Renal Disorders I Flashcards
Clinical symptoms of acute kidney injury
- oliguria
- elevated serum creatinine
Clinical signs of nephrotic syndrome
- severe proteinuria
Clinical signs of nephritic syndrome
- hematuria
Location of injury in acute kidney injury
- proximal tubule, sometimes distal tubule
Location of injury in nephrotic syndrome
- glomerular capillary filtration defect (podocyte defect)
Location of injury in nephritic syndrome
- breaks in the glomerular capillary loops
Possible diagnoses for acute kidney injury
- acute tubular necrosis
- acute interstitial nephritis
- acute pyelonephritis
Possible diagnoses for nephrotic syndrome
- membranous nephropathy
- FSGS
- minimal change disease
Possible diagnoses for nephritic syndrome
- acute nephritic syndrome: crescentic glomerulonephritis, lupus nephritis, post infectious glomerulonephritis
- isolated hematuria: IgA nephropathy, alport’s disease
Clinical indicators of renal dysfunction
- edema
- decreased renal output
- foamy urine: proteinuria
- dark or red urine: hematuria (tea colored, cola colored)
Laboratory indicators of renal dysfunction
- increased creatinine, blood urea nitrogen
- increased protein excretion (urine dipstick, urine protein/creatinine ratio, 24 hour urine protein)
- hematuria (urine dipstick, microscopic exam)
Signs of chronic kidney disease
- Glomerular sclerosis
- interstitial fibrosis
- tubular atrophy
Ways to assess renal biopsy
- light microscopy
- immunofluorescence microscopy
- electron microscopy
Patterns of immunofluorescence staining in glomerulus
- linear capillary loop pattern
- granular capillary loop pattern
- mesangial pattern
Disease associated with linear capillary loop pattern immunofluorescence stain
- Anti-GBM disease
Diseases associated with granular capillary loop pattern immunofluorescence stain
- membranous nephropathy, lupus nephritis
Diseases associated with mesangial pattern immunofluorescence stain
- IgA nephropathy, lupus nephritis
Layers of basement membrane
- lamina externa
- lamina densa
- lamina interna
Mechanisms of glomerular injury
- immune mechanisms: immune complex mediated, T-cell mediated
- non immune mechanisms: structural disorders
Disorder associated with immune complex mediated glomerular injury
- membranous glomerulopathy
Disorders associated with T-cell mediated glomerular injury
- minimal change disease
- lupus nephritis
Disorder associated with non immune glomerular injury
- alport’s syndrome
Mutation associated with alport’s syndrome
- mutation in collagen type IV gene
- leads to structural weakness in basement membrane b/c it’s composed of collagen type IV
Patient presentation and lab values seen with acute kidney injury
- decreased urinary output (oliguria), and uremia (azotemia)
- labs: increased serum creatinine, and blood urea nitrogen
Types of acute kidney injury
- pre renal
- renal
- post renal
Pre renal acute kidney injury causes
- cardiac shock, dehydration
Renal acute kidney injury
- tubulointerstitial diseases
Post renal acute kidney injury causes
- obstructive renal stone
Causes of acute kidney injury
- acute tubular necrosis
- acute interstitial nephritis
- acute pyelonephritis
Acute tubular necrosis prevelance
- MOST COMMON cause of acute kidney injury
Causes of acute tubular necrosis
- injury to tubular epithelial cells
- hypovolemia, ischemia, drug toxicity
Presentation of ATN & reversibility
- oliguria
- reversible
Key features of ATN
- tubular dilation and flattening of tubular epithelial cells
- necrotic debris in tubular lumen
Acute interstitial nephritis key featurs
- interstitial inflammation and tubulitis (lymphocytes in interstitium and in the tubule)
- EOSINOPHILS = drug induced (if eosinophils are present)
Acute pyelonephritis causes
- infections of pelvicalyceal system, and renal parenchyma
Presentation of acute pyelonephritis
- pain in cost-vertebral angle + other signs of infections
Diagnosis of acute pyelonephritis
- pus (WBC) casts
- positive urine culture
Key features of acute pyelonephritis
- similar to interstitial nephritis but inflammatory cells are NEUTROPHILS
- neutrophilic infiltrates and neutrophil casts in tubules are characteristic
Prognosis of acute pyelonephritis
- benign course if treated, symptoms disappear after treatment with antibiotics
Chronic pyelonephritis course
- may have insidious onset or a history of recurrent acute pyelonephritis
- gradual loss of renal function
- results in scarred kidney with chronic inflammation
Key features of chronic pyelonephritis
- scarred kidneys, chronic inflammation
- severe tubular atrophy, “thyroidization” of the kidney
Three clinical renal syndromes
- acute kidney injury
- nephrotic syndrome
- nephritic syndrome
