SN Wong, wky Chan, S Chim, WM Lai, LCK Leung, NKC Tse

Abstract

The concept and management of urinary tract infection in children has been evolving over the past decades. While previous guidelines advocated universal imaging and antibiotic prophylaxis for young children with first time urinary tract infection (UTI), the recent guideline issued by the National Institute for Health and Clinical Excellence in the United Kingdom in August 2007 recommended a more selective strategy. This article presents a summary of the NICE Guideline with comments and recommendations by the authors. The Guideline was stringently developed and has incorporated recent scientific findings. Compared to previous guidelines, the major changes include the following: Firstly, it presents a complex algorithm for the diagnosis of UTI by rapid bedside tests. Diagnosis does not require urine culture in children above 3 years old who show positive dipstix results. Secondly it adopts a selective imaging strategy after first UTI. Ultrasound was recommended for infants below 6 months, or children of any age with atypical or recurrent UTI. Dimercapto-succinic acid scan was recommended for infants below 3 years with atypical or recurrent UTI, and those above 3 years with recurrent UTI. Micturiting cystourethrogram was recommended only for infants below 6 months with atypical or recurrent UTI or with abnormal ultrasound, and for infants above 6 months with atypical or recurrent UTI AND a family history of vesicoureteral reflux (VUR), poor urine stream, non-E.coli infection, or dilated renal pelves. Thirdly, antibiotic prophylaxis or surgery was not recommended routinely for VUR treatment. The authors discuss several concerns and suggest the following modifications for local practice: that a pre-treatment urine culture is useful in treatment by identifying the pathogen and its antibiotic sensitivity; that an ultrasound scan is reasonable, if a patient has not had a reliable antenatal or postnatal ultrasound, to exclude obstructive uropathies. For imaging strategy after a first UTI, the NICE Guideline is a reasonable approach if parents accept the small possibility of missing severe VUR for which the optimal treatment is still undecided. Until further evidence is available, a prudent option is to continue full imaging for infants below 12 months old and recommend antibiotics prophylaxis for Grade IV-V VUR. Further research is needed to better define the best treatment for severe VUR and to devise an investigation strategy that can identify those patients who may benefit from early detection of VUR and its treatment, and at the same time avoid over-investigating and over-treating the remaining patients.

近幾十年來，人們對於兒童尿路感染的認識以及治療水平在不斷得到改進與提高。既往的治療指南提倡對於首次診斷尿路感染（UTI）的兒童需要進行普遍的影像檢查以及抗生素預防性治療。最近，英國NICE在2007年 8月發佈的最新指南則推薦了另外一種可供選擇的診斷治療方案。本文將概要地介紹NICE指南中作者的相關觀點以及建議。該指南在經過嚴格完善發展的同時也不斷在將新近的科學發現加以了補充與整合。對比以前的指南，該指南主要的不同之處有：首先，它對於快速床邊檢測診斷UTI提供了一個複雜的法則體系。對於尿試紙實驗陽性的3歲以上兒童診斷UTI不需要進行尿培養檢查。其次，指南還提出了在首次發現UTI之後可使用一種根據不同情况供選擇的影像學檢查策略。超聲學檢查法推薦用於6個月以下的嬰兒以及復發或非典型性UTI病例的任何年齡兒童。DMSA 掃描法推薦用於3歲以下非典型或復發UTI的嬰兒以及那些3歲以上復發UTI的兒童。MCUG 僅推薦用於6個月以下的非典型或復發或USG異常的患UTI的嬰兒；6個月以上非典型或復發UTI 同時伴有膀胱輸尿管返流（VUR）、排尿困難、非大腸杆菌性尿路感染或腎盂擴張家族史的兒童。第三，指南並不推薦常規性使用抗生素預防以及進行外科手術來治療VUR。作者在經過討論及研究後，還考慮到不同局部地區的具體情况而對治療方面進行了一些調整與修改，它建議：治療前的尿培養的檢查可明確病原以及抗生素敏感性從而進一步為治療提供有益的幫助；如果病人在出生前或產後未進行可靠的超聲檢查，可進行超聲檢查以除外梗阻性尿路疾病。若患兒的父母能够接受錯過發現嚴重VUR（尚無明確治療方法）的極小可能性的話， NICE 指南對於首次診斷UTI的患兒提供了合理的影像學檢查方案。當前的謹慎的觀點是直到發現進一步的證據之前，要持續對12個月以下的嬰兒進行完整、充份的影像學檢查以及同時建議對於IV-V級VUR的患兒使用抗生素預防性治療。目前，仍需要更進一步的研究來幫助建立針對嚴重VUR的最佳治療方法以及設計一種可以早期發現VUR的檢查方案從而在使此類病人能够得到及時治療的同時也避免了對其他病人的過度檢查與治療。