • Immunoglobins • Calcium • Urate
Why can’t NSAIDs be used in AKI?
When pressure falls, prostaglandins dilate the afferent arteriole to increase flow.
NSAIDs reversibly inhibit the production of renal prostaglandins via their inhibition of COX-1 and COX-2. Renal prostaglandins cause dilatation of the renal afferent arteriole. This mechanism is important for maintaining GFR when renal blood flow is reduced.