Hyun Jin Jung

Initial Experience With Laparoendoscopic Single-site Nephrectomy and Nephroureterectomy in Children

OBJECTIVES To assess the clinical utility and safety of laparoendoscopic single-site surgery (LESS) nephrectomy and nephroureterectomy in children by analyzing 6 consecutive cases performed by a single surgeon. METHODS Since March 2009, we have been performing LESS nephrectomy and nephroureterectomy in children. The indications have been recurrent pyelonephritis related to vesicoureteral reflux with an atrophic kidney and continuous urinary incontinence related to an ectopic ureter. A homemade port was placed through an umbilical incision, and the laparoscopic transperitoneal nephrectomy procedures were performed using various combinations of standard and articulating laparoscopic instruments. The patients undergoing a LESS procedure were evaluated prospectively, and the data were collected during and after surgery. RESULTS A total of 6 procedures, including nephrectomy (4 cases) and nephroureterectomy (2 cases), were completed without intraoperative or postoperative complications. The median operation time was 112 minutes (range 90-148), and the median blood loss was 0 mL (range 0-50). All patients received only oral ibuprofen syrup for pain control and were discharged on postoperative day 2. As the surgeon gained experience, the length of the umbilical incision was decreased from 2.0 to 1.0 cm. CONCLUSIONS Pediatric LESS nephrectomy and nephroureterectomy can be performed safely with a very small incision. LESS performed by an experienced laparoscopic surgeon has the potential to become an alternative first-line therapy for ablative procedures in children.

Renal abscesses measuring 5 cm or less: outcome of medical treatment without therapeutic drainage.

Purpose Diagnosis and proper treatment of renal abscesses remains a challenge for physicians. We investigated the characteristics and comorbidity factors of renal abscesses measuring 5 cm or less and critically examined the effectiveness of conservative treatment. Materials and Methods Between February 2001 and March 2009 the records of 63 patients initially diagnosed at our hospital with renal or perirenal abscesses were retrospectively reviewed. In 63 patients with renal and perirenal abscesses, 51 abscesses measured 5 cm or less, and 49 abscesses were treated with intravenous antibiotics alone. Results Most patients were women (91.8%), and their mean age was 42.3 years. The mean size of renal abscesses was 3.6 cm. The most common predisposing condition was diabetes mellitus (DM) (46.9%). Common clinical features were fever (83.7%) and flank pain (53.1%). On urinalysis, 31 (64.6%) cases had positive bacterial cultures with Escherichia coli (50.0%) being the most common pathogen. All 49 patients were treated with broad-spectrum intravenous antibiotics alone. All patients showed complete clinical regression and resolution of the renal lesions shown by CT between 3 and 14 weeks. The average hospital stay was 15.3 days (range, 5-31 days). Significant predictors of a long hospital stay were age, abscess size, and DM. Conclusion Medium-sized as well as small-sized renal abscesses were treated successfully with intravenous antibiotics alone. DM was a significant predictor of prolonged hospital stay. If therapeutic drainage is believed to involve considerable risk, then intravenous antimicrobial therapy may be a good alternative treatment.

Transvesicoscopic Ureteral Reimplantation in Children with Bilateral Vesicoureteral Reflux: Surgical Technique and Results

OBJECTIVES To report our initial experience with transvesicoscopic cross-trigonal ureteral reimplantation (TVUR), describing stepwise the surgical procedure and determining critical aspects of this surgery in the actual surgical field. SUBJECTS AND METHODS Between September 2008 and April 2010, 48 patients with bilateral vesicoureteral reflux (VUR) underwent TVUR. To identify the critical aspects affecting the surgical difficulty, we divided our TVUR procedure into four steps: TVUR set-up, mobilization of ureters, creation of submucosal tunnels, and ureterovesical anastomosis. To evaluate the evolution of our TVUR, we analyzed changes in the operative time and complications versus increase in surgeon experience (dividing our cases into three groups: the first third, the second third, and the last third). Changes in operative time for all four steps of TVUR were analyzed separately, as well as change in overall operative time. RESULTS Of a total of 48 cases, 45 patients underwent TVUR successfully except for 3 cases of open conversion. Among the 45 cases, the mean overall operative time was 155.6 min. In 1 patient, proximal migration of the ureteral catheter occurred. No other perioperative complications were observed. The mean postoperative hospital stay was 1.6 days. The VUR resolution rate was 96.4%. Upon analysis of our results by step, Step 4 (ureterovesical anastomosis) required the largest portion of the overall operative time in most cases. During the early period of our TVUR, we encountered several technical difficulties. However, the operative times for all four steps were stabilized with increasing number of cases, without deteriorating surgical outcomes. CONCLUSIONS Our report demonstrates that TVUR might potentially be a safe and effective alternative to open ureteral reimplantation in children with VUR, with a shorter learning curve than expected.

Gas chromatography/mass spectrometry based hair steroid profiling may reveal pathogenesis in hair follicles of the scalp

A method of steroid profiling, including androgens, progestins, corticoids and sterols, was developed to evaluate the concentrations of steroids as well as the activities of the enzymes responsible for steroidogenesis in hair by gas chromatography/mass spectrometry. The extraction efficiencies of steroids from the hair matrix were improved by ultrasonication for 1 h at 50 °C. The overall recoveries ranged from 71 to 132%, with a limit of quantification for all analytes ranging from 1 to 50 ng/g. The devised method was used to identify the metabolic changes for both male-pattern baldness (MPB) and the drug efficiency of dutasteride, which inhibits 5α-reductase. Increased dihydrotestosterone levels and the dihydrotestosterone/testosterone (DHT/T) ratio, which is responsible for the 5α-reductase activity, were observed in the MPB patients. A dutasteride treatment resulted in decreases in the DHT and 5α-androstanedione concentrations and DHT/T ratio in the hair samples. Hair steroid profiling reflects the sebaceous status in the scalp and may be useful for monitoring the metabolic responses to both the disease and drug actions.

Function of the Cold Receptor (TRPM8) Associated with Voiding Dysfunction in Bladder Outlet Obstruction in Rats

Purpose Bladder outlet obstruction (BOO) causes storage and voiding dysfunction in the lower urinary tract. We investigated the expression of transient receptor potential cation channel subfamily M member 8 (TRPM8) to evaluate the relationship between TRPM8 expression and overactive bladder (OAB) in a rat model of BOO. Methods Fifty female Sprague-Dawley rats were divided into 4 groups; normal (n=10), normal-menthol (n=10), BOO (n=15), BOO-menthol (n=15). After 3 weeks, cystometry was performed by infusing physiological saline and menthol (3 mM) into the bladder at a slow infusion rate. The histological changes and expression of TRPM8 in the bladder were investigated by Massons trichrome staining, immunofluorescence and reverse transcription-polymerase chain reaction. Results Cystometry showed that the intercontraction interval (ICI; 428.2±23.4 vs. 880.4±51.2, P<0.001), micturition pressure (MP; 25.7±1.01 vs. 71.80±3.01, P<0.001), and threshold pressure (2.9±0.25 vs. 9.2±1.58, P<0.01) were significantly increased in BOO rats. The bladder wall was significantly dilated compared with the control. Detrusor muscle hypertrophy and a thick mucosa layer were observed in BOO bladder. After menthol treatment, ICIs were decreased and MPs were increased in the menthol treatment groups. TRPM8-positive cells and mRNA were predominantly increased in the bladder and dorsal root ganglia of all groups compared with the normal group. Conclusions Increased bladder wall thickness and proportion of collagen probably affect voiding dysfunction. Furthermore, an increase of TRPM8 expression in BOO may induce entry of Ca2+ from the extracellular space or stores. The increase of Ca2+ probably causes contraction of smooth muscle in BOO. However, OAB symptoms were not observed after menthol treatment although the expression of TRPM8 was abundant in the bladder epithelium after menthol treatment. Although OAB in BOO models may be caused by complex pathways, regulation of TRPM8 presents possibilities for OAB treatment.

Database-dependent metabolite profiling focused on steroid and fatty acid derivatives using high-temperature gas chromatography-mass spectrometry.

BACKGROUND A database-dependent gas chromatography-mass spectrometry (GC-MS) based approach was developed for non-targeted metabolite profiling, focusing on 232 steroids, 24 fatty acids, 10 eicosanoids, 10 cannabinoids and 22 steroid-fatty acid esters in biological specimens. METHODS This method, used to search for potent biomarkers in lipid metabolism, included MS based analysis combined with high-temperature gas chromatographic (HTGC) separation of biological metabolites, statistical clustering and an in-house database (DB) searching. RESULTS The HTGC technique showed better detectability of high lipophilic compounds, particularly steroid-fatty acid esters, which generally have poor chromatographic properties on a conventional GC column. The in-house DB search consisted of the retention index and mass spectrum corresponding to each compound selected. The method was applied to tissue samples obtained from cardiac hypertrophy-induced mice. Increased levels of palmitic, linoleic, oleic, and stearic acids and cholesterol were detected and identified. CONCLUSIONS This data-dependent non-targeted metabolite profiling technique could be more effective in biomarker studies associated with the steroid and lipid metabolism than commercially available DBs.

Mass spectrometric profiling of saturated fatty acid esters of steroids separated by high-temperature gas chromatography

An efficient analytical method for simultaneous determination of 12 SFEs in serum is described. The method involves solid-phase extraction to isolate of SFEs from interfering species, especially cholesteryl esters, conversion to trimethylsilyl (TMS) ether derivatives for the direct analysis by gas chromatography-mass spectrometry (GC-MS) using a high temperature MXT-1 (Silcosteel-treated stainless steel) capillary column. All SFEs as their TMS derivatives were well separated with excellent peak shapes within 12 min. Overall recoveries ranged from 88% to 119%, with a detection limits for SFEs ranged from 2 to 30 microg L(-1). The linearity as correlation coefficient was higher than 0.99 except for pregnenolone-3-arachidate (r(2)=0.98) in the concentration range of 5-3000 microg L(-1). Ten serum samples obtained from volunteers were also analyzed and quantitatively determined of DHEA-3-palmitate and pregnenolone-3-stearate in 1.8-1195.8 microg L(-1) concentration. The devised high temperature GC-MS method could be useful for identification of SFEs in biological specimens including serum.

Single-surgeon Experience With Transvesicoscopic Ureteral Reimplantation in Children With Vesicoureteral Reflux

OBJECTIVES To review our initial experience with transvesicoscopic ureteral reimplantation (TVUR) in children with vesicoureteral reflux and to evaluate the learning curve for the feasibility and reproducibility of TVUR. METHODS TVUR was performed in 28 consecutive patients with a mean age of 6.0 years. Cohens classic technique was reproduced using a laparoscopic technique with two 3-mm working ports and a 5-mm camera port. RESULTS TVUR was successfully completed in 26 patients. In 2 patients, TVUR was converted to open intravesical reimplantation. The postoperative vesicoureteral reflux resolution rate was 94.6% (35 of 37 ureters). The mean operative time for TVUR was 166 minutes for unilateral reimplantation and 189 minutes for bilateral reimplantation. When the operation times of the first 13 and the last 13 patients were compared, the mean operative time had decreased significantly for the last 13 patients compared to that for the first 13 patients (140 vs 220 minutes). The mean postoperative hospital stay was also significantly shorter for the last 13 patients than for the first 13 patients (1.08 vs 1.69 days). CONCLUSIONS TVUR is currently performed at only at a few centers because of the technical difficulties and the potentially steep learning curve. However, our results have indicated rapid improvement in the operative time within a short period, suggesting a shorter learning curve for TVUR than expected. TVUR is a reproducible procedure and is a reasonable option for the treatment of vesicoureteral reflux.

Factors Associated with Complications of the Ureteral Stump After Proximal Ureteroureterostomy

PURPOSE Ureteroureterostomy is a treatment modality for managing an ectopic ureterocele or ectopic ureter and preserving upper pole kidney function. However, the development of urinary tract infection at the residual ureteral stump is a concern. We analyzed factors affecting the development of urinary tract infection at the residual ureteral stump after proximal ureteroureterostomy. MATERIALS AND METHODS Between January 2002 and December 2009 proximal ureteroureterostomy was performed in 80 patients with ectopic ureterocele or ectopic ureter associated with a duplex system. Excluding 6 patients who did not meet the study inclusion criteria, we investigated age at operation, diameter of the upper pole ureter on ultrasonography, differential renal function and the presence of vesicoureteral reflux in 74 patients. Risk factors for residual ureteral stump infection and decreased differential renal function were analyzed. RESULTS During a median followup of 5.0 years an additional operation was required in 9 patients (12.2%) due to urinary tract infection at the residual ureteral stump a median of 2.4 years after initial proximal ureteroureterostomy. The preoperative maximal diameter of the upper pole ureter was significantly greater in patients with infection complications. The postoperative maximal diameter of the upper pole ureter was also significantly greater on postoperative ultrasonography performed a median 43.0 days after the operation. Median preoperative and postoperative differential renal function was 47.8% and 47.0%, respectively. No preoperative factors were significantly related to the decrease in differential renal function. CONCLUSIONS Proximal ureteroureterostomy is a safe treatment for ectopic ureterocele or ectopic ureter with a low postoperative complication rate. Upper pole ureter diameter was correlated with the development of a urinary tract infection at the residual ureteral stump.

Clinical course of vesicoureteral reflux in patients with hypospadias

Objectives:  The prevalence of vesicoureteral reflux (VUR) in hypospadic patients is reportedly higher than in healthy children. We investigated the prevalence and the clinical course of VUR in hypospadic patients.