Nephrotic Syndromes Flashcards
What is the key cell of nephrotic syndrome
Podocyte
What is nephrotic syndrome characterized by ?
(1) edema, (2) proteinuria, (3) hypoalbuminemia and (4) hyperlipidemia. It is a non-inflammatory condition with “inactive” urinary sediment (without dysmorphic red cells or red cell casts), and normal or mildly elevated creatinine
What are the characteristics of Niphritis syndrome ?
In contrast, the nephritic syndrome features (1) “active” urinary sediment (with dysmorphic red cells and red cell casts), (2) inflammation, (3) hypertension, (4) elevated creatinine and (5) crescents on biopsy in very severe forms.
What are inactive urinary sediment ?
Without dysmorphic cells or red cell casts
What are the mechanisms of Nephrotic syndrome without glomerular inflammation ?
- Podocyte Injury
- Sub-Epithelial Immune Complex Formation
- Glomerular Capillary Wall Deposition
What are the mechanisms of Nephrotic syndrome that include glomerular inflammation ?
- Mesangial or capillary wall immune complex formation and deposition including complement deposition.
- Antibodies directed against GBM
- Necrotizing Injury of the glomerular capillaries. Inflamation driven by Anti-neutrophil cytoplasmic antibodies.
Where are the immune complexes in Lupus Nephritis ?
In the subepithelial space
What is nephrotic syndrome ?
The insidious onset of Edema, Proteinureia, Hypoalbumemia and Hyperlidemia
What is an active urinary sediment ?
Red Blood Cell casts or dysmorphic red blood cells in urine suggestive of glomerular nephritis with nephritic syndrome
What is microalbuminuria ?
30-300 mg / Day of albumin in the urine, low grade proteinuria
What is nephrotic range proteinuria
> 3.5 grams / day which correlates with a urine protein / creatine ration of > 3.5
How are immune complexes trapped in the glomeruli ?
(1) the high plasma flow rate through them [with about 20% of cardiac output to the kidney], (2) high intraglomerular pressure, and (3) high glomerular hydraulic conductivity (permeability).
What determines the manifestations of the immune complex disease ?
The manifestations of disease depend on the nature of the antigen involved and the site of immune complex deposition
What will a subepithelial deposit mean ?
glomerulonephritides (such as post-streptococcal glomerulonephritis) and membranous nephropathy
What does a subepithelial deposit mean ?
Subepithelial deposits tend to cause a nephrotic syndrome picture, as seen most characteristically with membranous nephropathy.
What does a subendothelial deposit mean ?
Subendothelial and mesangial deposits tend to cause a nephritic syndrome picture as seen in focal or diffuse proliferative lupus nephritis and IgA nephropathy.
Inactive Urinary Sediment ( No dysmorphic RBC’s or RBC casts)
Nephrotic Syndrome
What is the most important clinical presentation with glomerular disease ?
Rapidly progressive glomerulonephritis with renal failure over days to weeks
What will you see in patients with renal failure secondary to glomerulonephritis ?
These patients are referred to as rapidly progressive and ggenerally have red blood cell casts in their urine due to large numbers of red blood cells clumping in renal tubules which will form cylindrical casts.
What are the 4 biggest symptons of nephrotic syndrome ?
Edema, Proteinuria, Hypoalbuminemia, and Hyperlipidemia
What are casts ? What are the most common type ?
Cylindrical formations of cells or proteinaceous material. Hyaline Casts are the most common
What will a hylane cast tell you ?
Not a whole lot. They are normal in small amounts and are common to all sorts of renal disease.
What does a granular cast mean ?
Significant renal disease
What are fatty casts associated with ?
The break down of lipid rich epithelial cells. They indicate lipiduria of nephrotic syndrome