Management of urinary tract infection in patients with spinal cord injuries

Urinary tract infection (UTI) is responsible for major morbidity and mortality in spinal cord injury (SCI) patients. Several factors appear to be responsible for an increased risk of infection in the neurogenic bladder. Incomplete voiding, elevated intravesical pressure and catheter use contribute to an increased risk of symptomatic urinary tract infection. Frequent exposure to antibiotics increases the risk of infection by resistant organisms. UTIs interfere with rehabilitation, and may lead to secondary urologic complications. The classic symptoms of UTI are unreliable indicators in SCI patients with neurogenic bladder. Lack of pyuria reasonably predicts the absence of UTI in SCI patients. Asymptomatic bacteriuria need not be treated with antibiotics. Symptomatic UTI warrants therapy in all patients.     

Renal excretory sectors

One thousand and ninety-four normal human kidneys and 18 abnormal (with duplication of the ureter) were studied by the corrosion method and pyelography followed by topometric and mathematics analyses. It was found that the renal pelvis is a calicopelvic complex built up of renal calices, urine ducts and renal pelvis. Before opening into the renal pelvis, renal calices join together forming urine ducts (superior and inferior; or superior, middle and inferior; or superior, middle anterior, middle posterior and inferior) which transport urine to the container, the renal pelvis. It can be seen that groups of renal calices with pyramids and their surrounding cortical substance form the renal excretory sectors of the kidneys where the processes of uropoiesis and transportation of urine through elements of the nephron and calicopelvic complex take place. These are two (superior and inferior), three (superior, middle and inferior) or four (superior, middle anterior, middle posterior and inferior) renal excretory sectors. The existence of renal excretory sectors is proved by congenital anomalies of the calicopelvic complex such as duplication of the ureter, where urine ducts of the superior and inferior renal excretory sectors do not form a renal pelvis but run separately to the urinary bladder. On the basis of anatomical data obtained, renal excretory sectors may be distinguished, analogous to bronchopulmonary segments in lungs. These data about renal excretory sectors will contribute to further improvement in the operative technique of renal partial resections as well as to anatomical nomenclature.     

Flow dynamics in a stented ureter

Sarah Waters Oxford Centre for Industrial and Applied Mathematics, Mathematical Institute, 24–29 St Giles’, Oxford OX1 3LB, UK Jonathan Wattis and Linda Cummings Department of Mathematical Science, New Jersey Institute of Technology, Newark, NJ 07102, USA Email: j.siggers{at}imperial.ac.uk Received on July 19, 2007. Revised on August 23, 2008. Accepted on August 28, 2008. Vesicorenal reflux is a major side effect associated with uretericstent placement. In a stented upper urinary tract when the bladderpressure rises, such as during bladder spasms (due to irritationcaused by the stent) or voiding of the bladder, it drives urinereflux up the ureter, which, in turn, may be a contributoryfactor for infections in the renal pelvis. We develop a mathematicalmodel to examine urine flow in a stented ureter, assuming thatit remains axisymmetric and treating the wall as a non-linearelastic membrane. The stent is modelled as a rigid, permeable,hollow, circular cylinder lying coaxially inside the ureter.The renal pelvis is treated as an elastic bag, whose volumeincreases in response to an increased internal pressure. Fluidenters the renal pelvis from the kidney with a prescribed flux.The stent, ureter and renal pelvis are filled with urine, andthe bladder pressure is prescribed. We use the model to calculatethe total volume of reflux generated during rises in bladderpressure and investigate how it is affected by the stent andureter properties.     

Transmural Pressure of the Urinary Bladder Wall

Intragastric, perivesical and intravesical pressures were registered during slow filling of the urinary bladder in nine healthy men in the supine and sitting positions. Intragastric pressure was fairly constant in both positions, but intravesical pressure rose and there was also a slight rise of perivesical pressure. In both body positions transmural pressure, i.e. the pressure difference between the inside and the outside of the tbladder, rose during bladder filling. In both body positions at bladder volumes ^ 300 ml, in this material, transmural pressure, determined as the difference between intravesical and perivesical pressures, did not differ statistically significantly from transmural pressure calculated as the difference of intravesical and intragastric pressures minus a hydrostatic component. At maximal bladder volumes transmural pressure determined in the first way was statistically significantly lower than that calculated in the second way. In the supine position the transmural pressure at bladder volume 300 ml, calculated as the difference of intravesical and perivesical pressures, was lower than in the upright position.     

Pathophysiological aspects of bladder dysfunction: a new hypothesis for the prevention of 'prostatic' symptoms

This article reviews the literature on the pathophysiology of male lower urinary tract symptoms (LUTS) with the intention of developing a new preventive intervention for this bothersome disease. Traditionally, male voiding dysfunction has been thought to arise from bladder outlet obstruction (BOO) caused by prostatic enlargement. Many years of research, however, have shown that a clear relationship between the size of the prostate and the occurrence or severity of symptoms is doubtful. Because of its crucial role in urination, it is increasingly being accepted that the clinical manifestation of voiding dysfunction relies on the functional behaviour of the bladder. Several animal studies have shown that bladder performance can be improved by increasing urine output. Contrary to alterations observed in pathologic situations, an increased urine output provides a physiologic stimulus for animal bladder function improvement. We hypothesise that a trained bladder should be less susceptible to the harmful effects of ageing and obstruction. Future symptoms may thus be prevented. In humans an increased urine output can be achieved by drinking additional water, which could be an adequate preventive intervention.     

Role of protein kinase C in central muscarinic inhibitory mechanisms regulating voiding in rats

To evaluate the role of protein kinase C in central muscarinic mechanisms regulating voiding, cystometry was performed in conscious rats. Oxotremorine methiodide, a muscarinic agonist was injected i.c.v. in a dose (0.1 microg/rat) shown previously to alter voiding function. Oxotremorine methiodide was also tested after i.c.v. injection of chelerythrine chloride (a protein kinase C inhibitor, 2 microg/rat) or 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H-7, a protein kinase inhibitor, 5 nmol/rat). In untreated rats, oxotremorine methiodide elicited a bimodal response consisting of an initial increase in bladder capacity, maximal voiding pressure, pressure threshold and post voiding intravesical pressure, but reduced voiding efficiency and bladder compliance. The second response consisted of a decrease in bladder capacity and bladder compliance, increases in maximal voiding pressure and post voiding intravesical pressure, but no change in pressure threshold or voiding efficiency. However, approximately 20 min after pre-treatment with chelerythrine chloride or H-7 in doses that did not alter voiding function, oxotremorine methiodide decreased bladder capacity, increased maximal voiding pressure, but did not change pressure threshold or voiding efficiency. These results indicate that inhibitory and facilitatory muscarinic mechanisms in the brain that control voiding function involve different second messenger systems. Inhibitory mechanisms which are blocked by chelerythrine chloride or H-7 must involve protein kinase C and normally be inactive because the protein kinase inhibitors alone did not alter voiding. On the other hand, facilitatory muscarinic mechanisms which previous studies showed were tonically active are not mediated by chelerythrine chloride or H-7 sensitive signaling pathways.     

Relationship between Perivesical and Intravesical Urinary Bladder Pressures and Intragastric Pressure

The intragastric pressure and the perivesical and intravesical urinary bladder pressures were measured in the supine and sitting positions immediately after micturition in 9 healthy men. The intragastric pressure was measured with an air-filled rubber balloon, the perivesical pressure with an open liquid-filled catheter inserted above the pubic bone into the space of Rezius and the intravesical pressure of the almost empty bladder with a catheter inserted supra-pubically. There was no difference between the intragastric pressure level and the peri- and intravesical pressure levels in the supine position, but in the sitting position the peri- and intravesical pressure levels were higher than the intragastric pressure levels due to the pressure effect of the viscera. There was no difference between perivesical and intravesical pressure levels in either the supine or sitting position. Rapid pressure change produced by straining or coughing produced a smaller pressure increase peri- and intravesically than intragastrically due to delayed pressure equilibration because of inhomogeneity of the abdominal contents.     

Assessment of Intramural Blood Flow and Neurogenic Control in Intact and Hypertrophic Urinary Bladder with Harmonic Analysis of Bioimpedance in Rats

High-resolution impedancometry and harmonic (Fourier) analysis of variable component of bioimpedance revealed rhythmic oscillations of urinary bladder bioimpedance at the Mayer wave, respiration, and heartbeat frequencies. The power values of the corresponding Mayer, respiratory, and cardiac peaks were calculated to assess circulation in the urinary bladder wall and its autonomic nervous control at various stages of infusion cystometry in intact rats and in the rats with preliminary formed infravesical obstruction (IVO). In intact rats, filling of the bladder with physiological saline diminished the power of the first (fundamental) cardiac peak attesting to a decrease of the blood flow in the bladder wall. Simultaneously, the power of low-frequency Mayer peak reflecting sympathetic activity increased, while the power of respiratory peak decreased supposedly reflecting abatement of the parasympathetic influences. Bladder voiding was accompanied by a decrease of Mayer peak and increase of the respiratory one. Prior to infusion cystometry, the intravesical pressure in IVO rats was elevated while the power of fundamental cardiac peak was below the control value. Filling the bladder in these rats was accompanied by further decrease of the cardiac peak reflecting still greater drop in blood supply. In control rats, voiding the bladder normalized the vesical circulation assessed by the cardiac peak, while in IVO rats this peak remained decreased. The reciprocal changes of Mayer and respiratory peaks observed during infusion cystometry in the norm were replaced by unidirectional decrease in the power of both peaks in IVO rats, which probably attest to disturbance of autonomic nervous control in the hypertrophic urinary bladder in these rats.     

Villous adenoma of urinary tract: a common tumor in an uncommon location

The presence of colonic-type epithelium in the urinary tract is not an uncommon occurrence, but tumors derived from it are rare. Tumors arising from colonic-type epithelium, including villous adenoma and adenocarcinoma, have been reported in the renal pelvis, ureter, urinary bladder, and urethra. Villous adenomas of the urinary tract are rare, being most common in the urinary bladder, followed by the urethra. Morphologic features of these tumors are similar to those of the colonic adenomas. The largest published series of villous adenomas of the urinary tract was a study of 23 patients. This study is reviewed and other reports on villous adenomas of the urinary tract are discussed.     

Smooth muscle hypertrophy following partial bladder outlet obstruction is associated with overexpression of non-muscle caldesmon

Partial bladder outlet obstruction (PBOO) induces remodeling of urinary bladder smooth muscle (detrusor). We demonstrate an increase in bladder wall mass, muscle bundle size, and a threefold increase in the cross-sectional area of detrusor myocytes following PBOO in male New Zealand White rabbits compared to that of controls. Some bladders with detrusor hypertrophy function close to normal (compensated), whereas others were dysfunctional (decompensated), showing high intravesical pressure, large residual urine volume, and voiding difficulty. We analyzed the expression of smooth muscle-specific caldesmon (h-CaD) and non-muscle (l-CaD) by Western blotting, RT-PCR, and real-time PCR. The expression of l-CaD is increased significantly at the mRNA and protein levels in the decompensated bladders compared to that of normal and compensated bladders. The CaD was also co-localized with myosin containing cytoplasmic fibrils in cells dissociated from obstructed bladders and cultured overnight. Our data show that the inability of decompensated bladders to empty, despite detrusor hypertrophy, is associated with an overexpression of l-CaD. The level of l-CaD overexpression might be a useful marker to estimate the degree of detrusor remodeling and contractile dysfunction in PBOO.     

Prune-belly syndrome with prostatic hypoplasia, bladder wall rupture, and massive ascites in a fetus with trisomy 18

An association has been noted between trisomy 18 and genitourinary abnormalities, with six previous reports of the prune-belly syndrome occurring in patients with trisomy 18. We have observed a 120-g fetus of 18 weeks' gestational age at autopsy in whom there was severe prune-belly syndrome and trisomy 18. Serial histologic sections and reconstruction of the lower urinary tract demonstrated severe prostatic hypoplasia with a dilated, angulated prostatic urethra. Obstruction appeared to be present at the internal sphincter as a result of loss of prostatic support of the bladder. The bladder was distended and hypertrophic, and had a disruption of its wall near the apex. Massive ascites and intraabdominal urine accumulation had produced abdominal distention and pulmonary hypoplasia. The findings in this case lend support to the concept of prostatic hypoplasia as a cause of prune-belly syndrome and to the unexplained association between trisomy 18 and genitourinary anomalies including the prune-belly syndrome.     

Anatomical tracer injections into the lower urinary tract may compromise cystometry and external urethral sphincter electromyography in female rats

Physiological and anatomical investigations are commonly combined in experimental models. When studying the lower urinary tract (LUT), it is often of interest to perform both urodynamic studies and retrogradely labeled neurons innervating the peripheral target organs. However, it is not known whether the use of anatomical tracers for the labeling of, e.g. spinal cord neurons may interfere with the interpretation of the physiological studies on micturition reflexes. We performed cystometry and external urethral sphincter (EUS) electromyography (EMG) under urethane anesthesia in adult female rats at 5–7 days after injection of a 5% fluorogold (FG) solution or vehicle into the major pelvic ganglia (MPG) or the EUS. FG and vehicle injections into the MPG and EUS resulted in decreased voiding efficiency. MPG injections increased the duration of both bladder contractions and the inter-contractile intervals. EUS injections decreased EUS EMG bursting activity during voiding as well as increased both the duration of bladder contractions and the maximum intravesical pressure. In addition, the bladder weight and size were increased after either MPG or EUS injections in both the FG and vehicle groups. We conclude that the injection of anatomical tracers into the MPG and EUS may compromise the interpretation of subsequent urodynamic studies and suggest investigators to consider experimental designs, which allow for physiological assessments to precede the administration of anatomical tracers into the LUT.     

Anomalies of the kidney and urinary tract are common in de Lange syndrome

Sixty-one patients affected by de Lange syndrome underwent a careful renal and urological evaluation including family and personal history, physical examination, urinalysis, renal tract ultrasonography, and serum creatinine. A voiding cystourethrography was performed in patients with urinary tract infections, in patients with renal ectopy, and in patients with small kidneys. Structural anomalies of the kidney and urinary tract were detected either by ultrasound or voiding cystourethrography in 25 patients (41%): absent or poor corticomedullary differentiation (N = 8; 13%), pelvic dilation (N = 6; 10%), vesicoureteral reflux (N = 5; 8%), small kidney (N = 3; 5%), isolated renal cyst (N = 3; 5%), and renal ectopia (N = 2; 3%). Renal function was normal in 52 patients (85%) but reduced in 9 patients (15%) with renal tract abnormalities. Overt proteinuria was disclosed in three patients with impaired renal function.     

Importance of accurate diagnosis in counseling for neural tube defects diagnosed prenatally

In cases of fetal neural tube defects (NTD), termination of pregnancy without ascertainment of specific etiology may lead to provision of incorrect recurrence risks and erroneous diagnosis in future pregnancies. Four patients are presented who illustrate the etiologic diversity of neural tube defects. The patients were referred for prenatal diagnosis because of elevated maternal serum alphafetoprotein (AFP). All four chose pregnancy termination. Diagnostic methods included fetal ultrasound, amniocentesis for fetal karyotyping and amniotic fluid AFP/acetylcholinesterase (AChE) and/or fetal karyotyping after delivery, and dysmorphology evaluation of the fetus after intact delivery. These cases highlight the benefits of fetal karyotype analysis and of an intact delivery and thorough clinical examination of the fetus when patients choose to terminate pregnancies with fetal anomalies.     

Neural mechanisms of impaired micturition reflex in rats with acute partial bladder outlet obstruction

To determine the contribution of neural elements to micturition, we evaluated, in intact rats, the cystometrogram, pelvic afferent nervous activity, pelvic efferent nervous activity and external urethral sphincter-electromyogram activity in the normal and acute partial bladder outlet obstruction states. In the normal state, in response to saline filling, mechanoreceptor-dependent pelvic afferent nervous activity gradually activated and finally triggered a voiding reflex, including four phases of detrusor contractions. Phase 1 was characterized by an initial rising intravesical pressure, Phase 2 was characterized by a series of high-frequency oscillations in intravesical pressure, Phase 3 contraction was characterized by a rebound intravesical pressure and Phase 4 contraction was characterized by a rapid fall in intravesical pressure. In the acute partial bladder outlet obstruction state, Phase 1 contraction rose and high-frequency oscillations fell in Phase 2. This voiding dysfunction is ascribed to the bursting extraurethral sphincter activity being converted to tonic extraurethral sphincter activity. In summary, the suppressed high-frequency oscillations in Phase 2 of the detrusor muscle contraction could be detrimental to efficient voidings in the acute partial bladder outlet obstructed rat.     

输尿管支架细菌生物膜观察及病原菌分布和耐药性

文题释义：细菌生物膜：细菌及其细胞外产物在载体表面聚集形成的一种有序群落，其主要成分为多糖蛋白复合物，是多种细菌相互粘连而产生得具有特定结构的细菌复合体。细菌生物膜分3层：连接膜附着于组织或生物材料表面；基底膜包含致密的菌群；表面膜为最外层，浮游菌可从其表面被释放后自由飘浮和播散。微菌落是生物膜的基本结构单位，微菌落相互融合连接形成大片均一的生物膜。  导管相关性尿路感染：导尿管相关尿路感染主要是指患者留置导尿管后或者拔除导尿管48 h内发生的泌尿系统感染。 背景：输尿管支架被广泛用于肾盂输尿管交界处狭窄、原位尿流改道重建、输尿管或肾镜碎石、肾移植和肿瘤等泌尿系疾病，但长期留置输尿管支架可导致导管相关性尿路感染等并发症。 目的：观察输尿管支架表面细菌生物膜的形态学特点，分析细菌生物膜的病原学分布特征及耐药性。 方法：收集2016年1至12月重庆医科大学附属永川医院127例患者的输尿管支架标本，扫描电镜观察支架表面细菌生物膜的形态学特征，刚果红培养基分别筛选肾盂段、输尿管段和膀胱段支架的细菌生物膜菌株，同时进行尿培养，对检出的病原菌进行药敏试验分析。实验获得重庆医科大学附属永川医院伦理委员会批准，批准号：2014年科伦审22号。 结果与结论：①在留置7，15，30 d的输尿管支架表面均能够观察到细菌生物膜及数量不等的炎性附着物或结晶体，细菌生物膜的细菌被大量纤维膜包裹；留置7，15 d的输尿管支架表面可见呈片状散在分布的菌落，以杆菌为主；留置30 d的输尿管支架表面可见呈堆状分布的菌落，以球菌、杆菌为主；②127份输尿管支架标本中检出细菌生物膜106份，阳性率为83.5%，其中膀胱段阳性率最高，其次为肾盂段和输尿管段；尿培养阳性为25份，阳性率为19.7%，尿液培养的细菌生物膜阳性率明显低于输尿管支架培养结果(P < 0.05)；③106份阳性标本中检出细菌227株，其中革兰阴性菌株数显著高于革兰阳性菌株数(P < 0.05)；输尿管支架细菌生物膜和尿培养细菌均主要以大肠杆菌、铜绿假单胞菌、粪肠球菌和屎肠球菌最为常见；④输尿管支架管表面细菌生物膜菌株的耐药率高；⑤结果表明输尿管支架细菌生物膜是诱发导管相关性尿路感染的重要因素。 ORCID: 0000-0001-9204-7321(张家模) 中国组织工程研究杂志出版内容重点：生物材料；骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性；组织工程     

Intermittent self catheterization for patients with urinary incontinence or difficulty emptying the bladder.

Urinary incontinence, difficulty voiding and recurrent urinary tract infections are common in general practice. In patients with multiple sclerosis, spina bifida, intervertebral disc lesions, spinal injuries or tumours, the symptoms may be associated with a high residual volume of urine owing to a neuropathic bladder. Similar complaints may occur in elderly people or in women with gynaecological problems owing to atonic urinary retention. Provided that a significant residual volume of urine is found on abdominal examination, ultrasound, x-ray or catheterization, both groups of patients may be helped by intermittent self catheterization. Intermittent self catheterization is a safe and simple technique. By catheterizing themselves between four and six times daily patients can gain control over their bladders. Abandoning indwelling catheters or bulky external appliances does much for a patient's morale and self esteem. In addition, since the bladder is being drained effectively, urinary tract infections cease to be a problem and the kidneys are safeguarded. Severe disability is not a contraindication since patients in wheelchairs have mastered the technique despite paraplegia, an anaesthetic perineum, spinal deformity, intention tremor, mental handicap, old age or blindness. Patients should be referred to urologists for a trial of intermittent self catheterization. If unsuccessful or unacceptable it can be abandoned with no long term consequences. If it is effective the benefits may be considerable.     

Nested variant of urothelial carcinoma of the renal pelvis

The nested variant of urothelial carcinoma is an uncommon form of urothelial carcinoma with distinctive histopathologic features. The majority of cases of this unusual type of urothelial carcinoma have been described in the urinary bladder, with examples of this neoplasm involving the upper urinary tract being extremely limited. The present report details the clinical and pathologic features of an unusual case of a nested variant of urothelial carcinoma occurring in the renal pelvis of a 71-year-old woman. The tumor was characterized by a nested pattern of growth and relatively bland cytologic features, and presented with locally advanced disease at the time of nephroureterectomy. Although rare, awareness that the nested variant of urothelial carcinoma may occur at this particular site is important so as not to confuse this unusual form of urothelial carcinoma with other pathologic lesions of the renal pelvis.