Renal/ Genitourinary Flashcards
What is considered a lower UTI?
Cystitis (bladder)
Urethritis (urethra)
What is considered an upper UTI?
pyelonephritis (kidney)
renal abscess
What are urinalysis diagnostic criteria for UTI? describe the importance of specificity and sensitivity for each test.
pyuria > 10 WBC
presence of nitrate by dipstick- specific, but not sensitive test for bacteriuria- if positive, this is indicative of true positive, but higher rate of false negatives.
esterase detection by dipstick- high rate of true negatives, but false positives are common
What are the 3 treatment options for uncomplicated cystitis?
- Macrobid/ Macrodantin (nitrofurantoin) 100mg BID x 5 days
- Bactrim (trimethoprim-sulfamethoxazole PO BID x 3 days
- Fosfomycin 3mg PO x1
What are the pros and cons of fosfomycin for UTI treatment?
Pro: only 1 pill, can give in the clinic and patient doesn’t need to pick up prescription
Con: expensive
What are the risks of fluroquinolones? Name a few drugs
ciprofloxacin, levaquin
Low risk of serious adverse effects: tendon rupture, aortic aneurysm rupture
Avoid in patients with vascular disease (most adults 65+) or patients with genetic conditions like Marfan and Ehlers Danlos syndrome
What are symptoms that suggest pyelonephrosis? What lab value would you order, in addition to UA?
flank pain, low back pain, fever/ chills, n/v, altered mental status in elderly
ORder: ESR- will be elevated in pyelonephritis due to inflammation occuring
How does management of upper UTI differ from lower UTI?
The treatment recommendations are the opposite. In upper UTI: avoid bactrim (high resistance) and nitrofurantoin (doesn’t reach therapeutic levels in the kidney)
Recommendation: fluoroquinolones- ciprofloxacin 500 mg PO BID - 7 days if uncomplicated, 10 if complicated
Levofloxacin- OK, but not moxifoxacin because inadequate tissue penetration
Ceftriaxone (cephalosporin)- 1 mg IV every 24 hours (14 days)- requires hospitalization or home health treatment
** if healthcare associate (CAUTI)- need antipseudomonal coverage- ampicillin and aminoglycoside (gentamycin, amikacin, tobramycin), cefepime, imipenem, meropenem, pip-tazobactam
What is renal insufficiency? What are some causes? What are symptoms?
Decreased GFR, reduced clearance of solutes; decrease in renal function. GFR naturally decreases with aging starting at age 35. This condition is beyond normal decrease of aging
Causes: hypertensive nephrosclerosis, glomerulonephritis, diabetic neuropathy, interstitial nephritis, polycystic kidney disease.
Symptoms: generally asymptomatic until late stage- GFR< 20-25% of normal
What is method to identify acute kidney injury? RIFLE
what are the creatinine changes, GFR changes and UO changes
Risk- creatinine x 1.5 or GFR > 25%, UO < 0.5mg/kg/hour for 6 hours
Injury- creatinine x2 or GFR > 50% decrease, or UO < 0.5mg/kg/hour for 12 hours
Failure- creatinine x 3 or GFR > 75% decrease, UO < 0.3 mg/kg/hour for 24 hours, or anuria for 12 hours
Loss- complete loss of kidney function > 4 weeks
End-stage kidney disease- loss of kidney function > 3 months
Define pre-renal AKI
caused by conditions that impair renal perfusion: shock, dehydration, cardiac failure, burns, diarrhea, vasodilation, sepsis
can be reversed by correcting the underlying cause of hypoperfusion- no damage to renal tubules occur if this is only considered pre-renal AKI.
Define intrarenal AKI
disorder that directly affects the renal cortex or medulla-
causes: allergy, obstruction of renal vessels (emboli or thrombus), nephrotoxic agents *** most common, blood transfusion reaction- RBC hemolyze and block nephrons.
nephron damage- tubular portion most commonly damaged- acute tubular necrosis
define post-renal AKI
urine flow obstruction
causes: mechanical - renal calculi, tumors, urethral strictures, BPH
functional causes: neurogenic bladder, diabetic neuropathy
Defining lab characteristics to distinguish: prerenal, intrarenal and post-renal AKI
prerenal: urine sodium < 20. intrarenal and postrenal >40
prerenal: spec grav > 1.015 (dehydrate), intrarenal, post renal < 1.015
prerenal: few hyaline casts, intrarenal: granular sediment - white casts
Pre-renal FENa (fractional excretion of sodium) Prerenal: < 1, intrarenal and postrenal > 3
What is FENa? which patient conditions are ineligible for this calculation
Fractional excretion of sodium. If low < 1, indicates pre-renal (kidney sodium clearance is normal) FENa is elevated in intrarenal and post-renal because kidney sodium clearance is impaired- especially intrarenal
**Do not use in patients taking diuretics or with known chronic kidney disease, urinary tract obstruction, or acute glomerular disease
What is management for prerenal?
expand intravascular volume: volume resuscitation- fluids and blood products (if indicated)
What is management for intrarenal AKI?
maintain renal perfusion- fluids, pressors, stop nephrotoxic drugs, renal replacement therapies as indicated -CRRT, dialysis
what is management for post-renal AKI ?
remove source of obstruction- foley, renal calculi, tumor, strictures, ; renal ultrasound, CT scan for diagnostic workup
What is the criteria for dialysis (AEIOU acronym)
A- acidosis metabolic
E- elevated electrolytes- hyperkalemia
I- intoxication
O- oliguria < 400 ml/ 24 hours. anuria < 100 ml/ 24 hours
U- uremia- buildup of toxins in blood because kidney is not filtering them out
What is nephrolithiasis? What are the types/ What is the incidence/ cause?
Renal calculi- kidney stones
occurs in 10% of people over their lifetime
Calcium- 80% of stones, more common in men, age of onset > 30 years. familial related
Uric acid- more common in men- associated with gout
Struvite- mainly women, result from UTIs- urease producing bacteria- “magnesium-ammonium-phosphate stones”, may grow to a large size and fill the renal pelvis and calyces
Cystine- an amino acid that is insoluble in urine, difficult to manage
what are symptoms of nephrolithiasis?
asymptomatic or pain and bleeding when passing through ureter.
acute flank pain (colic-like) - increasing intensity
radiation of pain to the groin- stone passed to lower third of ureter,
testicular pain possible
what are diagnostics and management for nephrolithiasis?
CT scan, UA, CBC, BMP
analgesia and hydration- initial treatment IV trio- 1. morphine or dilaudid, 2 Toradol IV, metoclopramide (Reglan) IV- move gut, vagus nerve stimulation can slow gut **black box warning- extrapyramidal symptoms and permanent tardive dyskinesia
IV and oral hydration with pain management
what is lithotripsy?
ultrasound shock waves use to break down large renal calculi so they can pass through ureter
What is black box warning for reglan?
can lead to permanent tardive dyskinesia.
avoid longterm use of reglan (> 12 weeks)
avoid use in parkinson’s patients- can exacerbate symptoms
What is incidence, cause and signs/ symptoms of BPH?
incidence- 50% of men > 50, 80% of men > 80
cause: unknown- possible the prostate’s response to androgen hormones over time
S/s: frequency/ dysuria/ urgency/ nocturia/ incontinence/ hesitancy/ dribbling/ retention/ starting and stopping flow
Diagnostic and management for BPH
UA: to detect infection
PSA: > 4ng/ml= abnormal - there are age specific ranges- ok to trend up as long as within age norm.
management: observe, refer to urologist
alpha blockers: terazosin, prazosin, tamsulosin- relax muscles of bladder and prostate
5 alpha reductase inhibitors- finasteride, dutasteride- shrink large prostates
saw palmetto (herbal)- may improve symptoms in some men; no evidence that it decreases prostate cancer risk
what meds worsen BPH?
benadryl, sudafed (pesudoephedrine), oxymetazoline spray (Afrin), antidepressants - SSRIs
What is a TURP?
transurethral resection of the prostate- surgery- indicated for BPH if significant urinary symptoms persist. or indicated for prostate cancer.
describe geriatric renal physiology changes
decreased GFR by 10% per decade after age 30
decreased number and size of nephrons
decreased renal blood flow, similar trend to GFR
reduced hormone response to vasopressin, impaired ability to conserve sodium- increased risk for dehydration
bladder tone, elasticity and capacity decreased
increased urine residual and frequency, increased nocturnal urine production
BPH- men
what is normal creatinine clearance range in adults?
what is creatinine clearance formula adjustment for elderly?
adults: males 97-137mL
females: 88-128mL
values decrease as one ages- by 6.5 ml/min for every 10 years after age 20
Elderly:
140- age (years) x body weight (kg) x (0.85 for women)/ 72 x serum creatinine
What are the bugs that are common for UTIs? gram neg, gram pos…
Gram neg: E. coli (most common), Pseudomonas aeruginosa
Gram pos: enterococci, coagulase negative staphylococci, streptococcus agalactiae, S. aureus
Fungi- especially in patients with foley catheters
What are the atypical UTI symptoms - common in elderly?
incontinence, lethargy, decreased appetite, dehydration, confusion
When is it indicated to treat asymptomatic bacteriuria?
pregnancy, patients undergoing urologic intervention, renal transplant patients
- multiple organisms often present
- often occurs in elderly
