Expert Commentary & Five-year View
The Issue of Long-term Sequelae of UTI
The concept that UTIs are responsible for scarring with long-term consequences has been challenged over the last decade,[4,5] and the new generation of guidelines focus rather on prompt diagnosis and effective treatment than on invasive and long-term interventions, such as extensive imaging and antibiotic prophylaxis. The latter remain controversial issues in the management of childhood UTI, but their extensive discussion was beyond the scope of this review. Agreement has been achieved on many aspects of diagnosis and treatment, but there are still questions that require further clarification.
The Issue of When to Suspect a UTI
Despite the attempts to set the index of suspicion more precisely – that is, to define criteria about which children to test – there are no satisfactory answers yet. We can only identify some of the acutely unwell young children with a very low probability of UTI – that is, circumcised boys >12 months – which in many parts of the world are exceptional. Thus, a low threshold for urine testing should better be kept for all febrile infants and young children without an apparent source of fever. Simple and valid clinical algorithms are expected with the completion of currently running prospective studies.
The Issue of the Urine Culture Interpretation
The 2011 AAP guideline set new criteria for the diagnosis of UTI in children aged <2 years with reduction of the culture positivity cutoff and inclusion of pyuria, emphasizing that urine should be obtained either by a bladder puncture or by catheterization. Whether the new criteria will be adopted, given that the previous ones hold for more than 50 years, or whether they will achieve their aim to reduce overdiagnosis remains to be answered; meanwhile, they trigger new questions. Should the new culture positivity cutoff be applied for catheter and SPA specimens as well, or just for voiding specimens, which are anyway not considered to be the optimal ones for this age? The answer probably lies in the previous AAP guideline and since this point has not been revised, any Gram-negative growth presumably remains the positivity cutoff for suprapubic specimens. On the other hand, the NICE, Italian and RCH Melbourne guidelines[13,101,102] consider clean catch as the preferable method of urine collection and either do not refer at all on culture positivity cutoffs (NICE guideline) or use different criteria (Italian and RCH Melbourne guidelines). This uncertainty leaves room for more subjective diagnosis and should be clarified by future research.
The Issue of Asymptomatic Bacteriuria
Infants with ABU are subject to overtreatment at the clinical level and a major confounding factor in research. This is particularly the case when these infants present with fever of a different origin. The use of additional diagnostic tests that are eaily applicable in clinic practice, such as CRP and PCT, would facilitate the correct diagnosis in this group. The NICE guidelines emphasize the identification of high-risk patients with complicated UTIs, describing some of their characteristics. Novel, noninvasive diagnostic tools such as urine IL-6 and IL-8 are expected to contribute in more accurate characterization of categories within the UTI patients in the years to come.
Issues of Antibiotic Treatment
The optimal mode and duration of treatment was for a long time controversial. Recent guidelines favor in general oral antibiotics either for the total course of therapy or after a short initial parenteral course, even for very young infants. Cost reduction is largely behind this practice. Although most children can be safely treated orally, it should be emphasized that the safety of oral treatment has not been adequately documented for neonates. This age group has often been excluded from studies, thus its particular characteristics have not been fully understood. Appropriately designed studies and evidence-based guidelines for the management of neonatal UTIs are obviously required. A similar cautious approach is advisable for the very young infants. Antibiotic selection depends on resistance patterns in a given region or institution. The increasing resistance rates of uropathogens call for judicious use of broad-spectrum agents, step-down adjustment of treatment when susceptibility results are available and continuous surveillance.
Issues of Adjunct Therapy
Antibiotics remain the cornerstone of treatment for childhood UTIs, and their proven efficacy has limited any interest for other therapeutic approaches in the past. This attitude has recently changed and adjunctive treatments to antiobiotics, such as steroids, have emerged, based on the gathered knowledge on host–pathogen interaction in the context of UTI. The clinical usefulness of these adjunct therapies is to be tested in the years to come.
The newer approach of the management of childhood febrile UTI questions the UTI-associated long-term morbidity and calls for less aggressive treatment and investigation, but remains alert for prompt diagnosis and watchful for efficient infection elimination. Challenges for the near future would include the implementation of new, simpler diagnostic tools, the establishment of the optimal antibiotic regimen according to patient or patient group and the application of adjunctive treatments in the face of strict and cost-driven health administrative policies. These practices will bring us to the next generation of guidelines, which would include identification of individual patient risk factors, bacterial virulence factors and consideration of host response parameters. The history of management of childhood UTI, for more than half a century now, has moved from careful gathering of evidence to controversy and aggressive practices[3,77–82] and then to a more selective approach and the search for consensus (Table 5). This long history of controversies suggests that it might take more than a few years to reach a patient-tailored approach; however, the news in the field seems to be the accelerated speed of aquisition of current knowledge, and the increasing trend for joint efforts by involved medical specialists, groups and societies.
Expert Rev Anti Infect Ther. 2012;10(10):1153-1164. © 2012 Expert Reviews Ltd.