Neri Danniele Almeida, Venturini Bruna Afonso, Massuqueto Eliakim, Estevam de Abreu Glícia, Portugal Matheus Mascarenhas, Costa Juliana, Velame Souza Santos Maria Karolina, de Araújo Rosier Catarina, Monteiro Gabriel, Barroso Ubirajara
Center for Childhood Urinary Disorders (CEDIMI), Salvador, Bahia, Brazil.
Center for Childhood Urinary Disorders (CEDIMI), Salvador, Bahia, Brazil.
J Pediatr Urol. 2025 Apr;21(2):296-302. doi: 10.1016/j.jpurol.2024.08.020. Epub 2024 Sep 3.
Uroflowmetry is a non-invasive examination considered as a first-line assessment for children with lower urinary tract symptoms (LUTS). Currently, the performance of two uroflowmetry tests is recommended by ICCS for all patients with LUTS. This study aims to evaluate the differences between two uroflowmetry tests in children with lower urinary tract symptoms and their impact on the patient's diagnostic workup and clinical outcome.
Forty patients with LUTS, aged 4-17 years, were evaluated prospectively with two consecutive uroflowmetry tests and ultrasonography. They were classified based on the ICCS criteria for curve pattern and divided into two groups based on the SPU classification of fractionated (staccato and intermittent) and smooth (bell, tower and plateau). They were also separated into three groups based on estimated bladder capacity (voided volume + post-void residual on ultrasound): high (>115%), low (<60%) or normal capacity.
The mean age was 8 (IQR 6.0-10.0) years and 25 (62.5%) patients were female. There was an increase in nonbell-shaped curves from the first (32.5%) to the second test (52.5%). The curve shape between the uroflowmetries based on ICCS classification showed a Kappa value of 0.349 (fair). Classifying curves as fractionated or smooth yielded a Kappa value of 0.714 (substantial) (table). The Bland-Altman test showed disagreement in the parameter of time to Qmax. There was a significant difference in categorizing bladder capacity as high, low, or normal: it was concordant in 63.6% for high, 68.4% for normal and 50% for low capacity (p = 0.001).
Despite the disagreement found classifying the curves based on the ICCS pattern, also demonstrated in other studies, there was a substantial agreement using the SPU criteria. It reinforces the greater reliability of the SPU system and it may be the key to reduce the subjectivity of uroflowmetry. Even though this classification being associated with a higher agreement in interpretation of the curves, repeating uroflowmetry does not present a clinically significant divergence that changes the patient's diagnostic workup. Our study is limited by the lack of EMG and larger sample.
Considering the flow curve pattern, the agreement between two uroflowmetries was substantial according to the SPU and only reasonable by the ICCS classification. Regardless of some differences found between the flows, a second uroflowmetry test might not have clinical relevance that justifies its recommendation for all patients.
尿流率测定是一种非侵入性检查，被视为下尿路症状（LUTS）患儿的一线评估方法。目前，国际儿童尿控协会（ICCS）建议对所有LUTS患者进行两次尿流率测定。本研究旨在评估两次尿流率测定在LUTS患儿中的差异及其对患者诊断检查和临床结局的影响。
对40例年龄在4至17岁的LUTS患儿进行前瞻性评估，连续进行两次尿流率测定和超声检查。根据ICCS曲线模式标准对其进行分类，并根据分节（断续和间歇性）和平滑（钟形、塔形和平台形）的SPU分类分为两组。还根据估计膀胱容量（超声测量的排尿量+排尿后残余尿量）将他们分为三组：高容量（>115%）、低容量（<60%）或正常容量。
平均年龄为8岁（四分位间距6.0 - 10.0），25例（62.5%）为女性。非钟形曲线从第一次检查时的32.5%增加到第二次检查时的52.5%。基于ICCS分类的两次尿流率测定之间的曲线形状Kappa值为0.349（一般）。将曲线分类为分节或平滑的Kappa值为0.714（高度一致）（表）。Bland - Altman检验显示在Qmax时间参数上存在差异。在将膀胱容量分类为高、低或正常方面存在显著差异：高容量时一致性为63.6%，正常容量时为68.4%，低容量时为50%（p = 0.001）。
尽管在根据ICCS模式对曲线进行分类时存在差异，其他研究也有类似情况，但使用SPU标准时存在高度一致性。这加强了SPU系统的更高可靠性，可能是减少尿流率测定主观性的关键。尽管这种分类在曲线解释上具有更高的一致性，但重复进行尿流率测定并未出现改变患者诊断检查的临床显著差异。我们的研究因缺乏肌电图检查和样本量较小而受到限制。
考虑到尿流曲线模式，根据SPU标准，两次尿流率测定之间的一致性高度一致，而根据ICCS分类仅为一般。尽管两次尿流之间存在一些差异，但第二次尿流率测定可能没有临床相关性，不足以证明对所有患者都推荐进行。
