Renal Diseases (2)
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Transcript of Renal Diseases (2)
Renal disorders and Transplantation
Dr. Oluyori Adegun Clinical and Diagnostic Oral Sciences
Learning Outcomes (pg.26)
• By the end of this session you should:
• Recognise the signs and symptoms of renal and renal tract diseases their causes and the consequences of renal failure
• Have knowledge of renal replacement therapies
• Be able to recognise the peripheral signs of renal disease including oedema and dehydration jaundice
• Be able to explain the dental relevance of renal diseases and their management
Renal Functions
• Specialised functions of the kidney include
• Excretion of many metabolites and drugs
• Regulation of normal body fluid volumes and electrolyte balance
• Regulation of acid-base balance
• Endocrine functions
Body Fluid and Electrolyte Balance
• Kidneys receive ~ 25% of blood volume per minute
• Made up of nephrons where
filtration of small molecules and ions
from blood occurs
• Through selective reabsorption
it reclaims useful materials such as glucose, amino acids etc
• The kidneys constantly pass urine through the ureter →bladder→ urethra
Body fluid and Electrolyte Balance
• Proximal convoluted tubule • Actively reabsorbs glucose, amino acids, uric acid and
inorganic salts • Active transports out of Na controlled by Angiotensin II • Active transport of phosphate suppressed by PTH • Water follows by osmosis
• Loop of Henle • Water continues to leave by osmosis
• Distal convoluted tubule • More Na is reabsorbed by active transport and still more
water follows by osmosis
• Collecting tubule • Final adjustment of body Na and water content (ADH&
Aldosterone)
Endocrine Functions
• Renin Production
Endocrine Functions
• Erythropoietin Production
Endocrine Functions • Hydroxycholecaciferol (active vitamin D) Synthesis
• Prostaglandin Synthesis
Renal Diseases • Acute Renal Failure
• Pre-renal factors
• Hypotension- Haemorrhage/severe burns
• Renal thrombosis
• Sepsis
• Drugs causing renal shutdown (NSAIDs and ACE inhibitors)
• Renal factors
• Antibiotics – Gentamicin, Amphotercin
• Analgesic overdose – Aspirin and other NSAIDs, Paracetamol
• Multiple organ failures
• Interstitial nephritis etc
• Post renal factors
• Obstructed urine flow
• Medical emergency, leads to confusion, seizures and coma unlikely to be seen in primary dental care
Chronic Renal Disease (CRD)
• Not a specific disease as there are several causes
• Characterised by the presence of kidney damage or reduction in GFR (< 90ml/min) for 3 or more months
• Resulting in a progressive loss of renal function through 5 stages (Early, Mild, Moderate, Severe and End-stage renal failure)
• Normal GFR Male -130ml/min, Female- 120ml/min
• Common Causes of CRD include:
• Long standing Hypertension
• Diabetes Mellitus
• Chronic pyelonephritis
• Chronic glomerulonephritis
• Polycystic renal disease
• Urinary tract obstruction
• Renal artery stenosis
Chronic Renal Disease
• Less common causes include:
• Systemic Lupus Erythematosus
• Amyloid
• Multiple Myeloma
• Gout
• Lead poisoning
• Longterm use of drugs
• Analgesics,
• Gold,
• Penicillamine,
• Cyclosporine
• Clinical Features • Symptomless at first
• Symptoms manifest when Kidney function drops below 25% • Blood and immune
• Anaemia (toxic suppression of bone marrow/ ↓erythropoietin)
• Purpura/ bleeding tendency (Abnormal platelet production/ defective vWF, ↓Thromboxane)
• Lymphopenia- liability to infections
• Gastrointestinal • Anorexia
• Nausea and vomiting
• Metabolic • ↑Nitrogenous compounds (Azotaemia/Uraemia)
• Renal osteodystrophy ( Phosphate retention →↓ plasma calcium → ↑PTH activity (Secondary hyperparathyroidism)
• Deficiency of active viatmin D), Polyuria, Polydipisia, Glycosuria
Chronic Renal Disease
Chronic Renal Disease • Neuromuscular
• Headaches
• Confusion
• Sensory disturbances
• Tremors
• Peripheral neuropathy
• Cardiovascular • Hypertension
• Congestive cardiac failure
• Atheroma
• Peripheral vascular disease
• Skin • Pruritus
• Bruising
• Infections
Investigations • Urine examination – red cell casts, white cell casts, urate crystals
• FBC
• ↓RBC- Anaemia,
• Impaired platelet function→↑ Bleeding time
• Biochemistry
• ↑Urea and creatinine
• ↑potassium and metabolic acidosis
• ↑ phosphate→↓ Calcium→↑ PTH
• Renal ultrasound – ? renal size ? renal obstruction
• Renal Biopsy
General Management
• Treatment goal is to slow down or halt the progression of the disease to end-stage renal failure
• Anaemia→Erythropoietin (Epoietin)
• Hypertension→ACE inhibitors e.g. Captopril
• Fluid retention→ Diuretics
• Hyperphosphataemia→ Calcium carbonate
• Hypocalcemia→ Calcium supplements/Vitamin D3
• Metabolic acidosis→ Sodium bicarbonate
• High cardiovascular risk → Aspirin, Statins, smoking
cessation
Drug Modifications in CRF
Usually safe Dose change (severe RF) Dose reduction (mild RF) Avoid
Antimicrobial Doxycycline
Minocycline
Cloxacillin
Flucloxacillin
Rifampcin
Ampicillin
Amoxycillin
Benzylpenicillin
Clindamycin
Erythromycin
Metronidazole
Co-trimoxazole
Systemic Aciclovir
Cephalosporin
Ciprofloxacin
Vancomycin
Gentamicin
Tetracyclines
Aminoglycosides
Cefixime
Anaesthetics Lidocaine Prilocaine
Atricaine
Analgesics Paracetamol Codeine Aspirin
NSAIDs
Anticonvulsant/Sedatives
Diazepam
Midazolam
Carbamazepine
Lamotrigine
Renal Replacement therapy
• Renal dialysis (removes metabolites and excess water) • Indicated in end stage renal failure
• Two types
• Peritoneal dialysis
• Peritoneal membrane acts as natural semi-permeable membrane
• Less efficient haemodialysis but can be carried out more frequently
• Relatively easy and can be done at home
• Can be travelled with (Continuous ambulatory peritoneal dialysis)
• Haemodialysis
• Vascular access for introduction of infusion lines (Arteriovenous fistula)
• Patient dialysed 3 times a week for 3 hours each session
Peritoneal Dialysis
Haemodialysis
Renal Replacement Therapy
• Renal transplantation
• Indicated in medically suitable patients with end stage renal disease
• Is the treatment modality of choice in children and patients with diabetic nephropathy
• Transplanted kidney is usually sited in the right iliac fossa
• Transplant recipients require lifelong immunosuppression (Ciclosporin, Azathioprine, Corticosteroids) to prevent autograft rejection
• Complications • Transplant rejection
• Immunosuppression induced infection or malignancy
• Increased risk of ischaemic heart disease
Dental Relevance (CRF) • Dental treatment is best suited for the day after dialysis (Heparin effect worn off
and for maximal benefit from dialysis)
• Ensure careful haemostasis during surgical procedures
• Haemodialysis can prediposes to blood borne virus (Hepatitis B &C)
• Odontogenic infection should be treated vigorously
• Prescription of drugs excreted mainly by the kidney needs to be adjusted post consultation with a renal physician
• Avoid systemic fluorides
• Avoid aspirin and NSAIDs
• Local anaesthesia is safe unless there is severe bleeding tendency
Dental Relevance (CRF)
• For intravenous cannulation and taking blood
• Avoid arteriovenous fistulas arm to minimise the risk of
• Fistula infection
• Thrombophlebitis
• Renal osteodystrophy- 2o to Hyperparathyroidism
• Loss of lamina dura on intraoral radiographs
• Brown tumours on ginigiva
• Osteomalacia
Dental Relevance (Renal transplantation)
• Patients taking steroids may need steroid cover for stressful procedures
• Transplant patients on immunosuppressants more susceptible to infection (e.g. oral candidiasis) – complete dental treatment before transplant if possible
• Transplant patients must carefully monitored and aggressively treated for infections
• Cyclosporine-↑risk of gingival hyperplasia
• ↑ed risk of tuberculosis
Nephrotic Syndrome • Glomerular damage resulting in
• Massive protienuria,
• Hypoalbuminaemia,
• Hypercholesterolaemia
• Clinical features & Dental Relevance • Facial oedema, ascites
• Prediposed to infections with Streptococcus pneumonia & Haemophilius influenzae – loss of IgG in urine
• Loss of cholecalciferol binding protein → Vitamin D def.
• Loss of antithrombin III and increased clotting factors→ Hypercoagulability → Thrombosis
• Longterm corticosteroid therapy is also problem
Any Questions?