Accuracy of ultrasonic detection of renal scarring in different centres using DMSA as the gold standard.

BACKGROUND: There is an ongoing debate over the radiological investigations of children with urinary tract infections (UTIs) with some authorities suggesting that ultrasound scan (USS) alone is an accurate tool to diagnose renal parenchymal scarring post-pyelonephritis. All studies on this subject have been performed at paediatric teaching centres whereas most children with UTIs are managed by General Paediatricians in District General Hospitals (DGHs) in the United Kingdom. We wished to identify whether results of scans in DGHs differed from those in teaching centres. METHODS: We looked at all children with a clinical history of UTIs having a DMSA and USS over a one year period in two DGHs and one teaching centre. A total of 476 children's results were reviewed, 297 from the DGHs and 179 from the teaching centre. RESULTS: The cohort had a total of 949 renal units. There were 79 scarred renal units (kidneys) on DMSA (8%) in 72 patients (15%). Just 18 renal units were detected as being scarred on USS (22.8%). Nine of 32 scarred renal units in the teaching centre were detected compared with nine of 47 in the DGHs (P = 0.40). Thirty-nine (49%) of the scarred renal units were in patients >5-years old. Of these 12 (30.7%) were detected on USS, nine of 17 within the teaching centre compared with just three of 22 at the DGHs (P = 0.01). CONCLUSION: Overall only a small percentage of scars are detected on USS. In the over 5-year old group, where USS alone might be preferred, DGHs were significantly worse at detecting scarred kidneys. We conclude that if the detection of renal scars is a prime reason for imaging in children with UTIs, ultrasonography alone is inappropriate at any age and DMSA ought to be the primary investigation.     

Dimercaptosuccinic acid (DMSA) renal scan in the evaluation of hypertension in children

Renal scarring is known to be associated with hypertension. The primary objective of this study was to investigate the prevalence of renal scarring in children referred to our clinic with hypertension. The secondary objective was to compare renal ultrasound (US) examination with dimercaptosuccinic acid (DMSA) renal scan in diagnosing renal scars in these patients. The study included 159 patients who underwent DMSA renal scan as well as renal US for the evaluation of hypertension of unknown etiology. Thirty-three (21%) patients were found to have renal scars; their demographic details, including mean age and gender distribution, were not significantly different from those without renal scars. In comparison with the DMSA renal scan, sensitivity and specificity of renal US in diagnosing renal scars were 36% and 94%, respectively. In our study, in which the prevalence of scarring was 21%, this gave positive predictive and negative predictive values of 63% and 85%, respectively. In conclusion, our study indicates that renal scarring is present in 21% of otherwise healthy children who are evaluated for newly diagnosed hypertension, and renal US is not a sensitive imaging modality to rule out renal scarring.     

Urography versus DMSA scan in children with vesicoureteric reflux

Following the diagnosis of primary vesicoureteric reflux, identified as part of the investigation of urinary tract infection, 299 refluxing kidneys in 202 children (aged 0–14 years) were prospectively evaluated using intravenous urography (IVU) and the DMSA renal scan at least 4 weeks after urine infection. There was 88% concordance between IVU and the DMSA scan, but in 12% there were discrepancies manifested in 37 kidneys from 31 children. Thirty-four kidneys were normal on IVU but showed scars of reflux nephropathy (RN) on the technetium 99m-dimercaptosuccinic acid (DMSA) renal scan; 4 of these (2 infants and 2 pre-school children) had severe generalized changes on scanning. Three kidneys were normal of DMSA scan and, although abnormal on initial IVU, were considered to be normal when this was repeated. During a followup period of 5 years an annual DMSA was undertaken in 194 patients and the renal scars remained unchanged in all except 1 child. The IVU was repeated 1–3 years after the initial study in 31 children in which the results of the first imaging did not agree. In 28 patients (34 kidneys) in which the initial IVU was normal but the DMSA abnormal, IVU evidence of scarring emerged in 30 of 34 kidneys, including the 4 patients with severe generalized damage on the DMSA. We conclude that abnormalities detected by the DMSA scan may precede the radiological findings, especially in young children. Even severe RN can be established in kidneys that appear normal on the IVU.     

Procalcitonin as a predictor of renal scarring in infants and young children

The aim of this study was to evaluate the usefulness of procalcitonin (PCT) as a marker of renal scars in infants and young children with a first episode of acute pyelonephritis. Children aged 7 days to 36 months admitted for first febrile urinary tract infection (UTI) to a pediatric emergency department were prospectively enrolled. The PCT concentration was determined at admission. Acute ^99mTc-dimercaptosuccinic acid (DMSA) scintigraphy was performed within 7 days of admission and repeated 12 months later when abnormal findings were obtained on the first scan. Of the 72 children enrolled in the study, 52 showed signs of acute pyelonephritis (APN) on the first DMSA scan. A follow-up scintigraphy at the 12-month follow-up performed on 41 patients revealed that 14 (34%) patients had developed renal scars; these patients also presented significantly higher PCT values than those without permanent renal lesions [2.3 (interquartile range 1–11.6) vs. 0.5 (0.2–1.4) ng/mL; p = 0.007]. A comparison of the PCT concentration in patients with febrile UTI without renal involvement, with APN without scar development and with APN with subsequent renal scarring revealed a significant increasing trend (p = 0.006, Kruskal–Wallis test). The area under the ROC curve for scar prediction was 0.74 (95% confidence interval 0.61–0.85), with an optimum statistical cut-off value of 1 ng/mL (sensitivity 78.6%; specificity 63.8%). Based on these results, we suggest that serum PCT concentration at admission is a useful predictive tool of renal scarring in infants and young children with acute pyelonephritis.     

The Use of Ultrasonography in Evaluating Adults with Febrile Urinary Tract Infection

Background.?Urinary tract infection (UTI) is a common disease. Controversy exists about the role of radiological evaluation in the patient with urinary tract infection. Materials and Methods.?From 04 2001 to 12 2001, patients with febrile UTI admitted to Chang Gung Memorial Hospital, Chiayi were prospectively evaluated by ultrasonography. The inclusion criteria of febrile UTI was a body temperature of more than 38°C with a bacterial count of 10³ or more per mL in a freshly voided midstream or catheterized urine. Results.?A total of 94 patients were evaluated and all patients recovered. Major abnormal sonograms were present in 17 (18%) of the patients. A history of urolithiasis and a duration of fever ≥ 3 days after admission were statistically significant clinical parameters in predicting major abnormal sonogram. Although diabetes mellitus was not statistically significant in predicting major abnormal sonogram, diabetic patients had 2.5 times the likelihood of major structural abnormalities than nondiabetic patients. Conclusion.?Ultrasonographic study of patients with febrile UTI should be limited only to those with a duration of fever ≥ 3 days and a history of urolithiasis. Ultrasonographic study should also be considered in febrile UTI patients with diabetes mellitus     

Preliminary study on the prevention of recurrent urinary tract infection in adult women using intravaginal Lactobacilli

We now report the development of gelatin suppositories containing freeze dried Lactobacillus casei GR-1 and L. fermentum B-54 chosen for their ability to adhere to uroepithelial cells and inhibit the growth of E. coli and Enterococcus faecalis in vitro. The product has a long shelf life, and is easily and safely utilized. In a preliminary study of 10 female patients who received the therapy at weekly intervals for 12 months, there was a net reduction of 66.3% in the incidence of recurrent urinary tract infections. Lactobacilli were isolated from the vagina of the patients for the duration of treatment. Examination of random specimens showed some degree of correlation between numbers of lactobacilli adherent to vaginal epithelial cells and viable organisms recovered from swabs.     

Long-term prognosis of post-infectious renal scarring in relation to radiological findings in childhood — a 27-year follow-up

In a previous report the long-term prognosis of 30 patients with renal scarring after pyelonephritis in childhood was described. In this study, we have related the extent of renal scarring present in childhood to the conditions in early adulthood. A radiological progression of searring from childhood to adulthood was seen in one-third of the kidneys. The 7 patients with bilateral scarring in childhood had a smaller renal area, lower glomerular filtration rate and higher plasma vasopressin at follow-up than 13 healthy controls. The 20 patients who had unilateral searring in childhood had a smaller renal area, lower glomerular filtration rate, higher diastolic blood pressure and higher plasma renin at follow-up than controls; 4 had hypertension. The most important finding was that children with unilateral disease are at risk of serious long-term complications. Filtration fraction at follow-up was higher in patients with extensive renal scarring in childhood compared with those with a normal renal area or small scars in childhood (r=–0.43,P<0.05). This may indicate glomerular hyperfiltration by remnant glomeruli. This paper emphasizes the potential seriousness of childhood urinary tract infections especially when early infantile infections are overlooked. A follow-up of more than 4 decades may be necessary before the ultimate prognosis can be established, especially in patients with unilateral renal disease. It is advised that most patients with post-infectious renal scars are followed as high-risk patients, and that treatment continuity is established between paediatricians, nephrologists and, when required, obstetricians.to Author for further revision and received in revised form May 28, 1991     

Acute pyelonephritis and renal scarring in Kuwaiti children: a follow-up study using 99mTc DMSA renal scintigraphy

The aim of this study was to determine the prevalence of renal scarring in a group of Kuwaiti Arab children with their first documented acute pyelonephritis (APN). Eighty-two Kuwaiti Arab children (10 males and 72 females) who had abnormal ^99mTc DMSA renal scan findings of acute pyelonephritis were prospectively studied with the same imaging modality 6 months after treatment to identify those who developed renal scarring. A micturition cystourethrogram (MCUG) was performed for all of the children 1 month after diagnosis. Children were divided into 3 age groups (<2 years, 2–5 years and above 5 years). The follow-up DMSA renal scans 6 months after diagnosis revealed normalization of renal changes in 56% (46 patients), much improvement with residual renal abnormality in 6% (5 patients), and persistent parenchymal defects in 38% (31 patients). Vesicoureteric reflux (VUR) was found in 32% of children (26/82) and the majority were between grade I and III. Thirteen of those with VUR (50%) developed renal scars on follow-up. Fifty-three percent of the scarred kidneys (19/36) were drained by non-refluxing ureters. In this study, children older than 2 years had less VUR yet were more susceptible to APN and to the development of renal scars. Girls were more prone to developing APN and renal scarring than boys. This work shows that APN is a serious cause for renal scarring in our patients, particularly if associated with other risk factors such as recurrent infections and the female sex.     

Urinary infection,reflux and renal scarring in females continuously followed for 13–38 years

This study describes the pattern of urinary tract infections (UTI) in 87 females prospectively followed for a median of 23 years from their first recognized symptomatic infection in childhood. At 16 years of age they were selected for follow-up into adulthood because of renal scarring (reflux nephropathy) in 45 and recurrent UTI in 42. The attack rate (number of urinary tract infections per individual per observation year) was highest during the 1st year of life (1.9), with a gradual decrease to the lowest rate (0.2) at age 11–15 years. A moderately increased attack rate (0.4), was seen in the late teens, extending through to the mid twenties. The proportion of infections having a pyelonephritic character decreased with age and number of infection episodes, but not in females with severe renal scarring. Pyelonephritic infections were correlated with vesicoureteric reflux, and renal scarring to low age at the index infection, total number of pyelonephritic episodes and reflux. Females with renal scarring continued to have a high proportion of pyelonephritic recurrences after 10 years of age, implying that they risk progressive renal disease and should be closely followed into adulthood.     

Procalcitonin for the early prediction of renal parenchymal involvement in children with UTI: preliminary results

In order to establish the most reliable marker for distinguishing urinary tract infections (UTI) with and without renal parenchymal involvement (RPI), we recorded the clinical features and admission leukocyte count, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and serum procalcitonin (PCT) in 57 children (including 43 girls) aged 2–108 months admitted with a first episode of UTI. RPI was evaluated by Tc-99m dimercaptosuccinic acid (DMSA) scintigraphy within 7 days of admission. To establish cut-off points for ESR, CRP, and PCT, we used receiver operating characteristics curves and compared the area under the curve for ESR, CRP, and PCT. Twenty-seven children were diagnosed as having RPI based on positive renal scintigraphy. A body temperature of >38°C, a history of diarrhea, and poor oral intake were more common in patients with RPI. ESR, CRP, and PCT, but not leukocyte count, were significantly higher in patients with RPI (P < 0.001). PCT was more sensitive and specific for the diagnosis of upper versus lower UTI than ESR and CRP. Using a cut-off value of 0.85 ng/ml, PCT had the best performance, with sensitivity, specificity, and positive and negative predictive values of 89%, 97%, 96%, and 91% respectively. Serum PCT is a better marker than ESR, CRP, and leukocyte count for the early prediction of RPI in children with a first episode of UTI.     

Reliability of contrast enhanced sonography with harmonic imaging for detecting early renal scarring in experimental pyelonephritis in a porcine model: preliminary results

PURPOSE: Contrast medium enhanced harmonic ultrasound is a recently developed ultrasound technique that improves the assessment of renal parenchymal vascularity. We performed a preliminary study to define the ability of contrast enhanced ultrasound with harmonic imaging to detect and localize renal scars in a porcine model of experimentally induced pyelonephritis. MATERIALS AND METHODS: Vesicoureteral reflux was surgically induced in 10 pigs weighing 10 kg. with the contralateral kidney serving as a control. Approximately 4 weeks after the creation of vesicoureteral reflux cystography confirmed reflux. Infection was induced by placing a suspension of paraffin broth impregnated with Escherichia coli in the bladder of each pig. At 4 to 8 weeks (mean 6.5) after the induction of infection a radiologist blinded to the side of the previous procedure performed conventional gray scale ultrasound, color Doppler ultrasound and contrast enhanced ultrasound with harmonic power imaging. The animals were sacrificed; the kidneys were inspected and tissues from the upper, mid and lower poles were sent for culture and histological examination. Histology results were compared with the findings of the 3 ultrasound modalities. RESULTS: All 10 pigs survived the surgical procedures with no complications. Post-contrast harmonic ultrasound images were available in 9 pigs (18 renal units). Harmonic ultrasound revealed decreased blood flow in 11 renal units, including the upper pole in 7, lower pole in 3, and upper and lower poles in 2. Renal tissue cultures were positive in 11 renal units (6 refluxing units). Histological findings revealed fibrosis in 10 renal units (8 refluxing units). Harmonic ultrasound findings in these 10 renal units showed 9 with changes consistent with inflammation or scars. Using histological results as the gold standard for renal injury harmonic ultrasound was more sensitive than gray scale ultrasound for detecting renal injury with 90% sensitivity, 75% specificity, 81% positive predictive value and 85% negative predictive value. CONCLUSIONS: Preliminary results indicate that contrast enhanced ultrasound with harmonic imaging is a sensitive method for determining renal scarring without the need for radiation exposure. It may be prove to be a useful adjunct for evaluating children who present with urinary tract infection.     

The battle of the bladder: The pathogenesis and treatment of uncomplicated cystitis

An ecological approach to the pathogenesis of uncomplicated urinary tract infections allows awareness of the continual battle being waged in the vagina, urethra, and bladder between the bacterial invaders and the host defense mechanisms. Despite overwhelming odds, the bacteria must be able to persist, colonize, and finally adhere to these various battlefields on their ascent to the bladder itself. The large number of patients presenting to physician offices with acute simple cystitis attests to the fact that the bacteria occasionally win the battle of the bladder. An understanding of the pathophysiology of this constantly raging battle may help us modify our clinical approach to women with simple uncomplicated urinary tract infections.     

The effect of repeated instillations of antiseptics on catheter-associated urinary tract infections: a study in a physical model of the catheterized bladder

Summary The activity of three antiseptic bladder washout solutions was examined in a physical model of the catheterized bladder. Tests were performed against cultures of four common urinary tract pathogens that had established themselves in the model and colonized the surfaces with biofilm. Double instillations of chlorhexidine (0.02% w/v) at 6-h intervals failed to eliminate Pseudomonas aeruginosa, Proteus mirabilis, and Providencia stuartii from the bladder model. Escherichia coli, however, was susceptible to a second instillation provided that it was performed within 12 h. Supplementing chlorhexidine with EDTA and TRIS potentiated its activity against E. coli. Mandelic acid (1.0% w/v) was the most effective of the agents, double instillations eliminating all but Pr. mirabilis infections.     

Management of the Urologic Sepsis Syndrome

In approximately one-third of patients with sepsis, the source of infection is the urinary tract. The management of sepsis has rapidly changed over the past two decades, and a review of urosepsis management is paramount. It is estimated that in 30% of patients with severe sepsis and septic shock, the underlying reason is a urinary tract infection (UTI). The prevalence of microbiologically proven urosepsis in urology departments has been reported as 1.5% (quarter of health care–associated UTIs). On a global level, it has been postulated that 5.4 million deaths occur due to sepsis. The main causes of urosepsis are indwelling urinary catheters and urologic interventions (stone treatment, prostate biopsies, and endoscopic urethral stricture treatment). Urosepsis-causative pathogens are primarily gram-negative bacteria; this is different from sepsis overall, which is dominated by gram-positive bacteria. Its been reported that the resistance rates of pathogens in urosepsis are >10% for almost all antibiotics. The main principles of management of urosepsis and sepsis are the same, including early goal-directed treatment and antibiotic administration within the first 45 min. Early goal-directed therapy was recently shown not to be superior to standard care; however, these results may not be applicable to settings in which standard care needs improvement. Selection of an appropriate antibiotic for the initial empirical treatment in urosepsis requires knowledge of previous interventions, antibiotic usage, and local resistance rates. Future research on the management of urosepsis should be directed toward identification of groups at risk of developing urosepsis, antibiotic selection, and value of biomarkers in treatment response (eg, lactate, procalcitonin).Patient summaryIn approximately one-third of patients with sepsis, the source of infection is the urinary tract. This review assessed causes and management of urosepsis and directions for future research.     

先锋美他醇治疗泌尿生殖系感染：附150例报告

自１９９４年８－１０月，单儿采用先镁美他醇治疗泌尿生殖系统感染患者１５０例取得较好疗效。剂量：每日２－４ｇ溶于０．９％生理盐水或５％葡萄糖溶液中分两次静脉滴入，每次１０－１５分钟，连续用药３－１０天，结果：症状缓解有效率达９４％以上，对脓尿的效率为９５．３％，中段尿细菌培养阴转率为８１．４％，总有效率８７．３％。     

Ultrasonography as a predictor of overt bleeding after renal biopsy

Background  Renal biopsy is essential for the diagnosis of kidney diseases, but complications, particularly bleeding incidents, remain problematic. Methods  To evaluate the frequency of renal biopsy complications, and to reveal clinical and laboratory factors associated with overt bleeding complications, focusing on those available at hospital ward, we conducted a retrospective observational study for the period between 2001 and 2005 at Mie University Hospital in patients who underwent percutaneous renal biopsy of a native kidney. Of a total of 323 patients, 317 met the inclusion criteria. Results  Only one patient (0.3%) required blood transfusion or intervention to stop bleeding. The mean decrease in hemoglobin (Hb) after biopsy was 0.43 ± 0.7 g/dL. Hb decreased ≥1.0 g/dL in 66 patients (20.8%) and ≥10% in 32 patients (10.1%). On ultrasonography, perirenal hematoma was detected immediately after biopsy in 273 patients (86.1%), and 41 patients (12.9%) showed hematoma ≥2 cm in width. Analgesics were required for back pain in 67 patients (21.1%). Vasovagal response developed in 31 patients (9.8%). Macrohematuria occurred in 12 patients (3.8%). Urinary catheter was used in 161 patients (50.8%). For Hb decrease ≥10% after biopsy, multivariate analysis revealed perirenal hematoma (≥2 cm) as a significant factor. Other significant factors were prolonged international normalized ratio of prothrombin time, elevated blood pressure on hospital admission, older age, increased serum creatinine level, and steroid use. Conclusion  Perirenal hematoma ≥2 cm on ultrasonography immediately after biopsy might well represent a predictive factor for bleeding complications.     

Haemophilus influenzae acute pyelonephritis in the elderly

Haemophilus influenzae has rarely been implicated as the causative agent of urinary tract infections in adults. We report a case of H. influenzae pyelonephritis in a 78-year old man with benign prostatic hyperplasia and discuss the possible underestimation of the true incidence of H. influenzae in adult urinary tract infections.