Nephro Flashcards
Causes of Acute interstitial nephritis
- drugs: the most common cause, particularly antibiotics
penicillin
rifampicin
NSAIDs
allopurinol
furosemide
- systemic disease: SLE, sarcoidosis, and Sjögren’s syndrome
- infection: Hanta virus , staphylococci
Features of Acute interstitial nephritis
fever, rash, arthralgia
eosinophilia
mild renal impairment
hypertension
Investigations of acute interstitial nephritis
sterile pyuria
white cell casts
Tubulointerstitial nephritis with uveitis(TINU) usually occurs in ……?
young females.
Criteria to diagnose AkI
- rise in serum creatinine of >= 26 micromol/litre within 48 hours
- 50% or greater rise in serum creatinine known or presumed to have occurred within the past 7 days
- urine output < 0.5 ml/kg/hourfor > 6 hours in adults and more than
Stage 1 of AKI
- urine output to<0.5mL/kg/hour for≥ 6 hours
Or
2. Increase in creatinine to1.5-1.9times baseline
Or
- Increase in creatinine by ≥26.5 µmol/L
Stage 2 of AKI
- urine output to<0.5mL/kg/hour for≥12 hours
Or
- Increase in creatinine to2.0 to 2.9times baseline
Stage 3 of AKi
- urine output <0.3mL/kg/hour for≥24 hours
Or
- Increase in creatinine to≥ 3.0times baseline
Or
- Increase in creatinine to ≥353.6 µmol/L
ADPKD type 1 vs ADPKD type 2
Which Chromosome ….?
Type 1 : Chromosome 16
Type 2: Chromosome 4
Ultrasound diagnostic criteria of ADPKD (in patients with positive family history)
- Age < 30 years ; 2 cysts uni/ bilateral
- Age 30 - 59 years ; 2 cysts in each kidneys
- Age > 60 ; 4 cysts in each kidneys
Management of ADPKD
tolvaptan(vasopressin receptor 2 antagonist) may be an option. For select patients
Extra-renal manifestations of ADPKD
- Liver cysts 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
Causes of a raised anion gap metabolic acidosis
lactate: shock, hypoxia
ketones: diabetic ketoacidosis, alcohol
urate: renal failure
acid poisoning: salicylates, methanol
5-oxoproline: chronic paracetamol use
Causes of a normal anion gap or hyperchloraemic metabolic acidosis
gastrointestinal bicarbonate loss:diarrhoea, ureterosigmoidostomy, fistula
renal tubular acidosis
drugs: e.g. acetazolamide
ammonium chloride injection
Addison’s disease
ARPKD is due to a defect in a gene located on chromosome ….. which encodes ………
Chromosome 6
encodes fibrocystin
Autosomal recessive polycystic kidney disease (ARPKD) on biopsy
Renal biopsy typically shows multiple cylindrical lesions at right angles to the cortical surface.
The time taken for an arteriovenous fistula to develop is …….?
6 to 8 weeks.
Calciphylaxis presents with ……?
painful necrotic skin lesions.
The risk of developing calciphylaxis is linked with
hypercalcaemia,
hyperphophataemia and
hyperparathyroidism.
Treatment of calciphylaxis
reducing calcium and phosphate levels, controlling hyperparathyroidism and avoiding contributing drugs such as warfarin and calcium containing compounds.
What is the most common presenting feature of Retroperitoneal fibrosis?
Lower back/flank pain
Retroperitoneal fibrosis is associated with (4)
Riedel’s thyroiditis
previous radiotherapy
sarcoidosis
inflammatory abdominal aortic aneurysm
drugs: methysergide
Indications for plasma exchange
Guillain-Barre syndrome
myasthenia gravis
Goodpasture’s syndrome
ANCA positive vasculitis if rapidly progressive renal failure or pulmonary haemorrhage
TTP/HUS
cryoglobulinaemia
hyperviscosity syndrome e.g. secondary to myeloma
Complications of plasma exchange
hypocalcaemia: due to the presence of citrate used as an anticoagulant for the extracorporeal system
metabolic alkalosis
removal of systemic medications
coagulation factor depletion
immunoglobulin depletion
Contrast media nephrotoxicity may be defined as a …….%….. increase in creatinine occurring……..days after administration.
25% increase in creatinine occurring2 -5 days after administration.
5 Risk factors of Contrast media nephrotoxicity
known renal impairment (especially diabetic nephropathy)
age > 70 years
dehydration
cardiac failure
the use of nephrotoxic drugs such as NSAIDs
Prevention of Contrast media nephrotoxicity
Iv 0.9% sodium chlorideat a rate of 1 mL/kg/hour for 12 hours pre- and post- procedure
Patients who are high-risk for contrast-induced nephropathy should have metformin withheld for …………..
metformin withheld for a minimum of 48 hours and until the renal function has been shown to be normal.
Spironolactone is analdosterone antagonist which acts in ……
the cortical collecting duct.
Causes of lactic acidosis type A
sepsis, shock, hypoxia, burns
Causes of lactic acidosis type B
metformin
the Modification of Diet in Renal Disease (MDRD) equation, which uses thefollowing 4 variables:
serum creatinine
age
gender
ethnicity
3 Factors which may affect s. Creat
pregnancy
muscle mass (e.g. amputees, body-builders)
eating red meat12 hours prior to the sample being taken
Amyloidosis: types
- AL AMYLOIDOSIS
- AA AMYLOIDOSIS
- Beta 2 microglobulin AMYLOIDOSIS
Causes of AL amyloidosis
myeloma, Waldenstrom’s, MGUS
Causes of AA amyloid
chronic infection/inflammation
e.g. TB, bronchiectasis, rheumatoid arthritis
Beta-2 microglobulin amyloidosis is associated with
patients on renal dialysis
4 Risk factors for urothelial (transitional cell) carcinoma of the bladder include:
- Smoking
- Exposure to aniline dyes
- Rubber manufacture
- Cyclophosphamide
2 Risk factors for squamous cell carcinoma of the bladder include:
Schistosomiasis
Smoking
What is the investigation of choice of Renal vascular disease?
MR angiography
Management of Wilms’ nephroblastoma
nephrectomy
chemotherapy
radiotherapy if advanced disease
Renal cell cancer is associated with (3)
von Hippel-Lindau syndrome
tuberous sclerosis
autosomal dominant polycystic kidney disease
Features of which condition?
haematuria
loin pain
abdominal mass
paraneoplastic hepatic dysfunction syndrome
Stauffer syndrome typically presents ascholestasis/hepatosplenomegaly
Renal cell cancer
Which type of renal stones is radio lucent
Urate stones
Xanthine stones
stag-horn calculi are composed of…
struvite (ammonium magnesium phosphate, triple phosphate).
Renal stones: risk factors
dehydration
hypercalciuria, hyperparathyroidism, hypercalcaemia
cystinuria
high dietary oxalate
renal tubular acidosis
medullary sponge kidney, polycystic kidney disease
beryllium or cadmium exposure
2 Risk factors for urate stones
gout
ileostomy: loss of bicarbonate and fluid results in acidic urine, causing the precipitation of uric acid
4 drugs that promote calcium stones
steroids,
acetazolamide,
loop diuretics,
theophylline
- SALT
alpha blockers recommend in renal stones
for distal ureteric stones < 10 mm in size
ultrasound should be used in renal stones for ……
pregnant women and children
Which drugs can be used to prevent Oxalate stones?
cholestyramine reduces urinary oxalate secretion
pyridoxine reduces urinary oxalate secretion
In Pre renal uremia
- Urine sodium
- Urine osmolality
- Fractional Na excretion
- Fractional Urea excretion
- Serum Urea: creatinine ratio
- Urine:plasma urea
- Urine:plasma osmolality
- Specific gravity
- Urine sodium : < 20
- Urine osmolality >500
- Fractional Na excretion < 1 %
- Fractional Urea excretion < 35%
- Serum Urea: creatinine ratio : raised
- Urine:plasma urea > 10:1
- Urine:plasma osmolality > 1.5
- Specific gravity > 1020
In ATN
- Urine sodium :
- Urine osmolality
- Fractional Na excretion
- Fractional Urea excretion
- Serum Urea: creatinine ratio
- Urine:plasma urea
- Urine:plasma osmolality
- Specific gravity
- Urine sodium : > 40
- Urine osmolality < 350
- Fractional Na excretion > 1 %
- Fractional Urea excretion > 35 %
- Serum Urea: creatinine ratio : normal
- Urine:plasma urea < 8:1
- Urine:plasma osmolality < 1.1
- Specific gravity < 1010
fractional sodium excretion =
*fractional sodium excretion = (urine sodium/plasma sodium) / (urine creatinine/plasma creatinine) x 100
fractional urea excretion =
fractional urea excretion = (urine urea /blood urea ) / (urine creatinine/plasma creatinine) x 100
corticomedullary scarring with atrophy of tubules
Seen in …?
Chronic pyelonephritis is
Risk factors of Chronic pyelonephritis
vesicoureteral reflux in children
obstruction e.g.recurrent renal stones
Red cell casts present in: 4 conditions
- Acute glomerulonephritis
- Renal vasculitis
- Accelerated hypertension and
- Interstitial nephritis.
Alport’S SYNDROME is due to a defect in the gene which codes for ……
type IV (4) collagen resulting in an abnormal glomerular-basement membrane
Alport’S SYNDROME is more severe in …….
Males
In Alport’S SYNDROME, deafness occurs……
Before the onset of renal failure
90% of Alport’s syndrome develop renal failure by the age of….
40 years
Alport’s patient with a failing renal transplant. This may be caused by the presence of …..
anti-GBM antibodies leading to a Goodpasture’s syndrome like picture.
5 features of Alport’S SYNDROME
- Microscopic haematuria.
2) Progressive renal failure.
3) Bilateral sensorineural deafness.
- Ocular abnormalities: Lenticonus, corneal ulceration, cataract, retinitis pigmentosa
- Renal biopsy: splitting of lamina densa seen on electron microscopy, light microscopy may be unremarkable.
A definitive diagnosis of Acute interstitial nephritis is established by
Renal biopsy which usually shows interstial oedema with a heavy infiltrate of inflammatory cells and variable tubular necrosis
Mechanism of acute interstitial nephritis
delayed T-cell hypersensitivity or cytotoxic T-cell reaction.
5 Causes of Papillary necrosis
- Chronic analgesia use
- Sickle cell disease
- TB
- Acute pyelonephritis
- DM
Retroperitoneal fibrosis is associated with ( 5)
- Riedel’s thyroiditis
- Previous radiotherapy
- Sarcoidosis
- Inflammatory abdominal aortic aneurysm
- Drugs: methysergide