General Surgery and Urology – Kidney and Ureter MCQs (Part 2)

Dietl’s Crisis
• Intermittent hydronephrosis (Dietl’s crisis): A swelling in the loin is associated with acute renal pain.

Some hours later the pain is relieved and the swelling disappears when a large volume of urine is passed

• The severity and colicky nature of ureteric colic pain is caused by the hyperperistalsis and spasm of smooth muscles of the ureter as it attempts to rid itself of a foreign body or to overcome obstruction.

Pain from Acute Obstruction of Ureter (Stone or Blood clot)

• Ureteral pain is typically stimulated by acute obstruction (passage of a stone or a blood clot)

•Back pain from renal capsular distention combined with severe colicky pain (due to renal pelvic and ureteral muscle spasm that radiates from the costovertebral angle down toward the lower anterior abdominal quadrant, along the course of the ureter.

• The severity and colicky nature of this pain are caused by the hyperperistalsisQ and spasm of this smooth muscle organ as it attempts to rid itself of a foreign body or to overcome obstruction.

Stone in the upper ureter:

• Pain radiates to the testicle.
• Since the nerve supply of this organ is similar to that of the kidney and upper ureter
(T11–12)

Stone in the middle ureter:

• Pain is referred to McBurney’s point and simulate appendicitis on right side.
• Left side, it may resemble diverticulitis or other diseases of the descending or
sigmoid colon (T12, L1).

Stone in the lower ureter:

• Pain is referred to inner side of thigh or scrotum or perineum (L1, L2).

Stones at the level of orifice:

• Symptoms of vesical irritability such as frequency and urgency may occur.

Renal Calculi
Laboratory Investigations:
• Urine: pH, microscopic examination (RBCs, pus cells and crystalluria) and culture for splitting organisms.                                                                                                                          • Acidic urine: CCU (Calcium oxalate, Cystine, Uric acid).
• Alkaline urine: Calcium Phosphate, Struvite.

Radiographic Investigations:
• X-ray KUB:
− 90% are radiopaque
− Radiolucent stones (TIXU): Triamterene, indinavir, xanthine and uric acid
• USG: A screening tool for hydronephrosis or stone within collecting system.
• IVP:
− Early films (At 1 and 5 min for promptness of contrast excretion and Any obstruction along urinary tract)
− Delayed films (Identifies cause of delayed contrast excretion)

• Non-contrast spiral CT is the most sensitive investigation for renal/ureteric calculus.

• Retrograde pyelogram (RGP):
− Better delineation of anatomy. Especially useful if distal ureter not visualizedQ well.
− Excludes unsuspected additional ureteric calculi and allows assessment of coexistent ureteric disease such as stricture, which may complicate the operative and post operative course.

Radionuclide evaluation:
• DMSA (Dimercaptosuccinic acid): Renal morphologyQ (scar)
• DTPA (Diethylene Triamine Pentacetic Acid): To assess perfusion (Effective renal plasma flow) and functionQ (Total and differential GFR), less effective than MAG-3 for decreased renal function
• MAG-3 (Mercapto-acetyl glycine): Best for renal perfusion(Assess renal plasma flow).

• Metabolic workup should be done in young patients, with recurrent calculi, multiple calculi and inephrocalcinosis, struvite stones, uric acid stones and cystine stones.

Oxalate Stones:
• Oxalate stones are irregular in shape and covered with sharp projections, which tend to cause bleeding.
• The surface of the calculus is discolored by altered blood.
• A calcium oxalate monohydrate stone is hard and radiodense.