Nephrolithiasis
Pt with h/o low fluid intake, congenital kidney deformity, primary hyperthyroidism, and DM/gout due to excess sweetened beverage consumption presents with acute onset, paroxysmal flank pain. Flank pain is unilateral and episodes of severe pain generally last 20-60 minutes. ROS positive for N/V, dysuria, and urinary urgency. Reports personal h/o malabsorptive bariatric surgery and family h/o nephrolithiasis. Severe, unilateral CVA tenderness on exam.
Pregnancy test negative
Microscopic hematuria on urinalysis
Low-dose CT with contrast shows hydronephrosis, presence of stone
Stone <10 mm
Administer indomethacin 75 mg BID, tamsulosin 0.4 mg daily, and strain urine with voids
Consult urology if pt requires hospitalization or stone does not pass within 3 weeks in the outpatient setting
Stone >10 mm: Administer ketorolac 15 mg q6 hours and consult urology
Pt advised to keep stone upon passage
Send stone for analysis
Notes
Kidney stone types
Calcium stones (80%)
Calcium oxalate: More common and increased risk with malabsorptive bariatric surgery, e.g. Roux-en-Y
Calcium phosphate: Less common than calcium oxalate
Struvite (magnesium ammonium phosphate)
Uric acid
Cysteine
Differential diagnosis to consider
Ruptured aortic aneurysm
Microscopic hematuria may be present
Verify stable BPs to rule out diagnosis
Ectopic pregnancy
Rule out with pregnancy test
Consider pelvic ultrasound if pregnancy test is positive
Other gynecologic issues can also be ruled out with ultrasound, e.g.
Ruptured ovarian cyst
Ovarian torsion