Renal Disease Flashcards
Anatomy of a nephron
- Afferent arteriole enters the glomerulus in the Bowman’s capsule
- Primary convoluted tubule
- Loop of Henle dipping into the renal medulla
- Descending limb and ascending limb of loop of Henle
- Distal convoluted tubule
- Collecting duct leading to the pelvis of the kidney
Functions of the kidney
- Excrete waste including drugs/metabolites
- Regulate fluid volume
- Regulate acid/base
- Maintenance of blood pressure
- Excrete nitrogenous waste
- Synthesis erythropoietin/renin/1,25 cholecalciferol
- Target organ for parathyroid hormone/aldosterone/ADH
Normal kidney functions values
- Filter 100ml/min
- 99% of the 100ml is reabsorbed
- Urine production of 1ml/minute
How is GFR estimated
-Glomerular filtrate rate (GFR) is estimated from blood creatine levels, age, race and sex
Classification of kidney disease
- Acute renal failure (declining over hours/days): unlikely to see this in clinic
- Chronic kidney disease (two samples taken 90 days apart)
- Pre-renal
- Renal
- Post-renal
Kidney disease classification in terms of where the problem is and likely causes of each
1) Pre-renal
Perhaps hypertensive renal artery stenosis
2) Renal
3) Post-renal
Perhaps due to obstruction via a stone
Causes of kidney disease
- Type 2 diabetes (many have associated renal disease)
- Hypertension
- Glomerular nephritis (IgA nephropathy)
- Polycystic kidney disease (1:1500)
- Vasculitic disease of the kidney
- Kidney infection
- Outflow obstruction/reflex
Clinical features of kidney disease
Often insidious (may not notice until the kidney fails)
- Loss of appetite
- Fatigue/lassitude
- Headaches
- Itching
- Nausea
- Weight loss
- Pain in back
Stages of kidney disease and GFRs relating to disease
-A normal GFR is 100
GFR>60 Stage 1 and 2
GFR 30-59 Stage 3
GFR<30 Stage 4 and 5
If less than 10 then look at transplant or dialysis
Stages of increasing severity of kidney disease
- GFR decrease
- Haematurea (blood in urea)
- PRoteinurea (protein in urea)
- Structural abnormalities
- Genetic disorder
Consequences of kidney disease
- Increased cardiovascular risk (often already diabetic/hypertensive)
- Anaemia and reduced immunity as erythropoetin synthesis is affected
- Increased risk of bleeding
- Decreased bone health due to calcium loss
- Build up of toxins
- Reduced drug excretion
Treatment of kidney disease
- Lifestyle treatment
- Stop smoking
- Low fat/cholesterol foods
- Low salt/potassium intake
- Exercise
- Protein restriction
- Fluid restriction
-Treat the underlying cause if possible
- Control blood pressure (ACE inhibitors, Angiotensin II receptor blockers)
- Control anaemia (transfusions/iron supplementary/EPO)
- Control blood glucose
- Maintain bone health (vitamin D/calcium)
- Lower cholesterol (statins)
Dental Implications of people with kidney disease
- Take care with stage 4 and 5 GFR<30
- Increased peridontal disease (may be related to diabetes)
- Oral signs of anaemia
- Bone abnormalities
- Potential increased bleeding tendency
- Avoid NSAIDs/erythromycin
- Reduce dose of renal exreted drugs eg. amoxycillin
- Good oral health supports nutrition/preparation for transplant
Bone changes in chronic kidney disease
- Massive radioleuncy seen on a PA?
- Check PTH levels
- Could be a giant cell carcinoma
- Increase in PTH as more calcium is lost in the urine
- Releases calcium from skeleton by activation of osteoclast
- OCs can group together and begin resorbing bone forming a central giant cell carcinoma
- Often occur on their own but sometimes secondary to renal disease
Common dental drugs and chronic kidney disease affect
Lignocaine- No alteration Articaine- No alteration Amoxycillin- Reduce the dose if GFR <10 NSAIDs- Avoid if GFR <10 or diabetes Erythromycin- Avoid due to drug interactions Midazolam- Use with caution if GFR<30
When do you use dialysis and what are the two types of dialysis
Necessary once function no longer able to meet demand
GFR<10
1) Haemodialysis
2) Peritoneal Dialysis
Haemodialysis how many times a week, where, requirements
- 3 time a week
- Requires an AV fistula for vascular access (stay tf away from this. not even BP cuff)
- Requires dialysis machine
- Can be done at home
- Requires anticoagulation with heparin
Peritoneal Dialysis types
- Continuous ambulatory peritoneal dialysis
- Continuous cycler assisted peritoneal dialysis
Peritoneal dialysis features, requirements, risk, contraindications and how often
- More flexible as no machine
- Requires skilled/dextrous patient/meticulius
- Risk of peritoneal infection
- Has to be done frequently
- May not be suitable if abdominal trauma, surgery
Dental Implications of something not sure
-Look on slide 33 doesnt make sense
Dental Implications of haemodialysis
- Treatment on morning of non-dialysis days
- Local haemostatic measures if surgery
- Antibiotic prophylaxis due to immune defect
- Liase with renal team
- Avoid injections/BP measurement AVF arm
Kidney transplant benefits, success and requirements
- Very successful
- Cost effective
- Psysiological beenfit
- Live donor
- Requires immune suppression for life but patients no longer tied to a machine
Post Graft Care
Two phases
1) Early post operative (prevent acute rejection, optimise graft function, prevent opportunistic infection)
2) Later phase (preserve graft function and prevent long term consequences of immune suppression)
Consequences of immune suppression
Malignancy
Infection
Premature cardiovascular disease
Immune suppression drugs and oral relevance
Cyclosporin
- Poor wound healing
- Gingival hyperplasia
Tacrolimus
- Less gingival hyperplasia
- Oral ulceration
- Perioral numbness/tingling
Azathioprin
- Stomatitis
- Opportunistic oral infection
Micofenalate
-Decreased white cell count
Corticosteroids
- Oral infection
- Poor wound healing
Serolimus
-Oral ulcers
Graft versus host disease
- Occurs in stem cell transplant patients
- Oral components
- Mucosa lichenoid changes, erythema, ulceration, hyperkerotitic patches, mucosal atrophy
- Muculoskeletol decreased mouth opening and limited tongue mobility
- Salivary gland dysfunction due to fibrosis/inflammation
