Hardeep Phull

Multiplex pathogen identification for polymicrobial urinary tract infections using biosensor technology: a prospective clinical study.

PURPOSE Rapid diagnosis of urinary tract infection would have a significant beneficial impact on clinical management, particularly in patients with structural or functional urinary tract abnormalities who are highly susceptible to recurrent polymicrobial infections. We examined the analytical validity of an electrochemical biosensor array for rapid molecular diagnosis of urinary tract infection in a prospective clinical study in patients with neurogenic bladder. MATERIALS AND METHODS The electrochemical biosensor array was functionalized with DNA probes against 16S rRNA of the most common uropathogens. Spinal cord injured patients at a Veterans Affairs hospital were recruited into the study. Urine samples were generally tested on the biosensor within 1 to 2 hours of collection. Biosensor results were compared with those obtained using standard clinical microbiology laboratory methods. RESULTS We successfully developed a 1-hour biosensor assay for multiplex identification of pathogens. From July 2007 to December 2008 we recruited 116 patients, yielding a total of 109 urine samples suitable for analysis and comparison between biosensor assay and standard urine culture. Of the samples 74% were positive, of which 42% were polymicrobial. We identified 20 organisms, of which Escherichia coli, Pseudomonas aeruginosa and Enterococcus species were the most common. Biosensor assay specificity and positive predictive value were 100%. Pathogen detection sensitivity was 89%, yielding a 76% negative predictive value. CONCLUSIONS To our knowledge we report the first prospective clinical study to successfully identify pathogens within a point of care time frame using an electrochemical biosensor platform. Additional efforts to improve the limit of detection and probe design are needed to further enhance assay sensitivity.

Severe disease on endoscopy and steroid use increase the risk for bowel perforation during colonoscopy in inflammatory bowel disease patients.

BACKGROUND AND AIM Colonoscopic perforation is a rare complication. We sought to determine its risk factors in patients with inflammatory bowel disease (IBD). MATERIALS AND METHODS The study group consisted of 19 IBD patients who had perforation secondary to diagnostic or therapeutic colonoscopy from January 2002 to October 2010. The control group consists of 76 IBD patients undergoing colonoscopy and no perforations that were matched based on indication in a 4:1 ratio to the study group. Demographic and clinical variables as well as perforation outcomes were analyzed by univariate and multivariate analyses. RESULTS There were a total of 5295 colonoscopies done during the study period in IBD patients of which 19 patients had perforation. The prevalence of perforation in IBD patients was 0.3%. Of the 19 patients, 12 had Crohns disease (CD) and 7 had ulcerative colitis (UC). Patients in the perforation group were more likely treated with steroids (68.4% vs. 21.1%, p<0.001) and had severe disease on endoscopy (31.6% vs. 10.1%, p=0.03) than that in the control groups. On multivariate analysis, severe disease on endoscopy (adjusted odds ratio [aOR]=3.82, 95% confidence interval [CI]=1.03-15.24) and steroid treatment (aOR=7.68; 95% CI=1.48, 39.81) were independently associated with the risk of perforation. The median length of stay in the perforation group was 10 days (range 2-23 days). There was no mortality in our study. CONCLUSIONS There appears to be a higher risk of colonoscopy-associated perforation in IBD patients with active disease and on steroids.

The effect of sildenafil citrate on bladder outlet obstruction: a mouse model

To investigate if sildenafil citrate can inhibit the functional and structural changes of the detrusor in a murine model of bladder outlet obstruction (BOO). Phosphodiesterase type 5 (PDE‐5) inhibitors have recently been used for treating urinary symptoms associated with prostatic obstruction, but it is unclear whether PDE‐5 inhibition acts on the prostatic urethra or the bladder.

Angiotensin II plays a role in acute murine experimental autoimmune cystitis

To investigate whether angiotensin II (AII) receptor antagonism decreases the inflammation and oedema in acute murine experimental autoimmune cystitis (EAC), as interstitial cystitis (IC) might have an autoimmune component and AII has been implicated in autoimmune‐mediated vascular congestion, oedema and scarring.

Chronic sacral nerve stimulation prevents detrusor structural and functional changes associated with bladder outlet obstruction--a rat model.

Bladder outlet obstruction (BOO) can mediate structural and functional detrusor changes, which can lead to bothersome lower urinary tract symptoms. We investigate if sacral nerve stimulation (SNS) can prevent these structural and functional changes in a rat model of BOO.

Angiotensin II type 1 (AT-1) receptor inhibition partially prevents the urodynamic and detrusor changes associated with bladder outlet obstruction: a mouse model.

Study Type – Therapy (case control)

Vulnerability of continence structures to injury by simulated childbirth

The goal of this study was to examine acute morphological changes, edema, muscle damage, inflammation, and hypoxia in urethral and vaginal tissues with increasing duration of vaginal distension (VD) in a rat model. Twenty-nine virgin Sprague-Dawley rats underwent VD under anesthesia with the use of a modified Foley catheter inserted into the vagina and filled with saline for 0, 1, 4, or 6 h. Control animals were anesthetized for 4 h without catheter placement. Urogenital organs were harvested after intracardiac perfusion of fixative. Tissues were embedded, sectioned, and stained with Massons trichrome or hematoxylin and eosin stains. Regions of hypoxia were measured by hypoxyprobe-1 immunohistochemistry. Within 1 h of VD, the urethra became vertically elongated and displaced anteriorly. Edema was most prominent in the external urethral sphincter (EUS) and urethral/vaginal septum within 4 h of VD, while muscle disruption and fragmentation of the EUS occurred after 6 h. Inflammatory damage was characterized by the presence of polymorphonuclear leukocytes in vessels and tissues after 4 h of VD, with the greatest degree of infiltration occurring in the EUS. Hypoxia localized mostly to the vaginal lamina propria, urethral smooth muscle, and EUS within 4 h of VD. Increasing duration of VD caused progressively greater tissue edema, muscle damage, and morphological changes in the urethra and vagina. The EUS underwent the greatest insult, demonstrating its vulnerability to childbirth injury.

Delivery of Intercellular Adhesion Molecule-1 Antisense Oligonucleotides Using a Topical Hydrogel Tissue Sealant in a Murine Partial Nephrectomy/Ischemia Model

OBJECTIVES Ischemia/reperfusion injury is a leading cause of renal damage which can be improved with antisense oligonucleotide gene therapy. We have shown that polyethylene glycol (PEG) hydrogel, which also functions as a tissue sealant, is an effective topical delivery vehicle for oligonucleotides in a murine partial nephrectomy model. The objective of this study was to use and evaluate this method against intercellular adhesion molecule-1 (ICAM-1) to prevent tissue damage. METHODS Sixty mice underwent left upper pole partial nephrectomy with 45 minutes of warm ischemia, randomized to treatment with 50 microg ICAM-1 antisense oligonucleotides embedded in PEG hydrogel, no therapy, or sham surgery. Kidneys were harvested at 24 hours and 3, 4, and 5 days. The specimens were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) for ICAM-1 messenger ribonucleic acid (mRNA), immunohistochemical staining for ICAM-1 protein, and standard histology. RESULTS At 24 hours, qRT-PCR and immunohistochemistry data showed a significant reduction in ICAM-1 mRNA and protein expression in the antisense group versus the ischemia group, but no difference at 3 to 5 days. Histologically there was reduced inflammation and necrosis in the cortex at 24 hours. The outer and inner medulla also showed improvement at 3 to 5 days in the antisense group as opposed to the ischemia group. CONCLUSIONS Topical PEG hydrogel delivery of antisense ICAM-1 oligonucleotides demonstrated decreased ICAM-1 mRNA expression, reduced ICAM-1 protein staining, and decreased cellular damage. The application of gene therapy through this novel topical delivery system holds potential for a highly specific, localized method of preventing tissue damage after ischemia/reperfusion injury.

ROLE OF URODYNAMICS ON CLINICAL DECISION-MAKING IN PATIENTS WITH URINARY INCONTINENCE AND VOIDING DYSFUNCTION

analysis, we used the prolapse (POPDI) and urinary (UDI) subscales of the PFDI. We used Wilcoxon ranked test and McNemar test for repeated parametric and categorical variables, respectively. RESULTS: Thirty-three women with a mean age of 79 years (65-90) were included in the analysis. The median follow-up was 9 months (3-23 months). Prior to surgery, the median POP-Q stage was 3 (range 2-4). Nearly all (91%) had some incontinence symptoms, and 80% reported symptoms of stress urinary incontinence (SUI). Preoperative urodynamic diagnoses included: urodynamic stress incontinence (USI)

A COMPARISON OF URINARY FUNCTIONAL OUTCOMES IN ADULT HYPOSPADIACS WITH AND WITHOUT ONGOING PROBLEMS IN ADULTHOOD

RESULTS: Thirty-four hypospadias patients (77.2%) and 13 controls (65%) completed the questionnaire. The hypospadias patients were divided into 2 groups based on the preoperative position of the meatus: proximal (P) (n = 24) and distal (D) (n = 9). One patient could not be classified into any of the groups. The mean age of the patients at the time of the initial operation was 3.3 years (range: 1-10 years) and the mean duration after the initial operation was 11.3 years (range: 4-27 years). The mean current age of both the patients and controls was 14.6 years. All subjects could void in the standing position: 8.3% patients in group P, 11.1% in group D, and 7.6% of the controls reported spraying of the urinary stream. Two patients in group P (8.3%) were dissatisfied with the appearance of their penis, and 8.7% in group P, 22.2% in group D, and 8.3% of the controls were disappointed with the size of their penis. The percentages of subjects who expressed interest in watching adult videos were 53.8% in group P, 50.0% in group D, and 100% of the controls (over 13 years old). None of the patients complained of penile pain during erection. CONCLUSIONS: We found that the repair of severe hypospadias could result in different problems and dissatisfaction, particularly regarding penile size and erection, therefore, we concluded that patients undergoing hypospadias repair require long-term follow-up and adequate counseling for future voiding and sexual dysfunction.