Prevalence of renal anomalies after urinary tract infections in hospitalized infants less than 2 months of age

Urinary tract infections in very premature neonates: the definition dilemma

BACKGROUND AND OBJECTIVES

Data on urinary tract infections (UTIs) in very preterm neonates (VPTNs) are scarce. We aimed to (i) describe the characteristics of UTIs in VPTNs and (ii) compare the diagnostic practices of neonatal clinicians to established pediatric guidelines.

METHODS

All VPTNs (<29 weeks GA) with a suspected UTI at the CHU Sainte-Justine neonatal intensive care unit from January 1, 2014, and December 31, 2019, were included and divided into two definition categories: Possible UTI, and Definite UTI.

RESULTS

Most episodes were Possible UTI (87%). Symptoms of UTIs and pathogens varied based on the definition category. A positive urinalysis was obtained in 25%. Possible UTI episodes grew 2 organisms in 62% of cases and <50,000 CFU/mL in 62% of cases.

CONCLUSION

Characteristics of UTIs in VPTNs vary based on the definition category and case definitions used by clinicians differ from that of established pediatric guidelines.

Urinary Tract Infection Epidemiology in NICUs in the United States

OBJECTIVE

Our objective was to characterize the incidence, associated clinical factors, timing of infection, microbiology, and incidence of concordant blood culture of urinary tract infections (UTIs) in very low birth weight (VLBW <1,500g) infants.

STUDY DESIGN

Multicenter observational cohort study of VLBW infants with gestational age (GA) ≤32 weeks, still hospitalized on postnatal day 7, and discharged 2010 to 2018 from Pediatrix Medical Group neonatal intensive care units. Demographic and clinical characteristics of infants with and without UTI were compared. Multivariable logistic regression evaluated adjusted odds of UTI diagnosis.

RESULTS

Of 86,492 included infants, 5,988 (7%) had a UTI. The most common pathogen was Enterococcus spp. (20%), followed by Escherichia coli (19%) and Klebsiella spp. (18%). Candida spp. (6%) was the most common nonbacterial pathogen. Concordant-positive blood culture was present in 8% of infants with UTI diagnoses. UTI was associated with lower GA, male sex, vaginal delivery, prenatal steroid exposure, and longer duration of hospitalization.

CONCLUSION

UTI is a common cause of infection in VLBW infants, especially among the smallest, most premature, male infants, and those with a longer duration of hospitalization. Neonatal clinicians should consider obtaining urine culture in the setting of late-onset sepsis evaluations in VLBW infants.

KEY POINTS

· UTI is a common cause of LOS in VLBW infants.. · The most common pathogens are Enterococcus spp. and E. coli.. · UTI risk varies among different VLBW infant populations.. · Next steps should include evaluation of preventative measures..

Epidemiologic, microbiologic and imaging characteristics of urinary tract infections in hospitalized children < 2 years of age diagnosed with anatomic abnormalities of the urinary tract

BACKGROUND

To compare the epidemiologic, microbiologic and imaging characteristics of urinary tract infections (UTI) in children <2 years of age with and without anatomic urinary tract abnormalities (AA).

METHODS

All children hospitalized with UTI during 1.1.2005-31.12.2018 were included. The study group (patients with AA) included 76 patients. The control group (99 patients) included patients without AA.

RESULTS

1163 children were hospitalized. Age at diagnosis was younger in the study group vs. controls (5.2 ± 6.0 vs. 7.9 ± 7.5 months, P = 0.038). Uropathogens distribution was different (P = 0.007), with lower Escherichia coli (Ec) and Proteus mirabilis (Pm) percentages in the study group and higher percentages of Enterococcus spp. (Ent) in controls. In the study group, Ec nonsusceptibility rates to ampicillin, amoxicillin/clavulanic acid, cefazolin, cefuroxime, TMP/SMX and ceftriaxone were 58%, 40%, 14%, 14%, 12% and 10%, respectively, with no differences vs. controls. Ultrasound (US) was performed in 69/76 (98%) patients with AA (84.1%, abnormal); bilateral (39.7%) and unilateral (32.7%) ureteral dilatation were the most frequent findings. Voiding cystourethrography was performed in 46 patients (pathologic in 35, 76%); 31 (81.6%) patients had vesicoureteral reflux (VUR) (bilateral in 11, 35.5%; grade 4/5 in 7 patients). Uropathogens distribution in VUR patients differed between study and control groups, with lower Ec and Pm in the first group and higher Pseudomonas aeruginosa and Ent percentages in the control group.

CONCLUSION

Age at diagnosis was lower and pathogen distribution was different in patients with AA. Antibiotic susceptibility patterns of the main uropathogens were similar between patients with or without AA.

Practice Summary of Antimicrobial Therapy for Commonly Encountered Conditions in the Neonatal Intensive Care Unit: A Canadian Perspective

Neonates are highly susceptible to infections owing to their immature cellular and humoral immune functions, as well the need for invasive devices. There is a wide practice variation in the choice and duration of antimicrobial treatment, even for relatively common conditions in the NICU, attributed to the lack of evidence-based guidelines. Early decisive treatment with broad-spectrum antimicrobials is the preferred clinical choice for treating sick infants with possible bacterial infection. Prolonged antimicrobial exposure among infants without clear indications has been associated with adverse neonatal outcomes and increased drug resistance. Herein, we review and summarize the best practices from the existing literature regarding antimicrobial use in commonly encountered conditions in neonates.

Infection control and other stewardship strategies in late onset sepsis, necrotizing enterocolitis, and localized infection in the neonatal intensive care unit

Suspected or proven late onset sepsis, necrotizing enterocolitis, urinary tract infections, and ventilator associated pneumonia occurring after the first postnatal days contribute significantly to the total antibiotic exposures in neonatal intensive care units. The variability in definitions and diagnostic criteria in these conditions lead to unnecessary antibiotic use. The length of treatment and choice of antimicrobial agents for presumed and proven episodes also vary among centers due to a lack of supportive evidence and guidelines. Implementation of robust antibiotic stewardship programs can encourage compliance with appropriate dosages and narrow-spectrum regimens.

Urinary tract infections in children < 2 years of age hospitalized in a tertiary medical center in Southern Israel: epidemiologic, imaging, and microbiologic characteristics of first episode in life

The objectives of the study were to describe the epidemiologic, microbiologic, and imaging characteristics of first 44 UTI episode in hospitalized infants and children < 2 years of age. A UTI episode was diagnosed based on suprapubic aspiration or urinary catheterization and report of a significant bacterial growth of true uropathogens. Two thousand two hundred ninety-four UTI episodes were recorded during 2009-2013 in 1694 patients; 1350 (79.7%), 223 (13.2%), and 66 (3.9%) had one, two, and three episodes, respectively. Of 1955 pathogens isolated, the most frequent were E. coli, Klebsiella spp., and Enterococcus spp. (56.9%, 14.1%, and 11%, respectively). E. coli percentages increased with increase in patient age while Klebsiella spp. and Enterococcus spp. decreased with decrease in age. 136/344 (39.5%) renal ultrasound examinations performed were reported abnormal. The percentages of abnormal ultrasound examinations in Enterococcus spp.-UTI were higher than in E. coli and Klebsiella spp.-UTI (P < 0.001 and P = 0.007, respectively). The E. coli nonsusceptibility to ampicillin, TMP/SMX, ceftriaxone, amoxicillin/clavulanic acid, cefuroxime, and gentamicin was 71%, 31%, 14.9%, 14.7%, 7%, and 4.4%, respectively. Nonsusceptibility of Klebsiella spp. to ampicillin, amoxicillin/clavulanic acid, TMP/SMX, ceftriaxone, gentamicin, and cefuroxime was 98.7%, 10.4%, 9.5%, 8.4%, 4.8%, and 4.3%, respectively. E. coli nonsusceptibility to amoxicillin/clavulanate, TMP/SMX, and ciprofloxacin decreased during the study period. E. coli percentages increased and those of Klebsiella spp. and Enterococcus spp. decreased with increase in patient age. Enterococcus. spp.-UTI was associated with older age and more severe findings on renal ultrasound. E. coli and Klebsiella spp. nonsusceptibility to amoxicillin/clavulanate, TMP/SMX, cefuroxime, and ceftriaxone was low.

Late-onset sepsis due to urinary tract infection in very preterm neonates is not uncommon

Urinary tract infection (UTI) is a common cause of sepsis in infants. Premature infants hospitalized at a neonatal intensive care unit often have risk factors for infection. In this group, the risk of UTI is not clearly known, and guidelines for urine analysis are not unanimous. We aimed to identify the risk of UTI in premature infants with central lines, suspected of late-onset sepsis. We analyzed all 1402 infants admitted to our hospital between 2006 and 2014 with a gestational age less than 32 weeks. Six hundred sixty-two episodes of sepsis evaluations were found with an unknown source of infection based on clinical symptoms. In half of this group, urine analysis was performed identifying UTI in 11.3% (24/212). In 13 of these infants (54%) with a UTI, infection was due to Candida albicans. In at least four episodes, the diagnosis and treatment would have been delayed if urine analysis had not been performed.

CONCLUSION

Based on these findings, we conclude that in premature infants with central lines, urine analysis should be performed routinely when signs of infection occur beyond 72 h after birth. Urine collection should not be delayed and cultures should preferably be performed before the start of the antibiotic treatment. What is known: • In preterm infants, the presence of other risk factors for infection might make clinicians reluctant to obtain urine cultures during sepsis evaluation. • An internal survey demonstrated that there is no consensus within the NICUs in The Netherlands regarding urine analysis as part of LOS work-up. What is new: • The risk of UTI in the NICU population (11.3%) is comparable to term infants; therefore, urine analysis should be performed routinely when LOS is suspected. • Candida albicans was the most frequently (54%) detected pathogen causing UTI in this population.

Incidence and risk factors of urinary tract infection in very low birth weight infants

OBJECTIVES

To describe the incidence and associated risk factors of urinary tract infection (UTI) in very low birth weight (VLBW) infants and to determine the value of diagnostic imaging studies after the first UTI episode before discharge from the neonatal intensive care unit (NICU).

METHODS

VLBW infants born during 2003-2012 were reviewed for UTI. In a nested case-control study, potential risk factors of UTI were compared between infants with UTI (cases) versus birth weight and gestational age matched controls. Renal ultrasonography (USG) and voiding cystourethrography (VCUG) results were reviewed in cases.

RESULTS

During the study period, 54.7% of urine culture specimens were collected by sterile methods. 3% (45/1,495) of VLBW infants met the study definition for UTI. UTI was diagnosed at mean postnatal age of 33.1±22.9 days. There was no significant difference in gender, ethnicity, antenatal steroid exposure, blood culture positive sepsis, ionotropic support, respiratory support and enteral feeding practices between cases and controls. Cases had a significantly higher cholestasis compared to controls (22% vs. 9% ; p = 0.03). However, cholestasis was not a significant predictor of UTI in the adjusted analysis [adjusted OR 2.38 (95% CI 0.84 to 6.80), p = 0.11]. Cases had higher central line days, parenteral nutrition days, total mechanical ventilation days, chronic lung disease, and length of stay compared to controls. Renal USG was abnormal in 37% and VCUG was abnormal in 17% of cases.

CONCLUSIONS

The incidence of UTI in contemporary VLBW infants is relatively low compared to previous decades. Since no significant UTI predictors could be identified, urine culture by sterile methods is the only reliable way to exclude UTI. The majority of infants with UTI have normal renal anatomy. UTI in VLBW infants is associated with increased morbidity and length of stay.

Prevalence of upper urinary tract anomalies in hospitalized premature infants with urinary tract infection

OBJECTIVE

The 2011 American Academy of Pediatrics (AAP) guidelines address imaging after initial febrile urinary tract infection (UTI) in infants >2 months of age. We sought to determine the frequency of upper urinary tract anomalies (hydronephrosis and vesicoureteral reflux (VUR)) in hospitalized premature infants with UTI.

STUDY DESIGN

We retrospectively reviewed the electronic medical records of neonatal intensive care unit (NICU) admissions at a tertiary care children's hospital between 1 January 2006 and 31 December 2010. We queried the records for UTI, renal ultrasound (US) and voiding cystourethrogram (VCUG).

RESULT

We identified 3518 unique admissions. UTI occurred in 118 infants (3%). Sixty-nine (60%) had a normal US. Renal dilation was predominantly renal pelvic dilation (12%) and isolated caliectasis (22%). VUR was identified in 15 (14%) infants evaluated with a VCUG. VUR was identified in nine (12%) infants without and in seven (16%) with an abnormality on US. Reflux was identified in 7% of male and 38% of female infants with a UTI.

CONCLUSION

Anatomic abnormalities of the upper urinary tract are uncommon in premature infants with a UTI that occurs during neonatal hospitalization. In concordance with the AAP guidelines, a VCUG may not be required in all NICU infants under age 2 months after a single UTI.

Urinary tract infections in the infant

Urinary tract infection (UTI) in an infant may be the first indication of an underlying renal disorder. Early recognition and initiation of adequate therapy for UTI is important to reduce the risk of long-term renal scarring. Ampicillin and gentamicin are traditionally the empiric treatment of choice; however, local antibiotic resistance patterns should be considered. Maternal antibiotics during pregnancy also increase the risk of resistant pathogens during neonatal UTI. Long-term management after the first UTI in infants remains controversial because of lack of specific studies in this age group and the risk-benefit issues for antibiotic prophylaxis between reduced recurrent disease and emergent antibiotic resistance.

Diagnosis and management of urinary tract infection and vesicoureteral reflux in the neonate

Urinary tract infection (UTI) is the most common bacterial infection in febrile newborns, particularly those born prematurely and with a low birth weight. Vesicoureteral reflux (VUR) predisposes to UTI and renal scarring. Half of neonates with UTI may have only low-grade fever or no fever. Jaundice in the absence of any other symptoms or signs may be the only clinical manifestation of UTI in neonates. The urinalysis may be negative in a significant number of neonates with UTI. Newborns with UTI have a high incidence of congenital anomalies of kidney and urinary tract anomalies, and hence should undergo renal imaging.

Group B Streptococcus and Escherichia coli infections in the intensive care nursery in the era of intrapartum antibiotic prophylaxis

BACKGROUND

Group B Streptococcus (GBS) and Escherichia coli cause serious bacterial infections (SBIs) and are associated with morbidity and mortality in newborn infants. Intrapartum antibiotic prophylaxis reduces early-onset SBIs caused by GBS. The effect of intrapartum antibiotic prophylaxis on late-onset SBIs caused by these organisms is unknown.

METHODS

We examined all blood, urine and cerebrospinal fluid culture results from infants admitted from 1997 to 2010 to 322 neonatal intensive care units managed by the Pediatrix Medical Group. We identified infants with positive cultures for GBS or E. coli and compared the incidence of early- and late-onset SBI for each organism in the time period before (1997 to 2001) and after (2002 to 2010) universal intrapartum antibiotic prophylaxis recommendations.

RESULTS

We identified 716,407 infants with cultures, 2520 (0.4%) with cultures positive for GBS and 2476 (0.3%) with cultures positive for E. coli. The incidence of GBS early-onset SBI decreased between 1997 to 2001 and 2002 to 2010 from 3.5 to 2.6 per 1000 admissions, and the incidence for E. coli early-onset SBI remained stable (1.4/1000 admissions in both time periods). Over the same time period, the incidence of GBS late-onset SBI increased from 0.8 to 1.1 per 1000 admissions, and incidence of E. coli late-onset SBI increased from 2.2 to 2.5 per 1000 admissions.

CONCLUSIONS

In our cohort, the incidence of GBS early-onset SBI decreased, whereas the incidence of late-onset SBI for E. coli and GBS increased.