Renal Medicine Flashcards
What is dysuria and what is uraemia?
dysuria = pain upon urination
uaraemia = increased urea
What are the methods of measuring renal function and how do they work?
- Serum UREA
Also rises with dehydration - Serum CREATININE
Good general guide to renal function - eGFR – Estimated Glomerular filtration rate
Modern quick way of looking at renal function calculated from U&Es measurement - 24hr urine collection
Creatinine clearance – best measure
What is the best way to measure renal function?
eGFR – Estimated Glomerular filtration rate
What does renal failure cause?
- loss of renal excretory function
- loss of water and electrolyte balance
- loss of acid base balance
- loss of renal endocrine function (erythropoietin, calcium metabolism, renin secretion)
What are the two types of renal failure?
Acute Renal Failure
* Rapid loss of renal function
* Usually over hours or days
Chronic Renal failure
* Gradual loss of renal function
* Usually over many years
What are the pre-renal causes of failure?
- Hypoperfusion of the kidney
- shock
- Renal artery or Aorta disease
What are renal causes of failure?
- Chronic disease, drug damage, trauma, infection
What are the post renal causes of failure?
renal outflow obstruction
enlarged prostate, kidney stones, tumours
What measurement is rapid loss of renal failure measured by in ARF?
Creatinine >200μmol/L
What are the intial symptoms of ARF?
- Anuric initially (no urine) with volume overload
- Ankle oedema (if ambulatory), sacral oedema (if bed bound)
- Pulmonary oedema & breathlessness
- Raised Jugular Venous Pressure (JVP)
What are the gradual symptoms of ARF?
- Gradually progresses to polyuria
- Healing restores filtration before concentration ability
What can develop due to ARF?
- development of Hyperkalaemia (high K+)
- Can lead to cardiac arrest
- development of Uraemia and Acidosis
- High urea
- Low bicarbonate
- Increased respiratory excretion of CO2
- Raised respiratory rate
What are the causes of ARF and what is the treatment?
- Usually a PRE-RENAL cause
- USUALLY reversible with TIME
- renal support until recover
- dialysis
- nutrition
Primary/ secondary causes of CRF?
Primary (rare)
* Glomerulonephritis
* Polycystic Kidney disease
Secondary
* Diabetes (30%)
* Hypertension (20%)
* drug therapy
* Vasculitis
* Renal Artery disease/Aorta disease
Symptoms of glomerulonephritis and progression
- haematuria/proteinuria
- otherwise healthy individual
- gradual progression to:
- hypertension
- chronic renal failure
What is nephrotic syndrome?
Complication of Glomerulonephritis
* excessive loss of protein in the urine - >3g in 24hrs
* Hypoalbuminaemia
* loss of plasma oncotic pressure * tissue swelling (oedema)
What does nephrotic syndrome result in?
HYPERcoagulable state
* Loss of clotting factors – AT3 deficiency (due to hypoalbuminaemia)
* Dehydration raises other coagulation factor concentrations
What drugs cause renal disease?
NSAIDs
* inhibit glomerular blood flow
* Cause interstitial nephritis
* Avoid in renal disease if possible
Nephrotoxic drugs
* cyclosporin
What is renal vascular disease?
Reduced blood flow to the kidney
* Atheroma of renal artery/aorta
* Hypertension – narrowing of renal artery
Microangiopathy
* Immune reaction causing small blood vessel damage, RBC damage and thrombosis
* E Coli 0157
Multiple myeloma
- Plasma cell tumour
- Excess light chain production ‘clogs’ kidney
- Tubular nephritis results
Goodpasture’s syndrome
- Anti-glomerular basement membrane antibody
(anti-gbm)
Vasculitis
inflammation of blood vessels that can affect the kidney due to systemic lupus erythematosus (SLE)
What is polycystic kidney disease?
gene mutation that causes multiple cysts in the renal parenchyma
*Enlarged kidney
* Progressive destruction of normal kidney
* Gradual renal failure
What is end stage renal disease classfied as?
measurements
- eGFR <15ml/min
- Creatinine 800-1000μmol/L
How can you reduce the rate of decline?
- Eliminate nephrotoxic drugs
- Control hypertension
- Control diabetes
- Control vasculitic disease
- Steroids/other immune suppressant drugs
How can you correct fluid balance and deficiencies?
Correct Fluid Balance
* Restrict fluid intake
* Restrict salt, potassium, protein
CORRECT deficiencies
* Anaemia (erythropoietin)
* Calcium (vitamin D)
What can you remove?
- Renal stones (calculi)
- Prostate enlargement
What are the conditions caused by CRF?
- anaemia
- hypertension
- renal bone disease
- low Ca, high PO4
- hyperparathyroidism
- osteomalacia
What are the symptoms of CRF?
- polyuria
- nocturia
- tired & weak
- nausea
What are symptoms of renal disease in dentistry?
oral opportunistic infections
* Fungal and viral infections/reactivations * prone to post-op infections
dry mouth & taste disturbance
* Fluid restriction and electrolyte disturbance
bleeding tendencies
* Platelet dysfunction
renal osteodystrophy
- lamina dura lost
- bony radiolucencies
* Secondary hyperparathyroidism increases osteoclast activity
What is renal dialysis?
A PASSIVE process
* Diffusion across concentration gradients
* Allows intermittent correction of changes in plasma concentration of small molecules
* Not true ‘renal replacement’
* Significant lifestyle restrictions remain
What is haemodialysis?
blood is pumped from arteriovenous fistusa into a dialyser
in the dialyser waste products filter from the blood through an artifical membrane into a fluid called the dialysate
What is peritoneal dialysis?
implanted catheter passes fluid through peritoneal cavity and sucks it out again
How are renal endocrine components replaced?
Erythropoietin
* replaced by EPO injections
* Maintains red cell mass
Bone mass maintenance
* Vitamin D supplementation
* Osteoporosis prevention programme
Hypertension control
* Renin-angiotensin system inactive
* Ace inhibitors may have limited use
What is the optimal treatment for ESRD?
transplant
What are problems with transplant?
rejection
- acute or chronic
immunosuppression
* increased infection/malignancy risk
osteoporosis risk
What are drug interactions that occur withe dentistry after renal transplant?
Drug interactions & complications
* Prednisolone
* Cyclosporin
Steroid side effects
Increased Cancer risk
* Be suspicious of oral mucosal lesions
What should you do if patient has renal dialysis as a dentist?
treat after haemodialysis sessions
Not necessary for PD patients
liase with physicians for drugs
DO NOT use the dialysis shunt! - patient’s lifeline!
What pathogen is responsible for UTIs?
e coli
What are UTI symptoms?
- dysuria
- urinary frequency
- cloudy urine
- offensive smelling urine
- Supra-pubic pain
What can infected urine cause?
- If infected can cause:
- Cystitis
- Renal infection
- Prostate infection
Urethritis can occur in isolation
* Gonococcal
How are UTI’s diagnosised?
MSSU (urine sample)
bacteria, blood, WBCs indicative of UTI
What can cause urinary tract obstructions?
- renal calculi
- prostatic disease
- hypertrophy
- prostatic malignancy
- urinary tract strictures
- external compression
What are diseases of the prostate?
Prostatits
* Inflammation of the prostate
Benign Prostatic Hypertrophy (normal)
* Hyperplasia of the prostate
Prostatic Cancer
* adenocarcinoma
Sympotoms of urine outflow obstruction?
- Slow stream
- Hesitancy
- Frequency
- Urgency
- Nocturia
- Incomplete voiding
Treatment for BPH?
bengin prostatic hypertrophy
Initially drug based
* ⍺-blockers drugs to reduce bp
* Anticholinergic
* Diuretics
Surgery – prostatectomy
How is prostate cancer screened?
- Prostatic Specific Antigen (PSA) useful for monitoring disease activity in those known to have the disease
- mpMRI
What is treatement of prostatic malignancy?
- Surgery – radical prostatectomy
- Radiotherapy
- Hormone treatment
- Antiandrogens & LHRH analogues
What are the stone types of renal calculi and how are they treated?
- calcium and oxalate (radiopaque)
- uric acid (not radiopaque)
- treat with LITHOTRYPSY
