Renal Flashcards
In metabolic acidosis there is increased urinary excretion of which substances?
H+, NH4+, and H2PO4-
What happens to the concentrations of PAH, creatinine, inulin, and urea as fluid runs along the proximal tubule?
They increase
What happens to the concentrations of bicarb, glucose, and amino acids as fluid runs along the proximal tubule?
They decrease
How does CKD with mineral bone disease present?
Hyperphosphatemia, secondary hyperparathyroidism, and decreased calcitriol levels. Pts can be asymptomatic or develop weakness, bone pain, and fractures
Vasopressin and Desmopressin cause increased permeability of which substances?
Increase in water and urea permeability at the inner medullary collecting duct
Filtration fraction equation
FF=GFR/RPF
What is responsible for the thrombotic and thromboembolic complications of nephrotic syndrome?
Loss of anticoagulant factors, especially antithrombin III
Linear deposits of immunoglobulin along the glomerular basement membrane
anti-glomerular basement membrane disease
What are the immunoglobulin deposits composed of in anti-glomerular membrane disease
IgG and C3
What is seen on light microscopy in anti-GBM disease?
Glomerular crescents composed of proliferating parietal cells with an infiltration of monocytes and macrophages
Renal failure and pulmonary hemorrhage in patients with anti-GBM antibodies
Goodpasture syndrome
Immunofluorescence microscopy in poststreptococcal glomerulonephritis
Granular deposits of IgG, IgM and C3 in the mesangium and basement membranes
Membranous glomerulonephropathy
A cause of nephrotic syndrome. Can occur secondary to underlying malignant tumors, infections, and certain meds.
Findings on imaging with membranous glomerulopathy
Diffuse increased thickness of the glomerular basement membrane on light microscopy, spike and dome appearance on methenamine silver stain, and granular deposits on immunofluorescence
Presentation of minimal change disease
Weight gain, pitting edema, significant proteinuria, hypoalbuminemia, hyperlipidemia
Findings in minimal change disease
Biopsy specimen will show no obvious glomerular lesions on light microscopy and will be negative for immune deposits on immunofluorescence. Electron microscopy shows effacement of the foot processes supporting the epithelial podocytes with weakening of slit-pore membranes
What other conditions are associated with ADPKD?
Berry aneurysms, hepatic cysts, mitral valve prolapse
Urine findings in acute tubular necrosis
Brown, granular casts
Which parts of the kidney are particularly susceptible to ischemia?
Proximal tubule and medullary segment of thick ascending limb
Which part of the kidney is susceptible to nephrotoxic ATN?
Proximal tubule
What are key causes of acute interstitial nephritis?
NSAIDs, PCN, diuretics
Oliguria, fever, and rash days to weeks after starting a new drug. Eosinophils found in the urine
Acute interstitial nephritis
Presentation of renal papillary necrosis
Gross hematuria, flank pain
Causes of renal papillary necrosis
Chronic analgesic abuse, diabetes mellitus, sickle cell disease, severe acute pyelonephritis
What cancer is minimal change disease associated with?
Hodgkin lymphoma
Normal glomeruli on H&E stain, effacement of foot processes on EM, negative IF
Minimal change disease
How is minimal change disease treated?
Corticosteroids
What mediates the damage in minimal change disease
Cytokines
What is the most common cause of nephrotic syndrome in Hispanics and African Americans?
Focal segmental glomerulosclerosis
segmental sclerosis and hyalinosis on H&E, effacements of foot processes on EM, negative IF
Focal segmental glomerulosclerosis
Most common cause of nephrotic syndrome in Caucasian adults
Membranous nephropathy
Diffuse capillary and GBM thickening on H&E, granular IF due to immune complex deposition, “spike and dome” appearance on EM
Membranous nephropathy
Thick capillary membranes with “tram track appearance” on H&E, granular IF
Membranoproliferative glomerulonephritis
Type I MPGN
Associated with hepatitis B or C. Subendothelial IC deposits
Type II MPGN
Associated with C3 nephritic factor IgG antibody that stabilizes C3 convertase leading to persistent compliment activation and decreased C3 levels. Intramembranous deposits
Hematuria and RBC casts
Nephritic syndrome