Nephrotic syndrome Flashcards
What are the functions of the following in the glomerulous?
Podocyte
Endothelial Cell
Mesangial Cell
Podocyte: They form sieve like feet (via the protein nephrin which prevents protein from getting into the urine)
Endothelial Cell: Fenestrated to allow filtration
Mesangial Cell: Contractile cell
.
What is the difference between Nephrotic Syndrome and Nephritic Syndrome?
Nephrotic
- Protein leak
- >3.5 g/d protein
- Hypoalbuminemia
- Hyperlipidemia (lipiduria)
- Pitting Edema
Nephritic
- Glomerular damage
- Decreased renal function
- RBCS
- <3.5g/d protein
- Edema
Before we get into details, list the 5 diseases that caue Primary Nephrotic Syndrome.
- Hereditary Nephrotic Syndromes
- Minimal Change Disease (MCD)
- Focal Segmental Glomerulosclerosis (FSG)
- Membranous Nephropathy (MN)
- Membranoproliferative GN (MPGN)
Hereditary Changes Force Membranous Proliferation
What are the 3 systemic diseases that cause Nephrotic Syndrome?
- Diabetes
- Amyloid Disease
- Lupus
True or False:
A disruption in the endothelial cells causes nephrotic syndrome
False:
It is damage or mutations to the podocytes.
Why might a person with Nephrotic Syndrome experience a hypercoagulable state and frequent infections?
Hypercoagulable State:
- Liver attempts to compensate for hypoalubiminemia by pushing out ALL Proteins it makes including coagulation factors
Infections:
- IgG and compliment proteins lost to urine.
A patient comes in and you diagnose him with a nephrotic syndrome. What do you prescribe him?
- Low salt diet
- Diuretics
- BP control
Children with Hereditary Neprhotic Syndrome usually have mutations in which of the following proteins?
- Laminins
- Connexins
- Podocins
- Connexons
- Nephrins
Hereditary Neprhotic Syndrome
Podocin and Nephrin
- They are key components of the Slit Diaphragm which is the sieve that filters proteins in podocyte processes.
Treatment for HNS is Kidney Transplant.
The three year old girl presents with generalized edema shortly after recovery from an upper respiratory infection. Laboratory studies reveal marked albuminuria, as well as hypoalbuminemia and hyperlipidemia. Prior similar episodes responded to adrenal steroid medication. Most likely diagnosis is:
- Hereditary Nephrotic Syndromes
- Minimal Change Disease (MCD)
- Focal Segmental Glomerulosclerosis (FSG)
- Post Streptococcal Glomerulonephritis
- Membranoproliferative GN (MPGN)
Minimal Change Disease
The key is nephrotic syndrome with resolution using steroids.
Other factors/clues underlined
True or False:
Podocytes can be antigen presenting cells.
TRUE
In 25 year old african american man presents to the emergency room with severe edema. He has a history of IV drug abuse and was recently diagnosed with HIV. Blood and urine tests reveal severe proteinuria, hypoalbuminemia, and hyperlipidemia. The patient does not respond well to a course of corticosteroids. A biopsy was performed and the histology is shown. What is the most likely diagnosis?
Focal segmental glomerulosclerosis:
- Similar presentation to MCD.
- Presents in the 20s but does not respond to corticosteroids.
- APO Lipoprotein L1 (APOL1) is associated with this in African Americans.
- Maybe associated with HIV or idiopathic
52 year old woman presents to the clinic with edema, and slightly eleveated blood pressure. She has 4+ proteinuria and microhematuria. Her past medical history is significant for lung cancer (6 months ago) and lupus. Renal biopsy shows thickening of the glomerular basement membrane, normocellularity, and granular ‘spike and dome’ immune complex deposits that are in the subepithelial regions. What is your diagnosis?
Membranous Nephropathy
- Most common cause of neprhotic syndrome and Caucasian adults
- Usually you idiopathic, but may be associated with cancer lupus (type V), hepatitis, and heavy metals (mercury)
- Characterized by a thick basement membrane, ‘spike and dome’ immune complex deposition, and subepithelial deposits
Mediated by antibodies binding to the phospholipase A2 receptor on podocytes.
A 35 year-old woman from India presents to the emergency department classical Nephrotic syndrome. We the atending heard she was from India, he asked the fellow if she used any skin creams. What was the atending thinking?
Many skin creams contain mercury in India. This could have casued her membranous nephropathy
Both membranous nephropathy and membranoproliferative glomerulonephritis (MPGN) have think glomerular basement membranes, immune complex deposition, and poor response to steroids. How do you differentiate MPGN from membranous nephropathy?
MPGN
- “Tram-track” appearance on basement membrane
- Type I associated with Hep C and HBV (in infants)
- Palpable purpura may be present
- Hypercellularity
Which type of MPGN is associated with low levels of the compliment protein C3?
Type II
