Kidney Flashcards
Renal Replacement Therapy (RRT)
Renal dialysis - either haemodialysis or peritoneal dialysis
Renal transplantation - either cadaveric or live donors.
End Stage Renal Failure (ESRF)
Situation where renal function has diminished to such an extent that RRT is required to sustain life.
Renal Impairment
Situation where real function is sub-optimal, but ESRF has not yet been reached.
Compromised Renal Function
All-encompassing term covering renal impairment and renal failure.
Pts with which health conditions usually have some degree of renal impairment
Diabetes mellitus
Hypertension
Diseases known to predispose to renal failure
Diabetes mellitus
Hypertension
Normal Functions of Kidney
Fluid Balance
- maintenance of water and electrolyte balance
Excretion of Waste Products
- Urea
- Creatinine
Acid-Base Balance and pH
- the major site of long-term acid-base
Endocrine Functions
- Produces: erythropoietin, renin
- Vit D metabolism
MAIN CAUSES OF RENAL IMPAIRMENT & FAILURE
Acquired Causes:
- Diabetic Nephropathy (Diabetes mellitus = leading cause of renal failure)
- Hypertensive Nephropathy
Congenital Causes:
- Autosomal Dominant Polycystic Kidney Disease (ADPKD)
RENAL IMPAIRMENT & FAILURE
Acquired Causes:
Diabetic nephropathy (small vessel disease) - Diabetes Mellitus
Hypertensive Nephropathy -Hypertension
Renovascular disease (atherosclerosis of the renal arteries)
Connective tissue diseases; especially systemic lupus erythematous
Infections such as HIV
Cancers including lymphomas, myeloma and carcinomas
Iatrogenic - many drugs may be nephrotoxic e.g. NSAIDs
RENAL IMPAIRMENT & FAILURE
Congenital Causes:
Autosomal Dominant Polycystic Kidney Disease (ADPKD)
-> formation of multiple renal cysts
Alport’s syndrome
ACUTE RENAL FAILURE =
Abrupt loss (over hours or days) or normal renal function with:
- Oligouria (urine volume <400ml/day - v.little)
- Retention of nitrogenous waste (urea) and creatinine
- Loss of normal electrolyte, water and pH homeostasis
High mortality rate ~35-80%
ACUTE RENAL FAILURE
Key Features:
- Loss of normal electrolyte and fluid homeostasis:
Kidneys lose their ability to excrete or conserve electrolytes in an appropriate way with associated disruption of fluid balance.
Hyperkalaemia (high levels of K+) results in arrhythmias (irregular heart rhythms) which can be fatal. - Metabolic acidosis
Kidneys lose their ability to maintain normal acid-base mechanism.
Acidosis associated with a high morbidity and mortality.
CHRONIC RENAL FAILURE development occurs…
CRF and associated complications develop over an extended time period.
CHRONIC RENAL FAILURE
Key Features:
Cardiovascular Disease
Anaemia
Abnormalities of Coagulation
Renal Bone Disease - Renal
Osteodystrophy
Malnutrition
Tissue Oedema
Impairment of Immune System
Malignancy
Sexual Dysfunction and Pregnancy
Mental Health Problems
Childhood Development
HOW RENAL IMPAIREMENT/FAILURE IS RECOGNISED AND MONITORED
Measurement of urea, creatinine and electrolytes in a venous blood sample = the most widely used test of renal function
Measurement of urine volumes, urine microscopy and unrinalysis = simple ways of gaining insight into renal function.
Investigations to establish a diagnosis will be guided by the suspected underlying pathology, but might include:
o Blood tests - e.g. related to DM, or auto-immune disease such as systemic lupus erythematosus.
o Imaging - ultrasound or MRI scanning e.g. if ureteric valves preventing urine flow or polycystic kidney disease are suspected
o Renal biopsy e.g. if glomerulitis suspected
