Fever in the clinical diagnosis of acute pyelonephritis

The Problem of Occult Pyelonephritis: Acute Pyelonephritis in Patients Presenting Only with Lower Urinary Tract Symptoms

Pyelonephritis is a prevalent diagnosis of emergency department visits. It commonly presents as flank pain and costovertebral tenderness with urinary symptoms. However, some cases occur without typical symptoms. Our study highlights the dubious presentation of pyelonephritis with lower urinary tract symptoms (LUTS) only. This study was conducted at a tertiary care hospital, where charts and files were reviewed from January 11, 2018 to February 28, 2019 for all the patients with a diagnosis of acute pyelonephritis from medical records. In our study, 521 patients were included and 492 (94%) of the participants were suffering from pyelonephritis. Approximately 22.8% of the patients showed the absence of both flank pain and costovertebral tenderness but were diagnosed with pyelonephritis based on computed tomography (CT) and magnetic resonance imaging (MRI). Moreover, 27% of the patients reported upper urinary tract symptoms only and were diagnosed by CT or MRI findings. Out of that only 24% and 16% of the patients reported flank pain and costovertebral tenderness, respectively. Insignificant associations with pyelonephritis were found for age, gender and other comorbidities. Our study showed a significant number of patients with pyelonephritis without any upper urinary tract symptoms. Patients with LUTS should be evaluated further by imaging if they belong to the high-risk population.

Delayed Fever and Acute Kidney Injury in Patients with Urinary Tract Infection

The presence of fever has long been a warning sign of severe urinary tract infection (UTI). However, we previously identified that inpatients with afebrile UTI had an increased risk of developing acute kidney injury (AKI). After expanding this cohort, 1132 inpatients with UTI diagnosed between January 2006 and April 2019 were analyzed. Overall, 159 (14%) of these patients developed AKI; bacteremia, urolithiasis, septic shock, hypertension, lower baseline renal function, marked leukocytosis, and the absence of fever were independently linked to AKI. When we further studied the cohort of inpatients with fever during hospitalization, we identified a group of "delayed fever" UTI inpatients who did not have fever as their initial presentation. Compared to patients presenting with fever at the emergency department, patients with delayed fever tended to be younger and have less frequent infection with Escherichia coli, more frequent AKI, upper tract infection, and a longer hospital stay. Despite the initial absence of fever, these patients demonstrated larger extents of elevations in both serum white blood cell counts and C-reactive protein levels. In short, besides UTI patients with lower baseline renal function that remain afebrile during their hospital stay, clinical awareness of the increased incidence of AKI in younger patients with "delayed fever" should also be noted.

Activate: Randomized Clinical Trial of BCG Vaccination against Infection in the Elderly

BCG vaccination in children protects against heterologous infections and improves survival independently of tuberculosis prevention. The phase III ACTIVATE trial assessed whether BCG has similar effects in the elderly. In this double-blind, randomized trial, elderly patients (n = 198) received BCG or placebo vaccine at hospital discharge and were followed for 12 months for new infections. At interim analysis, BCG vaccination significantly increased the time to first infection (median 16 weeks compared to 11 weeks after placebo). The incidence of new infections was 42.3% (95% CIs 31.9%–53.4%) after placebo vaccination and 25.0% (95% CIs 16.4%–36.1%) after BCG vaccination; most of the protection was against respiratory tract infections of probable viral origin (hazard ratio 0.21, p = 0.013). No difference in the frequency of adverse effects was found. Data show that BCG vaccination is safe and can protect the elderly against infections. Larger studies are needed to assess protection against respiratory infections, including COVID-19 (ClinicalTrials.gov NCT03296423).

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ACTIVATE is a prospective randomized trial of BCG vaccination in the elderly

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BCG increased the time to first infection and decreased the incidence of new infection

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Strongest protection was found against viral respiratory tract infections

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Epigenetic reprogramming and increased cytokine production was found in monocytes

The neutrophil-to-lymphocyte ratio is associated with bacteremia in older adults visiting the emergency department with urinary tract infections

PURPOSE

We evaluated the clinical features of older adults visiting the emergency department (ED) with urinary tract infections (UTIs), and the diagnostic utility of the neutrophil-to-lymphocyte ratio (NLR) in terms of identifying bacteremia.

METHODS

In total, 479 older adults admitted with UTIs via the ED between January 2010 and December 2015 were retrospectively reviewed. We recorded age, sex, comorbidities, body temperature, clinical findings, and initial laboratory results, including the NLR.

RESULTS

A UTI with bacteremia was identified in 186 (38.8%) older adults. Bacteremia was associated with a longer hospital stay (median 10 vs. 8 days, p < 0.001). NLRs and C-reactive protein, blood urea nitrogen and creatinine levels were significantly higher in the bacteremia group than in the non-bacteremia group (p < 0.001, p = 0.016, p = 0.008, and p = 0.011, respectively). The area under the curve for the NLR was 0.624 (95% CI = 0.579-0.668, p < 0.001), and the cutoff was 9.0 (sensitivity 74.2, specificity 49.2%). Independent risk factors for bacteremia were an NLR ≥ 9 and fever ≥ 39 °C (OR 2.43, OR 2.75: p < 0.001, p < 0.001, respectively).

CONCLUSION

Bacteremia was associated with a longer hospital stay in older adults with UTIs, in whom the initial NLR and high fever reliably predicted bacteremia. The NLR may help emergency physicians to predict bacteremia in older adults with UTIs visiting the ED.

Pyelonephritis in Pregnancy: Relationship of Fever and Maternal Morbidity

Objective  To evaluate the relationship between maternal fever at the time of hospital admission and subsequent maternal morbidity in pregnant patients with pyelonephritis. Study Design  In this retrospective cohort study, inpatient records were reviewed for all obstetric patients discharged from a single tertiary care hospital between June 1, 2011, and May 30, 2017, with the diagnosis of pyelonephritis. Patients were stratified into two groups, those with and without fever at the time of admission. Descriptive statistics were utilized to evaluate the association of fever at the time of presentation with subsequent morbidity. Using admission vital signs, maternal early warning criteria (MEWC) were applied and odds ratios calculated to predict intensive care unit (ICU) admission. Results  A total of 110 patients were admitted with pyelonephritis in pregnancy; 24 patients were febrile and 86 patients were afebrile on admission. There was no difference in rates of maternal ICU admission between both groups. Positive MEWC was predictive of ICU admission with an adjusted odds ratio of 16.54 (95% confidence interval: 1.29-212.5; p  = 0.03). Conclusion  Afebrile pregnant patients with pyelonephritis remain at risk of significant maternal morbidity. Application of the MEWC on admission identifies patients at higher risk of ICU admission.

Urinary tract infections in patients with neurogenic bladder

Urinary tract infections (UTIs) in patients with neurogenic bladder are a major public health issue due to their high incidence and major consequences. Despite their frequency and potential severity, their physiopathology and management are poorly known. We provide a narrative literature review on the epidemiology, physiopathology, diagnostic criteria, microbiology, antimicrobial management, and prevention. UTIs among patients with neurogenic bladder are associated with high morbidity and healthcare utilization. Risk factors for UTI among this population are: indwelling catheter, urinary stasis, high bladder pressure, and bladder stones. Their diagnosis is a major challenge as clinical signs are often non-specific and rare. A urinary sample should be analyzed in appropriate conditions before any antibiotic prescription. According to most guidelines, a bacterial threshold≥103CFU/ml associated with symptoms is acceptable to define UTI in patients with neurogenic bladder. The management of acute symptomatic UTI is not evidence-based. A management with a single agent and a short antibiotic treatment of 10 days or less seems effective. Antibiotic selection should be based on the patient's resistance patterns. Asymptomatic bacteriuria should not be treated to avoid the emergence of bacterial resistance. Regarding preventive measures, use of clean intermittent catheterization, intravesical botulinum toxin injection, and prevention using antibiotic cycling are effective. Bacterial interference is promising but randomized controlled trials are needed. Large ongoing cohorts and randomized controlled trials should soon provide more evidence-based data.

The Emergency Department Diagnosis and Management of Urinary Tract Infection

Urinary tract infection (UTI) is a common infection seen in the emergency department. The spectrum of UTI includes simple versus complicated infection and lower versus upper UTI. No one history or examination finding is definitive for diagnosis. Testing often includes urinalysis and/or urine dipstick, and several pitfalls may occur in interpretation. Urine cultures should be obtained in complicated or upper UTIs but not simple and lower tract UTIs, unless a patient is pregnant. Imaging often is not required. Most patients with simple cystitis and pyelonephritis are treated as outpatients. A variety of potentially dangerous conditions may mimic UTI and pyelonephritis.

The procalcitonin/albumin ratio as an early diagnostic predictor in discriminating urosepsis from patients with febrile urinary tract infection

Discrimination between urosepsis and febrile urinary tract infections is important in therapeutic decision-making to indicate suitable treatments to avoid sepsis-related organ failure. Accurate diagnosis is time-consuming and susceptible to false-positive results. Moreover, patient responses to urosepsis are complex and varied. Therefore, this study aimed to develop a new, early diagnostic predictor that could discriminate between patients with urosepsis and those with febrile urinary tract infections using a combination of initial procalcitonin and albumin levels.We conducted a retrospective study involving 140 patients with febrile urinary tract infections from January 2013 to December 2017. Univariate and multivariate logistic analyses were performed to identify the independent risk factors for differentiating urosepsis from febrile urinary tract infection. A receiver operating characteristic (ROC) curve analysis was conducted to compare the predictive accuracy of the procalcitonin/albumin ratio.Patients in the urosepsis group had higher procalcitonin/albumin ratios compared to those in the febrile urinary tract infection group [2.254 (0.978, 6.299) vs 0.021 (0.004, 0.095); P < .001]. Based on multivariate logistic analysis, the procalcitonin/albumin ratio [adjusted odds ratio (OR) 1.029, 95% confidence interval (CI) 1.013-1.045, P < .001] was an independent predictor of urosepsis, which allowed for differentiation from patients with febrile urinary tract infections. The area under the ROC curve (AUC) for the procalcitonin/albumin ratio was 0.937 (95% CI, 0.894-0.980); P < .001. The sensitivity and specificity of the procalcitonin/albumin ratio cut-off values (>0.44) were 84.62% and 96.00%, respectively. Moreover, in the subset of 65 patients with urosepsis, the procalcitonin/albumin ratio in the uroseptic shock group was higher than in the group of patients without uroseptic shock [5.46 (1.43, 6.58) vs 1.24 (0.63, 4.38); P = .009].Our study demonstrates that the procalcitonin/albumin ratio is an early diagnostic predictor that can discriminate between urosepsis and febrile urinary tract infection. Additionally, in patients with urosepsis, those with higher procalcitonin/albumin ratios were more prone to uroseptic shock. Our findings suggest that the procalcitonin/albumin ratio is a rapid and relatively low-cost biomarker that can be used in clinical practice.

Enhancing quality practice for prevention and diagnosis of urinary tract infection during inpatient spinal cord rehabilitation

OBJECTIVES

To reduce the incidence of Urinary Tract Infection (UTI) in subacute SCI individuals admitted for tertiary inpatient rehabilitation.

DESIGN

A quality improvement team was assembled to improve UTI prevention/diagnosis. To plan data collection, UTI-related factors were mapped in an Ishikawa (fishbone) driver diagram. Data including patient demographics, presence and frequency of signs and/or symptoms of UTI and antibiotic initiation from August to December 2015 were recorded. Sensitivity, Specificity, Positive and Negative Predictive Values (PPV, NPV), and Likelihood Ratios (LR) were calculated for each sign and symptom.

SETTING

Tertiary SCI Rehabilitation Results: Among 55 inpatients with subacute SCI who had signs/symptoms prompting urine culture and sensitivity (C&S), 32 (58.18%) were diagnosed with a UTI. The most frequent symptoms were foul smelling urine (41%), change in urine color (31%), and incontinence (25%), and the most common sign was fever (34%). Most UTIs (81%) occurred among individuals using Clean Intermittent Catheterization (CIC), with 46% of catheterizations performed by nurses. Foul smelling urine had the highest sensitivity (0.50, 95% CI: 0.31-0.69), and new incontinence had the highest specificity (0.88, 95% CI: 0.69-0.97) for UTI diagnosis. The highest PPV belonged to the cloudy urine (0.71, 95% CI: 0.42-0.92). The combination of cloudy and foul smelling urine increased the PPV to 78% (95% CI: (0.40-0.97).

CONCLUSIONS

The concurrent presence of cloudy and foul smelling urine is predicted of UTI diagnosis inpatients tertiary setting. SCI inpatients are susceptible to UTI when learning CIC technique from nurses.

Randomized, controlled, multicentre clinical trial of the antipyretic effect of intravenous paracetamol in patients admitted to hospital with infection

Aim

No randomized study has been conducted to investigate the use of intravenous paracetamol (acetaminophen, APAP) for the management of fever due to infection. The present study evaluated a new ready‐made infusion of paracetamol.

Methods

Eighty patients with a body temperature onset ≥38.5°C in the previous 24 h due to infection were randomized to a single administration of placebo (n = 39) or 1 g paracetamol (n = 41), and their temperature was recorded at standard intervals. Rescue medication with 1 g paracetamol was allowed. Serum samples were collected for the measurement of APAP and its metabolites. The primary endpoint was defervescence, defined as a core temperature ≤37.1°C.

Results

During the first 6 h, defervescence was achieved in 15 (38.5%) patients treated with placebo compared with 33 (80.5%) patients treated with paracetamol 1 g (P < 0.0001). The median time to defervescence with paracetamol 1 g was 3 h. Rescue medication was given to 15 (38.5%) and five (12.2%) patients allocated to placebo and paracetamol, respectively (P = 0.007); nine (60.0%) and two (40.0%) of these patients, respectively, experienced defervescence. No further antipyretic medication was needed for patients becoming afebrile with rescue medication. Serum glucuronide‐APAP concentrations were significantly greater in the serum of patients who did not experience defervescence with paracetamol. The efficacy of paracetamol was not affected by serum creatinine. No drug‐related adverse events were reported.

Conclusions

The 1 g paracetamol formulation has a rapid and sustainable antipyretic effect on fever due to infection. Its efficacy is dependent on hepatic metabolism.

Approach to Pediatric Patients with UTI in the PICU

Urosepsis and UTI are common causes and comorbidities in children admitted to the pediatric intensive care unit (PICU). Risk factors for morbidity and mortality in pediatric patients include young age (< 2 years old), presence of congenital renal anomalies of the urinary tract, and immunosuppression from transplant (kidney, liver, heart, and bone marrow). Workup of urosepsis focuses on identification of renal anomalies of the urinary tract through ultrasound, X-ray cystourethrogram, urodynamic studies, and CT/MRI. Management consists of appropriate choice in antibiotics, hemodynamic instability, and prevention of acute kidney injury (AKI) with particular recognition that chronic renal failure can be present in all chronically ill children, which is not limited to pediatric patients with congenital anomalies of the kidney urinary tract. This review includes a review of the workup and management of pediatric patients with UTI and urosepsis in both healthy patients and patients with known anomalies of the urinary tract.

Management of febrile urinary tract infection among spinal cord injured patients

BACKGROUND

Urinary tract infection (UTI) among patients with neurogenic bladder is a major problem but its management is not well known. We studied the relationship between antibiotic regimen use and the cure rate of those infections among 112 patients with neurogenic bladder.

METHODS

We studied a retrospective cohort of febrile UTI among patients with neurogenic bladder. Drug selection was left to the discretion of the treating physicians, in accordance with current guidelines. Patients were divided into 3 groups according to antibiotic treatment duration (<10 days, between 10 and 15 days, and >15 days). We analysed clinical and microbiogical cure rate one month after the end of antibiotic treatment.

RESULTS

The three groups of patients were similar, especially in terms of drug treatment (equal distribution). The cure rates were not significantly different (71.4 %, 54.2 %, and 57.1 %, respectively; p = 0.34). Moreover, there was no difference in cure rate between mono and dual therapy (44 % for monotherapy vs. 40 % for dual therapy; p = 0.71).

CONCLUSION

This descriptive study supports the efficacy of antimicrobial treatment duration of less than 10 days and the use of monotherapy to treat febrile UTI among patients with neurogenic bladder. A randomized control trial is required to confirm these data.

Individualized significance of the -251 A/T single nucleotide polymorphism of interleukin-8 in severe infections

Based on the concept of the individualized nature of sepsis, we investigated the significance of the -251 A/T (rs4073) single nucleotide polymorphism (SNP) of interleukin (IL)-8 in relation to the underlying infection. Genotyping was performed in 479 patients with severe acute pyelonephritis (UTI, n = 146), community-acquired pneumonia (CAP, n = 109), intra-abdominal infections (IAI, n = 119), and primary bacteremia (BSI, n = 105) by restriction fragment length polymorphism of the polymerase chain reaction (PCR) product and compared with 104 healthy volunteers. Circulating IL-8 was measured within the first 24 h of diagnosis by an immunosorbent assay. Carriage of the AA genotype was protective from the development of UTI (odds ratio 0.38, p: 0.007) and CAP (odds ratio 0.30, p: 0.004), but not from IAI and BSI. Protection from the development of severe sepsis/septic shock was provided for carriers of the AA genotype among patients with UTI (odds ratio 0.15, p: 0.015). This was accompanied by greater concentrations of circulating IL-8 among patients with the AA genotype. It is concluded that carriage of rs4073 modifies susceptibility for severe infection in an individualized way. This is associated with a modulation of circulating IL-8.

Angiopoietin-2 associations with the underlying infection and sepsis severity

Angiopoietin-2 (Ang-2) is an important mediator in sepsis. We have previously shown that endotoxemia levels are related to the underlying infection and affect septic patients' outcome. Based on this background we now investigated if circulating Ang-2 (cAng-2) and monocyte Ang-2 expression in septic patients are associated with the underlying infection and organ failure. We measured cAng-2 in 288 septic patients (121 with sepsis, 167 with severe sepsis/septic shock) at less than 24h post study inclusion (day 1) and on days 3 and 7. Peripheral blood mononuclear cells (PBMCs) were additionally isolated; Ang-2 gene expression was estimated by means of real-time PCR. Levels of cAng-2 were higher under severe sepsis and septic shock, as compared to uncomplicated sepsis; PBMC Ang-2 copies were higher in severe sepsis. On day 1, cAng-2 and Ang-2 gene copies were greater under severe sepsis/septic shock in sufferers from all types of infections with the exception of community-acquired pneumonia and ventilator-associated pneumonia. cAng-2 increased proportionally to the number of failing organs, and was higher under metabolic acidosis and acute coagulopathy as compared to no failing organ. On day 1, copies of Ang-2 were higher in survivors, whereas cAng-2 was higher in non-survivors. In a large cohort of septic patients, cAng-2 kinetics appears associated with the underlying infection and organ failure type.

Exploratory analysis of urinary tract infection using a GC-APCI-MS platform

This study shows the first application of GC-APCI-MS in a clinical setting specifically in the context of urinary tract infection.

Early changes of the kinetics of monocyte trem-1 reflect final outcome in human sepsis

Background

TREM-1 (triggering receptor expressed on myeloid cells), a receptor expressed on neutrophils and monocytes, is upregulated in sepsis and seems to tune the inflammatory response. We explored the expression of TREM-1 at the gene level and on cell membranes of monocytes and association with clinical outcome.

Methods

Peripheral venous blood was sampled from 75 septic patients (39 patients with sepsis, 25 with severe sepsis and 11 with septic shock) on sepsis days 1, 3 and 7. TREM-1 on monocytes was measured by flow cytometry; gene expression of TREM-1 in circulating mononuclear cells was assessed by real-time PCR. sTREM-1 was measured in serum by an enzyme immunoassay.

Results

Although surface TREM-1, sTREM-1 and TREM-1 gene expression did not differ between sepsis, severe sepsis and septic shock on day 1, survivors had greater expression of surface TREM-1 on days 3 and 7 compared to non-survivors. sTREM-1 on non-survivors decreased on day 3 compared to baseline. Patients with increase of monocyte gene expression of TREM-1 from day 1 to day 3 had prolonged survival compared to patients with decrease of gene expression of TREM-1 from day 1 to day 3 (p: 0.031).

Conclusions

Early decrease of gene expression of TREM-1 in monocytes is associated with poor outcome. A reciprocal decrease of the pro-inflammatory surface receptor TREM-1 linked with sepsis-induced immunosuppression may be part of the explanation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12865-014-0063-y) contains supplementary material, which is available to authorized users.

Bloodstream infections and sepsis in Greece: over-time change of epidemiology and impact of de-escalation on final outcome

BACKGROUND

Choice of empirically prescribed antimicrobials for sepsis management depends on epidemiological factors. The epidemiology of sepsis in Greece was studied in two large-periods.

METHODS

Sepsis due to bloodstream infections (BSI) from July 2006 until March 2013 was recorded in a multicenter study in 46 departments. Patients were divided into sepsis admitted in the emergencies and hospitalized in the general ward (GW) and sepsis developing after admission in the Intensive Care Unit (ICU). The primary endpoints were the changes of epidemiology and the factors related with BSIs by multidrug-resistant (MDR) pathogens; the secondary endpoint was the impact of de-escalation on antimicrobial therapy.

RESULTS

754 patients were studied; 378 from 2006-2009 and 376 from 2010-2013. Major differences were recorded between periods in the GW. They involved increase of: sepsis severity; the incidence of underlying diseases; the incidence of polymicrobial infections; the emergence of Klebsiella pneumoniae as a pathogen; and mortality. Factors independently related with BSI by MDR pathogens were chronic hemofiltration, intake of antibiotics the last three months and residence into long-term care facilities. De-escalation in BSIs by fully susceptible Gram-negatives did not affect final outcome. Similar epidemiological differences were not found in the ICU; MDR Gram-negatives predominated in both periods.

CONCLUSIONS

The epidemiology of sepsis in Greece differs in the GW and in the ICU. De-escalation in the GW is a safe strategy.

Predictive factors of bacteremia in patients with febrile urinary tract infection: an experience at a tertiary care center

PURPOSE

To investigate the clinical features in adult patients with febrile urinary tract infection (UTI) who visited the emergency department (ED) and to determine the predictive factors of bacteremia among the initial presenting clinical features.

METHODS

This retrospective cohort study was conducted at the ED of a tertiary hospital in Korea from 1 January 2012 to 31 December 2012. All adult patients who were diagnosed with febrile UTI and for whom data on blood and urine cultures were available were included in the study. Clinical examinations and laboratory tests were performed at the initial presentation.

RESULTS

A total of the 325 patients with febrile UTI (median age: 60 years) were included for analysis, of whom 82 % were female. Bacteremia was detected in 106 of the 325 patients (32.6 %), with Escherichia coli the most frequent pathogen detected (59.7 % of cases). Between the bacteremic and non-bacteremic groups, there was significant difference in age (67 vs. 57 years, respectively), flank pain (16 vs. 7.8 %), suprapubic discomfort (0 vs. 4.6 %), body temperature (38.8 vs. 38.3 °C), respiratory rate (21 vs. 20/min), platelet count (170 vs. 186 × 10(3)/μL), C-reactive protein (10.2 vs. 8.3 mg/dL), and procalcitonin (1.5 vs. 0.3 ng/mL) (P < 0.05 for all). In the multivariate logistic regression analysis, age [odds ratio (OR) 1.03; 95 % confidence interval (CI) 1.01-1.05], systolic blood pressure of <90 mmHg (OR 3.27; 95 % CI 1.13-9.45), body temperature of >39 °C (OR 4.26; 95 % CI 2.28-7.96), and procalcitonin level of >0.5 ng/dL (OR 2.03; 95 % CI 1.07-3.86) were significantly associated with bacteremia.

CONCLUSION

Among our adult patients with febrile UTI, age, systolic blood pressure, body temperature, and procalcitonin were significantly associated with bacteremia. We therefore suggest that these factors should be considered when deciding upon treatment options for febrile UTI patients at the ED.

The role of procalcitonin and IL-6 in discriminating between septic and non-septic causes of ALI/ARDS: a prospective observational study

BACKGROUND

The aim was to evaluate the clinical usefulness of a single plasma and bronchoalveolar lavage fluid (BALF) PCT and IL-6 measurement in discriminating septic from non-septic causes of acute respiratory distress syndrome (ARDS) and forecasting clinical outcomes.

METHODS

One hundred patients were enrolled within 48 h of ALI/ARDS recognition. Demographic, clinical data, severity indices were recorded and PCT and IL-6 concentrations were measured in plasma and BALF.

RESULTS

Plasma PCT and IL-6 values were significantly higher in septic compared to non-septic individuals (p=0.001 and 0.0005, respectively), while there were no differences in their respective BALF values. As far as identification of septic vs. non-septic ARDS is concerned, the comparison of the areas under the curves favored PCT vs. IL-6 [0.88, (95% CI 0.81-0.95) vs. 0.71, (95% CI 0.60-0.81); χ(2)=9.04, p=0.003]. A plasma PCT level of 0.815 ng/mL was associated with 74.1% sensitivity and 97.6% specificity in identifying septic ARDS cases; this corresponded to a diagnostic odds ratio value of 116. Linear regression multivariable analysis disclosed a significant relation of plasma PCT with SOFA score in septic ARDS patients (p<0.001), while neither BALF PCT nor IL-6 levels were associated with clinical outcome.

CONCLUSIONS

Early plasma - but not BALF - PCT concentrations can discriminate between septic and non-septic ARDS causes and are associated with the severity of multiple organ dysfunction syndrome in septic ARDS patients. However, neither plasma or BALF IL-6 levels nor BALF PCT levels carry any prognostic potential. A single plasma PCT value higher than 0.815 ng/mL makes a non-septic cause of ARDS highly unlikely.

Kinetics of circulating immunoglobulin M in sepsis: relationship with final outcome

Introduction

The aim of this study was to investigate the kinetics of immunoglobulin M (IgM) during the different stages of sepsis.

Methods

In this prospective multicenter study, blood sampling for IgM measurement was done within the first 24 hours from diagnosis in 332 critically ill patients; in 83 patients this was repeated upon progression to more severe stages. Among these 83 patients, 30 patients with severe sepsis progressed into shock and IgM was monitored daily for seven consecutive days. Peripheral blood mononuclear cells (PBMCs) were isolated from 55 patients and stimulated for IgM production.

Results

Serum IgM was decreased in septic shock compared to patients with systemic inflammatory response syndrome (SIRS) and patients with severe sepsis. Paired comparisons at distinct time points of the sepsis course showed that IgM was decreased only when patients deteriorated from severe sepsis to septic shock. Serial measurements in these patients, beginning from the early start of vasopressors, showed that the distribution of IgM over time was significantly greater for survivors than for non-survivors. Production of IgM by PBMCs was significantly lower at all stages of sepsis compared with healthy controls.

Conclusions

Specific changes of circulating IgM occur when patients with severe sepsis progress into septic shock. The distribution of IgM is lower among non-survivors.

Polymicrobial bloodstream infections: Epidemiology and impact on mortality

The aim of this study was to investigate the impact of polymicrobial bloodstream infections (pBSIs) on the outcome of sepsis in an area where antimicrobial resistance is of concern. This was a retrospective analysis of data collected prospectively from patients developing BSI outside of an intensive care unit (non-ICU patients) or after ICU admission. Demographics and clinical characteristics were compared for patients with pBSI versus monomicrobial BSI (mBSI) and following stratification by ICU or non-ICU and severity of sepsis status. Possible risk factors for adverse outcome were explored by multivariate analysis, and outcomes were measured by Cox regression analysis. Among 412 patients with BSI, 47 patients (11.4%) with pBSI were recorded; compared with patients with mBSI, they had significantly higher APACHE II scores and presented more frequently with severe sepsis/septic shock. The all-cause 28-day mortality was significantly higher for pBSI versus mBSI (38.3% vs. 24.7%; P=0.033), whereas appropriateness of treatment was comparable (78.7% vs. 86.6%). Primary bacteraemia by combinations of Enterococcus faecalis, Klebsiella pneumoniae and Acinetobacter baumannii was predominant among pBSIs; in mBSIs, urinary tract infections by Escherichia coli, K. pneumoniae or Pseudomonas aeruginosa predominated. Multivariate analysis demonstrated pBSI as a significant contributor to 28-day mortality (HR=1.86; P=0.039), along with presence of two or more co-morbidities (HR=2.35; P=0.004). In conclusion, pBSIs differed epidemiologically from mBSIs, with the emergence of enterococcal species, and portended an almost two-fold increased risk of 28-day mortality. Prospective studies are warranted to elucidate possibly modifiable factors.

Intra-abdominal and pelvic emergencies

The diversity in intra-abdominal/pelvic infections is more than any other organ system. Several clinical scenarios can end up in intra-abdominal infections. The common causes include penetrating abdominal trauma, abdominal surgery, diverticulitis, appendicitis, pancreatitis, biliary disease, perforated viscus, and primary peritonitis. Intra-abdominal infections can masquerade as fever of obscure origin or as dysfunction of neighboring organs, such as lower lobe pneumonia related to a subphrenic abscess or an abscess causing small bowel obstruction. An urgent surgical intervention is the mainstay of the management of serious intra-abdominal infections.

Risk assessment in sepsis: a new prognostication rule by APACHE II score and serum soluble urokinase plasminogen activator receptor

INTRODUCTION

Early risk assessment is the mainstay of management of patients with sepsis. APACHE II is the gold standard prognostic stratification system. A prediction rule that aimed to improve prognostication by APACHE II with the application of serum suPAR (soluble urokinase plasminogen activator receptor) is developed.

METHODS

A prospective study cohort enrolled 1914 patients with sepsis including 62.2% with sepsis and 37.8% with severe sepsis/septic shock. Serum suPAR was measured in samples drawn after diagnosis by an enzyme-immunoabsorbent assay; in 367 patients sequential measurements were performed. After ROC analysis and multivariate logistic regression analysis a prediction rule for risk was developed. The rule was validated in a double-blind fashion by an independent confirmation cohort of 196 sepsis patients, predominantly severe sepsis/septic shock patients, from Sweden.

RESULTS

Serum suPAR remained stable within survivors and non-survivors for 10 days. Regression analysis showed that APACHE II ≥ 17 and suPAR ≥ 12 ng/ml were independently associated with unfavorable outcome. Four strata of risk were identified: i) APACHE II <17 and suPAR <12 ng/ml with mortality 5.5%; ii) APACHE II < 17 and suPAR ≥ 12 ng/ml with mortality 17.4%; iii) APACHE II ≥ 17 and suPAR <12 ng/ml with mortality 37.4%; and iv) APACHE II ≥ 17 and suPAR ≥ 12 ng/ml with mortality 51.7%. This prediction rule was confirmed by the Swedish cohort.

CONCLUSIONS

A novel prediction rule with four levels of risk in sepsis based on APACHE II score and serum suPAR is proposed. Prognostication by this rule is confirmed by an independent cohort.

TREM-1 expression on neutrophils and monocytes of septic patients: relation to the underlying infection and the implicated pathogen

BACKGROUND

Current knowledge on the exact ligand causing expression of TREM-1 on neutrophils and monocytes is limited. The present study aimed at the role of underlying infection and of the causative pathogen in the expression of TREM-1 in sepsis.

METHODS

Peripheral venous blood was sampled from 125 patients with sepsis and 88 with severe sepsis/septic shock. The causative pathogen was isolated in 91 patients. Patients were suffering from acute pyelonephritis, community-acquired pneumonia (CAP), intra-abdominal infections (IAIs), primary bacteremia and ventilator-associated pneumonia or hospital-acquired pneumonia (VAP/HAP). Blood monocytes and neutrophils were isolated. Flow cytometry was used to estimate the TREM-1 expression from septic patients.

RESULTS

Within patients bearing intrabdominal infections, expression of TREM-1 was significantly lower on neutrophils and on monocytes at severe sepsis/shock than at sepsis. That was also the case for severe sepsis/shock developed in the field of VAP/HAP. Among patients who suffered infections by Gram-negative community-acquired pathogens or among patients who suffered polymicrobial infections, expression of TREM-1 on monocytes was significantly lower at the stage of severe sepsis/shock than at the stage of sepsis.

CONCLUSIONS

Decrease of the expression of TREM-1 on the membrane of monocytes and neutrophils upon transition from sepsis to severe sepsis/septic shock depends on the underlying type of infection and the causative pathogen.

Inhibition of caspase-1 activation in Gram-negative sepsis and experimental endotoxemia

Introduction

Down-regulation of ex-vivo cytokine production is a specific feature in patients with sepsis. Cytokine downregulation was studied focusing on caspase-1 activation and conversion of pro-interleukin-1β into interleukin-1β (IL-1β).

Methods

Peripheral blood mononuclear cells were isolated from a) 92 patients with sepsis mainly of Gram-negative etiology; b) 34 healthy volunteers; and c) 5 healthy individuals enrolled in an experimental endotoxemia study. Cytokine stimulation was assessed in vitro after stimulation with a variety of microbial stimuli.

Results

Inhibition of IL-1β in sepsis was more profound than tumour necrosis factor (TNF). Down-regulation of IL-1β response could not be entirely explained by the moderate inhibition of transcription. We investigated inflammasome activation and found that in patients with sepsis, both pro-caspase-1 and activated caspase-1 were markedly decreased. Blocking caspase-1 inhibited the release of IL-1β in healthy volunteers, an effect that was lost in septic patients. Finally, urate crystals, which specifically induce the NLPR3 inflammasome activation, induced significant IL-1β production in healthy controls but not in patients with sepsis. These findings were complemented by inhibition of caspase-1 autocleavage as early as two hours after lipopolysaccharide exposure in volunteers.

Conclusions

These data demonstrate that the inhibition of caspase-1 and defective IL-1 β production is an important immunological feature in sepsis.

Procalcitonin reflects bacteremia and bacterial load in urosepsis syndrome: a prospective observational study

INTRODUCTION

Guidelines recommend that two blood cultures be performed in patients with febrile urinary tract infection (UTI), to detect bacteremia and help diagnose urosepsis. The usefulness and cost-effectiveness of this practice have been criticized. This study aimed to evaluate clinical characteristics and the biomarker procalcitonin (PCT) as an aid in predicting bacteremia.

METHODS

A prospective observational multicenter cohort study included consecutive adults with febrile UTI in 35 primary care units and 8 emergency departments of 7 regional hospitals. Clinical and microbiological data were collected and PCT and time to positivity (TTP) of blood culture were measured.

RESULTS

Of 581 evaluable patients, 136 (23%) had bacteremia. The median age was 66 years (interquartile range 46 to 78 years) and 219 (38%) were male. We evaluated three different models: a clinical model including seven bed-side characteristics, the clinical model plus PCT, and a PCT only model. The diagnostic abilities of these models as reflected by area under the curve of the receiver operating characteristic were 0.71 (95% confidence interval (CI): 0.66 to 0.76), 0.79 (95% CI: 0.75 to 0.83) and 0.73 (95% CI: 0.68 to 0.77) respectively. Calculating corresponding sensitivity and specificity for the presence of bacteremia after each step of adding a significant predictor in the model yielded that the PCT > 0.25 μg/l only model had the best diagnostic performance (sensitivity 0.95; 95% CI: 0.89 to 0.98, specificity 0.50; 95% CI: 0.46 to 0.55). Using PCT as a single decision tool, this would result in 40% fewer blood cultures being taken, while still identifying 94 to 99% of patients with bacteremia.The TTP of E. coli positive blood cultures was linearly correlated with the PCT log value; the higher the PCT the shorter the TTP (R(2) = 0.278, P = 0.007).

CONCLUSIONS

PCT accurately predicts the presence of bacteremia and bacterial load in patients with febrile UTI. This may be a helpful biomarker to limit use of blood culture resources.

Procalcitonin reflects bacteremia and bacterial load in urosepsis syndrome: a prospective observational study

INTRODUCTION

Guidelines recommend that two blood cultures be performed in patients with febrile urinary tract infection (UTI), to detect bacteremia and help diagnose urosepsis. The usefulness and cost-effectiveness of this practice have been criticized. This study aimed to evaluate clinical characteristics and the biomarker procalcitonin (PCT) as an aid in predicting bacteremia.

METHODS

A prospective observational multicenter cohort study included consecutive adults with febrile UTI in 35 primary care units and 8 emergency departments of 7 regional hospitals. Clinical and microbiological data were collected and PCT and time to positivity (TTP) of blood culture were measured.

RESULTS

Of 581 evaluable patients, 136 (23%) had bacteremia. The median age was 66 years (interquartile range 46 to 78 years) and 219 (38%) were male. We evaluated three different models: a clinical model including seven bed-side characteristics, the clinical model plus PCT, and a PCT only model. The diagnostic abilities of these models as reflected by area under the curve of the receiver operating characteristic were 0.71 (95% confidence interval (CI): 0.66 to 0.76), 0.79 (95% CI: 0.75 to 0.83) and 0.73 (95% CI: 0.68 to 0.77) respectively. Calculating corresponding sensitivity and specificity for the presence of bacteremia after each step of adding a significant predictor in the model yielded that the PCT > 0.25 μg/l only model had the best diagnostic performance (sensitivity 0.95; 95% CI: 0.89 to 0.98, specificity 0.50; 95% CI: 0.46 to 0.55). Using PCT as a single decision tool, this would result in 40% fewer blood cultures being taken, while still identifying 94 to 99% of patients with bacteremia.The TTP of E. coli positive blood cultures was linearly correlated with the PCT log value; the higher the PCT the shorter the TTP (R(2) = 0.278, P = 0.007).

CONCLUSIONS

PCT accurately predicts the presence of bacteremia and bacterial load in patients with febrile UTI. This may be a helpful biomarker to limit use of blood culture resources.

Early changes of procalcitonin may advise about prognosis and appropriateness of antimicrobial therapy in sepsis

PURPOSE

The objective of this study is to define if early changes of procalcitonin (PCT) may inform about prognosis and appropriateness of administered therapy in sepsis.

METHODS

A prospective multicenter observational study was conducted in 289 patients. Blood samples were drawn on day 1, that is, within less than 24 hours from advent of signs of sepsis, and on days 3, 7, and 10. Procalcitonin was estimated in serum by the ultrasensitive Kryptor assay (BRAHMS GmbH, Hennigsdorf, Germany). Patients were divided into the following 2 groups according to the type of change of PCT: group 1, where PCT on day 3 was decreased by more than 30% or was below 0.25 ng/mL, and group 2, where PCT on day 3 was either increased above 0.25 ng/mL or decreased less than 30%.

RESULTS

Death occurred in 12.3% of patients of group 1 and in 29.9% of those of group 2 (P < .0001). Odds ratio for death of patients of group 1 was 0.328. Odds ratio for the administration of inappropriate antimicrobials of patients of group 2 was 2.519 (P = .003).

CONCLUSIONS

Changes of serum PCT within the first 48 hours reflect the benefit or not of the administered antimicrobial therapy. Serial PCT measurements should be used in clinical practice to guide administration of appropriate antimicrobials.

Early alterations of the innate and adaptive immune statuses in sepsis according to the type of underlying infection

Introduction

Although major changes of the immune system have been described in sepsis, it has never been studied whether these may differ in relation to the type of underlying infection or not. This was studied for the first time.

Methods

The statuses of the innate and adaptive immune systems were prospectively compared in 505 patients. Whole blood was sampled within less than 24 hours of advent of sepsis; white blood cells were stained with monoclonal antibodies and analyzed though a flow cytometer.

Results

Expression of HLA-DR was significantly decreased among patients with severe sepsis/shock due to acute pyelonephritis and intraabdominal infections compared with sepsis. The rate of apoptosis of natural killer (NK) cells differed significantly among patients with severe sepsis/shock due to ventilator-associated pneumonia (VAP) and hospital-acquired pneumonia (HAP) compared with sepsis. The rate of apoptosis of NKT cells differed significantly among patients with severe sepsis/shock due to acute pyelonephritis, primary bacteremia and VAP/HAP compared with sepsis. Regarding adaptive immunity, absolute counts of CD4-lymphocytes were significantly decreased among patients with severe sepsis/shock due to community-acquired pneumonia (CAP) and intraabdominal infections compared with sepsis. Absolute counts of B-lymphocytes were significantly decreased among patients with severe sepsis/shock due to CAP compared with sepsis.

Conclusions

Major differences of the early statuses of the innate and adaptive immune systems exist between sepsis and severe sepsis/shock in relation to the underlying type of infection. These results may have a major impact on therapeutics.

Pelvic floor dysfunction is not a risk factor for febrile urinary tract infection in adults

OBJECTIVE

To determine whether pelvic floor dysfunction (PFD) might be a risk factor for or consequence of febrile urinary tract infection (UTI), as UTI in adults is a common infection in which an underlying urological abnormality is often considered, and as in children, PFD is also thought to have a pathophysiological role in adults with UTI.

PATIENTS AND METHODS

A multicentre case-control study was conducted at 26 primary-care centres and at six Emergency Departments of regional hospitals. Cases were consecutive patients aged > or =18 years, who presented with febrile UTI. Controls were randomly selected subjects who visited their general practitioner for reasons other than UTI or fever. A validated pelvic floor questionnaire (the Pelvic Floor Inventories Leiden, PelFIs) was used to assess pelvic floor function.

RESULTS

Between October 2006 and December 2007, 153 cases were included; of these, the completed questionnaires of 102 (response rate 67%) were compared to those of 100 of 110 (response rate 91%) controls. The median age of cases and controls was 65 and 58 years, respectively; 40% of cases and controls were men. The percentage of PelFIs outcomes consistent with PFD were comparable between cases and controls, at 21% vs 23%, respectively (odds ratio 0.9, 95% confidence interval, CI, 0.4-1.78). In the multivariate analysis, comorbidity (odds ratio 4.9, 95% CI 2.2-11.1) and a history of UTI (odds ratio 2.5, 95% CI 1.0-6.1) were independent significant risk factors for febrile UTI, whereas PFD was not (odds ratio 1.0, 0.5-2.2). Within the group of cases, PFD was not associated with bacteriuria during assessment of PelFIs (odds ratio 1.1, 95% CI 0.4-3.5) and inversely related to a history of UTI within the previous year (odds ratio 0.2, 0.1-0.9).

CONCLUSIONS

PFD is common among adults but it does not seem to be a risk factor for febrile UTI.

Treatment duration of febrile urinary tract infection (FUTIRST trial): a randomized placebo-controlled multicenter trial comparing short (7 days) antibiotic treatment with conventional treatment (14 days)

BACKGROUND

Current guidelines on the management of urinary tract infection recommend treating febrile urinary tract infection or acute pyelonephritis with antimicrobials for at least 14 days. Few randomized trials showed the effectiveness of treatment durations of 5 to 7 days but this has only been studied in young previously healthy women.

METHODS/DESIGN

A randomized placebo-controlled double-blind multicenter non-inferiority trial in which 400 patients with community acquired febrile urinary tract infection will be randomly allocated to a short treatment arm (7 days of ciprofloxacin or 7 days of empirical beta-lactams +/- gentamicin intravenously with early switch to oral ciprofloxacin followed by 7 days of blinded placebo) or standard treatment arm (7 days of ciprofloxacin or 7 days of empirical beta-lactams +/- gentamicin intravenously with early switch to oral ciprofloxacin followed by 7 days of blinded ciprofloxacin). The study is performed in the Leiden region in which one university hospital, 6 general hospitals and 32 primary health care centers are clustered. Patients eligible for randomization are competent patients aged 18 years or above with a presumptive diagnosis of acute pyelonephritis as defined by the combination of fever, one or more symptoms of urinary tract infection and a positive urine nitrate test and/or the presence of leucocyturia. Exclusion criteria are known allergy to fluoroquinolones, female patients who are pregnant or lactating, polycystic kidney disease, permanent renal replacement therapy, kidney transplantation, isolation of ciprofloxacin-resistant causal uropathogen, renal abscess, underlying chronic bacterial prostatitis, metastatic infectious foci and inability to obtain follow-up. The primary endpoint is the clinical cure rate through the 10- to 18-day post-treatment visit. Secondary endpoints are the microbiological cure rate 10- to 18-day post-treatment, the 30- and 90-day overall mortality rate, the clinical cure rate 70- to 84-day post-treatment, relapse rate of UTI and adverse events or complications during 90 days of follow-up.

DISCUSSION

This study aims to demonstrate that 7 days of antimicrobial treatment is non-inferior as compared with 14 days of treatment in patients with febrile urinary tract infection. In addition, it will generate insights into the side-effects of antimicrobial treatment in relation to its duration. The study population will also include men, the elderly and patients with significant co-morbidity. Reflecting daily practice of primary health care and emergency departments, the results of this study can be generalized to other locations.

Vitamin E administration at the onset of fever prevents renal scarring in acute pyelonephritis

We evaluated the protective effects of antioxidant at the onset of fever on renal damage in a rat model of acute pyelonephritis. Twenty rats were allocated to four groups. In groups 1 to 3, the animals were given direct inoculation of Escherichia coli into the right kidney, and group four served as control. All rats in groups 1 to 3 were given once-daily intraperitoneal injections of ceftriaxon for five consecutive days, beginning on the third day after inoculation. The animals' body temperatures were monitored; as soon as body temperature reaches 38 degrees C, the rats in group 2 were given allopurinol co-treatment, whereas, in group 3, vitamin E co-treatment was started at fever onset. Both kidneys were excised 6 weeks later, for the evaluation of histopathologic changes, apoptotic damage, and concentrations of transforming growth factor-beta (TGF-beta). Only minimal changes were found in control samples. Pathologic scores of inflammation and fibrosis in group 1 were higher than in the vitamin E and allopurinol groups (P < 0.05). Apoptosis index was also decreased in groups 2 and 3, compared to group 1 (P < 0.05). There was no significant difference in average TGF-beta levels between study groups. These findings suggest that administration of vitamin E or allopurinol following the onset of fever can reduce renal damage in pyelonephritis.

Regional community-acquired urinary tract infections in Israel: diagnosis, pathogens, and antibiotic guidelines adherence: A prospective study

INTRODUCTION

The identification and treatment of hospitalized patients with community-acquired urinary tract infections (CAUTI) may be a challenge. The pathogens causing the infection and their relative proportions vary geographically and with time. This observational prospective study had three primary goals: (1) to estimate the likelihood of diagnosis of CAUTI upon admission; (2) to evaluate adherence to the institutional recommendations; (3) to assess the compatibility of the current local antibiotic recommendations with a pathogen's distribution and with its drug sensitivities.

METHODS AND RESULTS

Two hundred and twenty-three patients with positive urinary cultures fulfilling criteria for CAUTI were studied. Only 54 (24.2%) were diagnosed as having a urinary tract infection upon admission. Approximately 90% of the patients, who were correctly diagnosed, received the institutional recommended antibiotic therapy (ofloxacin or cefuroxime). Gram-negative intestinal flora comprised 86.1% (192 patients) of the causative microorganisms. Of these, 20.3% of the pathogens demonstrated resistance to ofloxacin and 19.8% to cefuroxime. The prevalence of Escherichia coli, the most common pathogen of UTI, significantly declined in the current study, from 70.5% in 1991 to 56% in 2000.

CONCLUSIONS

We observed a low sensitivity in diagnosing community-acquired urinary tract infections upon admission. In patients correctly diagnosed, the use of recommended antibiotics was high. A substantial percentage of the pathogens were resistant to the recommended antibiotics. This study stresses the need for frequent re-evaluation of the prevalence of pathogens involved in regional community-acquired urinary tract infections and the adjustment of the empirical first-line treatment accordingly.

Early changes of CD4-positive lymphocytes and NK cells in patients with severe Gram-negative sepsis

Introduction

Our aim was to define early changes of lymphocytes and of NK cells in severe sepsis and to correlate them with serum levels of soluble triggering receptor expressed on myeloid cells-1 (sTREM-1).

Methods

Blood was sampled from 49 patients with proven highly suspected infection by Gram-negative pathogens, within 12 hours of the advent of severe sepsis, and was also sampled from six healthy volunteers. White blood cells were targeted with monoclonal antibodies and were analyzed by flow cytometry. The concentrations of sTREM-1 were estimated by ELISA.

Results

The presence of CD3/CD4 cells was significantly lower (P < 0.0001) and that of NK cells significantly higher among patients with sepsis compared with controls (P = 0.011). The proportions (median ± standard error) of ANNEXIN-V/CD4/CD3-positive cells, of ANNEXIN-V/CD8/CD3-positive cells and of ANNEXIN-V/CD14-positive cells of the patient population were 7.41 ± 2.26%, 7.69 ± 3.42% and 1.96 ± 4.22%, respectively. Patients with NK cells >20% survived longer compared with those patients with NK cells ≤20% (P = 0.041), and patients with sTREM-1 concentrations >180 pg/ml survived longer compared with those patients with sTREM-1 concentrations ≤180 pg/ml (P = 0.042). A negative correlation was found between the percentages of ANNEXIN-V/CD4/CD3-positive cells and of CD3/CD4 cells (r_s = -0.305, P = 0.049), and a positive correlation was found between the serum sTREM-1 concentration and the percentage of NK cells (r_s = +0.395, P = 0.014). NK cells isolated from two healthy volunteers released sTREM-1 upon triggering with endotoxins.

Conclusion

Early severe sepsis is characterized by CD4-lymphopenia and increased NK cells, providing a survival benefit for the septic patient at percentages >20%. The survival benefit resulting from elevated NK cells might be connected to elevated serum levels of sTREM-1.

Diagnostic Investigation of Pyelonephritis

Urinary tract infections are common, especially among women, and cause significant morbidity. While prognosis is probably more dependent on whether or not an episode of urinary tract infection is complicated (ie, associated with functional, metabolic, or anatomic abnormalities of the urinary tract) or uncomplicated, anatomic localization of infection has important implications for therapy. Pyelonephritis is difficult to diagnose with a high degree of accuracy based on clinical findings alone. Radiologic imaging plays an important role in the diagnosis and management of selected patients. Noninvasive and inexpensive methods to allow accurate localization of infection are needed.