renal Flashcards
what are the different types of renal stones
Calcium oxalate, 65%
Calcium phoshphate 20%
Uric acid 10%
epidemiology and prevalence of renal stones
lifetime risk 10-15% age 20-40 is peak
Risk factors of stone formation
Dehydration - largest risk factor pre existing kidney disease PCKD UTI- Proteus Urinary factors - Hypercalcemia thiazide= increase uric acid
Prevention of stone formation
Overhydration reduce salt and sodium normal dairy moderate protein reduce BMI
where can stones form
upper, renal pelvis or ureter
lower bladder urethra prostate
Presentation of renal stones
Majority asymptomatic renal colic (associated with nausea and vomiting) Pallor sweating haematuria Auria UTI symptoms, voiding symptoms no signs on examination ( look out for gout tophi as a sign of excess uric acid
what is renal colic
severe abd pain, loin to groin
sudden onset
radiates to ipsilateral testicle or labia
writhing pain, unable to find comfortable position
colicky pain
pain usually subsited after a few hours
made worse by exercise or diuretics or alcohol
Investigations and diagnoses of renal stones
Before starting investigations start on Analgesia and antiemetics to stabilize patent
Non contrast CT of kidney ureter and bladder NCCT-KUB - diagnostic of stone
identify cause of stone: Bloods, Serum Ca, Serum uric acid. U and E. MC and S of MSU
differential diagnoses for patient present with renal colic
AAA
Gynae causes, Torsion of ovaries or ruptured ectopic
MSK
Torsion
Management of renal stones
Include preventative measures
Analgesia, NSAIDs, antiemetics
potentially give IV fluid if you want them to pass the stone
watch for sepsis
if stone <1 cm then conservative (hydrain, pain and antiemetic)
stone =2-3cm then lithotripsy (Extracorporeal shock wave lithotripsy)
stone >2cm Ureteroscopic laser
ureteric stent
Prevention of further if hypercalciuria ( thiazide if hyperuricemia (allopurinol)
trimethoprim or gentamycin
Complication of Renal stones
can cause sepsis
obstruction of UT can cause dilation and dilation of the kidney is hydronephrosis. if there was an infection present it could cause pyonephrosis
what is pyonephrosis and presentation
pyelonephritis +hydronephrosis (infection of the kidney) Loin pain fever Nausea and vomiting haematuria proteinuria sterile pyuria leads to sepsis
treatment of pyonephrosis
Iv antibiotics (gentamicin) + oxygen + drain watch for sepsis and potentially transfer to ITU
what does Acute kidney injury mean
Spectrum of kidney disease ranging from mild improvement to full kidney failure requiring RRT
What is creatinine and why is it used in
its a muscle breakdown product that is filtered freely in the kidney and not reabsorbed so gives indication of kidney filtration levels. elevated serum creatinine suggest reduced filtration
criteria to diagnose AKI
> 26 mmol/L rise in serum creatinine
50% increase in serum creatinine
oliguria less than 0.5ml/kg/Hr
what is the time frame for acute kidney injury and chronic kidney injury
3 month
risk factors for kidney injury
Diabetes liver disease sepsis reduced fluid intake age >75 CKD Cardiovascular problems PMH of urinary symptoms urinary symptoms Drugs - NSAIDs and ACEi
why can NSAIDs and ACEi have an effect on Kidney
Prostaglandins cause afferent dilation which improves GFR
Angiotensin 2 causes efferent constriction whic also improves GFR
having ACEi and NSAIDS blocks this and causes Reduced GFR
causes of AKI
commonest are ischemia, sepsis, nephrotoxins
Pre renal - commonest cause (70%)
renal-
Post renal causes- least common
causes of AKI
pre renal
hypoperfusion, any reason. HV shock, D and V , sepsis
ACEi or NSAIDs.
renal artery stenosis
causes of AKI
renal
acute tubular necrosis (commonest renal cause of AKI)
glomerular cause, autoimmune, SLE, or Glomerulonephritis
interstitial, drugs like aminoglycans
vascular: SLE, ischemic, increased BP
causes of AKI
post renal
any obstruction to outflow tract-
lumina, stones, clots
intramural, BPH, Malignancy of bladder, ureter, prostate
extraluminal: compressive malignancy
What can cause Acute tubular nephrosis
nephrotoxins,
myoglobinuria by rhabdomyolysis
name some nephrotoxins
aminoglycans, Vancomycin
Lithium
Methotrexate
assessment and investigations of a patient with AKI
assess history: which drugs they are on, Risk factors PMH Urgent Hyperkalemia examination
Examination: look for palpable kidney (PCKD) bladder or masses in abdomen , check volume status- BP, JVP, edema, skin turgor.
bed tests: Dip stick, looking for nitrates or leukocytes, Microscopy and cultures to look for crystals, cultures
blood tests, U and E, FBC, clotting LFT, ESR, CRP, potentially serology
Imaging- renal USS, CTKUB,
Urgent examination to carry out in AKI
Urgent K+ and ECG checking for Hyperkalemia
Investigations and Imagining of AKI
Ultrasound looking for hydronephrosis or obstruction,
if hydronephrosis and over 65 suspect BPH and catheterise
if not relieved do NCCTKUB to look for stones etc
presentation of AKI
Usually asymptomatic and only detected on Blood tests but can present with nausea vomiting, confusion and a wide variety of symptoms (on another flashcard
Signs and symptoms of AKI
early: nausea, vomiting, reduced urine output, dizziness, lethargy
due to fluid retention, pul odema, nocturnal dyspnea, orthopnea, peripheral oedema
due to B, hyper or hypotension , Orthostatic hypotension, tachycardia
Confusion
haematuria