Evaluation of the use of DMSA in culture positive UTI and culture negative acute pyelonephritis

This prospective study was done to assess the frequency of acute pyelonephritis (APN) in febrile children with positive urine culture as documented by Tc99m DMSA scintigraphy (DMSA) and the frequency of vesicoureteric reflux (VUR) in these children. Secondly, to determine the frequency of APN, in febrile children with supportive evidence for UTI but with negative urine culture, as documented by DMSA and frequency of VUR in them. Thirdly to stress the utility of DMSA to diagnose APN in urine culture negative febrile children and to suggest DMSA as a clinical tool in evaluation of fever of unknown origin (FUO). This study included 42 children with positive urine culture and 26 children with negative urine culture who had supportive evidence of UTI as determined by the predetermined criteria and diagnosed to have APN by DMSA. All of them had ultrasonogram (USG), DMSA and voiding cystourethrogram (VCU). They were followed up for a minimum period of 6 months. Out of the 42 children with positive urine culture 92.9% had features of APN in the DMSA of whom 82.1% had vesicoureteric relux (VUR). The DMSA was abnormal in 26 children with negative urine culture, of whom 65.4% had VUR. Ultrasound suggestive of parenchymal change was observed in 47.6% in the culture positive group and 65.4% in the culture negative group. In conclusion, it is suggested, that DMSA is a useful investigation for the diagnosis of APN in febrile UTI. DMSA is indicated in febrile children with negative urine culture but with supportive evidence of UTI and in FUO. An abnormal DMSA is a strong indication for work up for VUR.     

Could prophylactic antibiotics be stopped in patients with history of vesicoureteral reflux?

ObjectiveTo compare the incidence and type of urinary tract infection (UTI) in patients with primary vesicoureteral reflux (VUR) diagnosed after a febrile UTI while they were on prophylactic antibiotics (PA) and after stopping PA.Materials and methodsCriteria to discontinue PA were: no UTI during 12+ or more months on PA, old enough to communicate UTI symptoms, potty trained and absence of risk factors for UTI. Patients with at least 1 year of follow up without PA were included (n = 77). We recorded: age at which PA was indicated and stopped, time on and off PA, incidence and type of UTI (cystitis vs acute pyelonephritis (APN)), and renal scan results.ResultsPA was started and stopped at a mean age of 18.5 and 61 months, respectively. Mean time on PA was 39 months (range 12–95): 25 patients had 44 UTI episodes (0.17 episodes/patient/year), and 31 (70%) of them were APN. Mean time of antibiotics was 44.5 months (range 12–162): 13 patients had 24 UTI episodes (0.08 episodes/patient/year), eight (33%) of which were APN (P < 0.05). A renal scan was performed in 71 patients after the index infection and repeated in 12. Two patients lost renal function while still on PA.ConclusionDiscontinuing PA in patients with history of VUR is a safe practice and should be considered as a management option.     

Urinary Tract Infections in Pediatric Oncology Patients with Fever and Neutropenia

The relevancy of the urinary tract as a source of infection during febrile neutropenia is not known. The authors sought to determine the frequency of urinary tract infections (UTIs) in pediatric cancer patients with febrile neutropenia. Urine was collected from a mid-stream void before the administration of antibiotics. Demographic, clinical, and laboratory data were collected. The frequency of UTI and usefulness of urinalysis and localizing signs in predicting UTI in pediatric cancer patients with fever and neutropenia were determined. Forty-five patients had 58 febrile neutropenic episodes eligible for study participation. No patient presented with localizing signs. The urinalysis was negative in 53 episodes and positive in 5 episodes. Four patients had 5 UTIs. The frequency of UTI was 8.6% (5 of 58 febrile neutropenia episodes). Four patients had bacteremia, none of whom had a UTI. The sensitivity, specificity, and negative predictive value of urinalysis was 40%, 94%, and 94%, respectively, and for localizing signs was undefined, 100%, and 91%, respectively. UTI is as common as bacteremia in the current pediatric cancer patients with fever and neutropenia. Urinalysis and urine culture should be obtained routinely as part of the diagnostic evaluation of patients with fever and neutropenia.     

Urinary tract infections in pediatric oncology patients with fever and neutropenia

The relevancy of the urinary tract as a source of infection during febrile neutropenia is not known. The authors sought to determine the frequency of urinary tract infections (UTIs) in pediatric cancer patients with febrile neutropenia. Urine was collected from a mid-stream void before the administration of antibiotics. Demographic, clinical, and laboratory data were collected. The frequency of UTI and usefulness of urinalysis and localizing signs in predicting UTI in pediatric cancer patients with fever and neutropenia were determined. Forty-five patients had 58 febrile neutropenic episodes eligible for study participation. No patient presented with localizing signs. The urinalysis was negative in 53 episodes and positive in 5 episodes. Four patients had 5 UTIs. The frequency of UTI was 8.6% (5 of 58 febrile neutropenia episodes). Four patients had bacteremia, none of whom had a UTI. The sensitivity, specificity, and negative predictive value of urinalysis was 40%, 94%, and 94%, respectively, and for localizing signs was undefined, 100%, and 91%, respectively. UTI is as common as bacteremia in the current pediatric cancer patients with fever and neutropenia. Urinalysis and urine culture should be obtained routinely as part of the diagnostic evaluation of patients with fever and neutropenia.     

Significance of Postnatal Follow-up of Infants with Vesicoureteral Reflux Having Antenatal Hydronephrosis

Objective

To evaluate the frequency of urinary tract infections (UTIs) and degree of renal parenchymal damage as well as the parameters of growth, development and nutritional status in antenatal hydronephrosis cases with vesicoureteral reflux (VUR).

Methods

Infants, whose antenatal ultrasonography (US) showed a fetal renal pelvic diameter of 5 mm or greater were investigated. Of the 277 infants with antenatal HN, 36 [56 renal units (RUs)] were diagnosed with VUR. All cases with VUR were evaluated in terms of the frequency of UTIs, scars appearing on ^99mTechnetium-dimercaptosuccinic acid scan (DMSA), growth and development [height and weight standard deviation scores (HSDS and WSDS)], and nutritional status [relative weight (RW)]. Statistical evaluation was performed using the Chi-squared test.

Findings

Of these 36 patients with VUR, 25 (69.4%) were males and 11 (30.6%) females. Of the 56 RUs, 48 (85.7%) had severe VUR (≥ Grade III). The mean duration of postnatal follow-up was 37.8±24.50 months. The annual UTI frequency was found to be 1.25±0.83 episodes/year. Of these 36 infants, 32 (88.8%) recovered from VUR following either medical (17 patients, 47.2%) or surgical (15 patients, 41.6%) treatment. The initial DMSA showed parenchymal defects in 16 (44.4%) RUs, and 4 RUs showed recovery in the final DMSA. Although statistically insignificant (P>0.05), initial growth and development (HSDS: -0.17±0.86; WSDS: 0.00±0.14) and nutritional status (RW: 98.19±8.81) values gradually improved (0.05±1.06, 0.06±1.071 and 101.97±14.85, respectively).

Conclusion

Postnatal early diagnosis and appropriate management of VUR in infants with antenatal hydronephrosis can prevent the occurrence of frequent UTIs, renal scarring and malnutrition, enabling normal growth and development.     

Is a routine voiding cystourethrogram necessary in children after the first febrile urinary tract infection?

Aim: The aim of this study was to estimate the value of identifying vesicoureteral reflux (VUR) on a voiding cystourethrogram (VCUG) and the benefit of VUR management according to imaging strategies at the first febrile urinary tract infection (UTI). Methods: Children aged 1–144 months (n = 618) with the first febrile UTI admitted at our hospital from 2000 to 2009 were enrolled. In all patients, renal sonogram (US), ^99mTc‐dimercaptosuccinic acid (DMSA) renal scanning and VCUG were performed. Retrospective analyses per patient and per renal unit were performed. Results: Abnormal US or DMSA scans had a sensitivity of 100% and a negative predictive value (NPV) of 100% to detect high‐grade reflux. In hydronephrotic kidneys, DMSA scanning had a sensitivity of 88.2% and a NPV of 97.1% to detect high‐grade reflux. Conclusion: Routine VCUG is not required after the first febrile UTI in patients with normal US or normal DMSA scan. Even if the US reveals hydronephrosis, routine VCUG is not necessary if the DMSA findings are normal. It is recommended that children who did not receive both a DMSA scan and VCUG after the first febrile UTI should be followed up over the long term.     

Non-Escherichia coli versus Escherichia coli community-acquired urinary tract infections in children hospitalized in a tertiary center: relative frequency, risk factors, antimicrobial resistance and outcome

BACKGROUND: Currently hospitalization for children with urinary tract infections (UTIs) is reserved for severe or complicated cases. Changes may have taken place in the characteristics and causative uropathogens of hospital-treated community-acquired UTI. OBJECTIVES: To study children hospitalized in a tertiary center with community-acquired UTI, compare Escherichia coli and non-E. coli UTI, define predictors for non-E. coli UTI and elucidate the appropriate therapeutic approach. PATIENTS AND METHODS: A prospective clinical and laboratory study from 2001 through 2002 in a tertiary pediatric medical center. Patients were divided by results of the urine culture into E. coli and non-E. coli UTI groups, which were compared. RESULTS: Of 175 episodes of culture-proved UTI, 70 (40%) were caused by non-E. coli pathogens. Non-E. coli UTI was more commonly found in children who were male (P = 0.005), who had underlying renal abnormalities (P = 0.0085) and who had received antibiotic therapy in the prior month (P = 0.0009). Non-E. coli uropathogens were often resistant to antibiotics usually recommended for initial therapy for UTI, including cephalosporins and aminoglycosides; 19% were initially treated with inappropriate empiric intravenous antibiotics (compared with 2% for E. coli UTI, P = 0.0001), with a longer hospitalization. CONCLUSIONS: Current treatment routines are often inappropriate for hospitalized children with non-E. coli UTI, which is relatively common in this population. The defined risk factors associated with non-E. coli UTIs and its antimicrobial resistance patterns should be considered to improve empiric antibiotic therapy for these infections.     

99mTc-DMSA scintigraphy in acute urinary tract infection in children

24 children with symptomatic urinary tract infection (UTI) underwent systematically ultrasound studies (US) and^99mTc-DMSA renal scans. Among the 15 patients considered as acute pyelonephritis (APN) on clinical grounds, the scan was abnormal in 12 cases, in contrast with only 1 abnormal scan in the clincial subgroup of the lower UTI. Among the 10 abnormal scans that were repeated later on, 6 did completely normalize. US showed only once a parenchymal appearance suggestive for APN. Our findings suggest that the DMSA scan has to be considered at present as the most sensitive imaging technique for the detection of APN.     

Investigating febrile UTI in infants: Is a cystogram necessary?

ObjectiveCurrent imaging recommendations for investigating any infantile febrile urinary tract infection (UTI) are ultrasound scan (US), micturating cystourethrogram (MCUG) and dimercaptosuccinic acid (DMSA) scan. The aim of this retrospective cohort study was to determine the need and indications for MCUG in the investigation of a first febrile infantile UTI, as doubts have been raised over its benefit.Patients and methodsInformation on 427 infants who had undergone US, MCUG and DMSA following a first febrile UTI was prospectively recorded. The infants were divided into two groups: A (354) with normal renal US and B (73) with abnormal US. DMSA findings were correlated with findings on MCUG. Main outcome measures were incidence of recurrent UTIs, change in management or intervention as a result of MCUG, and outcome at discharge.ResultsOnly 21/354 (6%) infants in Group A had both scarring on DMSA and vesicoureteric reflux (VUR), predominantly low-grade on MCUG. In Group B (abnormal US), 23/73 (32%) had scarring on DMSA and vesicoureteric reflux, predominantly high grade on MCUG. Of the infants with non-scarred kidneys, 73% had dilating reflux. Successful conservative treatment was performed in 423 infants, and 4 infants in Group B required surgery.ConclusionWe recommend US and DMSA in all infantile febrile UTI cases. Where US is normal, MCUG should be reserved for those cases with abnormal DMSA. Where US is abnormal, MCUG should be performed irrespective of findings on DMSA scan. A randomized prospective study is necessary to evaluate this further.     

Urinary tract infections in children with congenital adrenal hyperplasia

OBJECTIVE: To investigate the incidence of urinary tract infections (UTIs) in children with congenital adrenal hyperplasia (CAH), and to determine whether there was a correlation between UTIs and the timing and type of genital surgery in girls. STUDY DESIGN: Medical records of patients with CAH < or = 15 years were reviewed. A parent questionnaire regarding history of UTIs was completed. RESULTS: Seventy-one patients with classic CAH (41 girls, 30 boys) aged 8.3 +/- 4.2 years were identified. Thirty-five (85%) girls had undergone feminizing genitoplasty at 1.1 +/- 0.8 years, while six (15%) had not. History of UTI was reported in nine (12.6%) patients (one boy, eight girls). In seven of the eight girls, genital surgery had been performed and all UTIs occurred after surgery. One UTI was reported in a girl who had not undergone surgery. No correlation was found between UTIs and the type of genital surgery. CONCLUSION: The incidence of UTIs in children with CAH is similar to that in the general population. Although preliminary, our results do not suggest an increased risk of UTIs if surgery is delayed.     

Risk factors in the development of early technetium-99m dimercaptosuccinic acid renal scintigraphy lesions during first urinary tract infection in children

AIM: To establish the variables that correlate with uptake defects in dimercaptosuccinic acid (DMSA) scintigraphy performed in the acute phase of a first episode of urinary tract infection (UTI). METHODS: A prospective observational study was conducted in a cohort of 158 consecutive children with a first episode of symptomatic UTI. The therapeutic delay time (TDT) was recorded. DMSA scintigraphy was performed in all children and voiding cystourethrography in 150 of them. RESULTS: 85% of the patients were younger than 2 y. Mean TDT was 33.5 h. The aetiological agent was Escherichia coli in 140 children. DMSA scintigraphy was normal in 81. Vesicoureteric reflux was detected in 33. After a multivariate logistic regression analysis the following variables were retained in the final model: TDT > or = 48 h, growth of bacteria other than E. coli, percentage of polymorphonuclear cells > or = 60% and C-reactive protein > or = 30 mg l(-1). CONCLUSION: TDT > or = 48 h, bacteria other than E. coli, percentage of polymorphonuclear cells > or = 60% and CRP > or = 30 mg l(-1) influence the findings detected in the DMSA scintigraphy performed in the acute phase of a first episode of UTI.     

The significance of a defect on DMSA scan in children with renal transplants

Since December 1995, pediatric renal transplant recipients in our unit have received a DMSA scan as soon as possible post-transplant in order to provide a baseline for comparison in the event of subsequent complications. We retrospectively reviewed the case notes and DMSA scans of the 45 patients who underwent a scan within 9 wk of their transplant to see if pre or peri-transplant factors or post-transplant complications were associated with defects on scanning. Forty percentage of scans had defects. The presence of defects was not associated with potential predisposing factors such as patient or donor age, cadaveric or live donation, cold ischemia time, multiple donor vessels, the use of non-heart beating donors, the mean time to scan, the serum creatinine, or the presence of structural renal tract anomalies predisposing to UTI. However, 87% of patients had complications before the scan, including UTI, rejection, acute tubular necrosis, transplant biopsy and drug toxicity. Children with no clinical complications had a significantly reduced risk of a defect (p = 0.035), while biopsy was associated with the presence of defects (p = 0.0034). Twenty patients had one or more follow up DMSA scans: one patient developed a new focal defect. In conclusion, renal transplant defects are frequently found on DMSA scanning even early after transplantation and are non-specifically associated with many different complications.     

Antibiotic resistance patterns in children hospitalized for urinary tract infections

BACKGROUND: Children admitted to the hospital with urinary tract infections (UTIs) receive empirical antibiotic therapy. There is limited information on bacterial resistance to commonly prescribed intravenous antibiotics or on the risk factors for increased resistance in these patients. OBJECTIVES: To determine the antibiotic resistance pattern in children admitted to the hospital with UTIs, and to determine if history of UTI, antibiotic prophylaxis, or vesicoureteral reflux increases the risk of resistant organisms. DESIGN/METHODS: We reviewed all of the cases of UTI in children up to 18 years of age who were admitted during a 5-year period to Children's Hospital of Wisconsin, Milwaukee. We recorded age, sex, culture and sensitivity results, imaging that was performed, and past medical history. RESULTS: We identified 361 patients with UTIs. Escherichia coli caused 87% of the infections, although E coli was significantly less common in children receiving prophylactic antibiotics (58%; P<.001) or in children with a history of UTI (74%; P<.001). Resistance to cefotaxime sodium was 3% in the patients not receiving antibiotic prophylaxis, but was 27% in the children receiving prophylactic antibiotics (relative risk, 9.9; 95% confidence interval, 4.0-24.5; P<.001). Resistance to aminoglycoside antibiotics was 1% in the children not receiving prophylaxis and 5% in the children receiving prophylactic antibiotics. CONCLUSIONS: Children who are receiving prophylactic antibiotics and are admitted to the hospital for a UTI are often infected with an organism that is resistant to third-generation cephalosporins. These children are more appropriately treated with an aminoglycoside antibiotic.     

Non‐enhanced magnetic resonance imaging versus renal scintigraphy in acute pyelonephritis

The utility of non‐enhanced magnetic resonance imaging (MRI) has not been examined extensively for diagnosing acute pyelonephritis (APN) in children. The aims of this study were to compare non‐enhanced MRI with technetium‐99 m dimercaptosuccinic acid (^99mTc‐DMSA) renal scintigraphy in detecting APN. Six boys and one girl with temperature ≥38°C and positive urine culture received both non‐enhanced MRI with whole body diffusion‐weighted imaging (DWI) and ^99mTc‐DMSA scintigraphy ≤7 days from the fever onset. The sensitivity and specificity of MRI in detecting APN lesions diagnosed on ^99mTc‐DMSA scintigraphy were 80% and 100%, respectively. Non‐enhanced MRI in children with suspected APN ≤7 days from fever onset might be a suitable replacement for ^99mTc‐DMSA scintigraphy for the detection of APN.     

Risk factors for recurrent urinary tract infection in preschool children

OBJECTIVE: Children with urinary tract infections (UTI) are at risk of renal scarring which may lead to impaired renal function and hypertension. This study examines the risk factors that predispose to recurrent UTI in children and the role of recurrent UTI in renal scarring. METHODOLOGY: A group of 290 children under 5 years of age with a first symptomatic UTI were studied. Micturating cystourethrogram and dimercaptosuccinic acid (DMSA) renal scintigraphy were performed at entry, and DMSA was repeated 1 year later. Two hundred and sixty-one children (90%) were followed up at 1 year. RESULTS: There were 46 confirmed recurrent infections in 34 children, a recurrence rate of 12%. Multiple recurrence occurred in 14/34 (34%) children. Age of less than 6 months on entry independently predicted for recurrent UTI (odds ratio (OR): 2.9)). Compliance with prophylactic antibiotics fell throughout the year of follow up. Vesicoureteric reflux (VUR) was present in 14/34 (34%) of the group with recurrent UTI, 69/256 (27%) without recurrence. Urinary tract infection was significantly associated with bilateral and intrarenal reflux; grade 3-5 reflux independently predicted for recurrent UTI (OR: 3.5). Recurrent UTI was significantly associated with high grade DMSA defects on entry, renal parenchymal defects at 1 year follow up, and new defects at 1 year. CONCLUSION: The independent risk factors for recurrent UTI identified by this study were an age of less than 6 months at the index UTI and grade 3-5 VUR. These findings suggest more selective targeting may minimize problems associated with prophylaxis and improve outcomes for children with urine infection.     

降钙素原对儿童急性肾盂肾炎的诊断价值

目的：探讨降钙素原（PCT）对儿童急性肾盂肾炎（APN）的诊断价值。方法：回顾性分析2011年9月至2012年2月诊断为初发的尿路感染（UTI）且年龄<3岁患儿的病例资料,以核素肾静态扫描（99mTc-DMSA）结果作为诊断APN的金标准,比较上尿路感染（APN）及下尿路感染（非APN）患儿血清PCT、CRP的水平,并绘制二者诊断APN的受试者工作特征曲线（ROC曲线）,判断其诊断性能。结果：共65例UTI患儿纳入研究,其中APN 39例,下尿路感染者26例,前者的血清PCT、CRP水平显著高于后者（分别 3.08 ng/mL vs 0.37 ng/mL;6.25 mg/L vs 3.01 mg/L;均P<0.01）。血清PCT诊断APN的敏感性为84.6%,特异性为88.5%,曲线下面积为0.873（95%可信区间为0.781~0.965）,最佳阈值为1.03 ng/mL;血清CRP诊断APN的敏感性为71.8%,特异性为69.2%,曲线下面积为0.735（95%可信区间为0.612~0.858）,最佳阈值为3.91 mg/L。结论：PCT对儿童APN的诊断具有较高的敏感性及特异性,有助于临床对APN的早期识别。     

Long-term outcome in women who underwent anti-reflux surgery in childhood

BackgroundThe purpose of ureterocystoneostomy to correct vesicoureteral reflux is to thereby prevent recurrent febrile urinary tract infections (UTIs). The objective of this study was to determine the frequency of UTI in adult women who underwent reimplantation as children, with the emphasis on infections during pregnancy.Patients and methodsIncluded in the study were women over 20 years of age who underwent surgery for primary reflux between 1969 and 2004. A total of 392 patients were identified and information on their case history, surgery and follow-up was collected from the medical records. A questionnaire, requesting information on their present state of health, and occurrences of lower or upper UTI since the age of 16 and during any pregnancies, was sent to 337 of these patients.ResultsIn all, 242 (84%) of the questionnaires were returned. UTIs had occurred in 42% of the women before they had any sexual activity; thereafter the frequency increased to 61%. In 113 of the 282 women, 242 pregnancies were recorded. UTI occurred during 59 pregnancies (24%): 19% lower, 5% upper. Risk factors for UTI during pregnancy were infections as adults or decreased differential renal function (≤ 30%).ConclusionsThere is an ongoing risk of UTI in adult women after anti-reflux surgery in childhood. During pregnancy, these women represent a population at risk who should be observed very closely.     

Urinary tract infections in febrile infants younger than 8 weeks of age

In this prospective study of 442 infants younger than 8 weeks of age who attended a pediatric emergency department with temperature greater than or equal to 100.6 degrees F (38.1 degrees C), urinary tract infections (UTIs) were found in 33 patients (7.5%), 2 of whom were bacteremic. Clinical and laboratory data were not helpful for identifying UTIs. Of the 33 patients with UTIs, 32 had urinalyses recorded; 16 were suggestive of a UTI (more than five white blood cells per high-power field or any bacteria present). Of the 16 infants with apparently normal urinalysis results, three had an emergency department diagnosis suggesting an alternative bacterial focus of infection. If the physician had decided on the basis of apparently normal urinalysis results to forgo obtaining a urine culture, more than half of the UTIs would have been missed. Bag-collected specimens were significantly more likely to yield indeterminate urine culture results than either catheter or suprapubic specimens. In addition, uncircumcised males were significantly more likely to have a UTI than circumcised boys. These results suggest that a suprapubic or catheter-obtained urine specimen for culture is a necessary part of the evaluation of all febrile infants younger than 8 weeks of age, regardless of the urinalysis findings or another focus of presumed bacterial infection.     

Neonatal urinary tract infections: Analysis of the patients and recurrences

BACKGROUND: Early diagnosis and proper treatment, including long-term follow up, are very important for neonatal urinary tract infections (UTI). METHODS: The present study reports the analysis and long-term follow-up results of 71 newborns treated for UTI. RESULTS: Forty-one per cent of patients were preterm babies. Suspected sepsis and hyperbilirubinemia were the main presenting features. Community-acquired and nasocomial UTI accounted for 63% and 37% of cases, respectively. The leading causative agents were Escherichia coli for community-acquired UTI and Klebsiella pneumoniae for nasocomial UTI. The urosepsis rate was 5%. Abnormal ultrasonography findings were present in 23% and vesicoureteral reflux was present in 15% of babies. A total of 23% of patients showed renal photopenic areas on dimercaptosuccinic acid scan. The recurrence rate was 28% occurring between 1.5 and 12 months, in particular in the first 6 months. Most of the recurrences developed in patients with no predisposing abnormalities. CONCLUSION: Pediatric nephrologic follow-up of babies experiencing UTI in the neonatal period is very important to identify the predisposing congenital abnormalities and scarred kidneys, to diagnose and to treat the recurrences earlier.