Bladder stone incidence in persons with spinal cord injury: determinants and trends, 1973-1996

Bladder Management Strategies for Urological Complications in Patients with Chronic Spinal Cord Injury

Neurogenic lower urinary tract dysfunction, common in patients with chronic spinal cord injury, inevitably results in urological complications. To address neurogenic lower urinary tract dysfunction after spinal cord injury, proper and adequate bladder management is important in spinal cord injury rehabilitation, with the goal and priorities of the protection of upper urinary tract function, maintaining continence, preserving lower urinary tract function, improvement of SCI patients' quality of life, achieving compatibility with patients' lifestyles, and decreasing urological complications. This concise review aims to help urologists address neurogenic lower urinary tract dysfunction by focusing on the risks of long-term urological complications and the effects of different bladder management strategies on these complications based on scientifically supported knowledge.

What do X-ray images of the bladder during video urodynamics show us in patients with spinal cord injury?

STUDY DESIGN

Retrospective anonymized cohort study.

OBJECTIVES

To study X-ray images of video urodynamics (VUD) in patients with spinal cord injury (SCI).

SETTING

Single-center study.

METHODS

X-ray images during VUD were categorized. Relation with the American Spinal Injury Association Impairment Scale (AIS), time since and level of SCI, cystometric data, method of bladder management, findings of flexible cystoscopy, and renal ultrasound were evaluated. Changes over time were studied.

RESULTS

In 231 consecutive patients, VUD was done at a mean of 8.5 years after SCI. X3-ray bladder appearance was categorized as normal/standard, tonic, or flaccid. In 19 patients, specific findings were seen: diverticula, cystocele, vesicoureteral reflux. X-ray images differed by maximum cystometric capacity, presence of neurogenic detrusor overactivity, and maximum detrusor pressure during detrusor overactivity, but not by bladder compliance. There was no difference in the categories found in different levels and completeness of SCI. In the 23 patients able to void no pathology was seen on urethral images. Renal ultrasound was normal in >99%. In 86 patients, repeated testing after 72 ± 143 weeks showed changed findings in 30%. Cystoscopy showed significantly more local pathologies.

CONCLUSION

Complications in the lower urinary tract were seen on imaging only in a limited number of our cohort. As our findings represent a real-life example of the actual yield of VUD in patients with neurogenic bladder due to SCI treated following the international guidelines, further multicentre evaluation is needed to determine when imaging should be used or not.

Case report. Geschokt door de wachttijd: ESWL bij blaasstenen

De behandeling van eerste keuze voor vesicale stenen is de transurethrale cystolithotripsie (TUCL). Door de COVID-19-pandemie kampen ziekenhuizen echter met lange wachttijden voor – onder meer – deze operaties. Daarnaast komen sommige patiënten niet in aanmerking voor een operatie door hun comorbiditeit. In de jaren negentig van de vorige eeuw was extracorporele shockwave lithotripsie (ESWL) een veel gebruikte, veilige behandelmethode voor blaasstenen. Toen TUCL effectiever bleek, is ESWL voor blaasstenen echter in de vergetelheid geraakt. ESWL is poliklinisch uit te voeren, waardoor wachttijden korter zijn dan die voor operatieve ingrepen. Gedurende de COVID-19-pandemie hebben we enkele patiënten met blaasstenen behandeld met ESWL. We concluderen dat ESWL een geschikt alternatief is voor de TUCL bij geselecteerde patiënten, maar dat voor een effectieve behandeling meerdere ESWL-procedures nodig zijn.

Influence of severity and level of injury on the occurrence of complications during the subacute and chronic stage of traumatic spinal cord injury: a systematic review

OBJECTIVE

Secondary health conditions (SHCs) are long-term complications that frequently occur due to traumatic spinal cord injury (tSCI) and can negatively affect quality of life in this patient population. This study provides an overview of the associations between the severity and level of injury and the occurrence of SHCs in tSCI.

METHODS

A systematic search was conducted in PubMed and Embase that retrieved 44 studies on the influence of severity and/or level of injury on the occurrence of SHCs in the subacute and chronic phase of tSCI (from 3 months after trauma). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed.

RESULTS

In the majority of studies, patients with motor-complete tSCI (American Spinal Injury Association [ASIA] Impairment Scale [AIS] grade A or B) had a significantly increased occurrence of SHCs in comparison to patients with motor-incomplete tSCI (AIS grade C or D), such as respiratory and urogenital complications, musculoskeletal disorders, pressure ulcers, and autonomic dysreflexia. In contrast, an increased prevalence of pain was seen in patients with motor-incomplete injuries. In addition, higher rates of pulmonary infections, spasticity, and autonomic dysreflexia were observed in patients with tetraplegia. Patients with paraplegia more commonly suffered from hypertension, venous thromboembolism, and pain.

CONCLUSIONS

This review suggests that patients with a motor-complete tSCI have an increased risk of developing SHCs during the subacute and chronic stage of tSCI in comparison with patients with motor-incomplete tSCI. Future studies should examine whether systematic monitoring during rehabilitation and the subacute and chronic phase in patients with motor-complete tSCI could lead to early detection and potential prevention of SHCs in this population.

A large renal bullet that resembles a large renal stone. A rare case scenario

Introduction

Genitourinary trauma secondary to a gunshot wound is uncommon as it only occurs in about 10% of cases. We present a case of a gentleman who suffered a gunshot wound to the kidney.

Presentation of case

A 28 year old man presented with irritative lower urinary tract symptoms (LUTs) since three months. The medical history was irrelevant. He is known case of neurogenic bladder maintained on regular clean intermittent catheterization (CIC). He has history of gunshot to the back since few years that resulted in spinal injury. CTUT showed retained bullet inside the right kidney that look alike hyperdense renal stone, Moreover, multiple vesical stones. The vesical stones were treated with cystolitholapaxy. Given that the patient is asymptomatic, conservative management for the retained right renal bullet is the feasible option.

Discussion

Based on the ASST classification, renal gunshot injury results in a grade IV injury. Abdominal exploration was reserved only in selected scenarios. Gunshot injuries to the kidney are commonly associated with thoracic and abdominal injuries. Gunshot injuries may be caused by low-velocity or high-velocity bullets. Given the paucity of cases reported in the literature, it is not obvious what is the optimum management of such patients with a retained renal bullet? We present the radiological findings and a clinical case summary as well for those who have Grade IV kidney injury and retained bullet managed conservatively.

Conclusion

Retained renal bullet post gunshot injury to the back is unusual presentation. A characteristic star-like pattern produced by lead shots and not by “stone,” consisting of plastic detonating cap will aid the urologist to differentiate retained renal bullet from renal stone. In such scenario, asymptomatic renal bullet look alike renal stone doesn't necessitate treatment.

Incidence of Renal Tract Abnormalities on Ultrasonography in Patients with Spinal Cord Injury: A Retrospective Pilot Study of a Military Cohort Undergoing Long-Term Institutional Rehabilitation

Study Design

Retrospective pilot study.

Purpose

To assess the incidence of renal tract abnormalities using ultrasonography (US) in a military cohort with traumatic spinal cord injury (TSCI) at a tertiary level spinal cord injury center.

Overview of Literature

Neurogenic bladder in TSCI patients results in significant urological morbidity. There is lack of data for these patients during the first 18 months of long-term rehabilitation in an institutional setting.

Methods

We retrospectively reviewed patient records to collect data on demographic characteristics, injury level, injury severity, time since injury, bladder management methods (such as an indwelling catheter [IC], clean intermittent catheterization [CIC], or self-voiding [S]); we correlated these data with the findings of the renal tract US.

Results

The study included 73 out of 81 male participants. The mean patient age was 29.99 years; the study group included 34.2% tetraplegics and 65.8% people with paraplegia. The time since injury was 6–12 months for 42.5% of the subjects and 12–18 months for 57.5% of the subjects. A normal US scan was recorded in 65.7% patients, and bladder trabeculation was the commonest finding in 15.1% of the subjects, followed by hydronephrosis (HDN) in 12.3%, and renal calculus and atrophy in 1.3% participants each. We found 22.22% of the IC group participants had higher US abnormalities than those in the reflex voiding group (statistically non-significant difference, p=0.7). Trabeculations (21.4%) and HDN (19%) were more common in those who had sustained the injury 12–18 months previously as compared to that in those who had injured themselves 6–12 months previously (p=0.04). The proportion of patients who had a normal US scan was higher in the group who sustained the injury 6–12 months previously versus those who had sustained the injury 12–18 months previously; the difference was statistically significant (p=0.02). There was no significant (p=0.72) correlation in the bladder management method, injury level, and renal tract abnormalities between the groups.

Conclusions

This retrospective study shows that 65% of TSCI participants had no renal tract abnormality on US scan and bladder trabeculation ruled out as the most common finding. Long-term supervised rehabilitation may help achieve good renal quality of life; however, further prospective trials are required on this subject.

Surveillance and management of urologic complications after spinal cord injury

PURPOSE

Neurogenic bladder due to spinal cord injury has significant consequences for patients' health and quality of life. Regular surveillance is required to assess the status of the upper and lower urinary lower urinary tracts and prevent their deterioration. In this review, we examine surveillance techniques in neurogenic bladder, describe common complications of this disease, and address strategies for their management.

METHODS

This work represents the efforts of SIU-ICUD joint consultation on Urologic Management of the Spinal Cord injury. For this specific topic, a workgroup was formed and comprehensive literature search of English language manuscripts regarding neurogenic bladder management was performed using key words of neurogenic bladder. Articles were compiled, and recommendations in the chapter are based on group discussion and follow the Oxford Centre for Evidence-based Medicine system for Levels of Evidence (LOEs) and Grades of Recommendation (GORs).

RESULTS

At a minimum, patients should undergo an annual history and physical examination, renal functional testing (e.g., serum creatinine), and upper tract imaging (e.g., renal ultrasonography). The existing evidence does not support the use of other modalities, such as cystoscopy or urodynamics, for routine surveillance. Urologic complications in neurogenic bladder patients are common and often more complex than in the general population.

CONCLUSIONS

There is a shortage of high-quality evidence to support any particular neurogenic bladder surveillance protocol. However, there is consensus regarding certain aspects of regular genitourinary system evaluation in these patients. Proper surveillance allows the clinician to avoid or address common urological complications, and to guide, alter, or maintain appropriate therapeutic regimens for individual patients.

Management of bladder stones: the move towards non-invasive treatment

Background: Bladder stone accounts for 5% of all cases of urolithiasis. Bladder stones management has evolved over the last decades from open bladder surgery (sectio alta) to intracorporeal cystholithotripsy as well as extracorporeal shock wave lithotripsy (ESWL). ESWL presents to be a promising modality in the management of bladder calculi due to its simplicity and well tolerability. This study is thus conducted to present data on the safety and effectiveness of ESWL in the management of bladder stone patients.Methods: This is a retrospective study evaluating the medical records of 92 bladder calculi patients admitted to Cipto Mangunkusumo General Hospital (RSCM) from January 2011 to April 2015. Patient’s age, gender, type of stone and procedure being done, status of stone disintegration, length of hospital stay, and any complications that may occur are noted down and statistically analyzed using SPSS v. 20.Results: Majority of the patients underwent ESWL (49 out of 92, 53.3%). The stone free rates for ESWL, intracorporeal lithotripsy, and sectio alta are 93.9%, 97.0% and 100% respectively. One patient had to repeat ESWL. The ESWL group had the smallest stone size average compared to the intracorporeal lithotripsy and section alta group (2.5 cm±2.0 cm vs 4.8 cm±3.7 cm vs 7.4 cm±5.4 cm respectively). The ESWL sessions were conducted in the outpatient clinic, and thus no hospital stay was required.Conclusion: ESWL can be suggested as an effective non-invasive approach in the disintegration of bladder stone of ≤25 mm with a promisingly high stone-free rate (93.9%) Furthermore, ESWL can be performed on an outpatient basis with minimal complications.

Sex-related differences of rehabilitation outcomes of spinal cord lesion patients

Objectives: To evaluate sex-related differences of spinal cord lesion patients.

Patients: Two hundred and eighty-one patients were included with evaluation of: lesion to admission time, aetiology, lesion level, associated injury, medical complications and surgical intervention, length of stay, American Spinal Injury Association (ASIA) impairment and motor scores.

Main outcome measures: ASIA impairment grade and ASIA motor scores; Barthel Index, Rivermead Mobility Index and Walking Index for Spinal Cord Injury.

Results: In the entire group female patients had a lower frequency of traumatic lesions, a lower frequency of complications at admission and a higher frequency of incomplete lesions (ASIA impairment C). In the matching cohorts comparison female patients showed the same neurological and functional recovery as male patients.

Conclusion: Gender does not seems to influence spinal cord rehabilitation outcomes despite the fact that men and women showed significant epidemiological differences. Further studies are needed to evaluate some aspects such as long-term bladder management and complications.

Morbidity associated with operative management of bladder stones in spinal cord-injured patients

STUDY DESIGN

Retrospective cohort study of spinal cord-injured (SCI) patients undergoing bladder stone removal operations between 1999 and 2013.

OBJECTIVES

To determine the morbidity associated with different operative management of bladder stones in SCI patients.

SETTING

National Spinal Injuries Unit, Stoke Mandeville Hospital, UK.

METHODS

Data on age, sex, level and Frankel classification of spinal cord injury, method of bladder drainage, method of bladder stone removal, complications and length of stay were collected from patient records. Complication was defined as bladder perforation, sepsis or persistent haematuria. Predictors of complications and length of stay were determined using univariate and multivariate regression analyses.

RESULTS

Overall, 112 consecutive bladder stone removal operations were performed, one open cystolithotomy and 111 transurethral procedures utilising simple washout, stone punch or electrohydraulic lithotripsy (EHL). Of these procedures, 17% (19/112) had complications; 0/11 (0%) following washout, 5/44 (11%) after stone punch, 3/12 (25%) following EHL and 10/26 (38%) after combined procedures using stone punch and EHL. In a multivariate model, patients with a cervical-level injury and those undergoing a combined procedure were significantly more likely to have a complication (P=0.032 and P=0.046). Length of stay was longer following a complication, the mean was 4.18 days compared with 1.37 days without a complication (P<0.001). Controlling complications and age, use of a combined procedure was associated with significantly longer stay than use of stone punch alone.

CONCLUSION

This study provides important outcome data that should guide operative procedure choice and inform patients about possible risks during consent. It sets a benchmark that other centres can evaluate their outcomes against.

Clinical complications of urinary catheters caused by crystalline biofilms: something needs to be done

This review is largely based on a previous paper published in the journal Spinal Cord. The care of many patients undergoing long-term bladder catheterization is complicated by encrustation and blockage of their Foley catheters. This problem stems from infection by urease-producing bacteria, particularly Proteus mirabilis. These organisms colonize the catheter forming an extensive biofilm; they also generate ammonia from urea, thus elevating the pH of urine. As the pH rises, crystals of calcium and magnesium phosphates precipitate in the urine and in the catheter biofilm. The continued development of this crystalline biofilm blocks the flow of urine through the catheter. Urine then either leaks along the outside of the catheter and the patient becomes incontinent or is retained causing painful distension of the bladder and reflux of urine to the kidneys. The process of crystal deposition can also initiate stone formation. Most patients suffering from recurrent catheter encrustation develop bladder stones. P. mirabilis establishes stable residence in these stones and is extremely difficult to eliminate from the catheterized urinary tract by antibiotic therapy. If blocked catheters are not identified and changed, serious symptomatic episodes of pyelonephritis, septicaemia and endotoxic shock can result. All types of Foley catheters including silver- or nitrofurazone-coated devices are vulnerable to this problem. In this review, the ways in which biofilm formation on Foley catheters is initiated by P. mirabilis will be described. The implications of understanding these mechanisms for the development of an encrustation-resistant catheter will be discussed. Finally, the way forward for the prevention and control of this problem will be considered.

Bladder stones in patients with spinal cord injury: a long-term study

STUDY DESIGN

Retrospective follow-up study.

OBJECTIVES

To assess the occurrence of bladder stones in patients with spinal cord injury (SCI).

SETTING

Single SCI rehabilitation center in Switzerland.

METHODS

We searched our database for SCI patients who had undergone surgery due to bladder stones between 2004 and 2012. In all patients retrieved, personal characteristics, bladder management, bladder stone occurrence and time to stone formation/recurrence were recorded.

RESULTS

We identified 93 (3.3%) of 2825 patients with bladder stones, 24 women and 69 men, with a mean age 50 years (17-83) years. We observed bladder stones in patients with suprapubic catheter (SPC) in 11% (50/453), transurethral catheter (TC) in 6.6% (5/75), with intermittent catheterization (IC) in 2% (27/1315) and with reflex micturition (RM) in 1.1% (11/982), respectively. The mean time period to stone development was 95 months. The TC group had the shortest time interval (31 months), followed by the SPC group (59 months), individuals performing IC (116 months) and RM (211 months), respectively. Bladder stone recurrence rate was 23%. Recurrences were most frequent in the TC group (40%), followed by SPC (28%) and IC (22%), whereas no recurrences occurred in the RM group. Time to recurrence was shortest in the SPC group (14 months), followed by the IC (26 months) and the TC group (31 months), respectively.

CONCLUSION

In SCI patients, bladder management has an important role in the development of bladder stones. Indwelling catheters (TC/SPC) are associated with the highest risk to develop bladder stones and therefore should be avoided if possible. If unavoidable, SPC are superior to TC.

The management of bladder lithiasis in the modern era of endourology

The recent evolution in the management of vesical lithiasis is a result of the major advancements of modern endourology. The ideal method for achieving stone clearance, however, remains an issue of debate and evidence-based recommendations are lacking. Contemporary literature focuses on management options, such as extracorporeal shockwave lithotripsy, transurethral, percutaneous and minimally-invasive surgery, as well as state-of-the-art energy sources. Issues of particular interest include the results of comparative studies, the management of lithiasis in the paediatric population and the recent challenge of the traditional dogma that dictated BPH surgery for the management of vesical lithiasis secondary to bladder outlet obstruction.

The encrustation and blockage of long-term indwelling bladder catheters: a way forward in prevention and control

OBJECTIVES

To review the literature showing that understanding how Foley catheters become encrusted and blocked by crystalline bacterial biofilms has led to strategies for the control of this complication in the care of patients undergoing long-term indwelling bladder catheterization.

METHODS

A comprehensive PubMed search of the literature published between 1980 and December 2009 was made for relevant articles using the Medical Subject Heading terms 'biofilms', 'urinary catheterization', 'catheter-associated urinary tract infection' and 'urolithiasis'. Papers on catheter-associated urinary tract infections and bacterial biofilms collected during 40 years of working in the field were also reviewed.

RESULTS

There is strong experimental and epidemiological evidence that infection by Proteus mirabilis is the main cause of the crystalline biofilms that encrust and block Foley catheters. The ability of P. mirabilis to generate alkaline urine and to colonize all available types of indwelling catheters allows it to take up stable residence in the catheterized tract in bladder stones and cause recurrent catheter blockage.

CONCLUSION

The elimination of P. mirabilis by antibiotic therapy as soon as it appears in the catheterized urinary tract could improve the quality of life for many patients and reduce the current expenditure of resources when managing the complications of catheter encrustation and blockage. For patients who are already chronic blockers and stone formers, antibiotic treatment is unlikely to be effective owing to the resistance of cells in the crystalline biofilms. Strategies such as increasing fluid intake with citrated drinks could control the problem until bladder stone removal can be organized.

Prevalence and epidemiologic characteristics of lower urinary tract stones in Japan

OBJECTIVES

To analyze the changes in the annual incidence and epidemiologic details of lower urinary tract stones in Japan, a nationwide survey of urolithiasis was performed.

METHODS

Data were obtained from all patients who had been diagnosed by urologists in 2005 as having lower urinary tract stones, including both first and recurrent stones. The data were separately enumerated according to hospital size, irrespective of admission and treatment. The study included all hospitals approved by the Japanese Board of Urology and thus covered nearly all urologists practicing in Japan. The estimated annual incidence according to sex, age, and stone composition was compared with other nationwide surveys taken from 1965 to 1995.

RESULTS

The incidence of lower urinary tract stones in Japan has steadily increased from 4.7/100,000 in 1965 to 9.1/100,000 in 2005. However, the age-standardized annual incidence of lower urinary tract stones in Japan decreased slightly from 5.5/100,000 in 1965 to 5.4/100,000 in 2005. The incidence of stones containing calcium has significantly increased from 50.7% to 72.0% among men and the incidence of infection-related stones has decreased significantly from 26.2% to 10.1%. The ratios of uric acid calculi in men and of infection-related stones in women increased with age.

CONCLUSIONS

The increased incidence of lower urinary tract stones is in slight contrast to the sudden increase in the incidence of upper urinary tract stones, which might be associated with the aging of the Japanese population.

Health of community-dwelling adults with mobility limitations in the United States: incidence of secondary health conditions. Part II

OBJECTIVE

To compare incident health conditions that occurred over a 2-year period in nationally representative groups of adults with mobility, nonmobility, and no limitations.

DESIGN

Data were collected prospectively from a probability subsample of households that represent the civilian, noninstitutionalized U.S. population.

SETTING

Five rounds of household interviews were conducted over 2 years.

PARTICIPANTS

Data were analyzed on the same respondents from the 1996-1997 Medical Expenditure Panel Survey (MEPS) and the 1995 National Health Interview Survey Disability Supplement. Respondents were categorized into 3 groups for analysis; those with mobility limitations, nonmobility limitations, and no limitations. The analytic sample included 12,302 MEPS adults (>/=18y).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Number, types, and 2-year incidence of self-reported health conditions compared across groups.

RESULTS

The mean number of incident conditions (95% confidence intervals [CIs]) over the 2-year period was greatest in adults with mobility limitations (mean, 4.7; 95% CI, 4.4-4.9) compared with those with nonmobility limitations (mean, 3.9; 95% CI, 3.7-4.2) or no limitations (mean, 2.6; 95% CI, 2.5-2.7). Incident conditions affected most major body systems.

CONCLUSIONS

Because secondary conditions are potentially preventable, determining factors that influence their occurrence is an important public health issue requiring specific action.

Urinary calculi following traumatic spinal cord injury

OBJECTIVE

To investigate the time aspect of the development of renal and bladder calculi in individuals with traumatic spinal cord injury (SCI) and a possible relation between the development of calculi and the bladder-emptying method.

MATERIAL AND METHODS

The study comprised a retrospective data collection from medical records and a questionnaire follow-up at least 10 years after the SCI.

RESULTS

A total of 236 individuals with SCI (82% male, 18% female; 47% tetraplegic, 53% paraplegic) who were injured between 1956 and 1990 participated in the study and the response rate was 84.6%. The mean age at the time of follow-up was 50.5 years (range 28-84 years). The mean duration from the time of SCI was 24.1 years (range 10-45 years). During follow-up 47 participants (20%) had at least one episode of renal calculi and 32 (14%) had at least one episode of bladder calculi. The risk of first renal and bladder calculus was highest within the first 6 months post-injury. The cumulative proportion of calculi-free participants 45 years post-injury was 62% for renal calculi and 85% for bladder calculi. For participants who did not develop renal calculi within the first 2 years post-injury, the risk of having a renal calculus within the next 43 years was 34%. For bladder calculi the corresponding risk of having a bladder calculus within the next 43 years was 5%. No significant differences were found regarding the bladder-emptying method and either renal or bladder calculi, only a non-significant trend that more participants with bladder calculi used indwelling catheters. Participants with renal or bladder calculi were not statistically significantly different from the remainder of the study group regarding gender, para- or tetraplegia or Frankel classification.

CONCLUSIONS

The risk of developing renal and bladder calculi was higher in the SCI population compared to the normal population. Bladder calculi primarily occur early post-injury and renal calculi appear both early post-injury and years later. Therefore, it is important to follow individuals with SCI regularly by means of urological investigations from the time of the injury until death.

Risk factors for urinary stone formation in men with spinal cord injury: a 17-year follow-up study

OBJECTIVE

To establish hazard ratios for risk of urinary stone formation in men with chronic spinal cord injury.

PATIENTS AND METHODS

In all, 140 men injured before 1987 were eligible for this investigation and were followed yearly from January 1987 and December 2003.

RESULTS

Over the 17 years, 39 patients (28%) and 21 (15%) were diagnosed with bladder and renal stones for a total of 59 and 25 episodes, respectively. In multivariate analysis, bladder stone was more common in patients injured when aged > or = 24 years than in those injured when aged <24 years (odds ratio 2.5; 95% confidence interval 1.1-5.7; P = 0.03). In another model, patients with complete injury had a greater risk of renal stone formation than those with incomplete injury (4.1, 1.3-12.9; P = 0.016). Renal stone was more common for patients with urethral catheterization than for those voiding spontaneously (5.7, 1.3-24.6, P = 0.021) and for patients with bladder stone than for those without (4.7, 1.5-15.1; P = 0.01).

CONCLUSION

Injury characteristics are important for the development of urinary stone in chronic traumatic spinal cord injury. In addition, the present findings suggest that in men who cannot use intermittent catheterization or when the bladder cannot empty spontaneously, suprapubic cystostomy is better than urethral catheterization to avoid renal stone formation.

Urolithiasis in patients with spinal cord injuries: risk factors, management, and outcomes

PURPOSE OF REVIEW

Despite major advances in the urological care of spinal cord injury patients, the incidence of urolithiasis has not changed. Although the incidence of kidneys lost to staghorn calculus disease has decreased considerably, stone disease is still a significant cause of morbidity and concern. The purpose of this review is to summarize the risk factors for the development of stone diseases in the spinal cord injury patient population and present the outcomes of current endourologic treatment modalities.

RECENT FINDINGS

Recurrent urinary tract infections, indwelling catheters, vesicoureteral reflux, and immobilization hypercalcuria are a few of the major risk factors for the development of urolithiasis among spinal cord injury patients. Retrograde endourologic techniques are often not possible to address stone disease due to lower extremity contractures, spinal curvature, and pelvic tilt. Extracorporeal shockwave lithotripsy success rates vary from 50 to 90%, but clearance rates are often delayed. Success rates for percutaneous nephrolithotomy match those quoted in the general population ( > 90%), but at the expense of a higher rate of complications (6-20%). Meticulous planning with regard to appropriate prophylactic antibiotics and body position will maximize efficacious outcomes.

SUMMARY

Early identification and treatment of urolithiasis in spinal cord injury patients will aid in preserving renal function and minimizing associated complications. Despite variation in common urological practices between spinal cord injury units and the lack of clear cut guidelines for follow-up, the increased incidence of risks associated with urolithiasis lends support for routine genitourinary imaging in order to identify and treat those individuals at highest risk.

Surface free energy effect on bacterial retention

Bacterial infection is one of the most frequent and severe complications in the long-term effectiveness of medical implants and devices, greatly increasing treatment cost and inconvenience to the patient. Surface physical and chemical properties are known to influence the extent and form of bacterial infection, although the exact correlation with specific properties is difficult due to the complexity of the system. One approach in the attempt to reduce the bacterial colonisation is to modify the surface energy and chemistry, so as to influence the interactions between the surface and the bacteria that come into contact with it. Five types of coatings were investigated in this study, together with silicone, and polished and non-polished stainless steel 316L. Surfaces were tested for retention of Pseudomonas aeruginosa AK1 after 1h. A good correlation (>90%) was found between P. aeruginosa AK1 retention and total surface free energy, as well as its polar and dispersive components. The minimum level of P. aeruginosa AK1 retention was found for a range of total surface free energy in the range 20-27 mN/m.

Does fluid amount and choice influence urinary stone formation in persons with spinal cord injury?

OBJECTIVE

To examine the effects of fluid intake and beverage type on stone formation in persons with spinal cord injury (SCI).

DESIGN

A matched case-control study.

SETTING

A rehabilitation center within a university hospital.

PATIENTS

Forty-one patients with SCI who were diagnosed with urinary stones between 1992 and 1998 (stone cases) and 171 age- and duration-matched controls were interviewed by telephone.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Urinary stones.

RESULTS

Stone cases were more likely than controls to be white, to be current smokers, to be users of indwelling catheterization, and to have a lower body mass index (kg/m(2)), worse renal function, and higher urine specific gravity (P<.10). In a multivariable model that adjusted simultaneously for other possible risk factors, the greater consumption of juice (>207mL/d) was associated with a 70% decreased risk (odds ratio=0.3; 90% confidence interval, 0.1-1.0). An interesting, but not significant (P=.15), increased risk for coffee consumption was observed. There was no association for total fluid intake.

CONCLUSION

Total fluid intake does not appear to determine stone occurrence; however, fluid type may influence stone formation in persons with SCI. Further study is required to verify these findings, thus possibly leading to an effective fluid regimen for stone prophylaxis.