Renal Flashcards
What group of people are most affected by Acute Kidney Injury?
Elderly
What are Pre-Renal Causes of Acute Kidney Injury?
=Reduced renal function with no structural damage to the kidneys
Common examples:
-Haemorrhage
-Hypovolaemia
-SEPSIS
-Heart Failure
-Nephrotoxics
-Renovascular disease (e.g Renal Artery Stenosis)
Name 5 types of drugs that are Neprotoxic.
-ACE inhibitors
-Diuretics
-NSAIDs
-Aminoglycosides
-B Lactams
How are ACE inhibitors Nephrotoxic?
They dilate the efferent arterioles in the Kidney which DECREASES the Glomerular Filtration Rate.
What are Renal Causes of Acute Kidney Injury?
–>Acute Tubular Necrosis (ATN)
-Tubular cell death (either due to
-Ischaemia or Nephrotoxins)
-Ischaemia
-Nephrotoxins
–>Acute Interstitial Nephritis
-Mainly due to medication side effects
A patient comes in with Endocarditis. A few days later after treatment, they develop Acute Kidney Injury. What drug given was most likely responsible?
Aminoglycosides - Nephrotoxic!!
(e.g Gentamiacin)
(given in severe illness as it is a strong antibiotic targetting Gram-Negative bacteria - given to patients with infective endocarditis, sepsis, complicated intraabdominal infections)
Name the most common Aminoglycoside.
Gentamicin
What is the most common causes of Acute Kidney Injury?
Acute Tubular Necrosis (ATN)
-70% of cases
What is the prognosis of a patient with Acute Tubular Necrosis and why?
Good recovery.
=Just as the tubules of the kidney are most susceptible to damage due to their HIGH METABOLIC ACTIVITY AND REGULAR CELL RENEWAL, this also means that once the underlying condition is treated, they recover well!:)
What are the main causes Acute Intestinal Nephritis?
ALMOST ALWAYS DUE TO MEDICATION SIDE EFFECTS OF THE FOLLOWING:
-Beta Lactams (e.gPenicillins, Cephalosporins,Carbapenems)
-NSAID use
A patient presents with a gradual onset of fever and rash. Blood results show high Eosinophils. What does that indicate. What could have caused this?
High Eosinophils = Eosinophilia
~ Classic triad for Acute Intestinal Nephritis.
Persistent use of NSAIDs or use of Beta Lactams causing Acute Intestinal Nephritis
A patient has Acute Interstial Nephritis. What should be done to manage it?
-Withdraw causative agent
-Prescribe Steroids
What are Beta lactams and give some examples?
First choice for GRAM NEGATIVE BACTERIAL INFECTIONS
- Penicillin
- Carbapenems
- Cephalosporins
List some common Gram Negative infections.
-Pneumonia (Klebsiella pneumoniae)
-Peritonitis
-UTIs
-Meningitis
-Salmonella
-Shingles
-Typhoid Fever
-E.coli infections
A patient presents with a fever, general malaise, pruritus, palpitations and peripheral oedema. Patient was already in the hospital with Pneumonia. What seems most likely to have caused these symptoms?
Symptoms sound like Acute Kidney Injury
=caused by the Beta-Lactams given for the Pneumonia which has caused Acute Intestinal Nephritis
What are the Post-Renal causes of Acute Kidney Injury?
–>Obstruction to urinary outflow tract
-Tumours
-Clots
-Calculi
-Strictures
How does obstruction cause Acute Kidney Failure?
1.Build up of renal pressure
2.Causes atrophy of renal cells
3.Leukocyte infiltration and cytokine release
What are the complications of renal failure ?
1.Uraemia (high urea/ nitrogen from waste)
2.Hyperkalaemia
3.Acidosis
4.Fluid Overload
What is the presentation of Uraemia?
-General Malaise
-Pruritus
-Paraesthesia
-Altered Mental State
-Pericardial rub
-Pale Skin
What is the presentation of Hyperkalaemia?
Palpitations and Chest pain
What is the presentation of Acidosis?
Kussmaul breathing and Confusion
What is Kussmaul breathing?
Abnormal breathing pattern characterized by RAPID AND DEEP breathing at a consistent pace. It’s a sign of a medical emergency such as DKA or AKI.
What is the presentation of Fluid Overload?
Peripheral Oedema
Breathlessness
Raised JVP
What are contrast agents?
Agents used in imaging such as Xrays, CT, MRIs used to distinguish structures
A patient is required to take a contrast agent for their CT. What should be done to avoid WHAT emergency?
Aggressive Hydration
=AVOID AKI
What is the criteria for diagnosing AKI?
If any of the following are present:
–>Serum Creatinine rise
>26mmol/L within 48hrs
>50% rise within the past week of 1.5fold of baseline
–>Urine output decrease
<0.5ml/kg/hr for >6hrs in Adults and >8hrs in Children
–>eGFR decrease
>25% decrease in CHILDREN AND YOUNG PEOPLE
What in particular needs to be monitored in an AKI patient?
Their Serum Creatinine
What investigations into the underlying causes of AKI need to be done?
1.Medication review
2.Urinalysis
3.Blood tests (FBC, U&E, LFT, Glucose coagulation)
4.ECG
5.Fractional Excretion of Sodium
5.Urgent Renal ultrasound
6.Imaging
What does the Fractional Excretion of Sodium indicate about a patient with AKI?
<1% = Pre-Renal Cause
>2% =Most likely Acute Tubular Necrosis (ATN)
When would an AKI patient require a Urology / Nephrologist referral?
-If Post-Hepatic (Obstruction)
-Unresponsive to medical treatment
-If Renal replacement therapy is indicated
When is Renal Replacement therapy indicated in an AKI patient?
A HOPE
1.Acidosis
2.Hyperkalaemia
3.Oedema (general and pulmonary)
4.Pericarditis - Complications of uraemia
5.Encephalopathy (Complications of uraemia)
What 2 conditions can Uraemia cause?
-Pericarditis
-Encephalopathy
What is the treatment of an AKI?
–>Supportive
-Fluid balance monitoring (and daily weights)
-Review medications (may need to stop potentially nephrotoxic drugs)
-O2 if breathless
-Transfusion if anaemia
-Twice / daily U&Es
What is Rhabdomyolysis?
Skeletal Muscle breakdown releasing cellular contents that cause AKI and electrolyte abnormalities.
List common causes of Rhabdomyolysis.
1.Alcoholism
2.DKA
3.Infections
4.Ischaemia
5.Trauma (specifically crush injuries or burns)
6.Falls
7.Long lie (when a person has fallen and spends a prolonged period of time on the floor)
8.Compartment Syndrome
9.Seizures
10.Statin (small risk <1%)
What are the clinical features of Rhabdomyolysis?
-Reddish brown (tea coloured) urine
-Muscle swelling, pain or limb
paraesthesia
-Fever, Nausea, Vomiting
-Hyperkalaemia
-Hypocalcaemia
How would you diagnose Rhabdomyolysis?
-Urinalysis = Haematuria
-Hyperkalaemia, Hypocalcaemia and Hyperphosphataemia
-Creatinine is SIGNIFICANTLY elevated (5times baseline)
What is the management of Rhabdomyolysis?
-Aggressive Fluid therapy (and correction of electrolyte imbalance)
What is meant by a Long Lie?
When a person has fallen and spends a prolonged period of time on the floor = this can have devastating complications such as
-Pressure ulcers
-Pneumonia
-Rhabdomyolysis
What is Chronic Kidney Disease?
Kidney damage for 3 or more months that can be caused by structural functional disorders presenting with a low eGFR of <60ml/min/1.73m^2
What eGFR defines Kidney Failure?
<15 eGFR
What 2 measurements can indicate the prognosisof Chronic Kidney Disease?
Increased Albumin/Creatinine Ration and Decreased eGFR
=Poorer Outcome
IF THEY OCCUR TOGETHER THE RISK IS MULTIPLIED
What group of people may have a low eGFR than the average level?
Bodybuilders
Who would you more commonly see Chronic Kidney disease in?
-Older patients with
-Diabetes Mellitus
-Hypertension
-Afrocarribean and Asian populations
What are the symptoms of Chronic Kidney Disease?
=Asymptomatic until LATE STAGE :
-Pruritus
-Polyuria
-Oedema
-Fatigue
-Muscle weakness
Patients with Chronic Kidney Disease usually have Comorbidities. What are the common ones to be seen in CKI patients?
-Coronary Artery Disease
-Hypertension
-Dyslipidaemia
-Mineral and Bone Disorders
What investigations are to be done for a suspect Chronic Kidney Disease?
1.Assess Kidney Function
-eGFR
-Urine Albumin : Creatinine Ratio
2.Blood tests and dipstick
-Anaemia?
-Autoantibody testing (for underlying disease)
3.Renal Ultrasound if symptoms indicate:
-Obstruction
-Polycystic disease
-Visable/Microscopic Haematuria
When should a Renal ultrasound be done?
-Symptoms of Obstruction
-Accelerated progression of disease
-Family history of Polycystic Kidney Disease
-Visable/ Microscopic Haematuria
What blood test results would you expect from a patient with Chronic Kidney Disease?
Normochromic Normocytic Anaemia
What lifestyle advice would be given to a patient diagnosed with Chronic Kidney Disease?
-Stop smoking
-Diet: Lower calories, potassium, phosphate and salt intake
!DO NOT SUGGEST LOW PROTEIN DIET
-Avoid Nephrotoxic medications (e.g NSAIDs, Beta Lactams)
What is the target blood pressure for a patient with Chronic Kidney Disease?
<140/90
But if Albumin / Creatinine ratio is VERY high i.e >70
=<130/80
What are the 5 secondary consequences of Chronic Kidney Disease that need to be managed and how?
1.BP
=ACE inhibitors
2.CVD
=Statins and Antiplatelet agents
3.Anaemia
=Erythropoietic-stimulating agent
4.Oedema
=Loop Diuretic
5. Renal Bone Disease and Electrolyte abnormalities
-Measure calcium, phosphate, PTH and Vit D if eGFR is <30
-Bisphosphonates
Give examples of Erythopoietic Stimulating Agents.
Poetin, Darbepoetin
What drug given to patients with Chronic Kidney Injury cannot be given routinely to patients with Acute Kidney Injury?
Loop Diuretics (e.g Furosemide)
A patient has a eGFR of 18. What additional management will they have included?
1.End-stage disease indicated by low eGFR
Severe: 15-29
Kidney Failure: <15
=Renal Replacement Therapy
2.eGFR is <30 so check Calcium, Phosphates , PTH and VitD etc
= Bisphosphonates
Name 3 types of Glomerulonephritis.
1.Nephrotic Syndrome
2.Nephritic Syndrome
3.Mixed Nephrotic and Nephritic
Name 3 causes of Nephrotic Syndrome.
1.Minimal Change Nephropathy
2.Focal Segmental Glomerulosclerosis (FSGS)
3.Membranous Nephropathy
What is Nephrotic Syndrome characterised by?
1.Proteinuria
>3g/24hrs OR Urine/Creatinine Ratio >300mg/mol
2.Hypoalbuminaemia
<25g/L
-Associated with Hyperlipidaemia
3.Oedema
4.Hyperlipidaemia
(Xanthoma)
What is the most common cause of Nephrotic Syndrome in Children?
90% of cases
=Minimal Change Nephropathy
What is the cause/ pathophysiology of Minimal Change Nephropathy?
Idiopathic
What is the presentation of Minimal Change Nephropathy?
-Fatigue
-Peripheral or General Oedema
-Features of nephrotic syndrome (proteinuria, low albumin and hyperlipidemia)
What changes will be seen on microscopy of a patient with Minimal Change Nephropathy?
Normal Light Microscopy
BUT
-Podocyte fusion on electron microscopy
What is Focal Segmental Glomerulosclerosis?
Idiopathic disorder whereby part of the glomerulus is affected that causes Nephrotic Syndrome (accounts for 15% of cases)
Who is more likely to have Focal Segmental Glomerulosclerosis?
-Afro-Caribbean Populations
-HIV
-Drug abusers (heroin in particular)
What would a biopsy show for a patient with Focal Segmental Glomerulosclerosis?
IgM deposition
What is the treatment for Focal Segmental Glomerulosclerosis?
1.Steroids
2.Immunosuppressive agents if unresponsive to Steroids
What is the treatment for Minimal Change Nephropathy?
Prednisolone
What is the prognosis for Minimal Change Nephropathy?
Recover after 6-8weeks with Prednisolone but remission is frequent
What is the prognosis for Focal Segmental Glomerulosclerosis?
50% of patients progress, 50% experience remission
What is the most common cause of Nephrotic Syndrome in adults?
Membranous Nephropathy
What are the causes of Membranous Nephropathy?
-Idiopathic (majority)
-Malignancy (Lung and Colon)
-Autoimmune Diseases
-Penicillamine use (used in Willson’s and Rheumatoid Arthiritis)
What is used to diagnose Membranous Nephropathy?
Biopsy:
-IgG deposits (in a Spike and Dome patterned)
What is the treatment for Membranous Nephropathy?
Steroids and immunosuppressive drugs (Rituximab)
What is the prognosis for Membranous Nephropathy?
1/3 - Spontaneous Remission :)
1/3 - Respond to treatment
1/3 - Progress to End-stage disease
Describe examples of general oedema.
-Peri-orbital (eyes)
-Ascites
-Lower limb
What is the main difference between Nephrotic and Nephritic when diagnosing.
Nephrotic
Protein increase > Blood presence
+Prominent Creatinine increase and Hypertension
Nephritic
Blood presence > Protein increase
+Red cell casts
What is Nephrotic Syndrome characterised by?
-Haematuria
-Hypertension
-Associated proteinuria with oedema
What are the 5 causes of Nephritic Syndrome?
1.Thin Basement Membrane Disease
2.IgA Nephropathy (Berger Disease)
3.Post-streptococcal Glomerulonephritis (PSGN)
4.Rapidly Progressive Glomerulonephritis aka Crescentic GN
5.Granulomatosis with Polyangiitis