E. Pisani

Increase in the Prevalence of Symptomatic Upper Urinary Tract Stones during the Last Ten Years

Purpose: In industrialized countries the prevalence of upper urinary tract stones has continually increased during the 20th century, but there are considerable differences between countries and also within the same country. To study whether there is still an increase in the frequency of renal stones, an investigation was undertaken to determine the prevalence of stone formers in a village near Milan, Italy, during two time periods, with an interval of 12 years.Materials and Methods: Questionnaires were administered in 1986 and 1998 to all adult (age >25 years) occupants of two random samples of households in the village. Participants were asked whether they had experienced a kidney stone during their lifetime.Results: The overall prevalence of stone formers among males was 6.8% in 1986 and 10.1% in 1998; that among females was 4.9% in 1986 and 5.8% in 1998. In all age classes, the respondents in the 1998 survey more frequently reported a history of stones than in 1986, but the prevalence of renal stones was significantly higher in 1998 than in 1986 only among males aged 31–40 and 51–60 years. The yearly incidence was estimated at 0.4%, with 0.6 and 0.18% in men and women, respectively.Conclusions: This marked increase in renal stones could be the result of environmental factors such as dietary habits and lifestyle, in particular the influence of an increased consumption of animal protein should be considered.

A STUDY OF DIETARY CALCIUM AND OTHER NUTRIENTS IN IDIOPATHIC RENAL CALCIUM STONE FORMERS WITH LOW BONE MINERAL CONTENT

PURPOSE Patients with calcium renal stone are reported to have lower bone mineral density. The state of bone density in patients with renal stones have different explanations but the role of nutritional factors seems to be crucial. A group of 48 consecutive male calcium renal stone formers was studied to investigate the relationship between bone density and dietary intake. MATERIALS AND METHODS Patients completed a dietary diary for a 3-day period during normal diet. Nutrients and calories were calculated by food composition tables using a computerized procedure. Bone densitometry was assessed at the lumbar spine and femoral neck, and expressed as Z score. A blood sample was collected and was analyzed for serum biochemistry including alkaline phosphatase, parathyroid hormone and 1,25 vitamin D. A 24-hour urine sample was analyzed for calcium, phosphate, oxalate, citrate and other electrolytes. RESULTS Dietary calcium intake was significantly lower (p < 0.01) in patients with low than in those with normal bone mineral density. There was no difference in serum parathyroid hormone levels, phosphate and alkaline phosphatase between the 2 groups. The results suggest that some renal stone formers seem to be unable to decrease renal excretion of calcium on a low calcium diet leading to a negative calcium balance. CONCLUSIONS A primary abnormality of bone metabolism could be a reasonable explanation of reduced bone density observed in renal stone formers on a low calcium diet since serum parathyroid hormone levels are in the normal range. From a therapeutic point of view these data confirm that restriction of dairy products in renal stone formers should be avoided.

Evaluation of Urinary Level of NMP22 as a Diagnostic Marker for Stage pTa-pT1 Bladder Cancer: Comparison with Urinary Cytology and BTA Test

Background: In the present study we compared the clinical value of two new specific tests for transitional cell carcinoma, urinary nuclear matrix protein (NMP22) levels and bladder tumor antigen (BTA) test, with that of urinary cytology in the follow-up of patients with superficial bladder cancer. Materials and Methods: Hundred and five bladder cancer patients were recruited: 30 stage pTa and 45 stage pT1 (group A), and 30 with a history of bladder cancer but no recurrence at the time of the study (group B). Urine samples were collected before any instrumental manipulation of the genitourinary tract. All patients were negative for urinary tract infections at conventional urine analysis. Results: NMP22 at a cutoff value of 6 U/ml showed a sensitivity of 83.3% in pTa cases and 97.7% in pT1 cases, with a false-positive rate of 23.3%. The BTA test was positive in 26.6% of patients with cancer stage pTa and in 66.6% of pT1 stage, with 30% false-positives in the non-neoplastic group. Urinary cytology, performed on three consecutive samples, was positive in 20% of patients with cancer stage pTa and in 64.4% of pT1 stage and did not show any false-positive cases. Stratifying the neoplastic patients according to lesion grade, NMP22 (at a cutoff value of 6 U/ml) was positive in 86.2% of G1, 97.2% of G2 and 90% of G3. BTA was positive in 37.9, 52.7 and 70% of G1, G2 and G3, respectively, while urinary cytology was positive in 37.9, 44.4 and 80%.

Renal tubular damage after renal stone treatment.

Summary50 patients were studied with respect to renal tubular damage related to open operative, percutaneous and extracorporeal shock wave treatment of renal stones. Preoperative and postoperative urinary N-acetyl-glucosaminidase (NAG) levels were measured as a marker of renal damage. There was no significant evidence of renal tubular damage in patients who underwent a conventional or percutaneous nephrolithotomy; urinary NAG excretion was significantly increased after ischaemic surgery. After extracorporeal shock wave lithotripsy (ESWL) serum NAG levels increased, probably because a damage of the white blood cells in cutaneous and renal circulation, but a slight increase of urinary NAG excretion could suggest a mild renal tubular damage especially in case of more than 2,000 shocks.

Familial Aggregation of Renal Calcium Stone Disease

The question of a familial predisposition towards stone formation in primary nephrolithiasis has not been explored completely. In a sample of 214 calcium stone patients, and 428 age and sex-matched controls we observed a higher frequency of stones among the first degree relatives of stone patients compared to the relatives of controls. A family history of renal stones was more common among the female (45 per cent) than among the male patients (31 per cent). There was no relationship between family history of renal stones, and abnormal calcium and oxalate excretion rates. A significant association between a family history and a higher urinary pH was observed among the female calcium stone patients. A genetic defect in urinary acidification with variable expressivity might be associated with a high frequency of stone formation. Moreover, uric acid excretion was higher in male stone patients with a family history of stones. Finally, the parents and siblings of the renal stone patients were affected more by calculi than were the corresponding relatives of their spouses.

Secretory immunoglobulin A and inhibitory activity of bacterial adherence to epithelial cells in urine from patients with urinary tract infections

SummaryTo assess the role of local immune response against bacterial invasion of the urinary tract we studied 168 patients with bacteriuria. Urinary secretory immunoglobulins A (sIgA) were measured using radial immunodiffusion or enzyme-linked immunosorbent assay (ELISA). In particular, ELISA is a very suitable assay for measuring the low levels of sIgA in urine. Furthermore, we used a quantitative in vitro adherence assay to investigate the attachment of Escherichia coli to human uroepithelial cells after incubation in urine from patients with urinary tract infection. Urine from patients with ileocystoplasty was significantly more potent in inhibiting bacterial adherence than was urine from other groups of patients with urinary tract infection. The presence of high urinary sIgA may help explain the increased antiadherence activity of urine in patients with ileocystoplasty. Mean urinary sIgA in patients with upper urinary tract infection was higher than in patients with uncomplicated infection in the lower urinary tract. Alterations in mucosal immune functions may account for the propensity toward bacterial colonization in women prone to uncomplicated urinary tract infection.

Urinary NAG excretion after anesthesia-free extracorporeal lithotripsy of renal stones: a marker of early tubular damage

SummarySecond generation lithotripters require a higher number of shocks per session as well as an increased rate of secondary treatments for complete stone disintegration compared to the original spark gap lithotripter. The clinical relevance of biological side effects caused by such treatment are less known. We evaluated urinary excretion of N-acetyl-glucosaminidase (NAG) before and after lithotripsy in 50 patients treated with a low pressure spark gap lithotripter (Dornier HM3) and in 36 patients treated with a piezoelectric lithotripter (Wolf Piezolith 2200) in an attempt to evaluate their side effects on renal tissue. The urinary excretion of NAG increased after both spark gap lithotripsy using the modified HM3 and piezoelectric lithtripsy. These changes may be associated with slight tubular damage that would occur after anesthesia-free lithotripsy in patients subjected both to a high number of shocks and to secondary treatments.

RENAL AUTOTRANSPLANTATION FOR COMPLETE URETERAL AVULSION FOLLOWING LUMBAR DISK SURGERY

A 29-year-old man who had undergone spinal surgery for disk disease 2 weeks earlier was admitted to the hospital because of abdominal pain with low grade fever. Physical examination revealed abdominal tenderness in the left quadrants. Marked leukocytosis (white blood count was 21,500/ mm., normal 4,300 to 10,000) was noted. Renal sonography showed a left kidney with no abnormalities, while computerized tomography (CT) revealed a large left retroperitoneal urinoma extending from the kidney to the iliac vessels (fig. 1). On excretory urography (IVP) the ureter was not seen below the L4 to L5 level (fig. 2). Cystoscopy with retrograde pyelography demonstrated extravasation of contrast medium at the same level. Retrograde and antegrade placement of a stent failed. Surgical exploration was performed via a flank incision and a urinoma more than 2 l. was drained. Complete avulsion of the ureter in its upper third was found. The laceration was greater than 5 cm. with badly damaged ureteral edges. Downward displacement of the kidney was used to close the gap, an indwelling ureteral stent was placed and apposition of the edges of the ureter was obtained with adventitial sutures. Further drainage was provided with nephrostomy. At 3-month followup after stent removal antegrade ureter-

Robotized prostate biopsy

SummaryThe authors describe their experience about a robotic system designed to perform prostatic biopsies, locally and tele-controlled. The system employs an industrial robotic arm with four degrees of freedom made up of a biopty gun and 18 gauge biopty needle. An ultrasound scanner with a trans-rectal probe 7.5 MHz is necessary to localize the target area into the prostate. A telemetric system allows one to plot the position of the ultrasound probe by video cameras mounted on the robot support and three infrared lights mounted on an ultrasound probe and the coordinates (roll, pitch, yaw) are converted into robot coordinates from a computer controller. A tele control is possible too through a remote control station connected with the local station by an ISDN telephone line. Experimental tests proved a precision of 2 mm from the target point when the test has been executed in the predetermined working area. After the authorization of the Ethical Committee of the University of Milan, a clinical test has be...

Laparoscopic renal cyst excision

SummaryRenal cystic failure generally does not require any form of treatment except in cases where a secondary obstruction of the excreting tract occurs, for persistent hypertension, when symptomatic pain persists or is complicated by infection or haemorrhage. Laparoscopic treatment of a renal cyst has proved to be a safe and efficacious therapy. We report our transperitoneal and retroperi-toneal experience with laparoscopic resection of simple renal cysts, between January 1992 and June 1995. We employed a transperitoneal approach for 10 patients and in eight cases a retroperitoneal access. No intraoperative complications were encountered in this series. In all patients blood loss was less than 100cc. With both approaches patients can be discharged between 24 and 72 h after the operation. At 6 month follow up, one recurrence was observed in the group of patients treated transperitoneally. Retroperitoneoscopy seems to be safer and easier compared to the transperitoneal technique.