4 - Urinary Elimination: Acute Kidney Injury + Urinary Tract Disorders Flashcards
What is the main cause of glomerulonephritis?
Glomerulonephritis is mainly caused by immune-mediated factors such as:
- post-infectious disease (streptococci, pneumococci, hep B, mononucleosis, measles, mumps, malaria)
- sepsis
- endocarditis
- lupus
- rheumatic disease
- idiopathic
Describe the common clinical presentation of nephritic syndrome.
The common clinical presentation of nephritis syndrome involves:
- hematuria
- proteinuria
- reduced GFR
- hypertension
What are the 3 common paths that nephritic syndrome follows?
- acute glomerulonephritis
- rapidly progressive glomerulonephritis
- chronic glomerulonephritis
Describe acute glomerulonephritis
Abrupt onset of symptoms often result in acute renal failure, followed by a full recovery of renal function
Describe rapidly progressive glomerulonephritis
Abrupt onset of symptoms in which recovery from acute renal failure does not occur
Over weeks to months - this disorder progresses to chronic renal failure
Describe chronic glomerulonephritis
Acute glomerulonephritis which progresses slowly over a period of years (ex. 5-20) to chronic renal failure
What does APSGN stand for?
Acute Post-Streptococcal GlomeruloNephtritis
What causes apsgn?
APSGN occurs b/c of an immune attack on a streptococcal antigen - results in immune complex + complement deposits in the glomerular capillaries
When do nephritic manifestations occur in APSGN? When do they usualy resolve?
Nephritic manifestations usually occur 7-10 days after the onset of a pharyngeal or cutaneous infection w group A streptococcus (ex - streptococcus pyogenes) and resolve over a period of weeks.
Which population does APSGN usually effect? Is it more common in girls or boys?
APSGN usually effects children between ages 3-7 and is more common in boys
Describe the manifestations of APSGN and why they occur
- hematuria + proteinuria occur due to damage to the glomerular capillaries
- decreased GFR, oliguria and azotemia occur due to the infiltration of inflammatory cells into the glomerulus
- pain in the flank or lower back due to distension of the renal capsule
- hypertension + edema (facial + preorbital) as a consequence of fluid and salt overload due to a reduced GFR
- metabolic acidosis
- elevation of antibodies to streprococcal antigens
How do we typically treat nephritic syndrome?
- most cases resolve w a diuretic phase after treatment for the infection
- may not be as easily resolved in adults and some cases ultimately progress to renal failure
What does nephrotic syndrome result from?
What does it occur secondary to?
nephrotic syndrome results from inflammation of the glomerulus w/o the presence of cellular immune cells
nephrotic syndrome occurs secondary to a number of disorders including infection, lupus, exposure to nephrotoxins, neoplasia, diabetic nephropathy and immune-mediated
Identify the side effects of nephrotic syndrome + why they occur.
- commonly presents as: proteinuria, hypoalbuminemia, generalized edema (due to reduced colloid osmotic pressure), hyperlipidemia, and lipid in the urine (milky appearance)
- third spacing: dependent edema, ascites, effusions + weight gain, due to reduced colloid osmotic pressure
- hyperlipidemia r/t decreased colloid osmotic pressure (liver increases procution of lipoproteins resulting in elevated LDL + VLDL)
- hypovolemia which manifests as syncope, circulatory shock, and acute azotemia
Why are some cases of nephrotic syndrome are considered to be minimal change diseases?
Called minimal change diseases when all manifestations occur as a result of proteinuria and progression to uremia does NOT occur
Describe how we typically treat nephrotic syndrome.
- usually treated w/ glucocorticoids to reduce glomerular inflammation
- Lasix + spironolactone (for fluid + electrolyte control)
What are the second most common infections seen by HCPs?
urinary tract infections
T or F: most UTIs are descending infections and arise from microbes entering the urethra
false - ascending infections.
What is the major host defense against ascending infection? What is a major contributing factor of UTIs?
- Major host defense is the flushing effect of urine flow
- Therefore stasis of urine is a major contributing factor
Which type of bacteria is the most common cause of UTIs? What is the second most?
Opportunistic E. coli infections is the most common cause of UTIs
Second most common is fecal proteus bacteria
Why are females and older males more susceptible to UTIs?
Women: anatomical vulnerability (short, wide urethra, close proximity to anus)
Older men: enlarged prostate - retantion of urine (stasis) + frequent UTIs
Why are diabetics at a higher risk of UTIs?
Diabetics are at a high risk of developing UTIs due to glucosuria - as it provides an additional energy source for some bacterial strains
Identify the risk factors that predispose pts to UTIs
- women
- older males
- incomplete bladder emptying
- obstruction of urine flow
- incontinence
- pregnancy
- scar tissue
- congenital defects of the ureter
- impaired blood supply to bladder
- catheterization
- sexual intercourse
What is cystitis?
Inflammation of the bladder
What are the 4 clinical manifestations of cystitis?
- PAIN (abdominal + during micturition [peeing])
- frequency + urgency due to reduced bladder capacity r/t swelling + inflammation
- systemic signs of infection (fever, malaise, nausea, leukocytosis)
- cloudy urine w unusual odour due to bacteriuria, pyuria, microscopic hematuria
How do we typically treat cystitis?
- antibiotic therapy w/ increased fluid intake to help eliminate evading organisms
- cran + blueberry juice (contain tannins that interfere w the pili of E. coli and prevent the binding to urinary epithelia)
What is pyelonephritis?
What does the infection often involve?
What happens if the infection is severe?
Pyelonephritis (aka a KIDNEY INFECTION) is a type of UTI that generally begins in the urthra, bladder, or sometimes in the blood, and travels to one or both of the kidneys.
The infection often involves the renal pelvis and medullary tissue - resulting in inflammation + possibly necrosis
If the infection is severe - exudate + pus compress the renal vessels, resulting in ischemia + HTN. Compression of the ureter obstructs urine fow.
What are the clinical manifestations of pyelonephritis?
- pain (dull ache in lower back / flank) r/t distension of the renal capsule
- systemic signs similar to symptoms of cystitis
- on urinalysis: leukocyte + epithelia casts, failure to concentrate urine, bacteriuria
- azotemia due to bacterial obstruction
- chronic failure if chronic or repeated infections occur
What is chronic pyelonephritis?
- Chronic pyelonephritis is a term used to describe a kidney that has become shrunken and has lost function owing to scarring or fibrosis
- Usually occurs as the outcome of recurring infections involving the upper urinary tract
What is the most common cause of urinary tract obstruction?
Urinary calculi (kidney stones) or nephrolithiasis
What is nephrolithiasis?
The process of forming a kidney stone
What are the 4 types of stone that can form in the urinary tract?
1) calcium (phosphate or oxalate)
2) struvite (Mg, ammonium, phosphate)
3) uric acid
4) cystine
What solute is found in approximately 75% of kidney stones? Why?
Calcium due to idiopathic hypercalcuria (most common), hyperparathyroidism, or immobility
Identify the contributing factors towards the development of uric acid kidney stones (10% of all stones).
- hyperuricosuria (excessive uric acid in the urine)
- gout
- chemotherapy
- obesity
- diet high in red meats + organ meats
- acidic urine
Why do struvite stones occur?
Why do cystine stones occur?
primarily because of a chronic or recurrent UTI w urea-metabolizing bacteria + alkaline urine
cystine stones are rare - usually result from inherited disorders of amino acid metabolism
Why do renal stones occur?
Renal stones occur when organic salts precipitate in the urinary tract.
Can result from saturation or due to a change in the solubility of a salt.
Identify 3 factors that favour renal stone formation
- Dehydration favours stone formation by increasing urine concentration + decreasing the Ca++ transit time.
- High Na+ and high protein diets
- HTN
What are the clinical manifestations of urinary calculi?
- lower back + flank pain due to impingement of renal capsule
- pain can radiate into groin, peritoneum, or scrotum as distension of the ureter occurs - excruciating pain called renal colic
- lower abdominal pain occurs as the stone moves into the bladder + urethra
- oliguria + hematuria
- signs of hydronephrosis + hydroureter
What is implied if kidney stones obstruct both kidneys?
Underlying renal disease
What will happen if a pt w only one kidney has kidney stones?
post-renal azotemia + anuria will result
How do we typically treat kidney stones?
- fluids, bed rest, analgesics
- thiazide diuretics for oxolate stones
- antibiotics for struvite stones
- alkali therapy for oxalate, uric acid, cystine stones
- allopurinol treatment for uric acid stones
- cellulose phosphate to chelate calcium, cholestyramine to bind oxalate
- low sodium + protein intake often prevents stone formation - decreasing calcium isn’t v/ helpful
- lithotripsy
- surgery
- nutritional therapy
What are the 2 most common causes of urinary obstruction?
renal calculi + prostate disease
What are the 2 most damaging effects of urinary obstruction?
stasis of urine - predisposes to infection
increased backpressure - can impair renal blood flow + damage renal tissue
Describe how impedance to urinary flow can lead to ischemic damage + necrosis of the kidney
impedance to urinary flow increases the pressure w/in the renal pelvis + calices which can obstruct blood flow to the medulla and cause ischemic damage + necrosis
How long does it take for irreversible nephron damage to occur r/t complete urinary obstruction? How long does recovery take once the obstruction is removed?
Irreversible nephron damage can occur w/in a few days of complete obstruction.
Recovery can take weeks
What is hydroureter? What is hydronephrosis? When do they occur?
hydroureter = dilation of the ureters
hydronephrosis = dilation of the renal pelvis
both occur w prolonged urinary obstruction
Why might abdominal distension and paralytic ileus (intestinal blockage in the absence of an actual physical obstruction) occur as a result of urinary obstruction?
due to disruption of visceral innervation which impairs GI mobility
Why is early diagnosis + treatment essential in the case of urinary obstruction?
Failure to restore urine flow can result in permanent renal damage - bilat obstruction can result in renal failure
What is benign prostate hyperplasia? What causes it?
non-malignant growth / enlargement of the prostate gland; most common benign tumor found in men
cause is unknown; hormonal factors + age play a role
What are the 2 categories of symptoms of benign prostate hyperplasia?
- mainly caused by obstruction to urine outflow + bladder dysfunction
- fall into 2 categories: irritative + obstructive
What causes irritative symptoms of benign prostate hyperplasia? What are these symptoms?
result of bladder hypertrophy + dysfunction
- frequency
- urgency
- nocturia
What causes the obstructive symptoms of benign prostate hyperplasia?
results from narrowing of the bladder neck + urethra
- difficulty initiating urination
- decreased urinary flow
- intermittency
- hesitancy
- dribbling
What are the complications associated w benign prostate hyperplasia?
- UTIs
- hematuria
- post-renal azotemia
- chronic renal failure (from bilateral hydroureter + hydronephrosis)
- bladder distention + hypertrophy
How do we usually treat benign prostate hyperplasia?
- alpha1 blockers
- androgen blockade
- prostate stents
- surgery
What is the most common cancer in males?
prostate cancer
Identify the risk factors for the development of prostate cancer
- men w first + second degree relatives w prostate cancer are at 8x the risk
- more common in men over 50 - occurs earlier in men of african descent
- elevated testosterone is believed to be a risk factor - never develops in men who have been castrated
- dietary fat + red meat
- obesity
- inactivity
What are the clinical manifestations of prostate cancer? How do we diagnose it?
- most tumors are asymptomatic; depending on the size of the tumor there may be changes in urination similar to BPH
- screening is needed for those at risk
- elevated PSA in the blood (prostate-specific antigen)
- diagnosis confirmed w prosatate biopsy
How do we treat prostate cancer?
Surgery, radiotherapy, androgen-deprivation therapy
What are the 2 types of hereditary renal diseases?
- polycystic renal disease
- medullary cystic disease
What is the primary cause of end stage renal failure in Canada?
diabetic nephropathy
Describe kidney cancer in terms of its occurrence rate in men and women and its % of all cancer deaths
kidney cancer is the 5th most common cancer in men + 11th in women
responsible for 2.5% of cancer deaths
Describe bladder cancer in terms of its occurrence rate in men and women and its % cancer deaths in men + women
bladder cancer is the 4th most common cancer in men and the 11th most common in women
responsible for 4% of cancer deaths in men and 2% in women
What are the common screening tests used to detect prostate cancer?
- serum PSA
- rectal exam (hard nodular tumors)
- ultrasound (small tumors)
Clients with chronic kidney disease experience an increased incidence of cardiovascular disease related to which of the following (select all that apply)?
- genetic predisposition
- hypertension
- vascular calcification
- increased HDLs
- increased release of EPO
- htn + vascular calcification
