High Yield Topics-Renal Flashcards
Normal values of pH, HCO3, and CO2 and their relationship
pH = 7.4 HCO3 = 24 CO2 = 40
pH = HCO3/CO2 pH = metabolic/respiratory
Describe steps to determine primary deficit with compensatory MOA for acid/base problems
- Determine acidosis or alkalosis to given pH, HCO3, and CO2
- Matching = Primary deficit
- What’s left = compensatory MOA
Determine primary deficit with compensation for this example.
pH = 7.31 HCO3 = 18 CO2 = 28
pH = 7.31 --> acidosis HCO3 = 18 --> metabolic acidosis CO2 = 28 --> respiratory alkalosis
- Metabolic acidosis w/ compensatory respiratory alkalosis
(Normal/Elevated) anion gap is due to loss of HCO3
Normal
(Normal/Elevated) anion gap is due to the presence of extra external acid (HCO3 is used to buffer the aci)
Elevated
Equation to determine compensation for metabolic acidosis
Winter’s formula:
Expected Pco2=1.5[HCO3-]+8 +/-2
In normal anion gap metabolic acidosis, if expected Pco2 > actual Pco2, then there is too little Pco2.
You have a “concomitant” respiratory
alkalosis
In normal metabolic acidosis, if expected Pco2 < actual Pco2, then there is too much Pco2.
You have a “concomitant” respiratory
acidosis
Diarrhea, renal tubular acidosis, and saline infusion are common causes of what acid-base disturbance?
Normal anion gap metabolic acidosis
Lactic acidosis, diabetic ketoacidosis, renal failure (uremia), and toxicities (methanol, ethylene glycol, salicylates) are common causes of what acid-base disturbance?
Elevated anion gap metabolic acidosis
Equation to check anion gap
AG = Na+ - (Cl- + HCO3-)
- AG = 8-12 –> Normal AG
- AG > 12 –> ↑AG
Glomerular disease caused by destruction of GBM negative charge and podocyte effacement (thinning) leading to protein leakage (proteinuria >3.5 g/day)
Nephrotic syndrome
Which nephrotic syndrome is described by the following:
Common in children after recent infection/immunization; Corticosteroids for tx
Minimal change disease
Normal histology on “LM” and podocyte effacement & fusion on EM are findings of
Minimal change disease
Which nephrotic syndrome is described by the following:
Common in AA and hispanics; caused by idiopathic, viral infections (HIV/Hepatitis), heroin abuse, or other conditions (sickle cell, obesity)
Focal Segmental Glomerulosclerosis
Segmental sclerosis and hyalinosis, podocyte effacement & fusion is Histology/LM/EM findings of
Focal Segmental Glomerulosclerosis
Which nephrotic syndrome is described by the following:
Primary cause is by auto-antibodies against “phospholipase A2” receptors on GBM
Membranous nephropathy
Which nephrotic syndrome is described by the following:
Secondary cause is by Drugs (NSAIDs, penicillamine), SLE, Cancer, and viral infections (Hepatitis)
Membranous nephropathy
Capillary loop thickening and GBM thickening on LM; granular IF; subepithelial deposits of immune complexes (“spike and dome” appearance) on EM are findings of
Membranous nephropathy
Which nephrotic syndrome is described by the following:
Amyloid deposits in mesangium (early) –> endothelium (late)
Amyloidosis
+ Congo red and apple green birefringence is Histology/LM/EM findings of
Amyloidosis
What organ is the most commonly involved organ of Amyloidosis?
Kidney
Which nephrotic syndrome is described by the following:
Most common cause ESRD in the US; caused by diabetes
Diabetic glomerulonephropathy
Mesangial expansion and “nodular” glomerulosclerosis (Kimmenstiel-Wilson nodules) is Histology/LM/EM findings of
Diabetic glomerulonephropathy
Glomerular disease caused by “inflammation” (lymphocytes are involved); present with hematuria, dysmorphic RBCs, RBC casts, and WBC casts in urine
Nephritic syndrome
Which nephritic syndrome is described by the following:
“2-4 weeks” after group A strep infection of pharyngitis or skin rash (impetigo); caused by type III (immune complex deposition) hypersensitivity; presents with periorbital edema, hypertension, and cola-colored urine
Poststreptococcal glomerulonephritis
granular (IgG, IgM, c3) IF in mesangium and GBM; subendothelial and subepithelial (GBM) immune complex deposition on LM are findings of
Poststreptococcal glomerulonephritis
Which nephritic syndrome is described by the following:
Caused by SLE
Diffuse proliferative glomerulonephiritis
“wire looping” (neutrophilic infiltration) of capillaries; granular IF; subendothelial immune complex deposition on EM is Histology/LM/EM findings of
Diffuse proliferative glomerulonephiritis
Which nephritic syndrome is described by the following:
Caused by hepatitis infection or idiopathic; subendothelial immune-complex deposition; granular IF
Type I Membranoproliferative glomerulonephiritis
Which nephritic syndrome is described by the following:
Caused by C3 nephritic factor (IgG autoantibody that overactivates complement activation); immune-complex deposition intramembranously; “tram-tracking” or GBM splitting on H&E or PAS stains
Type II Membranoproliferative glomerulonephiritis
aka. dense deposit disease
What kidney diseases are considered both nephrotic and nephritic syndromes?
Diffuse proliferative glomerulonephiritis & Membranoproliferative glomerulonephiritis
Which nephritic syndrome is described by the following:
rapidly deteriorating renal function; includes several diseases that show this pattern
Rapidly progressive glomerulonephiritis
Which nephritic syndrome is described by the following:
RPGN that shows “LINEAR” IF due to antibodies against type IV collagen on GBM and alveolar BM –> hematuria & hemoptysis
Goodpasture syndrome
Which nephritic syndrome is described by the following:
RPGN that is pauci-immune (no Ig/c3 deposition); negative IF but + C-ANCA
Granulomatosis with polyangiitis (aka. WeCner’s syndrome)
Which nephritic syndrome is described by the following:
RPGN that is pauci-immune (no Ig/c3 deposition); negative IF but + P-ANCA (2)
Microscopic polyangiitis
OR
Eosinophilic Granulomatosis with polyangiitis (aka. Churg-Strauss)
PSGN and DPGN can rapidly deteriorate renal function leading to
Rapidly progressive glomerulonephiritis
Unique LM finding of RPGN
Crescent (fibrin) formation in glomerulus
- crescent is made of fibrin + proliferation of cells (macrophages, fibroblasts, etc.)
Which nephritic syndrome is described by the following:
Occurs a few days (2-5) after URI or GI tract infection –> IgA immune complex deposition in mesangium; “mesangial” proliferation and granular IgA immune complex on IF
IgA nephropathy
aka. Berger Disease
Vasculitis associated with IgA nephropathy; cause non-blanching palpable purpura
IgA vasculitis
aka. Henoch Schonlein Purpura
Which nephritic syndrome is described by the following:
Caused by mutation in type IV collagen –> thinning and splitting of GBM; present with triad (eye problem, hearing loss, and kidney problem)
Alport syndrome
*STUDY AID: Albert can’t pee, can’t see, can’t hear a bee
“basket weave” with thinning and splitting of GBM is Histology/LM/EM findings of
Alport syndrome
What is the complement level finding in nephritic syndrome?
C3 will be low due to activation of complement by immune complex –> deposition –> low serum C3 level
You will see WBC casts in urine only in what glomerular disease?
Nephritic syndrome
What kidney-related disorder can present with UNILATERAL flank tenderness, colicky pain radiating to groin, and hematuria?
Kidney stones
the most common reason for Ca (Ca oxalate and Ca PO4) kidney stones in adults; caused by ↑ GI absorption, ↑ mobilization of Ca from bone, or ↓ renal tubular Ca reabsorption
Hypercalciuria
Serum Ca+2 level in hypercalciuria is
normocalcemic
- due to regulation of plasma Ca levels by vitamin D and PTH
Explain how hypocitraturia can increase formation of Ca-oxalate nephrolithiasis?
When citrate level is normal in urine, Ca+2 binds with citrate and forms a soluble calculi. When citrate level in urine decreases or Ca+2 excretion increases, calcium will bind to oxalate (or phosphate) and form an insoluble calculi