RENAL LECTURE NOTES Flashcards
Blood Vessels
l ___________ – most richly vascularized part;
receives 90% of total renal blood supply
l Renal artery–> interlobar arteries –>arcuate arteries –>interlobular arteries–> l Afferent arterioles enter glomerular tuft; subdivide into 20 to 40 capillary loops
l Capillary loops merge to exit as efferent arterioles
Cortex
What is the blood flow of the kidney?
l Renal artery–> interlobar arteries –>arcuate arteries –>interlobular arteries–> l Afferent arterioles enter glomerular tuft; subdivide into 20 to 40 capillary loops
Note: l Capillary loops merge to exit as efferent arterioles
Blood Vessels
l Efferent arterioles from superficial nephrons form _____________
peritubular vascular network
l Deeper juxtamedullary glomeruli give rise to ____________
vasa recta
l Vasa recta descend as straight vessels to supply _____________
outer and inner medulla
l Anastomosing network of capillaries lined by fenestrated endothelium invested by two layers of epithelium
l Visceral epithelium – part of the capillary wall; separated from endothelial cells by a basement membrane
l Parietal epithelium – lines the urinary space (cavity in which plasma filtrate first collects)
Glomeruli
____________– part of the capillary wall; separated from endothelial cells by a basement membrane
)
l Visceral epithelium
____________ – lines the urinary space (cavity in which plasma filtrate first collects
l Parietal epithelium
Glomerular capillary wall – filtering membrane and consists of:
- Endothelial cells
- Glomerular basement membrane (GBM)
– lamina densa,
lamina rara interna
and externa
- Visceral epithelial cells (podocytes)
– foot processes and filtration slits
- Mesangial cells – lie between capillaries; basement membrane-like mesangial matrix
§ Contractile, phagocytic, capable of proliferation, lay down both matrix and collagen, secrete biologically active mediators
§ Important players in many forms of glomerulonephritis
Mesangial cells:
Glomeruli Major characteristics of normal glomerular filtration:
§ High permeability to water and small solutes
§ Impermeability to proteins (albumin)
– glomerular barrier function (size- and chargedependent)
________________- is important for the maintenance of glomerular barrier function
l Proteins located in slit diaphragm control glomerular permeability
l Mutations in genes encoding proteins give rise to nephrotic syndrome
l Visceral epithelial cell (slit diaphragm)
_______________
: l Reabsorption of 2/3 of filtered Na, H2O, glucose, K, phosphate, amino acids and proteins
l Vulnerable to ischemic damage
l Toxins are frequently reabsorbed rendering it susceptible to chemical injury
Tubules Proximal tubules
Tubules Juxtaglomerular apparatus:
l JG cells – modified smooth muscle cells in the media of afferent arteriole; produce renin
l Macula densa
l Lacis cells or nongranular cells – resemble mesangial cells
________- – modified smooth muscle cells in the media of afferent arteriole; produce renin
JG cells
_________________– resemble mesangial cells
Lacis cells or nongranular cells
l Normal cortex: compact interstitial space occupied by peritubular capillaries and fibroblast-like cells
l Expansion of the cortical interstitium is abnormal (edema or inflammatory cells)
Interstitium
___________– elevation of BUN and creatinine levels;
related to decreased GFR
Azotemia
_________– hypoperfusion of the kidneys (hemorrhage, shock, volume depletion, CHF) that impairs renal function in the absence of parenchymal damage
l Prerenal
____________– urine flow obstruction below the level of kidney
l Postrenal
___________
l Azotemia with S/Sx
l Characterized by failure of renal excretory function and metabolic and endocrine alterations
Uremia
Principal Systemic Manifestations
of CRF and Uremia
Fluid and Electrolytes:
l Dehydration
l Edema
l Hyperkalemia
l Metabolic acidosis
Calcium Phosphate and Bone:
l Hyperphosphatemia
l Hypocalcemia
l Secondary hyperparathyroidism
l Renal osteodystrophy
Hematologic:______________
l Anemia l Bleeding diathesis
Cardiopulmonary:
l HPN
l CHF
l Cardiomyopathy
l Pulmonary edema
l Uremic pericarditis
Gastrointestinal:
l Nausea and vomiting l Bleeding l Esophagitis, gastritis, colitis
Neuromuscular: l
Myopathy l Peripheral neuropathy l Encephalopathy
Dermatologic:
l Sallow color
l Pruritus
l Dermatitis
CLINICAL MANIFESTATIONS OF RENAL DISEASES l Acute nephritic syndrome
l Nephrotic syndrome
l Rapidly progressive glomerulonephritis –
l Acute renal failure –
l Chronic renal failure
_____________________ – nephritic syndrome with rapid decline (hours to days) in GFR
Rapidly progressive glomerulonephritis
______________ – oliguria or anuria with recent onset azotemia; can result from glomerular, interstitial, vascular or acute tubular injury
Acute renal failure
___________ – prolonged S/Sx of uremia; end result of all chronic renal parenchymal diseases
Chronic renal failure
Polyuria, nocturia, electrolyte disorders – ______________
renal tubular defects
l Bacteriuria and pyuria – _______________
UTI
l Renal colic, hematuria – ___________________
nephrolithiasis
l Asymptomatic hematuria or proteinuria ________________
– subtle glomerular abnormalities
GLOMERULAR DISEASES Primary Glomerulopathies:
l Acute proliferative glomerulonephritis – postinfectious, other
l Rapidly progressive (crescentic) glomerulonephritis
l Membranous glomerulopathy
l Minimal change disease
l Focal segmental glomerulosclerosis
l Membranoproliferative glomerulonephritis
l IgA nephropathy
l Chronic glomerulonephritis
GLOMERULAR DISEASES
Systemic Diseases with Glomerular Involvement:
l SLE
l DM l
Amyloidosis
l Goodpasture syndrome
l Microscopic polyarteritis/polyangiitis
l Wegener granulomatosis
l Henoch-Schönlein purpura
l Bacterial endocarditis
GLOMERULAR DISEASES
Hereditary Disorders:
l Alport syndrome
l Thin basement membrane disease
l Fabry disease
