Flashcards in 25 - Urology Case Study Deck (78)
Case study 1
A 56 year old male presents to the emergency department with 2 hours of excruciating pain in the right flank and groin radiating into the scrotum
He has had associated nausea and vomiting.
No fever or chills
He had a few twinges of less severe pain over past 2 months
At time of exam he is very anxious, writhing, unable to find comfortable position
Describe the workup of case study 1
Exam: Right costovertebral angle tenderness, Mild RLQ tenderness, Abdomen is not rigid, no guarding or rebound tenderness, No testicular mass or tenderness
Blood work: CBC, BMP normal
UA shows moderate blood with many RBCs, No sign of UTI
Imaging: Noncontrast CT abdomen/pelvis
What is on your differential diagnosis?
- Renal or ureteral stone
- Hydronephrosis (ureteropelvic junction obstruction, sloughed papilla)
- Bacterial cystitis or pyleonephritis
- Acute abdomen (bowel, biliary, pancreas or aortic abdominal aneurysm sources)
- Gynecologic in females(ectopic pregnancy, ovarian cyst torsion or rupture)
- Radicular pain (L1 herpes zoster, sciatica)
- Referred pain (orchitis)
Describe the CT results
- Stone stuck in the ureter
- Kidney is dilated
What are urinary calculi?
- Kidney stones are solutes that occur in amounts too high to stay dissolved (supersaturated) in urine
Solutes precipitate and aggregate to form concretions or stones
What is the most common composition of stones?
What are the other compositions of stones?
From most to least common
- Uric acid
- Struvite (magnesium ammonium phosphate)
- Calcium phosphate
Describe the gold standard imaging protocol for a suspected stone
- CT is best imaging modality to detect urinary calculi. Detects over 96% of stones (study of choice *****)
What are some other imaging options for a stone?
- KUB x-ray may detect 70-80% of stones but may miss smaller calculi. Overlying bowel gas can obscure visualization
- Intravenous urogram (IVU) commonly was utilized prior to wide spread use of CT. Detects up to 80-90% of stones but more time consuming.
- Renal ultrasound (US) can detect most intrarenal stones and hydronephrosis, but not sensitive for ureteral stones. Study of choice for suspected stone in pregnant women
What happens in the first 2 hours of having a renal obstruction
- Increased renal pelvic pressures
- Increased renal blood flow
- As renal pelvic pressure increases, glomerular filtration (GFR) decreases
This back flow pressure and stretching is what hurts like crazy
What happens at 6-24 hours after developing a renal obstruction?
- Renal pelvic pressures remain elevated
- Renal blood flow diminishes
What happens at more than 24 hours after developing a renal obstruction?
- Renal pelvic pressures trend down towards baseline (but remain elevated)
- Renal blood flow continues to diminish.
- If persistent, the obstruction (high grade complete obstruction) leads to renal ischemia and permanent damage typically occurs within 2 weeks
What should you note about this timeline of renal obstruction?
The pattern of pain tends to increase and decrease
The stone will get stuck, cause pain, but then move or rotate and decrease the blockage (incomplete block)
What is the expectant management when trying to allow a stone to pass?
- 2/3 of ureteral stones will pass within 4 weeks of symptom onset
- Complete obstruction is rare so risk of renal deterioration from observation is low
- Strain urine for stone passage
- Medical expusion therapy (Alpha blockers, Calcium channel blockers, NSAIDS)
- Oral stone dissolution (Uric acid stones only, urinary alkalization, potassium citrate, sodium bicarbonate)
What are indications for urgent intervention for urinary stones?
- Obstructed upper tract with infection
- Impending renal deterioration
- Pain refractory to analgesics
- Intractable nausea/vomiting
What are the surgical stone interventions?
- Extracorporeal Shock Wave Lithotripsy (ESWL)
- Ureteroscopy +/- laser lithotripsy
- Percutaneous Nephrolithotomy (PCNL)
- Open or laparoscopic lithotomy
Describe Extracorporeal Shock Wave Lithotripsy (ESWL)
- 4-15 mm stones in kidney or proximal ureter
- Stone must be radio-opaque
Describe Ureteroscopy +/- laser lithotripsy
All stones amendable but large renal stone treatment is tedious
Describe Percutaneous Nephrolithotomy (PCNL)
- Renal calculi >15-20 mm
- More invasive and requires hospital observation
Describe Open or laparoscopic lithotomy
- Most invasive
- Rarely necessary
How can you prevent stone formation?
- ADEQUATE HYDRATION!! (2.5-3 L/DAY) *******
- Dietary modifications
- Full metabolic evaluation for patients with recurrent stones or strong family history
Describe the dietary modifications
- Low animal protein, low sodium, low oxalate diets
- Normal dietary calcium
- Citrate therapy
Describe the full metabolic evaluation
- Serum chemistries
- 24 hour urine collection
- Medications and additional therapies directed at metabolic abnormalities
- A 63-year old male presents with complaint of weak urinary stream, increased urinary urgency, and nocturia x 4.
- He complains he is always tired due to lack of sleep from his nocturia.
- No UTIs or gross hematuria
- No abdominal or flank pain
Describe the work up for case 2
- Abdomen is soft, nontender, bladder is not palpable
- Phallus is circumcised, no lesions, no testicular mass
- Prostate is moderately enlarged, nontender, symmetric with no nodules
UA shows no blood or infection
PSA 2 (normal
What is on your differential diagnosis at this point?
- Benign prostatic hyperplasia
- Overactive bladder
- Prostate cancer
- Bladder cancer
- Urethral stricture
- Bladder or urethral calculus
What are the two types of lower urinary tract symptoms (LUTS)?
- Irritative (storage)
- Obstructive (voiding)
What are the irritative (storage) symptoms?
What are the obstructive (voiding) symptoms?
- Weak stream
- Terminal dribbling
- Sensation of incomplete bladder emptying