Pathology 1 Flashcards
What is glomerulonephritis ?
- It is a group of renal diseases which damage the glomeruli of the kidneys, other changes to the kidney are secondary
- It’s often caused by your immune system attacking healthy body tissue.
What are the key pathological features of glomerulonephritis in general ?
- Immune complexes are deposited in the glomerular capillaries
- Glomerular subendothelial immune complexes damage the glomerulus due to them activating the complement system etc
- It is usually diffuse but can sometimes be focal
What are the key 3 key histological features of glomerulonephritis in general?
- Hypercellularity = an increase in the number of glomerular cells
- Thickening of the the glomerular capillary wall
- Crescent formation - crescent shaped mass of cells that compress the glomerular tuft
What are the general signs/symptoms of glomerulonephritis ?
- Hematuria
- Proteinuria
- High BP - hypertension
- Fluid retention oedema
Define what is meant by nephrotic syndrome and what are the signs of it ?
Nephrotic syndrome is a condition which can be caused by a number of renal diseases. It causes swelling of body tissues and increases the chances of infection.
It is characterised by a triad of:
- Proteinuria (> 3g/24hr) causing
- Hypoalbuminaemia (< 30g/L) and
- Oedema
What is minimal change nephropathy and what are its signs/symptoms ?
- It is the most common cause of nephrotic syndrome in children, although can occur in adults
- On light microscopy glomeruli look normal (hence minimal change), on electron microscopy there is loss of normal glomerular epithelial foot processes (podocytes)
- Oedema and proteinuria occur
Describe the key features of diffuse membranous glomerulonephritis
- Diffuse hyaline thickening of the walls of ALL the glomerular capillaries (hence diffuse)
- Immunofluroescence staining shows immune complexes on the capillary walls and IgG deposited
What are the key features of mesangiocapillary (membranoproliferative) glomerulonephritis ?
Characterised by hypercellularity and capillary wall thickening
What is the key features of focal glomerulonephritis?
- It is focal so only affects a proportion of the glomeruli
- Glomerular lesion consitis of a cellular proliferation probably of mesangial cells
- Has characteristic mesangial deposition of IGA on immunofluroscence
What is glomerulosclerosis ?
It is hardening of the glomerulus of the kidneys, which is the general term to describe scarring of the kidneys tiny blood vessels
What are some of the conditions associated with glomerulonephritis ?
- SLE
- Henoch shonlein purpura - the IGA deposits in the kidneys due to this disease
- Goodpastures - this is thought of as a disease which causes both kidney failure and pulmonary haemorrhage (affects both the kidneys and lungs)
What is pylonephritis ?
- It is inflammation of the renal pelvis, calyces and parenchyma (part which produces urine)
- The renal pelvis is affected first
- It is usually focal in distrubution and can be acute of chronic
How does pylonephiritis usually occur ?
- Usually due to ascending infection - often associated with vesicoureteric reflux, urinary tract obstruction and diabetes
- Cystitis is often present (as this is lower down in the bladder)
What is the most common organism for causing pylonephritis?
E.coli
What are the risk factors for the development of pylonephritis ?
- Urinary Tract Obstruction; e.g. Calculus, stricture, neoplasm, congenital anomaly (e.g. duplex systems), prostatic and urethral pathology.
- Vesico-ureteric reflux (VUR)
- Diabetes.
- Females (shorter, wider urethra)
- Pregnancy; Ureteric dilatation – stasis due to hormonal and anatomical effects.
- Instrumentation - e.g. catheter
Define chronic pylonephritis and what are the classic features of it
- This is recurrent or long-lasting episodes of pylonephritis
- Causing progressive scarring
- Seen radiologically as asymmetrical shrinkage of the kidney, irregularity of the renal outlet due to cortical scarring and dilatation or disturbances of calyces adjacent to the scarred areas
- Signs are large volume or urine, Hypertension and/or Uraemia.
- Often no history of UTI
