Nephrology

By C.Settley
Compiled by C.Settley 2018

• Apply knowledge regarding:
– patho-physiology
– disease process
– clinical manifestations
– specific diagnostic and therapeutic interventions (diagnostic tests and examinations)
• Distinguish between the different health problems: medical and surgical conditions of
various body systems
– Glomerulo –nephritis
– Nephrotic syndrome
– Renal failure
– Wilms tumor
• Assess, relate and apply the scientific process of nursing
• Provision and facilitation of nursing care
• Evaluate, analyse and solve problems in familiar and unfamiliar context in the
Comprehensive Health Care system
• Understand the relationship between social, cultural and economic factors that may impact
significantly on the health status of clients / patients and groups. (Health education)
• Ability to apply knowledge of emergency and trauma management principles

• The kidneys are two bean-shaped organs, each about the size
of a fist.
• They are located just below the rib cage, one on each side of
the spine.
• The urine flows from the kidneys to the bladder through two
thin tubes of muscle called ureters, one on each side of the
bladder.
• The bladder stores urine. The muscles of the bladder wall
remain relaxed while the bladder fills with urine. As the
bladder fills to capacity, signals sent to the brain tell a person
to find a toilet soon. When the bladder empties, urine flows
out of the body through a tube called the urethra, located at
the bottom of the bladder.
• In men the urethra is long, while in women it is short.

• Prevent the build-up of wastes and extra
fluid in the body
• Keep levels of electrolytes stable, such as
sodium, potassium, and phosphate
• Make hormones that help:
– Regulate blood pressure
– Make red blood cells
– Bones stay strong

• The kidney is not one large filter.
• Each kidney is made up of about a million filtering units called
nephrons.
• Each nephron filters a small amount of blood.
• The nephron includes a filter, called the glomerulus, and a
tubule.
• The nephrons work through a two-step process.
• The glomerulus lets fluid and waste products pass through it;
however, it prevents blood cells and large molecules, mostly
proteins, from passing.
• The filtered fluid then passes through the tubule, which sends
needed minerals back to the bloodstream and removes
wastes.
• The final product becomes urine.

• The kidney is the main excretory organ to
eliminate metabolic waste products,
including metabolites.
• About 25-30g of urea, the main waste
product of protein must be excreted daily.
• Other metabolic waste products include
creatinine, phosphates, sulphates and uric
acid.

• The kidneys are responsible for keeping the
homeostatically constant, which is achieved
by regulating the volume and concentration
of body fluids by selectively filtering and
reabsorbing materials from the blood.
• To achieve this, the kidneys are controlled by
various factors and the neural and endocrine
systems act from outside the excretory
system to help achieve this balance. Apart
from that the kidneys also have their own
auto-regulation mechanism.

• The volume of fluid in various fluid compartments in the body depends on the balance of
fluid intake and fluid output. Fluid intake in response to thirst is a source of fluid, and
receptor cells found in the hypothalamus activate thirst when exposed to hypertonic
conditions - such as when water loss has been excessive or salt intake high.
• These receptor cells will only cease to give a thirst message when the hypertonic status has
been corrected.
• A large intake of fluid will also be corrected by the specialized receptors in the nervous
system, since they monitor the changes in blood volume. Should you for instance take in a
liter of fluid, the kidneys will excrete the excess, simply by increasing its urine production
eight fold within thirty minutes.
• When blood volume increases the pressure is increased within the atria of the heart which
then activates stretch receptors, which in turn send a signal for reduction of ADH release in
the posterior pituitary, leading to less fluid to be reabsorbed by the kidneys. It secondly
reduces the vasomotor tone of the blood vessels, which leads to dilation of the blood
vessels, causing an increase of the glomerular blood pressure and increased filtration is
achieved, with less water being reabsorbed by osmosis.
• The reserve happens when blood volume decreases and less urine is formed with more
fluid being retained and so correcting blood volume.

• Anti-diuretic hormone (ADH) and kidney function
kidney functioning
• The primary effect of ADH is to limit the amount of
water being lost in urine, by increasing the amount of
water being reabsorbed into the blood. The ADH
targets the cells of the tubules and collecting ducts,
which causes an increase of permeability of the cell
surfaces, where the water then leaves the renal tubules
by means of osmosis.
• With more fluid being reabsorbed, the blood volume
increases while the solutes concentration becomes
more diluted.

• Feedback control of ADH release and
kidney function kidney functioning
• As soon as the osmolarity of the blood and
body fluids is reduced, with more fluid being
reabsorbed by the tubules in the kidneys, the
receptors in the hypothalamus are no longer
stimulated and the level of ADH stimulation is
reduced, which then in turn signals to the
kidneys to start excreting more water in the
urine production until the blood osmolarity
increases enough for the cycle to be started
again.

• Aldosterone hormone - regulation of sodium and potassium
and kidney function kidney functioning
• ADH is not the only hormone that helps with the regulation of
kidney function - aldosterone (from the adrenal cortex) as well as
parathyroid hormone (from the parathyroid glands) affects the
balance and regulation of electrolyte content of the blood and body
fluids.
• When aldosterone is present in the blood, the distal renal tubules
increase their re-absorption of sodium and the secretion of
potassium. With this action, more water is retained in the body and
a person with high aldosterone content can have “puffy” features
from the increased water volume.
• Aldosterone is secreted by the adrenal glands when the level of the
potassium in the blood is increased, as well as the self-regulatory
action of the kidneys by means of the renin-angiotensin system.

• Renin-angiotensin system of kidney function
kidney functioning
• When blood pressure increases so does the
glomerular filtration increase, but when blood pressure
falls, the filtration level drops and the glomerular
filtration rate then needs another system to increase
the filtration rate.
• This is made possible with tubuloglomerular feedback
where a specialized region of the nephron - the
juxtaglomerular complex - will detect the decreased
fluid flow within the nephron tubules and will increase
the glomerular filtration.

• Aldosterone and Renin-Angiotensin system of kidney function kidney
functioning
• The renin-angiotensin system will not only assist to increase filtration of the
glomerular, but can also affect the adrenal secretion of aldosterone, which
will help to bring the low systemic blood pressure up to normal.
• Parathyroid hormone and calcium and phosphate regulation kidney
functioning
• Parathyroid hormone (PTH) is responsible for the endocrine regulation of
calcium and phosphate. When blood levels of calcium decrease it stimulates
the production of PTH, which has three physiological effects, one having a
direct bearing on the kidneys.
• In the kidneys the parathyroid hormone increases calcium re-absorption in
the renal tubules, while phosphates are not really affected.

• Metabolic wastes kidney functioning
• The kidneys are primarily involved in removing
nitrogen-containing wastes to prevent toxic build-up.
• The metabolic wastes occur during breakdown of
nitrogen-containing proteins and purine nitrogenous
bases. This metabolism also involves the removal of
nitrogen from amino acids and amino nitrogen is often
removed as ammonia, which is extremely toxic to cells
and needs to be removed from the blood and body
fluids. The liver cells can also combine amino nitrogen
with carbon dioxide, which then produces urea.

• Urea waste kidney functioning
• Urea is excreted by the kidneys, and is less
toxic than ammonia and can be transported
in the blood from the liver where it is formed
from ammonia. This molecule is very small,
diffuses easily across cell membranes and
requires no specialized transport system.
• It is osmotically active and can function in
regulating osmotic pressure of blood and
other body fluids.

• Uric acid waste kidney functioning
• Uric acid is less toxic than urea and is also excreted by
the kidneys, and while it is a bigger molecule than urea
and less soluble, the uric acid that appears in urine is
mostly secreted by the tubule cells in the kidneys.
• Uric acid is formed from the metabolism of nucleic
acids. Nucleotides adenosine and guanosine are
purine nucleotides as they contain purine nitrogenous
bases, which are double-ring organic compounds,
which also contain nitrogen in their ring structure.
Nucleotide metabolism metabolizes purine
nitrogenous bases to uric acid by the liver cells.

• The renin-angiotensin system or RAS
regulates blood pressure and fluid balance in
the body. When blood volume or sodium
levels in the body are low, or blood
potassium is high, cells in the kidney release
the enzyme, renin. Renin converts
angiotensinogen, which is produced in the
liver, to the hormone angiotensin I. An
enzyme known as ACE or angiotensin-
converting enzyme found in the lungs
metabolizes angiotensin I into angiotensin II.

• Angiotensin II causes blood vessels to constrict
and blood pressure to increase. Angiotensin II
stimulates the release of the hormone aldosterone
in the adrenal glands, which causes the renal
tubules to retain sodium and water and excrete
potassium. Together, angiotensin II and
aldosterone work to raise blood volume, blood
pressure and sodium levels in the blood to restore
the balance of sodium, potassium, and fluids. If the
renin-angiotensin system becomes overactive,
consistently high blood pressure results.

• When the kidneys detect a decrease in the
concentration of oxygen in the circulating
renal blood, they release erythropoietin.
• This is a hormone that is sensitive to a
decrease in the circulating blood oxygen.
• It stimulates the bone marrow to generate
red blood cells, thereby increasing the
amount of haemoglobin to increase
oxygen uptake.

• The kidneys are responsible for the
conversion of the inactive vitamin D to the
active 1,25-dihydroxycholecalciferol to
maintain calcium balance in the body.
• This is important in bone formation as well
as muscle contraction.

• Infections/inflammatory
– Urethritis
– Cystitis
– Urethritis
– Pyelonephritis
– Glomerulonephritis

• Obstructive
– Benign and malignant tumours in the renal
system
– Renal calculi

• Acquired structural defects
– Renal failure
• Congenital defects
– Solitary kidney
– Ectopic/ duplicate kidney

• Trauma to the kidney, bladder ureters,
urethra
– Rupture
– Damage

• Upper urinary tract
– Kidney
• Nephritis
• Glomerulonephritis
• Pyelonephritis
• Nephrotic syndrome
• Renal failure
• Kidney stones
• Renal trauma
• Cancer of the kidney

• Upper urinary tract
– Ureters
• ureteritis

• Lower urinary tract
– Bladder
• Cystitis
• Neurogenic bladder
• Bladder stones
• Dysfunctional bladder
– Urethra
• Urethritis

• Dehydration
• Hypertension
• Nephrotoxic medications
• Diseases
• Hyperparathyroidism
• Advanced age
• Immobility
• Exposure to environmental chemicals
• Instrumentation
• Pelvic surgery
• Spinal cord injury
• Childbirth
• Prostatic hypertrophy
• Diet high in calcium
• lifestyle

• Personal history
– Age, gender, marital status, occupation,
hobbies, religious beliefs & economic status
– May be related to complaints

• Health history
– Present and past
– Urinary tract infections
– Medication usage
– Patterns of micturition
– Risk factors
• Female
• Births
• Neurologic diseases
• Older men
• History of scabies
• Explore other signs and symptoms
• Anxiety levels

• Physical examination
– Head to toe
– Palpation, auscultation and percussion
– Skin
– Pallor, cyanosis
– Bruising
– Scars
– Fingernails
– Dehydration
– Oedema
– Fatigue
– Weight gain
– Abdominal pain

• Measurement of weight
• Urine studies
– Daily
– Culture
– 24 hour urine specimen
– Concentration
– (see chapter 7 for complete urine studies)

• :: Glucose
• :: Ketones
• :: Blood / Hemoglobin
• :: Protein
• :: Nitrite
• :: pH
• :: Urobilinogen
• :: Bilirubin
• :: Leucocytes
• :: Specific gravity

• Blood studies
– FBC
– Urea
– Electrolytes
– Arterial blood gases
– Blood urea nitrogen

• Intravenous pyelography
– Intravenous pyelography refers to a series of X-rays taken of the
kidneys, their collecting or drainage system (the ureters), and the
bladder. The ureters are the small tube-like structures that
connect the kidneys to the bladder.
– An intravenous pyelogram (IVP) may be performed to detect a
problem of the kidneys, ureters, and bladder. Most often, the IVP
is done to locate a suspected obstruction to the flow of urine
through the collecting system. The most common cause of
blockage is a kidney stone. The IVP test also gives information
about the functioning of the kidneys.
– In an IVP test, dye is injected via a catheter inserted in a person's
vein, usually on the hand or the forearm. X-rays are then taken
to follow the track of the dye through the system.

• CT
– Computed tomography (CT scan or CAT scan)
is a non-invasive diagnostic imaging
procedure that uses a combination of X-rays
and computer technology to produce
horizontal, or axial, images (often called slices)
of the body.
– A CT scan shows detailed images of any part
of the body, including the bones, muscles, fat,
and organs. CT scans are more detailed than
standard X-rays.

• MRI
– Produces a three dimensional image of the
renal tissues by using magnetic energy.
– Prepare the patient: explanation of procedure
& metallic objects should be removed.

• Ultrasound
– Non invasive x-ray
– Sound waves passed into the body via a
transducer.
– Meant to detect abnormalities such as fluid
accumulation, masses, changes in organ size
and obstruction.

• Renal biopsy
– Renal biopsy is a medical procedure in which a
small piece of kidney is removed from the
body for examination, usually under a
microscope.

• Endoscopy
– The procedure is carried out by a urologist
(doctor specialising in the urinary system) and
a radiologist (doctor specialising in imaging
techniques).

• Acute inflammation of the kidney, typically
caused by an immune response.
• PRIMARY: disease starts in the
glomerulus
• SECONDARY: the disease results from
systemic diseases
• Both primary and secondary can be acute
or chronic

• Acute Glomerulonephritis
– In children, a common cause of
glomerulonephritis is from a streptococcal
infection, such as strep throat or upper
respiratory infection.
– Glomerulonephritis usually occurs more than
one week after an infection. This is often
referred to as acute post streptococcal
glomerulonephritis or APSGN.

• Acute Glomerulonephritis: Pathophysiology
– Occurs as a result of antigen-antibody reaction
– The antigen antibody complexes in the circulation
stimulate inflammation, which results in damage
to the kidneys
– When the glomerulus is injured, its membrane’s
porosity is increased, thus allowing proteins and
red blood cells to filter through the glomerular
filtrate into the renal tubules, resulting in
proteinuria and haematuria

• Acute Glomerulonephritis: clinical
manifestations
– Proteinuria with or without haematuria
– Orbital oedema
– Weight gain
– Hypertension
– History of recent upper respiratory tract
infection
– Flank pain, headache, fever

• Acute Glomerulonephritis: diagnostic
studies
– Routine and lab urine tests
– Blood tests
– Throat swabs

• Bed rest
• Weighed daily
• Intake and output measured
• Daliy urine tests
• Infection preventative measures
• Diuretics
• Antihypertensive meds
• Corticosteroids diet
• See table 24,1, page 453

• Educate
• Process of disease
• Medication
• Diet
• Follow up

• A kidney disorder that causes the body to excrete
too much protein (proteinuria) in the urine.
• Nephrotic syndrome is often caused by damage to
small blood vessels in the kidneys that filter waste
and excess water from the blood. An underlying
health condition usually plays a role.
• Symptoms include swelling around the eyes and in
the feet and ankles, foamy urine and weight gain
due to excess fluid retention.
• Treatment addresses underlying conditions and
might include blood pressure medication and
water pills.

• Aetiology
– Often seen in children under the age of 16
– Peak incidence between the ages of 5-8
– Conditions that produce this syndrome
include acute and chronic glomerulonephritis,
infections, chronic diseases, congestive cardiac
failure and renal transplant

• Pathophysiology
– When the glomerular basement membrane is
damaged, there is an increase in permeability
that allows protein molecules to leak out
through the bowman’s capsule and proximal
tubule

• Pathophysiology

• Pathophysiology
– As the condition worsens, larger proteins also
leak out and are excreted in urine
– As the body continues to lose proteins, serum
albumin is decreased resulting in a decrease in
osmotic pressure.
– Generalised oedema occurs due to low
osmotic pressure

• Pathophysiology
– Circulating volume decreased as a result of
loss of fluid to the interstitial spaces, resulting
in the stimulation of aldosterone and the
action of angiotensin II to bring about
vasoconstriction and elevated blood pressure
– In cases where BP is not triggered, it may
actually drop due to the reduction of the
circulating volume

• Pathophysiology
– Sodium and water retention occurs, causing
more oedema
– The disease progress to renal failure due to
persistent hypovolaemia and accelerated
atherosclerosis as a result of hyperlipidaemia.

• Assessment and common findings
– There may be a history of glomerular disease
– Anasarca
– Proteinuria
– Hyper proteinuria (exceeding protein of 3grams per day)
– Hyperlipidaemia
– Hypertension
– Fatigue
– Anorexia
– Malaise
– Irritability
– Headache
– Blood tests to be done for protein and lipid analysis
– Will result in findings of high cholesterol and triglycerides
– Renal biopsy can be done to detect the extent of renal damage

• Nursing management
– Diuretics
– Strict intake and output
– Corticosteroids
– Daily urine test
– High protein diet
– Restricted ssoduim diet
– Increase calories
– Bed rest
– Infection prevention
– Daily weight

• How does the kidneys maintain
homeostasis?
• Regulate water, electrolytes, eliminate
waste products, except carbon dioxide.
• Regulate Ph
• When excretion is impaired, this will result
in disturbances in above mentioned
• Acute or chronic

• Acute renal failure
• Rapid decline/loss of kidney function due
to sudden decrease in glomerular filtration
rate.
• Results in acute tubular necrosis.
• Oliguria (less than 400 ml/day of urine) is a
common manifestation. Though it is not
always present.
• Rise in serum creatinine and BUN levels

• Acute renal failure: Causes
• Prerenal
– Causes a drop in blood supply to the kidneys
– Resulting in hypo perfusion of the kidneys and
thus a drop in glomerular filtration rate
– Fluid volume depletion
– Vasodilatation & impaired cardiac function are
major prerenal causes of ARF.

• Intrarenal
– Conditions that cause structural damage to
the parenchyma or tubules of the kidneys.
– Conditions such as infections, injuries and
nephrotoxic agents incl NSAID’s.

• Postrenal
– Is caused by obstruction in the collecting system
above the urinary bladder or anywhere below the
bladder.
– The obstruction causes reflux of urine and an
increase in the pressure inside the kidneys.
– This may result in permanent loss of function if
the obstruction is long standing.
– SEE TABLE 24.2, Page 457 for summary

• Acute renal failure: Pathophysiology
– Occurs as result of direct decrease in renal blood
supply, causing damage to the kidneys
– The tubular damage includes sequestration of the
glomerular filtrate in the tubules, whereby the
lumen will be blocked by sloughed necrotic
tubular cells
– The filtrate then leaks back into the interstitium
through damaged tubular cells and stimulates the
renin-angiotensin mechanism resulting in a raised
BP.

• Common assessment findings
• Prevention
• Management
– Pages 458-459

• Chronic renal failure
– Irreversible loss of function of nephrons that
results in the retention of metabolic waste
products in the body as well as electrolyte
imbalances
– End stage renal disease is used to describe
chronic renal failure because chronic renal failure
is fatal unless alternative means are used to
excrete waste products, excessive fluid and
correct the imbalances
– Related to an underlying cause and the patient’s
level of renal function and the presence of
hypertension at the time of the diagnosis

• Chronic renal failure: causes
– The same as for ARF

• Chronic renal failure: Pathophysiology
– Waste products eventually accumulate in the
body as renal function declines
– Stage 1: reduced renal reserve
– Stage 2: renal insufficiency
– Stage 3: end stage renal disease

• Chronic renal failure: assessment and
common findings
– Affects all body systems
– Gastrointestinal system: metallic taste in the
mouth. Gingivitis, ulcers and bleeding in the
mouth. Loss of appetite, nausea and vomiting,
constipation or diarrhoea

common findings
– Respiratory system: change in breathing
patterns. Kussmaul’s breathing. Depressed
cough reflex. Thick secretions and crackles can
be detected on auscultation. Pleuritis and
pulmonary oedema

common findings
– Cardiovascular system: symptoms related to
fluid accumulation such as oedema of the
hands and feet, periorbital oedema and
distended neck veins. Electrolyte imbalances,
especially potassium. Hypertension and
pericarditis.

common findings
– Musculo skeletal system: uraemic frost is the
whitish flakes that appear on the skin as result
of the excretion of uric acid through the skin.
The skin will also be pale and dry. Calcuim and
phosphorus imbalances cause bone pain, loss
of muscle growth, easy fractures and retarded
growth. Hair becomes dry and brittle.

common findings
– Central nervous system: changes are related
to the level of consciousness, orientation and
confusion. Changes in behaviour and seizures
are also normal.

common findings
– Reproductive manifestations: amenorrhoea,
infertility, decreased libido and testicular
atrophy. Hypothyroidism and
hyperpapathyroidism are the systemic effects
of uraemia.
– Metabolic effects are hyperglycaemis,
hypertriglycerideamia, hyperuricaemia and
metabolic acidosis.

common findings
– Aneamia and thrombocytopaenia: these
symptoms are present as a result of impaired
erythroprotein production and platelet
function.
– There is increased susceptibility to infection
and bleeding tendencies.

• Diagnostic studies
• Management of CRF
• Drug therapy
• Nursing management
• General nursing care plan
• Essential health information
– Pages 420-462,

• The process of removing excess water,
solutes and toxins from the blood in those
whose native kidneys have lost the ability
to perform these functions in a natural
way. This is referred to as renal
replacement therapy.

• One needle will slowly
remove blood and
transfer it to a machine
called a dialyser or
dialysis machine. The
dialysis machine is made
up of a series of
membranes that act as
filters and a special liquid
called dialysate. The
membranes filter waste
products from the blood,
which are passed into the
dialysate fluid.

• Home dialysis (CAPD ‐ continuous
ambulatory peritoneal dialysis) is a 'do it
yourself' option that does not require a
machine. It involves a tube permanently
inserted through the abdomen to allow a
fluid called dialysate to be emptied and
replaced every day

• One type of renal replacement therapy —
meaning a treatment that replaces kidney
function — is hemodialysis. Hemodialysis
is a therapy that filters waste, removes
extra fluid and balances electrolytes
(sodium, potassium, bicarbonate, chloride,
calcium, magnesium and phosphate).

• Mogotlane, S. Chauke, M. Matlakala, M, Mokoena , J. &
Young, A. (eds). 2013. Juta’s complete Textbook of Medical
Surgical Nursing. Cape Town: Juta.
• https://www.niddk.nih.gov/health-information/kidney-
disease/kidneys-how-they-work
• http://teachmeanatomy.info/abdomen/viscera/kidney/
• https://www.urologyhealth.org/urologic-conditions/kidney-
cancer
• http://slideplayer.com/slide/8527886/
• http://www.edren.org/pages/edreninfo/glomerular-basement-
membrane-disorders.php
• http://www.bbc.co.uk/schools/gcsebitesize/science/triple_aqa/
homeostasis/removal_waste_water_control/revision/4/

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