RENAL DISORDERS
Renal Anatomy
Two Kidneys
10-12 cm in length
5 to 7 cm in width
2.5 cm thick
Weight of kidney: 300 grams
Location: Positioned retroperitoneally with the upper pole slightly under the 1 1 th -12th rib
Right kidney slightly lower than left d/t location of liver
Each kidney has one or more renal arteries and veins
Functions of the Kidney
• Urine production:
Urine fonned in the nephmns
• Excretion of waste products:
• Eliminates metabolic waste products (creatinine, phosphates, sulfates) 0 25-30g of urea produced and excreted daily in
urine
• Regulation of elecfrolytes: ensure the balance of sodium, chloride, potassium, calcium, hydrogen, phosphate and pH
• Blood pressure control: release renin which helps to regulate BP
• Water balance control:
• t fluid large volume diluted urine excreted o J fluid decreased volume concentrated urine excreted
• Red blood cell production: erythropoietin (EPO produced in the kidneys; lack causes anemia) stimulates the bone marrow
to make red blood cells
• Vitamin D Synthesis : calcitliol (active fonn of vitamin D which helps maintain calcium for bones and for nonnal chemical
balance in the body
• Secretion of prostaglandins: production of prostaglandin E and prostacyclin (both have vasodilatory effects and assist in
maintaining renal blood flow)
• Calcium & phosphorus balance:
• Renal clearance: ability of the kidneys to clear solutes from the plasma
Nephron
The nephron is the functional unit of the kidney
Two types of nephrons : cortical and juxtamedullmy 0 1 million nephmns per kidney o Filter waste products
o Stabilizes elecfrolytes o Maintain renal component of acid-base balance
Each nephron consists of:
Cup-like structure called the Bowman capsule o Bowman' s capsule surrounds the glomerulus o The proximal
tubule receives the ulfrafiltratethat passes thmugh the Bowman's capsule o The loop of Henle follows the
proximal tubule o The distal tubule is the final segment of the nephmn for processing urine o The collecting
tubule allows urine to be moved down to the bladder
Glomerular Filtration
• Blood flow through kidney is 1200ml/min
• Blood flow —+ afferent alteriole —+ glomerulus —+ filfration occurs
• 20% of blood passing thmugh glomerulus is filtered and produces 180L/day of filtrate
• Of the 180L/day (45 gallons); 99% reabsorbed into bloodstream with fonnation of I-2L of urine/day
, • Glomerular filtmte contains all materials present in blood except blood cells and protein which are too large to cross the
basement membrane of the glomerulus)
The Nephron: Loop of Henle
The Loop of Henle consists of 3 major segments: descending limb, thin ascending and the thick ascending limb (where the
loop diuretics will work)
15-25% of filtered sodium chloride is reabsorbed by the thic ending limb; It plays an important role in urinary
concentrating ability
Site for potent loop diuretics (Furosemide) and it contributes to reabsorption of calcium and magnesium.
Tubular secretion takes place where molecules move from the peritubular capillary' back into the tubule. Ex: hydrogen and
potassium
Secretion is the primary' process involved in removing acids, hydrogen from the body to maintain appropriate acid-base
balance
The Nephron: Distal Convoluted Tubule
• Filtrate becomes concentrated here based on the amount of ADH (anti diuretic honnone) present in blood
• ADH (AKA vasopressin is a honnone secreted by the posterior portion of the pituitmy gland in response to changes in blood
o smality
• The amount of ADH in the blood may be affected by conditions such as diabetes insipidus of the use of diuretics.
SUMMARY
• Urine fonnation is the outcome of a complex multistep process of fitration, reabsorption, secretion and excretion of water,
elecfrolytes and ,etabolic waste products
• Although urineformation is the result of this multistep process the PRIMARY function of the kidneys are to filter the blood
and maintain the body' s intemal homeostasis
Ureters
• Long narrow fibromuscular narrow tubes, 24-30 cm in length
• Located at lower portion of renal pelvis, tenninate in trigone of the bladder wall
• Left ureter shorter than right
• Most obstructions occur in these three areas:
Ureteropelvic junction
Urethral segment o
Ureterovesical junction
• Composed of circular and longitudinal muscle fibers that contract to promote a peristaltic, one-way flow of urine to the
bladder
Renal Function Tests Normal Values
,Bladder
• Reservoir for urine Specific gravity 1.010 to 1.025 300-900
• Muscular, hollow sac located behind pubic bone Urine Osmolality mosm/kg/24 H
• Contains 4 layers o Adventitia o Detrusor o
Submucosal layer of connective tissue o Inner layer 24-hour creatinine clearance - how to 125 mL/min
• Urine capacity of 400-500ml many rnL per nninute are going
through per minute
• Two inlets (ureters) and one outlet(urethra)
Serum creatinine - how well kidneys 0.6-1.2 mg/dL
Ureterovesicular Junction (UVJ) are functioning
The renal pelvis only holds small amounts of urine Urea nitrogen (BUN) to 18 mg/dL About
(3-5 ml) BUN to creatinine ratio 10:1
UVJ (where ureter and bladder meet) is dependent on
angle and muscle fibers function to prevent reflux of urine into kidneys
Urethra
• Located at the base of the bladder
• Male: it passes through the penis
• Female: opens anterior to vagina
Creatinine
• Waste product of muscle energy metabolism
• Measures the effectiveness of renal function
• Not influenced by hydration or dietary intake
• Adults: 0.6-1.2 mg/dL
• Best measure for a 24 hour urine measure
Creatinine Clearance
• Estimates the rate at which creatinine is cleared from the blood by the kidneys per 24/hours
• Detects and evaluates the progression of renal
disease
• Nonnal o Men: 95-135 ml/min o Women: 85-125 ml/min Calculated creatinine clearance:
(140-age) X weight in kg
Serum cr X 72
• 24-hour urine collection procedure: o Discard the first morning void o Save all urine for the next 24 hours,
including and ending with the first moming void on the second day o Keep the jug cooled or refrigerated
• Must also draw a blood sample
Blood Urea Nitrogen (BUN)
• Urea is the primary' end product of protein metabolism and is excreted by the kidneys
• An index or renal fimction
• Test results can be affected by protein intake, tissue breakdown, and fluid volume changes
• Adults: 7-18 mg/dL
Vocabulary
• Azotemia: increased amounts of nitrogen in the urine
• Proteinuria: increased excretion of protein in the mine (>150mg/24 h)
• Pyuria: clouded urine d/t pus fonnation in the urinary' fract (pus or WBC in urine) Dysuria: difficult and/or painfill
urination
• Oliguria: urinary output of < 400cc per day (look at how much they are allowed to drink)
, • Anuria: J of urine volume to less than 200ml per 24 hours
PYELONEPHRITIS (UPPER URINARY TRACT INFECTION)
• Bacterial infection of the upper urinaly tract, which includes the kidneys (renal pelvis, tubules and
interstitial tissue) and the ureters.
• E. coli is responsible for >80% of acute uncomplicated cases of pyelonephritis Can be acute or
chronic Caused by:
Incompetent ureterovesical valve — reflux into kidney
Cystitis
Urinaly tract obstruction
Pregnancy pressure on the bladder
Urinaly stones o
Trauma o Bladder
tumors o Sfrictures
Benign prostatic hyperplasia (BPH) pressure on the urethra
Acute Pyelonephritis
• Enlarged kidneys with interstitial infiltrations of inflammatory cells.
• Abscesses may be noted on the renal capsule and corticomedullmy junction
• Atrophy of kidney & destruction of tubules & glomemli may occur Lead to chronic renal failure
• Clinical Manifestations:
Symptoms develop rapidly over a few hours or a day and include:
Chills, fever, nausea, vomiting
Abdominal pain o
Diarrhea o
Hematuria
Flank pain, CVA tendemess
Leukocytosis o Bacteria and
WBC' s in the urine
UTI symptoms: urgency & frequency
• Pain radiates down the ureter or toward the epigastrium and maybe colicky if the infection is complicated by calculi or
sludge Diagnostics:
Urine C&S to identify causative organisms:
• Two weeks after antibiotic tx. Completed, urine is recultured, then monthly for several months.
• To locate obstructions in the urinary' tmct:
Ultrasound o
CT Scan
• To identify functional or shuctural renal abnonnalities: o IV pyelogram
• Management
High risk for bacteremia o
Antibiotics — most common is PCN
• Parenteral for 24-48 hours until patient afebrile
• Afebrile - can stmt with 0171 antibiotics (when in the hospital and takes longer to treat) Takes longer to treat than
cystitis
Hydration: Dlink at least 3 L/day of fluids; facilitates "flushing" of urinary' tract
Monitor urinary' output
Weigh daily
Pain management - analgesics and urinary' antiseptics (do not give ibuprofen because it interacts with renal fimction)
Renal Anatomy
Two Kidneys
10-12 cm in length
5 to 7 cm in width
2.5 cm thick
Weight of kidney: 300 grams
Location: Positioned retroperitoneally with the upper pole slightly under the 1 1 th -12th rib
Right kidney slightly lower than left d/t location of liver
Each kidney has one or more renal arteries and veins
Functions of the Kidney
• Urine production:
Urine fonned in the nephmns
• Excretion of waste products:
• Eliminates metabolic waste products (creatinine, phosphates, sulfates) 0 25-30g of urea produced and excreted daily in
urine
• Regulation of elecfrolytes: ensure the balance of sodium, chloride, potassium, calcium, hydrogen, phosphate and pH
• Blood pressure control: release renin which helps to regulate BP
• Water balance control:
• t fluid large volume diluted urine excreted o J fluid decreased volume concentrated urine excreted
• Red blood cell production: erythropoietin (EPO produced in the kidneys; lack causes anemia) stimulates the bone marrow
to make red blood cells
• Vitamin D Synthesis : calcitliol (active fonn of vitamin D which helps maintain calcium for bones and for nonnal chemical
balance in the body
• Secretion of prostaglandins: production of prostaglandin E and prostacyclin (both have vasodilatory effects and assist in
maintaining renal blood flow)
• Calcium & phosphorus balance:
• Renal clearance: ability of the kidneys to clear solutes from the plasma
Nephron
The nephron is the functional unit of the kidney
Two types of nephrons : cortical and juxtamedullmy 0 1 million nephmns per kidney o Filter waste products
o Stabilizes elecfrolytes o Maintain renal component of acid-base balance
Each nephron consists of:
Cup-like structure called the Bowman capsule o Bowman' s capsule surrounds the glomerulus o The proximal
tubule receives the ulfrafiltratethat passes thmugh the Bowman's capsule o The loop of Henle follows the
proximal tubule o The distal tubule is the final segment of the nephmn for processing urine o The collecting
tubule allows urine to be moved down to the bladder
Glomerular Filtration
• Blood flow through kidney is 1200ml/min
• Blood flow —+ afferent alteriole —+ glomerulus —+ filfration occurs
• 20% of blood passing thmugh glomerulus is filtered and produces 180L/day of filtrate
• Of the 180L/day (45 gallons); 99% reabsorbed into bloodstream with fonnation of I-2L of urine/day
, • Glomerular filtmte contains all materials present in blood except blood cells and protein which are too large to cross the
basement membrane of the glomerulus)
The Nephron: Loop of Henle
The Loop of Henle consists of 3 major segments: descending limb, thin ascending and the thick ascending limb (where the
loop diuretics will work)
15-25% of filtered sodium chloride is reabsorbed by the thic ending limb; It plays an important role in urinary
concentrating ability
Site for potent loop diuretics (Furosemide) and it contributes to reabsorption of calcium and magnesium.
Tubular secretion takes place where molecules move from the peritubular capillary' back into the tubule. Ex: hydrogen and
potassium
Secretion is the primary' process involved in removing acids, hydrogen from the body to maintain appropriate acid-base
balance
The Nephron: Distal Convoluted Tubule
• Filtrate becomes concentrated here based on the amount of ADH (anti diuretic honnone) present in blood
• ADH (AKA vasopressin is a honnone secreted by the posterior portion of the pituitmy gland in response to changes in blood
o smality
• The amount of ADH in the blood may be affected by conditions such as diabetes insipidus of the use of diuretics.
SUMMARY
• Urine fonnation is the outcome of a complex multistep process of fitration, reabsorption, secretion and excretion of water,
elecfrolytes and ,etabolic waste products
• Although urineformation is the result of this multistep process the PRIMARY function of the kidneys are to filter the blood
and maintain the body' s intemal homeostasis
Ureters
• Long narrow fibromuscular narrow tubes, 24-30 cm in length
• Located at lower portion of renal pelvis, tenninate in trigone of the bladder wall
• Left ureter shorter than right
• Most obstructions occur in these three areas:
Ureteropelvic junction
Urethral segment o
Ureterovesical junction
• Composed of circular and longitudinal muscle fibers that contract to promote a peristaltic, one-way flow of urine to the
bladder
Renal Function Tests Normal Values
,Bladder
• Reservoir for urine Specific gravity 1.010 to 1.025 300-900
• Muscular, hollow sac located behind pubic bone Urine Osmolality mosm/kg/24 H
• Contains 4 layers o Adventitia o Detrusor o
Submucosal layer of connective tissue o Inner layer 24-hour creatinine clearance - how to 125 mL/min
• Urine capacity of 400-500ml many rnL per nninute are going
through per minute
• Two inlets (ureters) and one outlet(urethra)
Serum creatinine - how well kidneys 0.6-1.2 mg/dL
Ureterovesicular Junction (UVJ) are functioning
The renal pelvis only holds small amounts of urine Urea nitrogen (BUN) to 18 mg/dL About
(3-5 ml) BUN to creatinine ratio 10:1
UVJ (where ureter and bladder meet) is dependent on
angle and muscle fibers function to prevent reflux of urine into kidneys
Urethra
• Located at the base of the bladder
• Male: it passes through the penis
• Female: opens anterior to vagina
Creatinine
• Waste product of muscle energy metabolism
• Measures the effectiveness of renal function
• Not influenced by hydration or dietary intake
• Adults: 0.6-1.2 mg/dL
• Best measure for a 24 hour urine measure
Creatinine Clearance
• Estimates the rate at which creatinine is cleared from the blood by the kidneys per 24/hours
• Detects and evaluates the progression of renal
disease
• Nonnal o Men: 95-135 ml/min o Women: 85-125 ml/min Calculated creatinine clearance:
(140-age) X weight in kg
Serum cr X 72
• 24-hour urine collection procedure: o Discard the first morning void o Save all urine for the next 24 hours,
including and ending with the first moming void on the second day o Keep the jug cooled or refrigerated
• Must also draw a blood sample
Blood Urea Nitrogen (BUN)
• Urea is the primary' end product of protein metabolism and is excreted by the kidneys
• An index or renal fimction
• Test results can be affected by protein intake, tissue breakdown, and fluid volume changes
• Adults: 7-18 mg/dL
Vocabulary
• Azotemia: increased amounts of nitrogen in the urine
• Proteinuria: increased excretion of protein in the mine (>150mg/24 h)
• Pyuria: clouded urine d/t pus fonnation in the urinary' fract (pus or WBC in urine) Dysuria: difficult and/or painfill
urination
• Oliguria: urinary output of < 400cc per day (look at how much they are allowed to drink)
, • Anuria: J of urine volume to less than 200ml per 24 hours
PYELONEPHRITIS (UPPER URINARY TRACT INFECTION)
• Bacterial infection of the upper urinaly tract, which includes the kidneys (renal pelvis, tubules and
interstitial tissue) and the ureters.
• E. coli is responsible for >80% of acute uncomplicated cases of pyelonephritis Can be acute or
chronic Caused by:
Incompetent ureterovesical valve — reflux into kidney
Cystitis
Urinaly tract obstruction
Pregnancy pressure on the bladder
Urinaly stones o
Trauma o Bladder
tumors o Sfrictures
Benign prostatic hyperplasia (BPH) pressure on the urethra
Acute Pyelonephritis
• Enlarged kidneys with interstitial infiltrations of inflammatory cells.
• Abscesses may be noted on the renal capsule and corticomedullmy junction
• Atrophy of kidney & destruction of tubules & glomemli may occur Lead to chronic renal failure
• Clinical Manifestations:
Symptoms develop rapidly over a few hours or a day and include:
Chills, fever, nausea, vomiting
Abdominal pain o
Diarrhea o
Hematuria
Flank pain, CVA tendemess
Leukocytosis o Bacteria and
WBC' s in the urine
UTI symptoms: urgency & frequency
• Pain radiates down the ureter or toward the epigastrium and maybe colicky if the infection is complicated by calculi or
sludge Diagnostics:
Urine C&S to identify causative organisms:
• Two weeks after antibiotic tx. Completed, urine is recultured, then monthly for several months.
• To locate obstructions in the urinary' tmct:
Ultrasound o
CT Scan
• To identify functional or shuctural renal abnonnalities: o IV pyelogram
• Management
High risk for bacteremia o
Antibiotics — most common is PCN
• Parenteral for 24-48 hours until patient afebrile
• Afebrile - can stmt with 0171 antibiotics (when in the hospital and takes longer to treat) Takes longer to treat than
cystitis
Hydration: Dlink at least 3 L/day of fluids; facilitates "flushing" of urinary' tract
Monitor urinary' output
Weigh daily
Pain management - analgesics and urinary' antiseptics (do not give ibuprofen because it interacts with renal fimction)
