Clinical Characteristics of Uncomplicated Acute Pyelonephritis Caused by Escherichia coli and Klebsiella pneumoniae

INTRODUCTION

This study compared the clinical characteristics and antimicrobial susceptibility of uncomplicated acute pyelonephritis (APN) caused by Escherichia coli and Klebsiella pneumoniae.

METHODS

We retrospectively reviewed the medical records of patients with uncomplicated APNs caused by E. coli and K. pneumoniae admitted to Keimyung University Dongsan Hospital between February 2014 and December 2021.

RESULTS

We enrolled 497 patients (372 with E. coli infection, 125 with K. pneumoniae infection). Male, healthcare-associated infection, solid tumors, liver cirrhosis, chronic renal disease, solid organ transplantation, and antibiotic usage within the last 3 months were more strongly associated with K. pneumoniae uncomplicated APNs than with E. coli. Bacteremia and fever occurred more frequently in E. coli uncomplicated APNs. Antimicrobial resistance rates to piperacillin/tazobactam and carbapenem were higher in K. pneumoniae. Antimicrobial resistance rates to aztreonam and ciprofloxacin were lower in K. pneumoniae. Thirty-day mortality was more observed in K. pneumoniae group in univariate analysis, but this difference was not observed after adjustment. Male sex, ultimately fatal disease in McCabe, and prior antibiotic use within 3 months were more associated with K. pneumoniae.

CONCLUSIONS

Male, underlying diseases, and prior antibiotic use was more associated with K. pneumoniae. Further study will be needed that microbiome of each situation and the related with the distribution of the strains.

Clinical and microbiological characteristics of female patients with acute pyelonephritis who experienced urinary tract infections within the previous year

BACKGROUND

This study aimed to examine the clinical and microbiological characteristics of female patients with recurrent acute pyelonephritis (APN).

METHODS

A retrospective cohort study was conducted at a tertiary care hospital in South Korea from July 2019 to December 2021. All female patients aged ≥ 19 years who were diagnosed with community-acquired APN on admission were enrolled. The recurrent group included patients with APN who experienced urinary tract infections within the previous year. The clinical characteristics, types of causative organisms, major antibiotic resistance, and molecular characteristics of Escherichia coli strains were compared between the recurrent and non-recurrent groups.

RESULTS

A total of 285 patients with APN were analyzed, including 41 (14.4%) in the recurrent group. Compared to the non-recurrent group, the recurrent group had a higher Charlson Comorbidity Index (1.8 ± 2.1 vs. 1.1 ± 1.5; P = 0.01) and a higher proportion of bladder abnormalities, such as neurogenic bladder (12.2% vs. 2.0%; P = 0.001) and urinary catheterization (12.2% vs. 1.6%; P < 0.001). Escherichia coli was the most common causative organism in both groups. The proportion of Klebsiella pneumoniae (17.1% vs. 4.7%; P = 0.007) and Pseudomonas aeruginosa (5.7% vs. 0.5%; P = 0.014) as a causative organism was higher in the recurrent group. Regarding the microbiological characteristics of Escherichia coli, there were no significant differences in the proportion of antibiotic resistance, phylogenetic groups, resistance genes, and virulence factors between the two groups. Multivariable analysis showed that neurogenic bladder and a history of admission or antibiotic use during 1 year prior to inclusion were significantly associated with recurrent APN.

CONCLUSIONS

The proportion of causative organisms except Escherichia coli was higher in the recurrent group than in the non-recurrent group. Neurogenic bladder and a history of admission or antibiotic use during 1 year prior to inclusion were risk factors for recurrent APN.

A case of emphysematous pyelonephritis in an older man with poorly controlled type 2 diabetes mellitus

Emphysematous pyelonephritis (EPN) is a necrotizing bacterial infection characterized by gas retention and a poor prognosis. We present the case of a 75-year-old man who was diagnosed early with EPN and received multidisciplinary treatment. He had poorly controlled type 2 diabetes mellitus (DM) and chronic kidney disease (CKD), and was treated with oral hypoglycemic drugs, including a sodium-glucose co-transporter-2 inhibitor. He experienced the onset of back pain in the midsection of his back, tenderness in the costovertebral angle, and a high fever (> 39 °C), accompanied by tachycardia, hypotension, and tachypnea. The patient was diagnosed with pyelonephritis and septic shock. Immediate measures encompassing empirical antibiotic therapy, administration of noradrenaline, blood glucose regulation, and urethral catheterization were implemented. However, due to the persistent fever (> 38 °C) and lack of improvement in his condition, abdominal computed tomography (CT) was repeated on the fourth day. This revealed the presence of gas around the right kidney parenchyma, leading to a diagnosis of EPN that had evolved from acute pyelonephritis. Subsequently, percutaneous drainage of the right kidney parenchyma was performed. Subsequently, multidisciplinary treatment was continued, and his condition gradually improved. Clinicians should evaluate abdominal CT when acute pyelonephritis does not improve within a few days of antibiotic therapy. Disease progression from acute pyelonephritis to EPN should be considered in patients with DM and CKD.

Segmental renal vein thrombosis: An unusual complication of acute pyelonephritis

Renal vein thrombosis is not a common manifestation in the context of acute pyelonephritis. We report the case of a 29-year-old female diabetic patient that was admitted to our department for an episode of complicated acute pyelonephritis. Initial imaging showed a left lower polar abscess of 27 mm and urine cultures grew community acquired K. Pneumoniae. Two days after the patient was discharged, she was readmitted with worsening symptoms. Repeat imaging showed stability in the size of the abscess and revealed a left lower segmental vein thrombosis. The patient responded favorably to antibiotics and heparin-warfarin therapy.

An update on pyelonephritis: role of contrast enhancement ultrasound (CEUS)

Acute pyelonephritis (APN) is a bacterial infection causing inflammation of the kidneys. Diagnosis is usually based on clinical and laboratory findings. Imaging is required if a complication is suspected in acute pyelonephritis to assess the nature and extent of the lesions and to detect underlying causes. CT represents the current imaging modality of choice in clinical practice. CEUS is an alternative that has been proven to be equally accurate in the detection of acute pyelonephritis renal lesions. CEUS allows us to distinguish small simple nephritic involvement from abscess complications and to follow their evolution over time during antibiotic therapy. The absence of ionizing radiation and the lack of nephrotoxicity make CEUS an ideal tool in the study of pyelonephritis.

Incidence of renal scarring on technetium-99 m dimercaptosuccinic acid renal scintigraphy after acute pyelonephritis, acute focal bacterial nephritis, and renal abscess

OBJECTIVE

To evaluate the association between the incidence of renal scarring on technetium-99 m dimercaptosuccinic acid (DMSA) renal scintigraphy and the severity of renal parenchymal infections, such as acute pyelonephritis (APN), acute focal bacterial nephritis (AFBN), and renal abscess, based on computed tomography (CT) diagnosis.

METHODS

Sixty-one children with renal parenchymal infections were included and classified into two groups: those with (renal scarring group) and without renal scarring (non-renal scarring group) on chronic-phase DMSA renal scintigraphy. The severity of renal parenchymal infection was classified into three grades using CT: APN, AFBN, and renal abscess as grades 1, 2, and 3, respectively. The severity of renal parenchymal infection, vesicoureteral reflux (VUR) grade, and intrarenal reflux occurrence during voiding cystourethrography (VCUG) were evaluated between the renal and non-renal scarring groups. Fisher's exact test and Mann-Whitney U test were used for statistical analysis.

RESULTS

Renal scars were detected in 28 (45.9%) of the 61 patients. We found that 2/9 (22.2%), 18/41 (43.9%), and 8/11 (72.7%) patients with APN (grade 1), AFBN (grade 2), and renal abscess (grade 3) had renal scarring, respectively. There was a significant difference in the grade of severity of renal parenchymal infection between the renal (median = 2 [interquartile range, 2-3]) and non-renal (median = 2 [interquartile range, 2-2]) scarring groups (p = 0.023). There was a significant difference in the grade of VUR between the renal (median = 3 [interquartile range, 0-4]) and non-renal (median = 0 [interquartile range, 0-2]) scarring groups (p = 0.004). No significant difference in intrarenal reflux occurrence was observed between the renal (present/absent: 3/25) and non-renal (present/absent: 0/29) scarring groups (p = 0.112).

CONCLUSION

Our results showed that pediatric patients with renal scarring on chronic-phase DMSA renal scintigraphy tended to have a more severe renal infection.

Sepsis following acute pyelonephritis caused by Trueperella bernardiae: a case report and literature review

BACKGROUND

Trueperella bernardiae is a coryneform, gram-positive bacterium that is a commensal of the skin and upper respiratory tract. It is treated as a contaminant and rarely causes infections. Blood, urine, and abscesses have been previously reported as the most common sites of infection. Infections caused by T. bernardiae are rarely reported in bedridden very old patients with reduced activities of daily living (ADL). In this report, we describe a case of sepsis due to acute pyelonephritis caused by T. bernardiae in a very old patient with impaired ADL.

CASE PRESENTATION

A 94-year-old woman had a home visit from her local physician. She was bedridden and used diapers. On the day of admission, she presented with fever and dyspnea and was admitted with a diagnosis of sepsis associated with acute pyelonephritis. T. bernardiae was detected in blood and urine cultures; furthermore, multiple bacteria were detected in a urine culture. She was treated with ampicillin/sulbactam 3 g every 12 h on the day of admission. The fever was controlled, and inhaled oxygen 1 L/min via a nasal cannula was administered for dyspnea until hospitalization day 2. On hospitalization day 2, her fever resolved to 36 °C. Antimicrobials were de-escalated and changed to cephazolin and then to cephalexin on hospitalization days 9 and 16, respectively, and were continued until day 22. On hospitalization day 28, the urinary tract infection flared up; however, her fever resolved by hospitalization day 38 after the re-administration of antimicrobial agents. She was discharged on hospitalization day 60.

CONCLUSIONS

We encountered a rare case of sepsis following acute pyelonephritis caused by T. bernardiae infection. When bedridden, diaper-using, very old patients present with urinary tract infections caused by multiple bacteria, the presence of rare opportunistic organisms, such as T. bernardiae, should be considered.

ACR Appropriateness Criteria® Acute Pyelonephritis: 2022 Update

Acute pyelonephritis (APN) is a severe urinary tract infection (UTI) that has the potential to cause sepsis, shock, and death. In the majority of patients, uncomplicated APN is diagnosed clinically and is responsive to treatment with appropriate antibiotics. In patients who are high risk or when treatment is delayed, microabscesses may coalesce to form an acute renal abscess. High-risk patients include those with a prior history of pyelonephritis, lack of response to therapy for lower UTI or for APN, diabetes, anatomic or congenital abnormalities of the urinary system, infections by treatment-resistant organisms, nosocomial infection, urolithiasis, renal obstruction, prior renal surgery, advanced age, pregnancy, renal transplant recipients, and immunosuppressed or immunocompromised patients. Pregnant patients and patients with renal transplants on immunosuppression are at an elevated risk of severe complications. Imaging studies are often requested to aid with the diagnosis, identify precipitating factors, and differentiate lower UTI from renal parenchymal involvement, particularly in high-risk individuals. Imaging is usually not appropriate for the first-time presentation of suspected APN in an uncomplicated patient. The primary imaging modalities used in high-risk patients with suspected APN are CT, MRI, and ultrasound, although CT was usually not appropriate for initial imaging in a pregnant patient with no other complications. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer-reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which peer-reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

An Unusual Case of High-Grade Non-Hodgkin Lymphoma Masquerading as Acute Pyelonephritis with Acute Kidney Injury

Renal involvement in non-Hodgkin lymphoma (NHL) has myriad of morphological features. We discuss an unusual case who presented as acute pyelonephritis (leucocytosis and acute kidney injury), ovarian mass and compressive myelopathy finally diagnosed as Non Hodgkins Lymphoma.

A case of acute focal bacterial nephritis with acute kidney injury presenting as acute abdomen

Acute focal bacterial nephritis (AFBN) refers to the bacterial infection of the renal parenchyma without abscess formation. Although AFBN has mainly been reported in pediatric patients, it may be underdiagnosed in adults as it resembles acute pyelonephritis in its clinical presentation. However, the symptoms suggesting acute abdomen is an important clue to diagnose AFBN, which requires additional imaging studies such as contrast-enhanced computed tomography (CECT). Here, we present the case of a 49-year-old female presenting to our emergency room with acute abdomen as well as acute kidney injury (AKI). CECT was performed to rule out critical etiologies of severe abdominal pain and the results revealed multifocal wedge-shaped shadows in the right kidney and diffuse enlargement of bilateral kidneys. We diagnosed the patient with AFBN and treated her through temporal hemodialysis (two sessions) and antibiotics for 23 days. Although AKI associated with AFBN has rarely been reported, her renal dysfunction and other symptoms were completely improved. In conclusion, clinicians should be aware of AFBN and be cautious to avoid the unnecessary invasive interventions.

Rotula aquatica Lour. mitigates oxidative stress and inflammation in acute pyelonephritic rats

The current study evaluates the efficacy of methanolic extract of Rotula aquatica Lour. (MERA) against inflammatory changes associated with acute pyelonephritis. The antioxidant enzymes such as SOD, CAT, GPx, GR and oxidative stress markers like GSH content, malondialdehyde (MDA) level, nitrate level, reactive oxygen species (ROS) level and renal toxicity markers were evaluated in this study. The mRNA level expression of Toll-like receptor 4 (TLR-4), nuclear transcription factor kappa B (NF-κB), tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and Tamm Horsfall protein (THP) were studied by RT-PCR analysis. The oral administration of MERA increases the antioxidant enzyme status in pyelonephritis rat. The elevated levels of oxidative stress markers in pyelonephritic rats were ameliorated by the administration of MERA at 100 mg/kg and 200 mg/kg bwt of the rat. The mRNA level expression of major genes were restored to normal level by MERA.

Relationship between the appropriateness of antibiotic treatment and clinical outcomes/medical costs of patients with community-acquired acute pyelonephritis: a multicenter prospective cohort study

BACKGROUND

Inappropriate use of antibiotics not only increases antibiotic resistance as collateral damage but also increases clinical failure rates and medical costs. The purpose of this study was to determine the relationship between the appropriateness of antibiotic prescription and outcomes of community-acquired acute pyelonephritis (CA-APN).

METHODS

A multicenter prospective cohort study was conducted at eight hospitals in Korea between September 2017 and August 2018. All hospitalized patients aged ≥ 19 years who were diagnosed with CA-APN on admission were recruited. The appropriateness of empirical and definitive antibiotics, as well as the appropriateness of antibiotic treatment duration and route of administration, was evaluated in accordance with the guideline and expert opinions. Clinical outcomes and medical costs were compared between patients who were administered antibiotics 'appropriately' and 'inappropriately.'

RESULTS

A total of 397 and 318 patients were eligible for the analysis of the appropriateness of empirical and definitive antibiotics, respectively. Of them, 10 (2.5%) and 18 (5.7%) were administered 'inappropriately' empirical and definitive antibiotics, respectively. Of the 119 patients whose use of both empirical and definitive antibiotics was classified as 'optimal,' 57 (47.9%) received antibiotics over a longer duration than that recommended; 67 (56.3%) did not change to oral antibiotics on day 7 of hospitalization, even after stabilization of the clinical symptoms. Patients who were administered empirical antibiotics 'appropriately' had shorter hospitalization days (8 vs. 10 days, P = 0.001) and lower medical costs (2381.9 vs. 3235.9 USD, P = 0.002) than those who were administered them 'inappropriately.' Similar findings were observed for patients administered both empirical and definitive antibiotics 'appropriately' and those administered either empirical or definitive antibiotics 'inappropriately'.

CONCLUSIONS

Appropriate use of antibiotics leads to better outcomes, including reduced hospitalization duration and medical costs.

Does delaying ureteral stent placement lead to higher rates of preoperative acute pyelonephritis during pregnancy?

BACKGROUND

Pregnancy with renal colic may cause pyelonephritis, decreased renal function, systemic infection and even shock in pregnant women, and cause premature birth and other adverse pregnancy outcomes. When surgery is necessary, the relationship between timing of the operation and the outcome of the mother and child are not known.

AIM

To investigate the association between time to ureteral stent placement and clinical outcomes of patients with renal colic during pregnancy.

METHODS

In this retrospective study, pregnant women with renal colic who underwent surgery were studied. Maternal preoperative acute pyelonephritis (PANP), pregnancy outcome, and length of hospital stay (LOS) were compared between the two groups.

RESULTS

100 patients were included in the analysis, median age was 30 years. Median time to ureteral stent placement was 48 h (interquartile range, 25-96 h), and 32 patients (32%) were diagnosed with PANP. PANP was closely related to hospitalization costs, re-admission to the hospital due to urinary tract infection after surgery and premature delivery. Multivariate analysis found that stone location and time from pain to admission were related to PANP.

CONCLUSION

Both early and delayed surgery are safe and effective for the treatment of renal colic during pregnancy. Early surgery may be superior to a delayed procedure due to shorter LOS. For pregnant patients with renal colic, delayed surgery within 48 h is not related to the clinical outcome of the mother and child. However, the time from pain to hospital admission was related to PANP.

First-generation cephalosporins for the treatment of complicated upper urinary tract infection in adults: A systematic literature review

INTRODUCTION

Complicated upper urinary tract infection (UTI) is a significant cause of infectious morbidity and in-hospital antibiotic therapy. However, the use of first-generation cephalosporins in this scenario is not clearly defined.

OBJECTIVE

Evaluate the efficacy and safety of first-generation cephalosporins for community-acquired complicated upper UTI in adults requiring hospital care.

METHODS

Systematic review by searching in electronic databases (MEDLINE, Embase, CENTRAL) and trials registers, with screened and selected the references, data extraction and risk of bias assessment. The results were presented in a narrative synthesis.

RESULTS

Seven randomized clinical trials were included. We did not identify statistically significant differences when comparing first-generation cephalosporins with other antimicrobials for outcomes of clinical cure, length of hospital stay, and reinfection. However, a lower probability of microbiological cure and a higher probability of relapse were identified in the first-generation cephalosporin group in 3 of 7 studies and in 2 of 5 studies, respectively. No serious adverse effects were reported.

CONCLUSIONS

First-generation cephalosporins could be a potential therapy in this setting, nevertheless it should be considered the low quality of evidence for analyzed outcomes, due to limitations of risk of bias and imprecision. It is essential to carry out comparative studies in which the benefits and harms of these antibiotics are evaluated.

Increasing rates of extended-spectrum B-lactamase-producing Escherichia coli and Klebsiella pneumoniae in uncomplicated and complicated acute pyelonephritis and evaluation of empirical treatments based on culture results

Increasing rates of extended-spectrum beta-lactamase (ESBL) producing E. coli and K. pneumoniae over time made empirical treatment complicated. Knowing local antimicrobial resistance patterns of common pathogens can make it easier to decide on empirical antibiotics. We aimed to investigate the prevalence and risk factors of ESBL positivity of E. coli and K. pneumoniae strains in uncomplicated and complicated pyelonephritis acquired in community and healthcare associations and to evaluate the appropriateness of empirical treatment. Adult patients hospitalized with diagnosis of community-acquired or healthcare-associated uncomplicated/complicated pyelonephritis initiated empirical antimicrobial therapy were included in the study. Appropriateness of empirical treatment at 48-72 h based on culture results and treatment modifications were evaluated. A total of 369 uncomplicated (94) and complicated (275) episodes of pyelonephritis were evaluated. The most common agents were E. coli (71.0%) and K. pneumoniae (17.7%), and the ESBL-production rate was 64.4%, and higher in healthcare-associated pyelonephritis (P 0.013). Being of healthcare-associated infection, previous antibiotic use, and presence of urinary catheters were independent risk factors for ESBL-producing E. coli and K. pneumoniae (P 0.009, < 0.001, and 0.024, respectively). The treatment inappropriateness was mostly associated with use of ceftriaxone (56.3%) (P < 0.001). Treatment has escalated in 41.5% of ceftriaxone-initiated patients, in only 8.8% and 9.5% ertapenem and piperacillin-tazobactam-initiated patients, respectively. ESBL-production rates are quite high even in community-acquired infections. The use of broad-spectrum antibiotics covering ESBL-producing pathogens to increase the appropriateness of empirical treatment and then narrowing treatment based on culture results appears a better and life-saving choice.

Dexamethasone to prevent kidney scarring in acute pyelonephritis: a randomized clinical trial

BACKGROUND

Urinary tract infection (UTI) is one of the most common bacterial infections in childhood and is associated with long-term complications. We aimed to assess the effect of adjuvant dexamethasone treatment on reducing kidney scarring after acute pyelonephritis (APN) in children.

METHODS

Multicenter, prospective, double-blind, placebo-controlled, randomized clinical trial (RCT) where children from 1 month to 14 years of age with proven APN were randomly assigned to receive a 3-day course of either an intravenous corticosteroid (dexamethasone 0.30 mg per kg/day) twice daily or placebo. The late technetium 99 m-dimercaptosuric acid scintigraphy (> 6 months after acute episode) was performed to assess kidney scar persistence. Kidney scarring risk factors (vesicoureteral reflux, kidney congenital anomalies, or urinary tract dilatation) were also assessed.

RESULTS

Ninety-one participants completed the follow-up and were finally included (dexamethasone n = 49 and placebo n = 42). Both groups had similar baseline characteristics. Twenty participants showed persistent kidney scarring after > 6 months of follow-up without differences in incidence between groups (22% and 21% in the dexamethasone and placebo groups, p = 0.907). Renal damage severity in the early DMSA (β = 0.648, p = 0.023) and procalcitonin values (β = 0.065 p = 0.027) significantly modulated scar development. Vesicoureteral reflux grade showed a trend towards significance (β = 0.545, p = 0.054), but dexamethasone treatment showed no effect.

CONCLUSION

Dexamethasone showed no effect on reducing the risk of scar formation in children with APN. Hence, there is no evidence for an adjuvant corticosteroid treatment recommendation in children with APN. However, the study was limited by not achieving the predicted sample size and the expected scar formation.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT02034851. Registered in January 14, 2014. "A higher resolution version of the Graphical abstract is available as Supplementary information."

Demographic, clinical, and laboratory factors associated with renal parenchymal injury in Iranian children with acute pyelonephritis

Background

The association between renal parenchyma changes on dimercaptosuccinic acid (DMSA) scans and demographic, clinical, and laboratory markers was assessed in pediatric patients with acute pyelonephritis.

Methods

A retrospective study of 67 Iranian babies and children aged 1-month to 12-year with APN was conducted between 2012 and 2018. The presence of renal parenchymal involvement (RPI) during APN was determined using technetium-99m DMSA during the first 2 weeks of hospitalization. The association of DMSA results with demographic data, clinical features (hospitalization stay, fever temperature and duration), and laboratory parameters such as pathogen type, and hematological factors (ESR, CRP, BUN, Cr, Hb, and WBC) was evaluated.

Results

92.5% of children with an average age of 43.76 ± 5.2 months were girls. Twenty-four children (35.8%) did not have renal parenchymal injury (RPI), while 26 (38.8%) and 17 (25.4%) patients showed RPI in one and both kidneys, respectively. There was no significant association between RPI and mean ESR, CRP, BUN, and WBC. However, there were significant associations between RPI and higher mean levels of Cr, Hb, and BMI.

Conclusions

Low BMI and Hb levels and increased Cr levels might be indicative of the presence of RPI in children with APN.

Febrile urinary tract infection in children: changes in epidemiology, etiology, and antibiotic resistance patterns over a decade

BACKGROUND

Understanding the epidemiology and prevalence of febrile urinary tract infection (fUTI) in children is important for risk stratification and selecting appropriate urine sample collection candidates to aid in its diagnosis and treatment.

PURPOSE

This study aimed to analyze the epidemiology, etiology, and changes in antibiotic susceptibility patterns of the first fUTI in children.

METHODS

This retrospective observational cohort study included children younger than 19 years of age who were diagnosed and treated for their first fUTI in 2006-2016. Electronic medical records were analyzed and radiologic images were evaluated.

RESULTS

A total of 359 patients (median age, 5.1 months; interquartile range, 3.0-10.5 months) fit the inclusion criteria; of them, 78.0% (n=280) were younger than 12 months old. The male to female ratio was 5.3:1 for patients aged 0-2 months, 2.1:1 for those 3-5 months, and 1.6:1 for those 6-11 months. Beyond 12 months of age, there was a female predominance. Escherichia coli was the leading cause (83.8%), followed by Enterococcus species (6.7%), and Klebsiella pneumoniae (3.6%). Significant yearly increases in the proportions of multidrug-resistant strains (P<0.001) and extended-spectrum beta-lactamase (ESBL) producers (P<0.001) were observed. In patients with vesicoureteral reflux (VUR), the overall recurrence rate was 53.6% (n=15). A significantly higher recurrence rate was observed when the fUTI was caused by an ESBL versus non-ESBL producer (75.0% vs. 30.0%, P=0.03).

CONCLUSION

fUTI was most prevalent in children younger than 12 months of age and showed a female predominance in patients older than 12 months of age. The proportion of ESBL producers causing fUTI is increasing. Carbapenems, rather than noncarbapenems, should be considered for treating fUTI caused by ESBL-producing enteric gram-negative rods to reduce short-term recurrence rates in children with VUR.

New strategy of color and power doppler sonography combined with DMSA in the assessment of acute pyelonephritis in infants

Background

The purpose of this study was to evaluate the clinical value of color and power doppler sonography (CPDS) when combined it with 99mTc-dimercaptosuccinic acid scintigraphy (DMSA) in assessment of acute pyelonephritis (APN) in infants.

Methods

A total of 79 children with APN admitted to our hospital from June 2016 to Jan 2019 were enrolled, including 52 boys and 27 girls, age range 1 month to 3 years old. All cases followed the diagnostic criteria for acute pyelonephritis and excluded anatomical abnormalities of urinary system. All 79 patients were examined by urinary ultrasonography (US), CPDS, and DMSA within 48 h of fever and analyzed the clinical value of combining the two methods in the assessment of APN in infants.

Results

Among 79 children, urinary ultrasonography revealed 2 cases of renal cortical echo changes, both located in the upper pole of the kidney, 24 cases of kidney enlargement, and 1 case of left kidney shrinkage. Ninety-five kidneys were shown to be diseased with DMSA, while 105 kidneys abnormal by CPDS. The sensitivity of CPDS was 69.4%, and the specificity was 38.1%. In children younger than 6 months, the sensitivity of CPDS was 56.9%, which was 84.2% in childeren between 6 months to 1 year, and 94.4% from 1 to 3 years old, respectively. The corresponding specificity of CPDS was 44.1, 26.7, and 35.7%. There was no significant correlation between CPDS levels and DMSA positive results. The abnormal rate of intermediate part in the kidneys was significantly lower than that in the upper and lower poles. Children with abnormal CPDS have a greater risk of renal scarring(p < 0.05).

Conclusion

Abnormalities detected by CPDS in a cohort of infants with APN poorly correlated with DMSA findings. But the sensitivity of CPDS is highly age-related, it can be used as a non-invasive helpful tool for early diagnosis of acute pyelonephritis in infants older than 6 months old.

Diagnosis and management of community-acquired urinary tract infection in infants and children: Clinical guidelines endorsed by the Saudi Pediatric Infectious Diseases Society (SPIDS)

Urinary tract infection (UTI) is the most common bacterial disease in childhood worldwide and may have significant adverse consequences, particularly for young children. In this guideline, we provide the most up-to-date information for the diagnosis and management of community-acquired UTI in infants and children aged over 90 days up to 14 years. The current recommendations given by the American Academy of Pediatrics Practice guidelines, Canadian Pediatric Society guideline, and other international guidelines are considered as well as regional variations in susceptibility patterns and resources. This guideline covers the diagnosis, therapeutic options, and prophylaxis for the management of community-acquired UTI in children guided by our local antimicrobial resistance pattern of the most frequent urinary pathogens. Neonates, infants younger than three months, immunocompromised patients, children recurrent UTIs, or renal abnormalities should be managed individually because these patients may require more extensive investigation and more aggressive therapy and follow up, so it is considered out of the scope of these guidelines. Establishment of children-specific guidelines for the diagnosis and management of community-acquired UTI can reduce morbidity and mortality. We present a clinical statement from the Saudi Pediatric Infectious Diseases Society (SPIDS), which concerns the diagnosis and management of community-acquired UTI in children.

Clinical manifestations, laboratory markers, and renal ultrasonographic examinations in 1-month to 12-year-old Iranian children with pyelonephritis: a six-year cross-sectional retrospective study

BACKGROUND

Upper urinary tract infection (UTI) or pyelonephritis may increase the pathogenesis rate and risk of severe complications in children due to kidney atrophy.

OBJECTIVE

A set of clinical symptoms, laboratory markers, and ultrasound findings were assessed to achieve the early diagnosis and prognosis of pyelonephritis in hospitalized pediatrics.

METHODS

A cross-sectional study with 104 Iranian children (95 girls and 9 boys) aged 1 month to 12 years with acute pyelonephritis during 2012-2018 was conducted. The ultrasound examination of kidneys and urinary tract during hospitalization, the incidence of clinical symptoms, and laboratory markers in blood and urine were monitored to identify the best predictive factors of early diagnosis of this bacterial infection.

RESULTS

Three-fourth of the patients had one of the four clinical symptoms of abdominal pain, constipation, dysuria, and vomiting, while others were asymptomatic. A much frequency of pyuria (88.46%), Escherichia coli in urine (92.31%), leukocytosis (81.73%), and high ESR (> 10 mm/h, 92.30%) and CRP (> 10 mg/L, 82.82%) was observed. The kidney and urinary tract ultrasonography only in 32.7% of children revealed findings in favor of pyelonephritis (cystitis, ureteral stones, and hydronephrosis).

CONCLUSION

There was a high frequency of clinical signs and laboratory markers associated with pyelonephritis. Ultrasound alone was not an efficient tool to track febrile UTI as most patients presented normal sonography.

Left-to-right crossed fused renal ectopia with pyelonephritis mimicking appendix mass

Crossed fused renal ectopia (CFRE) is an uncommon developmental anomaly of the genitourinary system whereby the two kidneys are located on the same side of the body and joined together, while the ureter of the ectopic kidney still enters the bladder in its normal side. CFRE has variable clinical presentations and usually discovered incidentally when patients are investigated for abdominal complaints. Treatment may be conservative when renal function is preserved with no associated symptomatic urological complications. Highlighted here is the unusual presentation of left-to-right CFRE with acute pyelonephritis as an appendix mass in a 19-year-old female.

Study on risk factors, bacterial species, and drug resistance of acute pyelonephritis associated with ureteral stent after percutaneous nephrolithotomy

The purpose of this study is to explore the risk factors, bacterial species, and drug resistance of acute pyelonephritis (AP) associated with ureteral stent after percutaneous nephrolithotomy (PCNL) and to provide reference for clinical intervention. The clinical data of 415 patients with indwelling ureteral stent after PCNL from December 2016 to May 2019 were analyzed retrospectively. The patients were divided into infection group (n = 54) and non-infection group (n = 361) according to whether patients had AP. Patients' clinical data, blood and urine bacterial culture, and drug sensitivity were collected and analyzed. The incidence of AP associated with ureteral stent after PCNL was 13.01% and diabetes mellitus (P = 0.001), postoperative stone residue (P = 0.002), urinary leucocytes ≥ 100/HP (P = 0.018), positive urine culture results (P = 0.001), ureteral stent retention time ≥ 8 weeks (P = 0.004), and high S.T.O.N.E. score (P = 0.014) are independent risk factors for it. Escherichia coli (40.54%, 47.82%), Klebsiella pneumoniae (16.21%, 15.21%), Pseudomonas aeruginosa (10.81%, 4.34%), Enterococcus faecalis (21.6%, 19.56%), and epidermis Staphylococci (10.81%, 13.33%) are the main pathogens in blood and urine. The main sensitive drugs of pathogenic bacteria are imipenem, meropenem, tigecycline, piperacillin/tazobactam, ceftazidime, linezolid, teicoplanin, levofloxacin, vancomycin, tigecycline, etc., while levofloxacin, norfloxacin, penicillin G, first, and second-generation cephalosporins showed a strong drug resistance rate (> 70%). This study found that diabetes, postoperative stone residuals, urinary leukocytes ≧ 100 cells/HP, positive urine culture results, ureteral stent indwelling time ≧ 8 weeks, and high S.T.O.N.E. score were independent of AP associated with ureteral stent after PCNL risk factors and Escherichia coli is the main pathogenic bacteria and shows drug resistance.

Levofloxacin versus ceftriaxone for treatment of acute pyelonephritis in Iranian adults

INTRODUCTION

Acute pyelonephritis is among the most common bacterial infections. Options for initial treatment of pyelonephritis include an extended-spectrum cephalosporin or a fluoroquinolone. In this study, we aimed to compare the clinical outcomes of patients receiving ceftriaxone to those who received levofloxacin for the treatment of acute pyelone-phritis.

METHODS

In this randomized, open-label trial, hospitalized adults with acute pyelonephritis were treated with ceftriaxone (1g IV every 12 hours) or levofloxacin (750 mg IV daily) for at least 7 days. Clinical and microbiological characteristics were compared among patients treated with ceftriaxone and levofloxacin.

RESULTS

A total of 59 patients were randomized, 30 to the ceftriaxone group and 29 to the levofloxacin group. The clinical response for 68.0% of patients in the ceftriaxone group and 56.0% of patients in the levofloxacin group were cured. The mi-crobiological response (pathogen eradication rates) was 68.7% in the ceftriaxone group and 21.4% in the levofloxacin group.(P value=0.00028) Escherichia coliwas the most common pathogen (n = 31), followed by Klebsiella pneumoniae(n = 21). High resistance rates were detected for cotrimoxazole (55%), ciprofloxacin (48%), and ceftriaxone (34.4%) in isolat-ed E.coli. Likewise, all K. pneumoniaeisolates were resistant to ciprofloxacin.

CONCLUSIONS

Our study indicates that ceftriaxone was more effective than levofloxacin in the treatment of acute pyelone-phritis, on the basis of microbiological response, but there were no statistically significant differences between the treatment groups in the rates of clinical cure.The resistance of uropathogens to the most used antibiotics was relatively high. Choosing the treatment regimen based on susceptibility testing results and shortening the duration of the therapy are now recommend-ed to be the most important approaches to decrease the spread of antibiotic resistance worldwide.

Scrub typhus as a rare cause of acute pyelonephritis: case report

BACKGROUND

Scrub typhus can present with atypical signs and symptoms such as those of acute kidney injury, gastroenteritis, pneumonitis, and acute respiratory distress syndrome. Meningitis, encephalitis, and hepatic dysfunction have also been reported, particularly in severe cases with multisystem involvement. Scrub typhus has never been reported in the literature to cause urinary tract infections (UTIs) which includes cystitis and pyelonephritis.

CASE PRESENTATION

A 45-year old male presenting to the outpatient unit with fever, right flank pain, and burning micturition for three days was initially treated for UTI. However, he returned to the hospital on the fourth day of illness with persistent symptoms. He was hospitalized, with intravenous (IV) ceftriaxone. Computerized tomography scan of his abdomen-pelvis showed features of acute pyelonephritis, so his antibiotics were upgraded to meropenem and teicoplanin. Despite this, the patient's condition deteriorated. Laboratory investigations showed multisystem involvement: decreasing platelets, raised creatinine, and deranged liver panel. As Kathmandu was hit by dengue epidemic during the patient's hospitalization, on the seventh day of his illness, blood samples were sent for tropical fever investigation. All tests came out negative except for scrub typhus-IgM antibodies positive on rapid diagnostic test. The patient's symptoms subsided after 48 h of starting doxycycline and he became fully asymptomatic four days later. Fever did not recur even after discontinuing other IV antibiotics, favoring scrub typhus disease rather than systemic bacterial sepsis.

CONCLUSIONS

Scrub typhus is an emerging infectious disease of Nepal. Therefore, every unexplained fever cases (irrespective of clinical presentation) should be evaluated for potential Rickettsiosis. Moreover, for cases with acute pyelonephritis, atypical causative agents should be investigated, for example scrub typhus in this case.

Presepsin and procalcitonin as predictors of sepsis based on the new Sepsis-3 definitions in obstructive acute pyelonephritis

Background

Acute pyelonephritis (APN) with obstructive uropathy often causes sepsis. Recently, sepsis was redefined using the sequential organ failure assessment (SOFA) score, based on the new Sepsis-3 criteria. We investigated predictors for sepsis using this new definition in patients with obstructive APN associated with upper urinary tract calculi.

Methods

We retrospectively evaluated patients who were admitted to our hospital for treatment of obstructive APN associated with upper urinary tract calculi. Blood and urine samples were collected before treatment of obstructive APN. Treatment included adequate antimicrobial therapy and emergency drainage to decompress the renal collecting system. We diagnosed sepsis using the new Sepsis-3 definition. We assessed predictors for sepsis by multivariate logistic regression analysis.

Results

Sixty-one patients were included in this study. Overall, all patients underwent emergency drainage, and 11 (18.0%) patients showed sepsis. There were no significant differences in performance status or comorbidities between sepsis and non-sepsis groups. Platelet count and serum albumin level were significantly lower in the sepsis group than in the non-sepsis group (p = 0.001 and p = 0.016, respectively). Procalcitonin (PCT) and presepsin (PSEP) levels were significantly higher in the sepsis group than in the non-sepsis group (p < 0.001 and p < 0.001, respectively). Multivariate analysis showed that PCT elevation (OR = 13.12, p = 0.024) and PSEP elevation (OR = 13.13, p = 0.044) were independent predictors for sepsis.

Conclusions

Elevation of PCT and PSEP levels before treatment might predict the development of sepsis in patients with obstructive APN.

Are oral cefuroxime axetil, cefixime and cefditoren pivoxil adequate to treat uncomplicated acute pyelonephritis after switching from intravenous therapy? A pharmacokinetic/pharmacodynamic perspective

OBJECTIVES

The goal of this study is to assess, by means of pharmacokinetic/pharmacodynamic (PK/PD) analysis using the Monte Carlo simulation, the adequacy of oral cephalosporins cefuroxime axetil, cefixime and cefditoren at different dosing regimens as switch therapy after intravenous cephalosporin treatment in uncomplicated acute pyelonephritis.

METHODS

The methodology included: (i) dosing regimen selection and acquisition of pharmacokinetic data; (ii) microbiological data acquisition; and (iii) Monte Carlo simulation to estimate the PTA (probability of PK/PD target attainment) and CFR (cumulative fraction of response), as indicators of treatment success.

RESULTS

At the current susceptibility breakpoints defined by EUCAST and CLSI for either cefuroxime axetil or cefixime, the probability of bactericidal target attainment is zero for the dosage regimens simulated. Considering the bactericidal target %fT_>MIC>70%, the likelihood of the cefuroxime 500-mg q8h regimen or the cefixime 200-mg q12h regimen producing this exposure or achieving this target is only above 90% for organisms yielding MICs≤0.5mg/l and MICs≤0.25mg/l, respectively. Cefditoren pivoxil 400mg q12h provided probabilities of bactericidal target attainment of 80% or higher for MICs≤0.03mg/l, and ≤0.25mg/l if considering total instead of free drug concentrations.

CONCLUSIONS

The results of the PK/PD target attainment analysis reveal that the likelihood of treatment success based upon the current breakpoints proposed by either EUCAST or CLSI is low. Of the three cephalosporins, cefixime 400mg q12h prove to be the best option in oral APN treatment, although this regimen is currently off label.

Clinical Predictors Implicated in the Incidence of Acute Pyelonephritis during the Antepartum Period: A Population-Based Cohort Study

INTRODUCTION

Acute pyelonephritis (APN) is a common infection during pregnancy that increases the risk of unfavorable maternal and fetal outcomes. However, it has not been clearly elucidated which demographic and clinical characteristics are associated with the incidence of APN during pregnancy.

OBJECTIVE

This population-based cohort study aimed to determine the risk factors for APN during pregnancy.

METHODS

Using the database of the Health Insurance Review and Assessment Service of South Korea, we enrolled Korean women who delivered infants between 2010 and 2014 in Korea and had complete health examination records within 1 year of pregnancy. We performed multivariate logistic regression analysis to evaluate the risk factors for APN during pregnancy.

RESULTS

Of 370,248 women, 2,526 (0.7% of the total participants) were treated for APN while in hospitalization during pregnancy. Younger age, history of previous APN within 1 year of pregnancy, and abnormal results of health examination before pregnancy, such as high fasting glucose level (>100 mg/dL) and proteinuria, were associated with an increased risk of APN during pregnancy.

CONCLUSION

Certain maternal demographic and clinical characteristics were associated with the incidence of APN during pregnancy, and these should be monitored closely during antenatal care.

Sarcomatoid chromophobe renal cell carcinoma revealed by acute pyelonephritis in a diabetic patient

Chromophobe renal cell carcinoma (CRCC) is a rare tumor comprising 2 types of cells (eosinophilic and clear cells), coexisting in varying proportions.

CRCC has an overall good prognosis. However, the rarely encountered sarcomatoid differentiation is associated with a pejorative outcome and must, therefore, be rigorously ruled out.

Acute pyelonephritis and other infectious complications rarely occur.

We report a case of CRCC with sarcomatoid differentiation in a woman in her sixties which was revealed by acute pyelonephritis and had a lethal outcome.

Clinical effectiveness of oral antimicrobial therapy for acute pyelonephritis caused by extended-spectrum β-lactamase-producing Enterobacteriales

Infections caused by extended-spectrum β-lactamase-producing Enterobacteriales (ESBL-PE) are commonly treated with intravenous antibiotics. This study investigated whether oral antimicrobial therapy (OAT) is as effective as intravenous antimicrobial therapy (IVT) for acute pyelonephritis (APN) caused by ESBL-PE. A retrospective cohort of patients with APN caused by ESBL-PE was studied at a tertiary-care hospital from January 2014 through December 2016. The OAT group comprised patients treated with an appropriate oral antimicrobial agent following 7 days or less of IVT. The primary endpoint was treatment failure defined as clinical and/or microbiological failure. The secondary endpoint was length of hospital stay and recurrences of APN within 2 months and within 1 year. Propensity score matching and multivariable Cox proportional hazard modeling were used to minimize bias. Among 238 eligible cases, Escherichia coli (83.6%) was the most common pathogen. Sixty patients received OAT after a median of four days of appropriate IVT, and 178 patients completed treatment with IVT. Fluoroquinolones (58.3%) were the most commonly prescribed OAT, followed by trimethoprim-sulfamethoxazole and amoxicillin-clavulanate. OAT was not associated with treatment failure (adjusted OR 0.66; 95% CI 0.18-2.44) and hospitalization length was shorter in the OAT group (6.2 days versus 10.7 days; P < 0.01). APN recurrence caused by ESBL-PE infection within 2 months was not associated with OAT (adjusted HR 0.56; 95% CI 0.16-2.00). OAT reduced hospital stay without adverse effects on treatment outcome. OAT could be safely applied as a carbapenem-saving option in treatment of APN.

Prevention of Renal Scarring in Acute Pyelonephritis by Probiotic Therapy: an Experimental Study

We evaluated the protective effects of probiotic administration as a prophylaxis treatment and immediately after fever onset in increasing the immune response and decreasing the renal scarring in a rat model of acute pyelonephritis. Twenty-four rats were apportioned to three groups. In GI (n = 8), the rats were injected with direct inoculation of Escherichia coli into the right kidney. In GII (n = 8), the rats received a probiotic regimen 1 month before E. coli injection and the probiotic regimen was continued for the next 2 months. In GIII (n = 8), the probiotic regimen was started just after E. coli injection and was continued for 2 months. Technetium-99m-DMSA renal scan, histopathological evaluations, concentrations of CA19-9, IgA, blood urea nitrogen (BUN), and creatinine were assessed 1 and 2 months post-injection. It took an average of 4.2 ± 1.1 h between the injection and onset of fever in GI and GII. In GIII, this period was longer (7.5 ± 1.4). Probiotic administration resulted in reduction of interstitial fibrosis and tubular and glomerular atrophy in GII in all follow-ups. Technetium-99m-DMSA renal scan showed that the right kidney reached near the normal cortical integrity (47%) in GII compared to GI (32%) after 2 months of injection. However, the renal integrity did not improve significantly in GIII (41%). In GII, CA19-9 was lower (p < 0.05), while the levels of serum and fecal IgA were higher (p < 0.05). Administration of the probiotic regimen in the rat model may decrease renal damage in pyelonephritis. In spite of better results in the prophylactic group compared to the treatment group, no strong evidence was found to prove the advantage of its prophylactic application over the treatment administration.

Trend of antibiotics usage for acute pyelonephritis in Korea based on national health insurance data 2010-2014

Background

The objective of this study is to describe the changes in prescribing practices of antibiotics to treat acute pyelonephritis (APN) in Korea.

Methods

The claim data base of the Health Insurance Review and Assessment Service in Korea was used to select patients with ICD-10 codes N10 (acute tubulo-interstitial nephritis) or N12 (tubulo-interstitial nephritis, not specified as acute nor chronic) as the primary discharge diagnosis during 2010–2014. Consumption of each class of antibiotics was converted to Defined Daily Dose (DDD)/event.

Results

Throughout the five-year period, the average antibiotic consumption were 11.3 DDD per inpatient event and 6.0 DDD per outpatient event. The annual average antibiotic consumption increased for inpatients (P = 0.002), but remained stable for outpatients (P = 0.066). The use of parenteral antibiotics increased for inpatients (P < 0.001), but decreased for outpatients (P = 0.017). As for the the antibiotic classes, 3^rd generation cephalosporins (3^rd CEPs) was the most commonly prescribed (41.4%) for inpatients, followed by fluoroquinolones (FQs) (28.5%); for outpatient, FQs (54.8%) was the most commonly prescribed, followed by 3^rd CEPs (13.1%). The use of 3^rd CEPs (P < 0.001), beta-lactam/beta-lactamase inhibitors (P = 0.007), and carbapenems (P < 0.001) increased substantially for the treatment of hospitalized APN patients. In particular, carbapenems use increased 3.1-fold over the 5 years.

Conclusions

Prescription of broad-spectrum antibiotics increased much for the treatment of APN in Korea during 2010–2014.

Serum soluble ST2 as a marker of renal scar in pediatric upper urinary tract infection

BACKGROUND AND OBJECTIVES

Upper urinary tract infection is the most common serious bacterial infection in childhood. Patients with upper urinary tract infection have a risk for renal scarring with subsequent complications including hypertension, proteinuria, and progressive renal failure. However, the predictive biomarkers of renal scarring in children with upper urinary tract infection are still unknown. In this study, we evaluated whether soluble ST2 levels can be biomarkers of subsequent renal scarring in patients with upper urinary tract infection.

DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS

We retrospectively studied pediatric patients with upper urinary tract infection at a tertiary center. Twenty-eight children had an upper urinary tract infection with (n = 14) and without (n = 14) renal scarring and underwent 99mtechnetium dimercaptosuccinic acid imaging. In addition, 13 control subjects were enrolled. The clinical data and serum cytokine levels, including soluble ST2 levels, were compared between those with and without renal scars.

RESULTS

Serum soluble ST2 levels were significantly higher in the scar group than in the non-scar group, whereas there was no difference in the levels of serum interferon-γ, interleukin-6, interleukin-10, soluble tumor necrosis factor receptor 1, and transforming growth factor-β between the scar and non-scar groups. The area under the curve for differentiating between the non-scar and scar groups on the basis of measurements of serum soluble ST2 was 0.79, with a sensitivity and specificity of 92.9% and 64.3%, respectively.

CONCLUSION

These results suggest that serum soluble ST2 levels on admission could be a useful biomarker of subsequent renal scarring in pediatric patients with upper urinary tract infection.

Inappropriate empirical antibiotic therapy does not adversely affect the clinical outcomes of patients with acute pyelonephritis caused by extended-spectrum β-lactamase-producing Enterobacteriales

Extended-spectrum β-lactamase-producing Enterobacteriales (ESBL-PE) are often associated with inappropriate empirical therapy (IAT). The aim of this study was to investigate whether IAT of acute pyelonephritis (APN) caused by ESBL-PE is related to adverse outcomes. A retrospective cohort study was performed at a tertiary-care hospital from 2014 through 2016. Patients who had APN caused by ESBL-PE and were definitely treated with appropriate antibiotics for at least 7 days were enrolled. IAT was defined as when inappropriate empirical antibiotics were given 48 h or longer after initial diagnosis of APN. Primary endpoint was treatment failure defined as clinical and/or microbiologic failure. Secondary endpoints were length of hospital stay and recurrence of APN. Propensity score matching was used to adjust heterogeneity of each group. Among 175 eligible cases, 59 patients received IAT and 116 patients received appropriate empirical antimicrobial therapy (AT). Treatment failure was observed in five (8.4%) patients and nine (7.8%) patients in each group, respectively. After matching, the treatment failure rate was similar between both groups (adjusted odd ratio [aOR] 1.05; 95% confidence index [CI] 0.26-4.15). The length of hospital stay (median 11 days in the IAT group versus 11 days in the AT group; P = 0.717) and absence of recurrence within 2 months (90.3% in IAT and 86.7% in AT; P = 0.642) were also similar. IAT did not adversely affect the clinical outcome. In this regard, clinicians should be more cautious about indiscriminate prescription of broad-spectrum antibiotics such as carbapenem empirically for treatment of APN possibly caused by ESBL-PE.

Factors associated with the recurrence of acute pyelonephritis caused by extended-spectrum β-lactamase-producing Escherichia coli: the importance of infectious disease consultation

To investigate factors for the recurrence of acute pyelonephritis (APN) caused by extended-spectrum β-lactamase-producing Escherichia coli (ESBL-PE), a retrospective cohort study was performed at a tertiary-care hospital from 2014 through 2016. Among 135 patients who had recovered from APN caused by ESBL-PE, the 1-year cumulative recurrence rates of APN caused by any pathogen or by ESBL-PE specifically were 35.6% and 22.1%, respectively. In a multivariate analysis, infectious disease (ID) consultation was associated with decreased recurrence (95% confidence interval [CI] = 0.24-0.96, P = 0.038 for recurrence caused by any pathogen; and 95% CI = 0.15-0.84, P = 0.019 for recurrence caused by ESBL-PE). History of APN within 1 year was a risk factor for recurrent APN caused by any pathogen (P = 0.011). Microbiological cure was a preventive factor for recurrent APN caused by ESBL-PE (P = 0.024). In conclusion, our data show that ID consultation protects against APN recurrence caused by ESBL-PE.

Infectious and Inflammatory Diseases of the Urinary Tract: Role of MR Imaging

Urinary tract infection (UTI) is among the most common of bacterial infections. Imaging studies are only required in cases of complicated UTIs. Ultrasound remains the first-line imaging method; however, CT is the gold standard for evaluation of UTIs. MR imaging's improved contrast resolution and absence of ionizing radiation may recommend its use for assessment of lower UTIs. Furthermore, MR imaging performs with diagnostic accuracy at least similar to CT in complicated UTIs, except for the identification of calculi and emphysematous pyelonephritis. In this article, the role of MR imaging for the evaluation of infectious and inflammatory disease processes of the urinary tract is reviewed.

Comparison between non-septic and septic cases in stone-related obstructive acute pyelonephritis and risk factors for septic shock: A multi-center retrospective study

PURPOSE

This study assessed risk factors for septic shock in patients with obstructive acute pyelonephritis (APN) associated with upper urinary tract calculi in a multi-center retrospective study.

METHODS

We studied 143 patients admitted to 4 hospitals in Japan with obstructive APN associated with upper urinary tract calculi. Data on gender, age, hypertension, diabetes, neurological disease or malignant disease, laboratory data (white blood cell (WBC) and C-reactive protein (CRP)), drainage, and bacterial strains including Escherichia coli in the non-septic and septic groups were collected. Risk factors for septic shock were analyzed by univariate and multivariate statistical analyses.

RESULTS

There were a total of 107 non-septic cases (74.8%) and 36 septic cases (25.2%). The commonest strains of urinary tract infection-causative bacteria were E. coli in the non-septic group (23 cases, 21.5%) and septic group (13 cases, 36.1%) (p > 0.05). Emergency drainage was administered in 74.8% of the non-septic group and 97.2% of the septic group (p > 0.05). Meropenem was most often used as the initial treatment in the non-septic group (20 cases, 18.7%) and septic group (22 cases, 61.1%) (p < 0.0001). Risk factors for septic shock in multivariate analyses were diabetic mellitus (odds ratio (OR) = 3.591, p = 0.0098) and CRP ≥ 10 (OR = 1.057, p = 0.0119) as significant independent factors in this multicenter study.

CONCLUSIONS

APN is a common infectious disease, especially in the cases with urinary tract obstruction where patients easily acquire bacteremia or sepsis. Stone-associated obstructed APN can cause fatal septic shock in cases with diabetes and CRP ≥ 10. Further prospective studies will be undertaken to draw definitive conclusions.

Acute pyelonephritis revealing an intraprostatic obstructive megaureter in an adult: A rare finding

•

Duplicated renal collecting system is one of the most common congenital upper urinary tract abnormalities.

•

Estimated prevalence ranges between 0.3–6% in the general population.

•

Duplex system with ectopic obstructive megaureter in the prostatic urethra is rare and exceptionally revealed in adulthood.

•

Although considered an anatomical variant, duplex collecting system may be complicated by vesicoureteral reflux, ureterocele, or ectopic ureter.

•

In case of complicated duplex collecting, the surgical treatment may include upper pole nephrectomy or total nephrectomy. For pediatric patients, nephron-saving surgery is recommended.

•

Early diagnosis and treatment of complicated duplex system is important.

Introduction

Duplicated renal collecting system is one of the most common congenital upper urinary tract abnormalities. Duplex system with ectopic obstructive megaureter in the prostatic urethra is rare and exceptionally revealed in adulthood.

Presentation of case

We present a rare case of a 72-year-old man without any previous history of urinary symptoms, admitted through the emergency department for altered general condition associated with fever for several days. Investigations have identified left complete duplex system and intraprostatic obstructive megaureter manifesting as acute pyelonephritis. The evolution of acute pyelonephritis was favorable under urine drainage by percutaneous nephrostomy tube and antibiotherapy.

Given the multiple comorbidities of the patient, radical surgical treatment by left upper pole nephrectomy was ruled out and we opted for an iterative change of percutaneous nephrostomy tube.

Discussion

We briefly review the pathophysiology, diagnosis and therapeutic aspects.

Conclusion

Early diagnosis and treatment of complicated duplex system is important. Urologists should keep this anomaly in mind.

Therapeutic effects of 5,2'-dibromo-2,4',5'-trihydroxydiphenylmethanone (LM49) in an experimental rat model of acute pyelonephritis by immunomodulation and anti-inflammation

Antibiotics are still the primary therapy for acute pyelonephritis (APN); rarely, natural polyphenols are also used. LM49 is a novel marine bromophenol derivative displaying strong anti-inflammatory effects. We investigated the therapeutic efficacy of LM49 in an experimental rat model of APN. The model was established by injecting 0.5 mL Escherichia coli (ATCC 25922, 10⁸ CFU/mL) into the urinary bladders of Sprague Dawley rats. This model showed increased kidney viscera indices and renal bacterial growth scores, as well as pathological changes in kidneys. We also performed a broth microdilution antimicrobial susceptibility test of the E. coli strain. Both norfloxacin and LM49 treatment reduced kidney viscera indices and decreased microbial counts in urine cultures and kidney homogenates in APN rats. However, in vitro experiments showed that LM49 did not directly inhibit bacteria. Rather, LM49 treatment inhibited inflammatory cell infiltration or abscess and improved tissue lesions in the renal medullary junction, renal pelvis, and calyx, and high-dose LM49 treatment inhibited the production of inflammatory interleukin-1β (IL-1β) and interleukin-6 (IL-6) in serum. CD4⁺ T cells were higher in the LM49 groups treated with high, medium, and low doses than in the model group, whereas only high-dose LM49 treatment increased the number of CD8⁺ T cells, as compared with that in the model group. However, LM49 treatment did not influence hematological parameters. Our results show that LM49 therapeutic effects in an APN animal model may be achieved by regulating immune responses and inhibiting inflammatory mediators, suggesting it as a candidate APN treatment.

Diffusion-weighted magnetic resonance imaging is more sensitive than dimercaptosuccinic acid scintigraphy in detecting parenchymal lesions in children with acute pyelonephritis: A prospective study

INTRODUCTION

Static renal scintigraphy is the gold standard for detection of inflammatory changes in the renal parenchyma in acute pyelonephritis. Our aim was to determine whether diffusion-weighted magnetic resonance imaging (DW-MRI) was comparable with static renal scintigraphy (DMSA-SRS) to demonstrate acute renal parenchymal lesions.

OBJECTIVE

To compare ^99mTc-dimercaptosuccinic acid static renal scintigraphy (DMSA-SRS) with diffusion-weighted magnetic resonance imaging (DW-MRI) for detecting acute inflammatory changes in the renal parenchyma in children with febrile urinary tract infection.

METHODS

Thirty-one children (30 girls) aged 3-18 years with a first episode of febrile UTI without a previously detected congenital malformation of the urinary tract, were prospectively included. DMSA-SRS and DW-MRI were performed within 5 days of diagnosis to detect renal inflammatory lesions. The DW-MRI examination was performed without contrast agent and without general anesthesia. Late examinations were performed after 6 months using both methods to detect late lesions.

RESULTS

DW-MRI confirmed acute inflammatory changes of the renal parenchyma in all 31 patients (100%), mostly unilateral. DMSA-SRS detected inflammatory lesions in 22 children (71%; p = 0.002). The lesions were multiple in 26/31 children (84%) on DW-MRI and in 9/22 (40%) on DMSA-SRS. At the control examination, scarring of the renal parenchyma was found equally by DW-MRI and DMSA-SRS in five patients (16%), three of whom were the same patients. The overall concordance of positive and negative late findings occurred in 87% of patients. There was correspondence in the anatomical location of acute and late lesions.

DISCUSSION

The clinical significance of acute and late parenchymal findings on DWI-MR is yet to be determined. A limitation of our study is the age of the patients (older than 3 years) who are less sensitive to scar development; therefore, a smaller number of patients with scars could be analyzed during control examination. Further studies using the DW-MRI should confirm its reliability to detect acute and late lesions in younger children and infants and determine the clinical consequences.

CONCLUSION

DW-MRI has higher sensitivity for detecting acute renal inflammatory lesions and multifocal lesions than DMSA-SRS. The incidence of scars was low and corresponded with the anatomical location of acute and late lesions.

Qualitative and quantitative radiological analysis of non-contrast CT is a strong indicator in patients with acute pyelonephritis

OBJECTIVE

To evaluate the performance of non-contrast computed tomography (CT) by reporting the difference in attenuation between normal and inflamed renal parenchyma in patients clinically diagnosed with acute pyelonephritis (APN).

MATERIAL AND METHODS

This is a retrospective study concerned with non-contrast CT evaluation of 74 patients, admitted with a clinical diagnosis of APN and failed to respond to 48h antibiotics treatment. Mean attenuation values in Hounsfield units (HU) were measured in the upper, middle and lower segments of the inflamed and the normal kidney of the same patient. Independent t-test was performed for statistical analysis. Image evaluation included receiver operating characteristic (ROC), visual grading characteristic (VGC) and kappa analyses.

RESULTS

The mean attenuation in the upper, middle and lower segments of the inflamed renal cortex was 32%, 25%, and 29% lower than the mean attenuation of the corresponding cortical segments of the contralateral normal kidney, respectively (p<0.01). The mean attenuation in the upper, middle, and lower segments of the inflamed renal medulla was 48%, 21%, and 30%, lower than the mean attenuation of the corresponding medullary segments of the contralateral normal kidney (p<0.02). The mean attenuation between the inflamed and non-inflamed renal cortex and medulla was 29% and 30% lower respectively (p<0.001). The AUCROC (p<0.001) analysis demonstrated significantly higher scores for pathology detection, irrespective of image quality, compared to clinical and laboratory results with an increased inter-reader agreement from poor to substantial.

CONCLUSION

Non-contrast CT showed a significant decrease in the parenchymal density of the kidney affected with APN in comparison to the contralateral normal kidney of the same patient. This can be incorporated in the diagnostic criteria of APN in NCCT in the emergency setting.

Selective imaging modalities after first pyelonephritis failed to identify significant urological anomalies, despite normal antenatal ultrasounds

AIM

We investigated the consequences of applying different imaging guidelines for urological anomalies after first pyelonephritis in children with normal routine antenatal ultrasounds.

METHODS

The cohort comprised 472 children treated for their first culture-positive pyelonephritis and investigated with ultrasound and renal scintigraphy. We excluded patients with known urological anomalies and patients born before routine antenatal ultrasound. We followed the cohort for a median of 5.7 years (3.1-10.1 years) by reviewing their medical reports.

RESULTS

Urological anomalies were diagnosed in 95 patients. Dilated vesicoureteral reflux (VUR) was the predominant finding (n = 29), including nine who initially had surgery. Using imaging guidelines from the American Academy of Pediatrics would have missed 11 urological patients, including two with initial surgery, and avoided 339 scintigraphies. Using the European Association of Paediatric Urology guidance would have missed three urological patients, one with initial surgery, and avoided 46 scintigraphies. Investigating patients under two years with ultrasound and scintigraphy, and just ultrasound in children over two years, would have identified all patients initially treated with surgery and avoided 65 scintigraphies.

CONCLUSION

Dilated VUR was the dominant anomaly in a cohort with first time pyelonephritis and normal antenatal ultrasound. The optimal imaging strategy after pyelonephritis must be identified.

New markers of urinary tract infection

Urinary tract infection (UTI) is the most common bacterial infection independent of age. It is also one of the most common causes of hospitalizations for infections among elderly people and the most common indication for antibiotic prescriptions in primary care. Both diagnostics and management of lower and upper urinary tract infections provide challenges in clinical practice due to their high prevalence and recurrence, and worldwide increase of antibiotic resistance. The clinical symptoms of UTI are often uncharacteristic or asymptomatic. The accurate diagnosis and early treatment are crucial due to risk of septicaemia and long-term consequences. Currently the diagnosis of urinary tract infection is based on the presence of clinical symptoms in combination with the results of nitrite strip test indicating the presence of bacteria in urine and semi-quantitative measurement of white blood cells count in urine. Although urine culture is the gold standard in UTI diagnostics it is both time-consuming and costly. Searching for novel biomarkers of UTI has attracted much attention in recent years. The article reviews several promising serum and urine biomarkers of UTI such as leukocyte esterase, C-reactive protein, procalcitonin, interleukins, elastase alpha (1)-proteinase inhibitor, lactofferin, secretory immunoglobulin A, heparin-binding protein, xanthine oxidase, myeloperoxidase, soluble triggering receptor expressed on myeloid cells-1, α-1 microglobulin (α1Mg) and tetrazolium nitroblue test (TNB).

[Molecular epidemiology and kinetics of early Escherichia coli urinary tract infections in kidney transplant recipients]

BACKGROUND

Escherichia coli strains causing Urinary Tract Infections (UTI) have a fecal origin.

METHODS

A fecal sample was collected before Kidney Transplantation (KT) and concomitantly with urine at each of the 15 E. coli UTIs which occurred in 11 KT recipients. Unique E. coli strains were identified among 25 isolates per feces and 5 isolates per urinary sample by random amplification of polymorphic DNA. Phylogenetic group (which is correlated to virulence in the E. coli species) was determined for each E. coli strain by a PCR based method.

RESULTS

Forty-three unique fecal strains and 14 unique urinary strains were identified among 650 fecal isolates and 75 urinary isolates. Urinary strains frequently (55% of the cases) belonged to a phylogroup usually not linked to virulence. They were detected in the feces collected concomitantly in 60% of the cases. Urinary strains belonging to a phylogroup usually linked to virulence were more frequently dominant in the feces (100%) than urinary strains belonging to a non-pathogenic phylogroup (42%; P<0.05). Vesical catheter was a facilitating factor only for urinary strains belonging to non-pathogenic phylogroups. Thirty-three percent of the fecal strains were persisting in two consecutive fecal samples and 62% were detected for the first time at the UTI. Numerous pathway lead to UTIs: from a unique, virulent and persisting strain to a non-virulent recently acquired strain facilitated by a vesical catheter.

CONCLUSION

Our work shows the diversity of host-microbial interactions which precede extra-intestinal virulence.

Serial sonographic findings during progression from acute pyelonephritis to renal abscess: a rare case report

Renal abscess, accumulation of infective fluid in the kidney, is a rare pathology. Currently, no reports of the serial imaging changes of acute pyelonephritis (APN) progressing to renal abscess exist. We report clinical and serial sonographic findings of a patient with hyper-immunoglobulin E syndrome, a primary immunodeficiency, who developed APN that progressed to renal abscess. Renal ultrasonography revealed that echogenicity of infectious lesions dramatically changed from isoechoic to hyperechoic and to hypoechoic during progression. These findings are useful for differential diagnosis of APN, acute focal bacterial nephritis, and renal abscess.

Plasma neutrophil gelatinase-associated lipocalin: a marker of acute pyelonephritis in children

OBJECTIVES

This study was designed to compare the diagnostic accuracy of plasma neutrophil gelatinase-associated lipocalin (NGAL) with procalcitonin (PCT), C-reactive protein (CRP), and white blood cells (WBCs) for predicting acute pyelonephritis (APN) in children with febrile urinary tract infections (UTIs).

MATERIALS AND METHODS

In total, 138 children with febrile UTIs (APN 59, lower UTI 79) were reviewed retrospectively. Levels of NGAL, PCT, CRP, and WBCs in blood were measured on admission. The diagnostic accuracy of the biomarkers was investigated. Independent predictors of APN were identified by multivariate logistic regression analysis.

RESULTS

Receiver operating curve (ROC) analyses showed good diagnostic profiles of NGAL, PCT, CRP, and WBCs for identifying APN [area under the curve (AUC) 0.893, 0.855, 0.879, and 0.654, respectively]. However, multivariate analysis revealed only plasma NGAL level was an independent predictor of APN (P = 0.006). At the best cutoff values of all examined biomarkers for identifying APN, sensitivity (86 %), specificity (85 %), positive predictive value (81 %), and negative predictive value (89 %) of plasma NGAL levels were the highest. The optimal NGAL cutoff value was 117 ng/ml. The positive likelihood ratio [odds ratio (OR) 5.69, 95 % confidence interval (CI) 3.56-8.78], and negative likelihood ratio (OR 0.16, 95 % CI 0.08-0.29) of plasma NGAL for APN diagnosis also showed it seemed to be more accurate than serum PCT, CRP, and WBCs.

CONCLUSION

Plasma NGAL can be more useful than serum PCT, CRP, and WBC levels for identifying APN in children with febrile UTIs.

Role of piperacillin/tazobactam as a carbapenem-sparing antibiotic for treatment of acute pyelonephritis due to extended-spectrum β-lactamase-producing Escherichia coli

Extended-spectrum β-lactamase-producing Escherichia coli (ESBL-Ec) is a frequent cause of acute pyelonephritis (APN), requiring carbapenem therapy. However, alternatives to carbapenems are needed due to the emergence of carbapenemase-producing micro-organisms. The purpose of this study was to compare the clinical efficacy of piperacillin/tazobactam (TZP) versus ertapenem in the treatment of adult patients with APN caused by ESBL-Ec. A retrospective observational study of APN caused by ESBL-Ec susceptible to TZP was performed at a university-affiliated hospital in the Republic of Korea between February 2011 and June 2013. All adult patients initially treated with in vitro-active TZP were compared with those treated with ertapenem to evaluate antibiotic clinical efficacy. The primary endpoint was treatment failure, defined as a composite of in-hospital mortality, change of initial antibiotic regimen and microbiological eradication failure. During the study period, 68 patients prescribed TZP and 82 patients prescribed ertapenem were eligible for inclusion in the study. There was no significant difference between the two treatment groups in the occurrence of in-hospital mortality, change of initial antibiotic regimen or microbiological eradication failure. In the multivariate analyses, predictors associated with treatment failure included septic shock [odds ratio (OR) = 4.27, 95% confidence interval (CI) 1.66-10.99] and recent administration of immunosuppressive agents (OR = 2.84, 95% CI 1.02-7.91). However, the type of antibiotic was not associated with treatment failure. TZP could be an effective alternative to ertapenem for the treatment of APN caused by ESBL-Ec, sparing carbapenem consumption in the multidrug-resistant era.

Delayed treatment of the first febrile urinary tract infection in early childhood increased the risk of renal scarring

AIM

This study evaluated the controversial relationship between the duration of fever before treatment initiation (FBT) for a febrile urinary tract infection (UTI), with renal scarring based on dimercaptosuccinic acid scintigraphy (DMSA) findings.

METHODS

The inpatient records of 148 children under two years of age with a first episode of febrile UTI were analysed. Acute and repeat DMSA findings, and clinical and laboratory parameters were evaluated.

RESULTS

Acute DMSA showed that 76 of the 148 children with a febrile UTI had renal lesions: 20 were mild, and 56 were moderate or severe. Repeat DMSA showed renal scarring in 34 patients. The only factors associated with the development of renal scars in the repeat DMSA were FBT of more than 72 hours, the presence and severity of vesicoureteral reflux and increased procalcitonin levels and absolute neutrophil counts. Multiple regression analysis showed that an FBT above 72 hours was the only significant factor that predicted renal scars.

CONCLUSION

Delay in treatment initiation of 72 hours or more was a risk factor for permanent renal scars after the first episode of febrile UTI. Other associated factors were increased procalcitonin and absolute neutrophil count on admission and the presence and severity of vesicouretal reflux.

Core curriculum illustration: acute pyelonephritis

This is the 26th installment of a series that will highlight one case per publication issue from the bank of cases available online as part of the American Society of Emergency Radiology (ASER) educational resources. Our goal is to generate more interest in and use of our online materials. To view more cases online please visit the ASER Core Curriculum and Recommendations for Study online at: http://www.aseronline.org/curriculum/toc.htm .