the kidney. definitions azotemia – increased bun and creatinine, usually related to decreased gfr...
Post on 29-Dec-2015
220 Views
Preview:
TRANSCRIPT
The Kidney
Definitions
Azotemia – Increased BUN and creatinine, usually related to decreased GFR
Pre-renal azotemia – hypoperfusion of the kidneys
Post-renal azotemia – obstrution to urine flow
Uremia – azotemia plus other metabolic and endocrine alterations resulting from renal damage
Definitions
Nephritic syndrome – glomerular disease, hematuria, RBC casts, mild to moderate proteinuria, hypertension, oliguria, edema
Rapidly progressive glomerulonephritis- nephritic syndrome with rapid decline (hours to days) in GFR
Nephrotic syndrome – glomerular disease, proteniuria >3.5 gm per day, hypoalbuminenia, severe edema, hyperlipidemia, lipiduria, inreased risk of infection, inreased risk of thrombosis, renal vein thrombosis
Definitions
Acute renal failure – rapid and frequently reversible onset, oliguria or anuria and recent onset of azotemia
Chronic renal failure – Prolonged symptoms and signs of uremia
Definitions
Diminished renal reserve GFR 50% of normal,
Asymptomatic
Renal insufficiency GFR 20%-50% of normal, azotemia, anemia, hypertension, decreased concentrating ability leading to polyuria and nocturia
Chronic renal failure GFR < 20% of normal, volume and solute composition cannot be regulated, edema, metabolic acidosis, hyperkalemia, overt uremia
End-stage renal disease GFR < 5% of normal, terminal stage of uremia
Chronic Renal FailureFluid and Electrolyte Dehydration
Edema
Hyperkalemia
Metabolic acidosis
Calcium, Phosphate, Bone
Hyperphosphatemia
Hypocalcemia
Secondary hyperparathyroidism
Renal osteodystrophy
Hematologic Anemia
Bleeding diasthesis
Cardiopulmonary Hypertension
CHF
Cardiomyopathy
Pulmonary edema
Uremia pericarditis
Chronic Renal Failure
Gastrointestinal Nausea and Vomiting
Bleeding
Esophagitis, gastritis, colitis
Neuromuscular Myopathy
Peripheral neuropathy
Encephalopathy
Dermatologic Sallow color
Pruritus
Dermatitis
Glomerular Diseases
Acute Proliferative Glomerulonephritis- ( poststreptococcal)
1-4 weeks after a strep infection ( pharynx or skin)Most frequently -6-10 years of ageMalaise, fever, nausea, oligouria, hematuria, RBC casts, mild proteinuria, periorbital edema, mild to moderate hypertension
Immune complex mediated diseaseEnlarged, hypercellular glomeruliGranular depositsSerum complement is decrease. ASO and other anti-strep antibodies are
increasedEM – subepithelial humpsAdults tend to present with sudden hypertension and/or edema and elevated
BUN
Glomerular Diseases
Rapidly progressive ( crescentic ) GN-Rapid and progressive loss of renal functionFormation of crescents- proliferation of parietal cells, infiltration of WBCs into the urinary space, compress the glomerular tuft, obliterate Bowman capsuleRupture of the GBM
Type I anti-GBM, e.g. Goodpasture syndromeType II Immune complex, e.g. Post-infectious GNType III pauci-immune ANCA, e.g. Wegener
granulomatosis
Causes of Nephrotic Syndrome
Primary GlomerularMembranousMinimal-changeFocal segmental glomerulosclerosisMembrano-proliferativeOther – e.g. IgA nephropathy
SystemicDMAmyloidosisSLEDrugs- NSAIDs, penicillamine, heroinInfections – malaria, syphilis, HBV, HCV,HIVMalignant diseaseMisc – e.g. hereditary nephritis
Minimal Change Disease
Most frequent cause of nephrotic syndrome in children
Visceral epithelial cells- uniform and diffuse effaement of foot processes
Immunoflorescence is negative
Membranous Nephropathy
Common cause of nephrotic in adults
Diffuse, uniform thickening of the glomerular capillary wall
Granular immunoflorescence
Subepithelial deposits
Focal Segmental Glomerulosclerosis
Most common form of nephrotic syndrome in adults
Collapsing glomerulopathy – HIV associated
Loss of foot processes
Epithelial damage
Membranoproliferative GN
Alterations in the GBMProliferation of glomerular cellsLeukocyte infiltration
Also called mesangiocapillary GN
Type I Immune complexes and activation of both classical and alternative complement pathways, subendothelial deposits
Type II dense-deposit disease activation of the alternative complement pathway
IgA Nepropathy (Berger Disease)
IgA deposits in the mesangial regions
Frequent cause of recurrent gross or microscopic hematuria
Probably the most common cause of GN worldwide
Henoch-Schonlein purpura
Secondary- liver disease and gluten enteropathy
Alport Syndrome
Hereditary nephritisHematuria with progression to chronic renal
failureNerve deafnessVarious eye disorders ( e.g. lens dislocation)Abnormalities of alpha chains in type IV
collagen
Benign Familial Hematuria
Hereditary nephritis
Asymptomatic hematuria
Diffuse thinning of the GBM
Renal function is normal
Prognosis is excellent
Lupus Nephritis
Type I – No renal involvement ( mild mesangial)
Type II – Mesangial form – granular mesangial deposits of immunoglobulin and complement
Type III – Focal-proliferative -
Type IV – Diffuse proliferative ( most severe) - crescentic
Type V – Membranous – thickening of GBM
Diabetic Glomerular Nephropathy
Widespread thickening of the GBM
Diffuse increase in mesangial matrix- expansion of the mesangium correlates with measures of deteriorating renal function
Nodular glomerulosclerosis – Kimmelsteil- Wilson disease
Tubular and Interstitial Diseases
AKI ( ATN)Acute diminution of renal failure,
and often morphologic evidence of tubular injury
Most common cause of Acute renal failure
Tubular injury and persistent and severe disturbances in blood flow
Causes – Ischemia, direct toxic injury, acute tubulointerstitial nephritis, urinary obstruction
Initiation, maintenance, recovery phases
Tubulointerstitial nephritis
Causes- infections, toxins, metabolic diseases, physical factors, neoplasms, Immunologic reactions,vascular diseases, miscellaneous
Pyelonephritis and UTI
Lower track – frequency, urgency, pyuria, dysuria, hematuria,Upper track ( pyelo) – fever leukocytosis, CVA tenderness, WBC casts
in urinepatchy interstitial suppurative inflammation, intratubular aggregates ofn neutrophils, tubular necrosis, Papillary necrosis, pyonephrosis, perinephric abscess, pyelonephritic scar-inflammation, fibrosis, deformation of underlying calyx and pelvis
E. Coli most commonAscending infection VUR, obstruction, instrumentation, pregnancy, preexisting renal
lesions, DM, immunosuppression
Vascular Diseases
Benign nephrosclerosis- hyaline arteriosclerosis
Malignant nephrosclerosis – fibrinoid necrosis and onion-skinning
Renal artery stenosis – most common cause is atherosclerosis, fibromuscular dysplasia
Renal infarction – white – end-organ
Thrombotic Microangiopathies
Microangiopathic hemolytic anemiaThrombocytopeniaRenal failure ( in many cases)Thrombotic lesions in capillaries and arteriolesEndothelial injuryPlatelet aggregationTypical ( epidemic, classic, diarrhea-positive) HUS- Shiga-like toxins,
E. coli 0157:H7Atypical ( non-epidemic, diarrhea-negative) HUS- genetic mutations in
complement-regulatory factors, antiphospholipid syndrome, postpartum, vascular diseases, drugs, irradiation
Thrombotic Thrombocytopenia Purpura – ADAMTS13, CNS involvement dominant
Cystic Diseases
Adult polycystic kidney disease – AD, CRF later in life, berry aneurysms, hepatic cysts,MVP and other valvular lesions
Childhood polycytic kidney disease- AR, Death in infancy or childhood, hepatic fibrosis
Urinary Tract Obstruction
Common causes: Congenital anomaliesUrinary calculiBPHTumorsInflammationSloughed papillae or blood clotsPregnancyUterine prolapse and cystoceleFunctional disorders – neurogenic bladderHydronephrosis – Dilation of the renal pelvis and calyces associated with
progressive atrophy of the kidney due to obstruction to the outflow of urineObstruction also triggers an interstitial inflammatory reaction, leading eventually
to interstitial fibrosis
Urolithiasis
Calcium stones- oxalate and/or phosphate
Triple stones – magnesium ammonium phosphate, infections, staghorn calculi
Uric acid stones
Cystine
Tumors
Renal cell carcinoma – adenocarcinoma. Smoking, obesity, unopposed estrogen,Asbestos, petroleum products, heavy metalsCRF, acquired cystic disease, tuberous sclerosisvon Hippel-LindauClear cell- 70-80%CVA pain, palpable mass, hematuriaParaneoplastic syndromes, widespread metastases before local signs and symptoms
top related