Nephrology Flashcards
How much does creatine kinase levels need to be raised to suspect rhabdomylosis?
5 times
What does insulin/dextrose infusion do?
Shifts potassium from extracellular to intracellular fluid compartments
Bloods in post-streptococcal glomerulonephritis?
raised anti-streptolysin O titre are used to confirm the diagnosis of a recent streptococcal infection
low C3
Size of kidneys normally in CKD?
Bilaterally small kidneys
Exceptions to this rule include:
autosomal dominant polycystic kidney disease
diabetic nephropathy (early stages)
amyloidosis
HIV-associated nephropathy
Why is increased risk of thromboemobilsm in neprhotic syndrome?
Due to loss of antithrombin III and plasminogen in the urine
What is Wilms’ nephroblastoma
one of the most common childhood malignancies. It typically presents in children under 5 years of age, with a median age of 3 years old.
Features
abdominal mass (most common presenting feature)
flank pain
painless haematuria
other features: anorexia, fever
unilateral in 95% of cases
metastases are found in 20% of patients (most commonly lung)
Features of acute interstital nephritis?
fever, rash, arthralgia
eosinophilia
mild renal impairment
hypertension
What is the treatment of nephrogenic diabetes and why?
thiazide diuretic
Why?
In simple terms DI leads to the production of vast amounts of dilute urine which is dehydrating and raises the plasma osmolarity, stimulating thirst. The effect of the thiazide causes more sodium to be released into the urine. This lowers the serum osmolarity which helps to break the polyuria-polydipsia cycle.
What causes haemolytic uraemic syndrome?
E coli
Fluid replacement
First 10kg 100ml/kg
Second 10kg 50ml/kg
Subsequent kg 20ml/kg
Extra-renal manifestations of Autosomal dominant polycystic kidney disease
liver cysts (70% - the commonest extra-renal manifestation): may cause hepatomegaly
berry aneurysms (8%): rupture can cause subarachnoid haemorrhage
cardiovascular system: mitral valve prolapse, mitral/tricuspid incompetence, aortic root dilation, aortic dissection
cysts in other organs: pancreas, spleen; very rarely: thyroid, oesophagus, ovary
Extra-renal manifestations of Autosomal dominant polycystic kidney disease
liver cysts (70% - the commonest extra-renal manifestation): may cause hepatomegaly
berry aneurysms (8%): rupture can cause subarachnoid haemorrhage
cardiovascular system: mitral valve prolapse, mitral/tricuspid incompetence, aortic root dilation, aortic dissection
cysts in other organs: pancreas, spleen; very rarely: thyroid, oesophagus, ovary
Normal anion gap metabolic acidosis?
gastrointestinal bicarbonate loss: prolonged diarrhoea: may also result in hypokalaemia, ureterosigmoidostomy
fistula, renal tubular acidosis
drugs: e.g. acetazolamide
ammonium chloride injection
Addison’s disease
Management of autosomal dominant polycystic kidney disease?
Tolvaptan
Management of minimal change disease?
oral corticosteroids: majority of cases (80%) are steroid-responsive
cyclophosphamide is the next step for steroid-resistant cases
Causes of nephrogenic DI
genetic:
more common form affects the vasopression (ADH) receptor
less common form results from a mutation in the gene that encodes the aquaporin 2 channel
electrolytes:
hypercalcaemia
hypokalaemia
lithium:
lithium desensitizes the kidney’s ability to respond to ADH in the collecting ducts
demeclocycline
tubulo-interstitial disease: obstruction, sickle-cell, pyelonephritis
Alport memory aid
Can’t see- Lenticuonus
Can’t pee- Haematuria/CKD
Can’t hear a high C- Senorineural hearing loss
Most common cause of peritonitis?
coagulase-negative staphylococci such as Staphylococcus epidermidis is the most common cause. Staphylococcus aureus is another common cause
Anion gap?
(Na+ + K+) - (Cl- + HCO-3)
What are eosinophilic casts a qsign of?
Tubulointerstitial nephritis
How does acute tubular necrosis respond to fluid challenge?
Poorly
HyperK >6.5? Remember CAN
- Calcium gluconate 10% 10ml by slow IV titrated to ECG response
- Actrapid 10U in 50ml 50% glucose in 15minutes
- Neb Salbutamol
Next step if blood sample 6.4
Perform an ECG
Causes of focal segmental glomerulosclerosis?
idiopathic
secondary to other renal pathology e.g. IgA nephropathy, reflux nephropathy
HIV
heroin
Alport’s syndrome
sickle-cell
Management of proteinuria in CKD?
Ace inhibitors
Ratio used when identifying patients with proteinuria?
Albumin:creatinine ratio
Drug that stabilises cardiac membrane?
IV calcium gluconate
Risk if 0.9% saline is used?
if large volumes are used there is an increased risk of hyperchloraemic metabolic acidosis
Post-streptococcal glomerulonephritis cause?
immune complex (IgG, IgM and C3) deposition in the glomeruli
Features of post strep glomeulonephritis?
general
headache
malaise
visible haematuria
proteinuria
this may result in oedema
hypertension
oliguria
What is Dialysis disequilibrium syndrome
rare complication and usually affects those who have recently started renal replacement therapy. It is caused by cerebral oedema, but the exact mechanism is unclear. Therefore this is a diagnosis of exclusion.
Causes of renal artery stenosis in an old guy?
Atherosclerosis
What does kidney sense in renal artery stenosis?
Hypotension
Therefore RAAS system activated
Then leads to hypertension
Causes of secondary hyperparathyroidism?
Higher blood phosphorus levels
The kidneys cannot make active vitamin D (needed to absorb calcium)
Lower blood calcium levels
Recommended fluid challenge for patients with no clincial signs or documentation of HF?
500 ml of normal saline stat
Causes of intrinsic AKI?
glomerulonephritis
acute tubular necrosis (ATN)
acute interstitial nephritis (AIN), respectively
rhabdomyolysis
tumour lysis syndrome
What rate shoild maintaince fluids be prescribed?
30 ml/kg/24hr.
Screening for diabetic nephropathy?
all patients should be screened annually using urinary albumin:creatinine ratio (ACR)
should be an early morning specimen
ACR > 2.5 = microalbuminuria
Treatment of clot retention?
Continueous bladder irrigation
What is hyperacute rejection?
occurs minutes to hours after re-vascularisation of the transplanted kidney. It is due to pre-existing antibodies in the recipient’s blood, such as ABO antibodies. This type of rejection is very rare now due to the sensitivity of cross-matching but risk factors include:
Previous blood transfusions
Previous transplants
Multiple pregnancies
Pre renal uraemia urine osmolarity
More than 500mOsm/kg
Urine sodium in pre-renal uraemia?
Urine sodium less than 20
Symptoms of a negative fluid balance?
Hypotension
Oliguria
Sunken eyes and reduced skin turgor
Tachycardia
What does calcium resonium do?
removal of potassium from the body, rather than shifting potassium between fluid compartments in the short-term
IV fluid resusistation how long give inital bolus
Over less than 15 minutes
Does hypocalcemia suggest CKD and AKI?
CKD
A helpful mnemonic to remember the drugs to stop in AKI is DAMN AKI:
Diuretics
Aminoglycosides and ACE inhibitors
Metformin
NSAIDs.