LAUSR

1. The pattern of hematuria (one painless episode of macroscopic hematuria with bright red colored urine after exercise without persistent microscopic hematuria), and the finding of normal C3 complement fraction, excluded post-streptococcal glomerulonephritis from the differential diagnosis. The mild hypercalciuria observed in the first 24-h urine collection was not documented in the second urine collection 7 days after discharge (calcium excretion 0.5 mg/kg/24 h), and this was attributed to the fact that the patient was lying down during hospitalization. Nephrolithiasis was excluded from the differential diagnosis, based on absence of pain and normal ultrasound and abdominal X-ray, which failed to show a stone in the urinary tract. Other causes of macroscopic hematuria were excluded, including urinary tract infection (negative urine culture) and coagulation disorders (normal blood coagulation tests). 2. The onset of macroscopic hematuria after exercise with resolution at rest, and the exclusion of other, more common causes of hematuria, led to the most likely diagnosis of nutcracker syndrome (NCS). In order to confirm the diagnosis of NCS, Doppler ultrasonography andmagnetic resonance angiography (MRA) were performed. 3. Doppler ultrasonography revealed a reduced angle between the superior mesenteric artery and the abdominal aorta and a sharp change in the width of the left renal vein by 0.2 between the above vessels to 0.62 at the left kidney portal, findings compatible with nutcracker syndrome (Fig. 1). MRA revealed a very acute angle between the superior mesenteric artery and the aorta (about 25 degrees, with an acceptable value of 38 degrees) and dilatation of the left renal vein at about 8 mm before its intersection with the upper mesenteric artery, while after the intersection, the diameter was estimated at about 2.5 mm (Fig. 2). Scrotal Doppler ultrasonography was conducted to rule out the presence of a left varicocele vein, often coexisting with NCS [1], which was negative. The above findings and the patient’s clinical presentation were consistent with the diagnosis of NCS. 4. The patient was advised to reduce excessive exercise for 6 months and to be monitored clinically every 6 months and once a year with ultrasound and Doppler ultrasonography of the kidney and scrotum. He was not given any medication, but was advised to gain weight in order to increase retroperitoneal fat, which leads to decompression of the left renal vein due to a change in the position of the left kidney [2]. During follow-up of 10months, the patient was asymptomatic.