Renal Syndromes: Wall Flashcards
1
Q
What are 4 things you might use to diagnose abnormal kidney function?
A
- Changes in serum creatinine concentration
- Abnormalities in urinalysis
- Altered renal homeostatic mechanisms
- Abnormal kidney imaging studies
- NOTE: these are routine things that anyone in any office practice will have access to
2
Q
What are the important diagnostic categories of kidney disease?
A
- Acute or chronic process
- Pre-renal, intrinsic renal, or post-renal origin
- Glomerular, tubular, or vascular origin
- Inflammatory or noninflammatory process
- Associated with underlying systemic disease
3
Q
What are the 3 types of intrinsic renal disease?
A
- Glomerular syndromes
- Tubular syndromes
- Vascular syndromes
4
Q
What are 5 different categories of glomerular disorders?
A
- Nephrotic syndrome
- Nephritic syndrome
- Mixed nephritic nephrotic syndrome
- Mesangial nephritic syndrome
- Chronic glomerular disease
5
Q
What are 2 categories of tubular disease?
A
- Inflammatory tubular interstitial disease (infectious, noninfectious)
- Noninflammatory tubular interstitial disease
- Chronic interstitial disease
6
Q
What are 4 categories of vascular kidney syndromes?
A
- Prerenal azotemia
- Renal artery stenosis (unilateral or bilateral)
- Hypertensive nephrosclerosis
- Vasculitis involving the kidney
1. Typically present as nephritic syndrome
2. Reduced GFR, hematuria, proteinuria (usually in the non-nephrotic range)
7
Q
Describe nephrotic syndrome, and some of its characteristic features.
A
- Abnormal permeability of glomerular capillary wall to protein -> proteinuria/albuminuria
-
Features: proteinuria, lipiduria (may see fatty casts)
1. Typically > 3 g/day; random urinary protein to creatinine ratio >3 (spot urine)
2. 3+-4+ (highest) UA dipstick for protein
a. Dipstick urines detect albumin b/c (-) charge -> only recognizes (-) proteins
3. Low serum albumin: low oncotic pressure
4. Peripheral edema: expanded interstitial volume bc most Na, water retention there (no expansion of IV volume)
5. Typically normal GFR and normal BP - NOTE: may not have all of these things, but still have glomerular disease
8
Q
What are some clinical examples of nephrotic syndrome?
A
- Minimal change (children; 10-15% of adults) -> MCD
- Focal segmental glomerulosclerosis (a little bit more common in AA; Apo L1) -> FSGS
- Membranous glomerulopathy (most common in Caucasian) -> MN
-
Diabetic nephropathy: most common etiology of nephrotic syndrome (due to systemic disease) -> most common cause of proteinuria, CKD, etc.
1. B/c there are so many more T2D than T1D, #’s are much more prevalent in the T2 population
2. Different than other 3 b/c by the time you are overtly nephrotic, GFR is DEC and pt has HTN (others have normal GFR and BP early on)
9
Q
Is nephrotic syndrome associated with volume changes?
A
- Direct renal tubular retention of salt and water in the distal tubule -> plasmin gets filtered when there is heavy proteinuria, altering activity of ENaC
- Expanded total body sodium and total body water
- Expanded interstitial fluid volume (edema)
- Due to low serum albumin, going to favor more salt and water in the interstitial compartment (i.e., may not be ¾th, 1/4th relationship)
- Relatively normal plasma volume (normal BP)
10
Q
Nephritic syndrome basics
A
- Inflammatory changes in glomerulus -> infiltration of glomerulus by inflammatory cells
- Endothelial cell swelling
- Complement activation, often present
- Losing capillary surface area, so you are going to have a drop in GFR
11
Q
What are the urinary findings in nephritic syndrome?
A
- Hematuria (micro or gross hematuria): HALLMARK of mesangial inflammation
- Dysmorphic red blood cells in urine
- RBC casts (Tamm Horsfall) -> PATHOPNOGMONIC
- Non-nephrotic ranged proteinuria (<2 g/d or urinary protein creatinine ratio <2), 1+-2+dipstick for protein (less positive for protein than w/nephrotic syndrome)
12
Q
What are the clinical features of nephritic syndrome?
A
- HTN: retained salt and water, but they have not lost oncotic pressure (plasma volume has built up) -> pulmonary edema
- Reduced GFR (glomerular filtration rate)
- Possible gross hematuria: urine may be tea-colored or look like Coca-Cola
13
Q
What volume changes are associated with nephritic syndrome?
A
- Renal retention of salt and water: mainly because of acute reduction of GFR
- Expanded total body sodium and total body water, but still in 3/4th, 1/4th distribution
- Expanded ECFV, expansion of both EC and IC fluid spaces (depending on changes in osmolality)
1. Won’t change IC volume w/o change in osmolality - Hypertension and possible pulmonary edema
14
Q
What are some clinical examples of nephritic syndrome?
A
- Post-strep glomerulonephritis (post-infectious glomerulonephritis): prototype for a pure nephritic process
- Infection-associated glomerulonephritis
15
Q
What is the mesangial nephritic pattern? What is its hallmark?
A
- Glomerular inflammatory changes restricted to the mesangial area of the glomerulus
- Glomerular capillary wall (capillary loops) remains unaffected: ~normal GFR, minimal proteinuria
- Hallmark is hematuria (microscopic or sometimes gross hematuria)
- Red cell casts due to glomerular inflammation
