Glomerulonephritis Flashcards
What does the combination of haematuria and proteinuria usually mean?
An underlying glomerulonephritis
(Can also happen if BP is very high)
What does glycosuria indicate?
Diabetes (which can cause a glomerulonephritis)
Pregnancy
What would you see on a dipstix in a UTI?
Leucocyturia and Nitrituria
Can also cause a little bit of haematuria (but will be accompanied by nitrituria)
What does urobilinogenuria indicate?
Haemolysis
Hepatitis, cirrhosis, liver disease
What are the anatomical parts of the kidney?
Cortex
Medulla - pyramids
Arterial and venous system
What is the functional unit of the kidney?
Glomerulus
- afferent arteriole
- efferent arteriole
- descending loop of Henle
- ascending loop of Henle
- collecting duct
- vasa recta (responsible for mainiting osmotic gradient in kidney (countercurrent mechanism))
What does the filtration barrier consist of?
Endothelium - fenestrated to allow small solutes through
Basement membrane - allows small, positively charged molecules through
Podocyte - maintains structural conformation of glomerular tuft and basement membrane components - keeps albumin etc. inside capillary system
What would you see on urine microscopy in glomerulnephritis
Red cell casts - rapidly progressive nephritic GM
White cell casts - inflammation - acute interstitial nephritis
Granular cast - acute tubular necrosis
Broad cast - nonspecific
Hyaline cast - nonspecific
Epithelial cell casts - nonspecific
Diagnostic approach in glomerulonephritis
History -> Examination -> dipstix -> microscopy -> renal function + FBC + CXR -> albumin, lipid profile, UPCR -> serology -> renal USS -> kidney biopsy
What do the findings on serology mean?
ASOT/Anti-DNAse B - post infectious GN
ANA/ds-DNA - lupus nephritis
c3/c4 - differentiates between types of nephritis
ANCAs - vasculitis
anti-GBM Ab - GBM disease
What is nephrotic syndrome?
What does it look like clinically?
Give the main causes
Injury to the filtration barrier (podocytes) -> leakage of protein
Usually slowly progressing
- Oedema, ascites, and facial swelling
- Frothy urine (proteinuria (>0.3g/24hrs), low albumin, high cholesterol)
- Hypercoagulable
- Increased propensity for infection
Causes:
Minimal change nephropathy
Focal segmental glomerular sclerosis (e.g., HIVAN)
Membranous nephropathy
Diabetic nephropathy
Amyloidosis
What is nephritic syndrome?
Give the main causes
Inflammation inside glomerulus -> breaks filtration barrier -> inflammatory cell and blood cell leakage
Causes:
Anti-GBM disease
Small vessel vasculitis (e.g., ANCA vasculitis)
Post-streptococcal glomerulonephritis
Mild proteinuria, haematuria, hypertension, oliguria, rising U and Cr
Mesangial capillary glomerulonephritis/ membranoproliferative glomerulonephritis (mix of nephrotic and nephritic)
Causes of proteinuria
Physiological:
- Fever
- Trauma
- Surgery
- Exercise
- Burns
- Conservative management
Nephrotic syndrome:
- FSGS
- Minimal change
- Diabetes
- Membranous
- Amyloidosis
- Biopsy!
Why are people with nephrotic syndrome at risk of infections?
There is podocyte fusion -> charged barrier lost -> albumin, immunoglobulins and complement lost in the urine
Why do people with nephrotic syndrome get oedema?
Primary:
Proteinuria -> hypoalbuminaemia -> low capillary colloid oncotic pressure -> decreased circulatory volume -> underfill -> compensatory Na+ and water reabsorption -> oedema
Interstitial inflammation:
Proteinuria -> Na+ and water retention -> overfill -> expanded circulatory volume -> oedema
