Hyeon Hoe Kim

Laparoendoscopic single-site and conventional laparoscopic adrenalectomy: a matched case-control study.

PURPOSE The purpose of this study was to describe our initial clinical experience and assess the feasibility of laparoendoscopic single-site surgery (LESS) in the treatment of benign adrenal adenoma. PATIENTS AND METHODS Nine patients undergoing LESS adrenalectomy for benign adrenal adenoma were compared with 17 patients undergoing conventional laparoscopic adrenalectomy. Controls were matched for age, sex, surgical indications, and tumor size via a statistically generated selection of all conventional laparoscopic adrenalectomies performed during the same period of time. RESULTS No significant differences in the mean operative time (169 vs. 144.5 minutes, p = 0.287), blood loss (177.8 vs. 204.7 mL, p = 0.792), and postoperative hospital stay (3.2 vs. 3.5 days, p = 0.525) were observed between the LESS and conventional laparoscopy group. However, postoperative pain, as measured by the number of days of intravenous (IV) patient controlled anesthesia use, was significantly lower in the LESS group (0.9 vs. 1.9 days, p = 0.047). Perioperative complications were similar between the two groups. CONCLUSIONS LESS adrenalectomy for benign adrenal adenoma is comparable to the conventional laparoscopic approach with regard to the operative time, blood loss, length of hospital stay, and degree of complication, and has demonstrated more desirable cosmetic outcomes.

Characteristics of bacterial colonization and urinary tract infection after indwelling of double-J ureteral stent

OBJECTIVES To investigate the natural history of bacterial colonization on the stent and in the urine after different periods of indwelling ureteral stent placement. METHODS A total of 57 double-J stents from 52 patients (21 men and 31 women, mean age 52 years, range 20 to 79) were examined. In all patients, short-term (2 to 3 days) antimicrobial therapy was administered at the time of stenting. Regular urinalysis and urine culture were performed until the stent was removed. The stents were removed by aseptic manipulation, and the proximal and distal tip segments of the stents were obtained. Three culture specimens were acquired from each stent segment (inner surface washing suspension, outer surface washing suspension, and from the stent tip itself). RESULTS Bacterial colonies were found in 44% (25 of 57) of the stents. Of the multiple pathogens identified, Enterococcus species (6 of 25) was the most common, followed by Escherichia coli (5 of 25). After short-term antibiotic prophylaxis, the bacteria did not colonize within the first 2 weeks of stent placement. However, the colonization rate increased as the duration of the stent placement lengthened. Colonization of the stent was followed by colonization of the urine. CONCLUSIONS The results of our study demonstrated that bacterial colonization at the stent began 2 weeks after indwelling stent placement and that stent colonization preceded urine colonization. The rate of colonization increased with longer periods of stenting.

Laparoendoscopic Single-Site Nephrectomy Using a Homemade Single-Port Device for Single-System Ectopic Ureter in a Child: Initial Case Report

A 3-year-old girl with a history of continuous urinary incontinence was found to have a right single-system ectopic ureter. She underwent laparoendoscopic single-site nephrectomy without any intraoperative or postoperative complications. To the best of our knowledge, this is the first case report of a laparoendoscopic single-site nephrectomy for single-system ectopic ureter in a child.

Accuracy of bladder volume determinations by ultrasonography: are they accurate over entire bladder volume range?

OBJECTIVES To investigate the accuracy of a portable three-dimensional hand-held BladderScan (BS) and two-dimensional conventional ultrasonography (CUS) in the estimation of bladder volumes. METHODS The bladder volume of 65 subjects was measured during filling cystometry using two ultrasound modalities. Serial measurements were performed when the infused volume reached 100, 200, 300, and 400 mL; the investigator measured the volumes three times each with BS and CUS. Each corresponding true volume was calculated by interpolation using zero volume and the final catheterized volume at the end of cystometry. The accuracy of the two ultrasound methods was compared using raw scaled values of the volumes and the percentage of differences of volume. RESULTS Bladder volumes determined by CUS and BS were underestimated by 21.8% and 3.3% (mean values), respectively. The percentage of differences of volume of BS was not statistically significant (P >0.05), but that of CUS was statistically significant (P <0.00001). No significant percentage of differences of volume change according to the volume status was observed by either ultrasound measurement method (P >0.05). Linear regression analysis between the true volumes and the raw scaled volumes showed that the slope of the BS was closer to 1.0 than that of the CUS, and the difference was statistically significant (P <0.001). The effects of diagnosis, age, sex, and body mass index were not significant in determining the bladder volume by either method (P >0.05). CONCLUSIONS Our results demonstrated that a three-dimensional hand-held scanner measures the bladder volume in a reproducible and accurate manner for a wide range of bladder volumes and is superior to two-dimensional stationary ultrasonography.

Urinary oxalate levels and the enteric bacterium Oxalobacter formigenes in patients with calcium oxalate urolithiasis

OBJECTIVES We performed a prospective study to evaluate the intestinal colonization of Oxalobacter formigenes and its relationship with urinary oxalate levels in patients with calcium oxalate stone disease. METHODS One hundred and three patients with calcium oxalate urolithiasis, ranging in age from 21 to 73 years (mean age, 47 years) who were followed from August 2000 to September 2001 participated in this study. Fresh stool and 24-hour urine samples were collected. Genus specific oligonucleotide sequences corresponding to the homologous regions residing in the oxc gene were designed. In order to quantify O. formigenes in clinical specimens, a quantitative-PCR-based assay system utilizing a competitive DNA template as an internal standard was developed. Urine volume, pH, creatinine, oxalate, calcium, magnesium, phosphate, citrate and uric acid were measured. RESULTS Intestinal Oxalobacteria were detected in 45.6% (n=47) of calcium oxalate stone patients by PCR. In stone formers who tested negative for Oxalobacteria, the average urinary oxalate level was 0.36 mmol/day, and this compared to 0.29 mmol/day for those patients that tested positive for Oxalobacteria (p<0.05). Mean colony forming units per gram of stool of all patients was 1.1 x 10(7) (0-4.1 x 10(8)), and the level of 24 hours urine oxalate significantly decreased with increasing level of colony forming units of O. formigenes (r=-0.356, p=0.021). CONCLUSION Our results support the concept that O. formigenes is important in maintaining oxalate homeostasis and that its absence from the gut may be the risk of calcium oxalate urolithiasis.

Comparison of laparoendoscopic single-site radical nephrectomy with conventional laparoscopic radical nephrectomy for localized renal-cell carcinoma.

PURPOSE To compare the results of laparoendoscopic single-site (LESS) radical nephrectomy with conventional laparoscopic radical nephrectomy for localized renal-cell carcinoma (RCC). PATIENTS AND METHODS This study was designed as a matched case-controlled study from our institutes RCC database. Nineteen consecutive patients who were undergoing LESS radical nephrectomy were compared with 38 patients who were undergoing conventional laparoscopic radical nephrectomy. The matching process accounted for sex, age, operative side, and tumor size. RESULTS No significant differences were observed in mean operative time (190.8 vs 172.4 min, P = 0.249), estimated blood loss (143.2 vs 199.5 mL, P = 0.235), and complication rate (15.8% vs 21.1 %, P = 0.635) between the LESS and conventional laparoscopy groups. Postoperative hospital stay after LESS radical nephrectomy was 2.7 (2-4) days, compared with 3.9 (3-7) days in the conventional laparoscopy group (P < 0.001). Postoperative pain, as measured by visual analog scale at postoperative day 1 (4.7 vs 5.8 points, P = 0.001), 2 (3.4 vs 4.6 points, P < 0.001), and 3 (2.7 vs 4.0 points, P = 0.008) was significantly lower in the LESS group. CONCLUSION LESS radical nephrectomy is a feasible and safe surgical option for localized RCC that demonstrates improved cosmetic outcomes and the additional benefits of decreased postoperative pain and decreased hospital stay.

The feasibility of laparoendoscopic single-site nephrectomy: Initial experience using home-made single-port device

OBJECTIVES To report our early experience with laparoendoscopic single-site (LESS) nephrectomy using home-made single-port device for benign nonfunctioning kidney. METHODS A total of 14 patients with benign nonfunctioning kidney underwent transperitoneal LESS nephrectomy by 2 experienced laparoscopic surgeons. The indications for nephrectomy were nonfunctioning kidney associated with ectopic kidney (n = 2), ureteropelvic junction obstruction (n = 5), genitourinary tuberculosis (n = 4), ureter stone (n = 2), and ureter stricture (n = 1). RESULTS All procedures were completed successfully. The mean operative time was 151 (85-230) minutes, estimated blood loss 108 (negligible-500) mL, and postoperative hospital stay 3.1 (2-6) days. There were no major complications. CONCLUSIONS LESS nephrectomy is a feasible and safe surgical option for benign nonfunctioning kidney.

Prevalence and epidemiologic characteristics of urolithiasis in Seoul, Korea

OBJECTIVES To study the epidemiologic details of urolithiasis in Seoul, Korea. The prevalence of urolithiasis varies by different regions in the world and has been reported to be 4% to 15%. METHODS A total of 2643 persons 40 to 79 years old living in Seoul were selected by stepwise random sampling. Questionnaires were used and completed by trained interviewers concerning whether the subjects had experienced urinary stone disease at any time in their life. RESULTS Of 2643 persons interviewed, 65 experienced 78 episodes of urinary stone formation in their lifetime. Calibrated after the Seoul population census, the overall standardized lifetime prevalence rate was estimated to be 3.5%, 6.0% in men and 1.8% in women. The point prevalence rate was estimated to be 0.9%, 1.9% in men and 0.3% in women. Most of the urinary stone diseases were diagnosed at the fifth decade. Kidney stones in family members were present in 8.1% of patients with stones and 4.1% of stone-free control individuals. Twenty percent of the patients with stones experienced recurrences. CONCLUSIONS In this first systematically assessed epidemiologic survey about the rate of urolithiasis in Korea, 6.0% of Korean men and 1.8% of women are expected to experience urinary stone disease during their lifetime.

Expression of Ki-67 and COX-2 in Patients With Upper Urinary Tract Urothelial Carcinoma

OBJECTIVES To investigate the prognostic value of Ki-67, cyclooxygenase-2 (COX-2), E-cadherin, and retinoblastoma protein (pRB) in patients with urothelial carcinoma of the upper urinary tract. METHODS From January 1998 to December 2005, the specimens from 107 patients with urothelial carcinoma of the upper urinary tract who had undergone nephroureterectomy were analyzed. The expression of Ki-67, COX-2, E-cadherin, and pRB was examined by immunochemistry on tissue microarray sections. The correlation of the immunoreactivity with the pathologic parameters and progression-free and cancer-specific survival were examined. RESULTS Ki-67 and COX-2 were overexpressed in 26 (24%) and 38 patients (36%), respectively. The loss of E-cadherin expression was observed in 66 patients (62%). Altered pRB expression was found in 37 patients (34%). Overexpression of Ki-67 (P = .041 and P = .006, respectively) and COX-2 (P = .002 and P = .001, respectively) was associated with the pathologic stage and grade. Multivariate analysis showed that Ki-67 overexpression (P = .002), T stage (P = .009), and lymph node metastases (P = .009) were independent predictors of progression-free survival. In addition, Ki-67 overexpression (P = .007) and pathologic T stage (P = .003) were independent predictors of cancer-specific survival. No association was found between the pathologic findings and prognosis and the other markers (E-cadherin and pRB). CONCLUSIONS Our results suggest that Ki-67 overexpression is an independent predictor of the progression of urothelial carcinoma of the upper urinary tract. Patients with Ki-67 overexpression should be followed up more closely. In addition, they might be candidates for future prospective therapy trials.

Reduction of Oxidative Stress in Cultured Renal Tubular Cells and Preventive Effects on Renal Stone Formation by the Bioflavonoid Quercetin

PURPOSE We investigated the effects of quercetin on renal tubular cell injury induced by oxalate and the inhibitory effects of quercetin on urinary crystal deposit formation in an animal model. MATERIALS AND METHODS MDCK cells (American Type Culture Collection, Manassas, Virginia) were incubated with different concentrations of oxalate with and without quercetin. MTT (Sigma) assays for cell viability, malondialdehyde and catalase activity were measured to investigate the antioxidant effect of quercetin. Male Sprague-Dawley rats were divided into 3 groups. Group 1 was fed standard rat chow. Groups 2 and 3 rats were fed standard chow supplemented with 3% sodium oxalate for 4 weeks. For the first 8 days in 4 weeks each rat in groups 2 and 3 also received gentamicin intramuscularly. Additionally, group 3 rats were administered quercetin for 4 weeks. Rats were sacrificed after 4 weeks, after which 24-hour urine collections and kidney removal were performed. In the renal tissue malondialdehyde, superoxide dismutase and catalase activity was measured. Bisected kidneys were examined under microscopy to determine the number of crystals. RESULTS The viability of MDCK cells significantly decreased and malondialdehyde production increased in the presence of oxalate. However, co-exposure to quercetin inhibited the decrease in cell viability and inhibited the lipid peroxidation production induced by oxalate. In the animal study malondialdehyde production in group 3 significantly decreased compared to that in group 2. Catalase and superoxide dismutase activity was increased in group 3 compared to that in group 2. The number of crystals in kidneys in group 3 was decreased significantly compared to that in group 2. CONCLUSIONS Quercetin has an inhibitory effect on urinary crystal deposit formation.