Kidney and Renal Disease Flashcards
What are the main functions of the kidneys
- Filter 180L fluid daily
- Clear waste
- Balance acid/waste
Production of hormones: Control blood pressure (renin)
Help to make blood (erythropoietin)
Regulate bone health (Ca, P) (Vit. D).
What is creatinine?
- End product of skeletal muscle catabolism
- Dietary meat intake can increase creatinine
- Released into the circulation at a constant rate
- Creatinine is freely filtered into the glomerulus
- 15% of urinary creatinine is secreted by the tubules
- Used to calculate Glomerular Filtration Rate
How to calculate the GFR
- Cannot measure directly. Need to measure creatinine and creatinine clearance (ml/min)
- GFR declines with ageing
- GFR varies inversely with reciprocal of plasma creatinine (1/Pcr)
What are the different types of Kidney Dysfunction
- ) SALT & WATER HOMEOSTASIS
- Changes in total body water
- Changes in blood pressure
- Changes in urine volume or concentration - ) EXCRETION OF WASTE PRODUCTS
- Uraemia
- Acidosis e.g. lactic acid, ketoacids
- Others: Potassium, Phosphate, Uric acid
- Clearance of drugs
Kidney Function Dysfunction continued…
- ) HUMORAL DISTURBANCE:
- Anaemia
- Renal bone disease
- Hypertension - ) BARRIER FAILURE
- Haematuria
- Proteinuria
- Lipiduria
How do we treat chronic kidney disease
- ) MILD/MODERATE:
- Diet/Fluid balance
- Supplements - Alkali, Vitamin D, Iron
- Drugs - Phosphate, Hypertension, Anaemia
specific conditions - immunosuppression
- ) SEVERE:
- Dialysis
- Transplantation
3.) VERY SEVERE: Kidney replacement treatment: - Peritoneal Dialysis - Haemodialysis - Transplant
What is Cystitis?
Infection of the bladder:
- Dysuria, urinary frequency, urgency, suprapubic pain +- haematuria
What is Pyelonephritis?
Infection of the kidney
- Cystitis + systemic features (fever, flank pain)
Test - Urinalysis, urine culture (E.coli, proteus/klebsiella)
Men - prostatitis (different if recurrent)
Risk factors: sexual intercourse, immunosuppression, diabetes, urinary tract obstruction
What are the renal causes of hypertension?
- Reno vascular disease (asymmetry on u/s, symptoms)
- Fibromuscular disease
- Any cause of acute or chronic kidney disease
(clue: increased creatinine, blood/proteinuria) - Polycystic kidney disease
- Glomerulonephritis: IgA nephropathy
- Post renal transplant - medication
What is Renovascular disease?
A progressive condition that causes narrowing or blockage of the renal arteries or veins (blood vessels that take blood to and from kidneys)
What is Fibromuscular dysplasia?
Non-atherosclerotic, non-inflammatory disease of the blood vessels that causes abnormal growth within the wall of an artery
- Arterial stenosis, arterial occlusion aneurysm.
What is Polycystic Kidney Disease?
- Autosomal dominant inheritance
- 1 in 400-1000 (world)
- Gradual progressive decline in kidney function
- ESRF in -50% by 60yrs
- Marked clinical variability
- Earliest features include hypertension, UTIs
- polycystic livers
- Intracranial aneurysms
What is Glomerulonephritis?
Inflammation of glomeruli - filtering units kidney
Clues - active urinary sediment (blood/proteinuria)
- Dysmorphic red cells - red cell cast
Various causes - Age and presentation help differentiate diagnosis:
- Nephritic syndrome
- Nephrotic syndrome
What is Nephrotic Syndrome?
A collection of symptoms due to kidney damage
- Heavy proteinuria
- Low albumin
- Peripheral Oedema
And possibly…
- Thrombosis - DVT, PTE
- Hyperlipidaemia
Normal creatinine
- Acute tubular necrosis - older patients
- Acute interstitial nephritis - drug reaction (minimal change)
- Myeloma
CAUSES - IDENTIFY ON RENAL BIOPSY DEFINITIVELY:
- Focal segmental Glomerulosclerosis (FSGS)
- Membranous
- Diabetes
- Minimal change
- Amyloid
What is Nephritic Syndrome?
Combination of:
- URINALYSIS:
- OLIGURIC AKI
- HYPERTENSION
- OEDEMA +-
Standard investigations:
- Blood test
- Renal biopsy
Most commonly caused by Acute Glomerulonephritis
Crescentic Glomerulonephritis:
- Assoc. systemic symptoms: fevers, weight loss
- Upper/resp tract symptoms, rash
