13. Renal, Urinary Systems & Electrolytes Flashcards
Fever, tinnitus, and tachypnea should make you suspicious of ____ intoxication. What acid-base disorder is associated with it?
Aspirin intoxication
Mixed respiratory alkalosis AND AG metabolic acidosis
What is initial treatment for severe hypercalemia (sx: weakness, GI distress, neuropsych sx) ?
- Saline hydration to restore intravascular volume (patients typically vol-depleted due to polyuria and dec oral intake)
- Calcitonin - inhibit bone resorption
Note: bone marrow bx can be done after hydration if multiple myeloma (pancytopenia) is suspected
When should you image for possible pyelonephritis?
patients with persistent clinical sx despite 48-72h of therapy for UTI
Patients with nephrotic syndrome are at risk for developing what?
Hypercoagulable state –> Venous or arterial thrombosis (renal vein thrombosis most common).
Other complications of nephrotic synd: protein malnutrition, Fe-resistant microcytic anemia, vit D def
What is the fluid of choice in a patient with severe hypovolemic hypernatremia?
Isotonic solutions (normal saline) aka 0.9% saline Na must be returned to normal slowly. When giving IV fluid boluses, only isotonic solutions should be used (eg normal saline or lactated Ringers)
Acute urinary incontinence in elderly patients may have typical presentations. Consider reversible etiologies first, esp if new onset (remember: DIAPERS). What does it stand for?
Delirium Infection (UTI - acute infx are leading cause of UI in elderly) Atrophic urethritis/vaginitis Pharmaceuticals (a blockers, diuretics) Psychological Excess urine output Restricted mobility Stool impaction
What is the most common form of glomerulopathy assoc with HIV?
Focal and segmental glomerulosclerosis - nephrotic range proteinuria, azotemia, normal sized kidneys
Large amount of blood on UA with relative absence of RBCs on urine microscopy should make you suspect what?
Rhabdomyolysis - can lead to acute renal failure
What is a risk factor for recurrent cystitis in toddlers? MOA?
Chronic constipation
MOA: impacted stool distends rectum –> compresses bladder –> prevents complete voiding –> urinary stasis
What is the primary intervention proven to slow the decline in GFR once azotemia develops in patients with diabetic nephropathy?
intensive blood pressure control. Target BP of 140/90
Target is 130/80 if diabetic with signs of nephropathy
ACEI and ARBs are the preferred antihypertensives
Dietary recommendations for patients with renal calculi to dec stone formation?
Inc fluid intake, dec sodium intake, normal dietary calcium intake.
How can nitro cause cyanide poisoning? Sx?
Cyanide binds to cytochrome oxidase and inhibits mito oxid phosphorylation. Cells shift to anaerobic metabolism –. dec ATP –> lactic acidosis.
Sx - HA, confusion, arrhythmias, tachypnea, vomiting, flushing
How can you differentiate hematuria due to glomerular vs non-glomerular causes
Glomerular: urine studies show proteinuria, dysmorphic RBCs or RBC casts
Non-glomerular: gross hematuria, normal looking RBCs, no signif proteinuria.
Rupture of what part of the bladder causes urine to leak into the peritoneal cavity and can lead to chemical peritonitis?
Dome of the bladder - The superior and lateral surfaces of the bladder are bordered by the peritoneal cavity
Can caused refered pain to the shoulder.
What should you suspect in a patient with palpable purpura, proteinuria, hematuria, arthralgias, peripheral neuropathy, hypocomplementemia, and hx of hep c?
Mixed cryoglobulinemia.
Why should patients with severe hypercalcemia be given saline hydration aggresively?
Pts typically vol depleted due to polyuria (hypercalcemia-induced nephrogenic DI) and dec oral intake.
Calcitonin: inhibit bone resorption
Bisphosphonates: reduce ca levels
Hyponatremia due to primary polydipsia is more common in pts with psych conditions. Urine osmolality is in what range?
<100mOsm/kg
Note: >290mOsm/kg indicates marked hyperglycemia or advanced renal failure as the cause of hyponatremia
Pt w/hx of total nephrectomy presenting with flank pain, poor urine output, intermittent episodes of high-vol urination is due to what?
Urinary outflow obstruction due to renal calculi
patients with pyelo who vomit, are old, septic, or have comorbidities require hospitalization and IV therapy. When can these patients be switched to culture-guided oral abx if sx improve?
48 h
What is the most beneficial long-term management of stress incontinence?
Urethral sling surgery
Note: pelvic mm exercises are the first-line tx option for stress urinary incontinence due to urethral hypermobility.
Patients with severe liver cirrhosis, acute renal failure, very low urine sodium, and bland urine sediement (no RBC, casts or protein) that does not improve with IVF should be suspected of having what?
Hepatorenal syndrome
- cirrhosis –> inc NO –> systemic vasodilation –> dec PVR and BP –> renal hypoperfusion
In uncomplicated cystitis in an otherwise healthy patient with positive urinalysis should be managed how?
Oral TMP/SMX, nitro, or fosfomycin
Don’t need to do urine culture unless initial therapy fails
How do you differentiate lithium-induced nephrogenic DI from psychogenic polydipsia in a psych patient?
Both: euvolemia and polyuria
DI: HYPERnatremic
Psychogenic polydipsia: HYPOnatremic
Note: urine osm <300mOsm = complete DI. Greater = partial DI
Acute pyelo with labs showing urinary alk (pH>8) raises suspicion for what bacteria?
Proteus (most common) - urease-producing org –> struvite stones
or klebsiella
