Background: Extended-spectrum β-lactamase (ESBL)-producing pathogens are common among adults and are associated with extended and multiple hospitalizations. They cause urinary tract infections (UTIs) among children with known risk factors such as urinary tract abnormalities and antimicrobial prophylaxis. The emergence of UTIs caused by ESBL-producing organisms among infants has not been well characterized. Objective: We sought to describe the incidence and current clinical management of infants who were diagnosed with UTIs caused by ESBL-producing organisms at a pediatric emergency department (ED). In addition, we sought to describe risk factors associated with inpatient hospitalization for UTIs caused by ESBL-producing organisms. Methods: We retrospectively identified infants who were treated in the ED from 2013 to 2017 and who had positive urinalyses and urine cultures positive for greater than 50,000 colony-forming unit per milliliter of a single ESBL-producing urinary pathogen. We abstracted details of clinical management and known previous risk factors, including prior neonatal intensive care unit hospitalization stay, prior UTI caused by an ESBL-producing organism, and known urologic abnormalities. Results: Forty-five UTIs caused by ESBL-producing organisms occurred in 43 patients (mean age of 5.9 months and 59% female)—ESBL Escherichia coli represented the majority (42/45). The incidence of UTIs caused by ESBL-producing organisms ranged from 0.9% to 4.5% during the 5-year study period. The 13 patients (26%) admitted from the ED were significantly younger than discharged patients (1.9 vs 6.7 months, P = 0.016) and more likely to have had prior neonatal intensive care unit hospitalizations (50% vs 15.6%, P = 0.0456). Of the 33 visits (77%) resulting in initial outpatient management, 5 were followed by readmission for parenteral antibiotic treatment. Of those who were readmitted, 40% (n = 2) were afebrile at the time of admission. The remainder (28/33) completed outpatient oral antibiotic courses guided by susceptibilities. Two patients (4%) had negative repeat urine cultures despite in vitro resistance to initial antibiotic coverage. Conclusions: Extended spectrum β-lactamase–producing organisms are an increasing cause of UTIs in infants presenting at a pediatric ED, and outpatient management may be reasonable for infants older than 2 months.

Background: Due to the varied symptomatology and inconsistent features on neurologic exam, central nervous system (CNS) tumors are difficult to diagnosis in a timely manner. Objective: To determine the clinical, neurological, and neuroimaging features of newly diagnosed CNS tumors presenting to the emergency department (ED). Methods: We evaluated a retrospective cohort of 121 consecutive patients presenting to a tertiary care pediatric ED over 7 consecutive years with newly diagnosed CNS tumors. Clinical symptomatology, neurologic findings reported by emergency room and neurology physicians, neuroimaging features, and time to diagnosis were analyzed. Results: A total of 116 (48 female, median age 8.0 years (interquartile range, 4.4–12.6), 52% Hispanic) presented to the ED (64% self-referred) diagnosed with a brain tumor (54% posterior fossa, 24% embryonal, 24% low-grade glioma, 16% high-grade glioma) resulting in hospital admission in 92% of cases. Five were diagnosed with extradural spinal, clivus, or orbital apex tumors. Symptomatology or duration did not differ when stratified by demographics, location, or histologic subtype. Moderate degree of concordance was observed among neurologic examinations performed by ED physicians and neurologists. Delayed diagnosis (median delay = 3.5 [1–7] months) was seen in 14% of patients, 13 with primary brain tumors (11 hemispheric, 2 brain stem). Six children with delayed diagnosis of low-grade glial tumors had a nonfocal neurologic examination in comparison to 5 patients with abnormal examinations observed with primary spinal or extradural CNS tumors. Four patients with posterior fossa tumors (3 medulloblastoma, 1 ependymoma) had normal/near normal neurologic examination at presentation despite posterior fossa symptomatology related to increased intracranial pressure. Conclusions: Our series highlights the complexity of symptomology and neurologic findings in children presenting to the ED with newly diagnosed CNS tumors who may have a normal neurologic examination. Standardization of symptom assessment and focused neurologic examinations may lead to earlier neuroimaging and prevent delayed diagnosis.

Urinary tract infections (UTIs) are common in children and are predominantly caused by uropathogenic Escherichia coli (UPEC). An increasing proportion of these strains produce extended-spectrum β-lactamases (ESBLs), which render β-lactam antibiotics ineffective. Interestingly, some patients with ESBL-producing UTIs improve clinically following treatment with antibiotics like cephalexin, despite demonstrated in vitro resistance. Working alongside and at times synergistically with antibiotics, host immune factors, such as the antimicrobial peptide cathelicidin (LL-37), contribute to bacterial clearance through direct killing and inhibition of biofilm formation. In this review, we summarize the current understanding of pediatric ESBL-producing UPEC infections and present selected in vitro and in vivo experimental data evaluating the combined effects of LL-37 and cephalexin on clinical isolates. Although no synergy was observed, ESBL-producing isolates demonstrated reduced bacterial burden in vivo compared to a non-ESBL UPEC strain. These findings suggest that host immune factors and environmental conditions may influence the fitness and virulence of drug-resistant UTI pathogens, warranting further investigation.