renal pathogy - nephrotic syndrome

renal pathogy - nephrotic syndrome

"1700 L of blood filtered per day = 1 L urine"
180 L/day  (not 1700 L)  volume filtered with GFR = 125 ml/min

immunecomplex deposits may be anywhere in glomerulus 

podocytes

Glomerulus

capillaries = open?
mesangial cells - nl cellularity?
capillary loops nl or thickened?

Glomerular diseases

• Significant cause of pathology: chronic glomerulonephritis is one of the most common 

causes of chronic renal failure

• May be primary i.e. Kidney is the only/predominant organ affected (e.g. minimal change disease, focal segmental glomerulosclerosis, IgA nephropathy)

• May be secondary to systemic conditions (e.g. SLE, diabetes, hypertension)

• The kidney is similar to other organs: it only has a limited number of ways to respond to injury:

Glomerular diseases: clinical manifestations

• Nephrotic syndrome

• Nephritic syndrome (hematuria, azotemia, variable proteinuria, oliguria, edema, hypertension)

• Rapidly progressive glomerulonephritis (Acute nephritis, proteinuria, acute renal failure)

• Asymptomatic hematuria or proteinuria (Glomerular hematuria; subnephrotic range proteinuria)

• Chronic renal failure (Azotemia  uremia progressing for years)

Nephrotic Syndrome

Defined as:
Marked proteinuria with excretion of: 
> 3.5 gm protein/24 hours 
Hypoalbuminemia
Hypercholesterolemia 
 Edema


Minimal change disease: etiology
• No immune deposits, but several features point to an immune etiology
– Clinical association with respiratory infection, prophylactic immunization
– Response to corticosteroids, other immunosuppressants
• Current hypothesis:
– Some immune dysfunction with elaboration of a cytokine that damages visceral epithelial cells: electron microscopy points to primary visceral epithelial cell (podocyte) injury
• Not all immune mediated
– Nephrin mutation can lead to a congenital nephrotic syndrome (Finnish) like MCD

Focal segmental glomerular sclerosis

does not do as well as Minimal Change Disease

can progress to end stage renal disease = need transplant

can occur within hours of receiving new kidney (circulating factor)