Renal Failure Flashcards
what are the normal functions of the kidneys ?
excretion of salt, water and waste products of metabolism via urine,
regulation of acid-base (H+),
regulation of blood pressure (renin),
production of erythropoietin, activation of vitamin D (1alpha OHase),
excrete water soluble drugs and metabolites
how is excretory renal function measured ?
plasma/serum creatinine,
estimated GFR, MDRD formula (sex, age, race, creatine),
creatinine clearance,
isotope GFR
what are the issues with serum/plasma creatine ?
related to muscle mass,
may not be elevated above normal range until 50% GFR lost,
changes within the normal range are significant,
artefacts - muscle damage, drugs,
serial measurements most helpful
what is the modified MDRD formula ?
eGFR (ml/min/1.73m2) = 2.107 x serum creatinine (umol/l) - 1.154 x age - 0.203 (x 0.742 if female and x 1.21 if african american
how should GFR levels from plasma creatine be interpreted ?
in the context of the individual. serial measurements most helpful
what term is sued to describe acute renal failure ?
acute kidney injury
what term is used to describe chronic renal failure ?
chronic kidney disease
what is the definition of AKI ?
rapid loss of renal excretory function over hours or days
implies reversibility if underlying condition can be successfully treated
what are the causes of pre-renal AKI ?
salt and water depletion - diarrhoea, vomiting, diuretics, fever
haemorrhage esp gastrointestinal
hypotension - heart failure, drugs, sepsis, shock
renovascular disease
what are the causes of renal AKI ?
tubular necrosis 85%
interstitial nephritis 10%
acute glomerulonephritis 5%
what are the causes of toxic AKI ?
antibiotics esp aminoglycosides and amphotercin radiographic contrast media inc non ionic chemotherapy agents esp cis platinum rhabdomyolysis intravascular haemolysis tumour lysis solvents hepatorenal syndrome
what are the causes of post renal AKI ?
obstruction to outflow from the kidneys
retroperitoneal fibrosis
neurogenic bladder
intra renal obstruction eg crystals
what is the definition of CKD ?
slowly progressive loss of excretory renal function
original cause often unknown, usually irreversible
what are the causes of CKD ?
diabetic neuropathy
genetic
vascular disease, chronic glomerulonephritis, chronic urinary outflow obstruction
what causes GFR to decline ?
increasing age
what is the presentation and symptoms of CKD ?
often asymptomatic,
symptoms emerge stage 4 or 5 (GFR
what are the consequences of AKI and CKD ?
accumulation of K+, urea, creat, H+, water, PO43-
deficiency of erythropoietin - anaemia,
deficiency of 1 alpha vitamin D3 - hypocalcaemia, hyper PTH, bone disease,
delayed drug excretion,
xerostomia,
uraemic stomatitis
what is involved in renal replacement therapy ?
erythropoietin, vit D (one-alpha), sodium bicarbonate, dialysis and transplantation
what are the consequences of immunosuppression ?
infection viral transmission with transplant malignancy hypertension dyslipidaemia osteopaemia
what are the adverse effects of cyclosporin ?
nephrotoxicity, tremor, hirsutism, gingival hypertrophy, interactions esp macrolides, dilitaizem, enzyme inhibitors, azatioprine, allopurinol
how does renal transplantation affect dental care ?
good OH essential, gingival hypertrophy, increased susceptibility to infection, antibiotic prophylaxis, drug interactions esp erythromycin
