[Utility of distinct urinalysis parameters in the diagnosis of urinary tract infections]

A review of the scientific evidence available on the validity of urinalysis in the diagnosis of urinary tract infection in childhood is presented. Numerous studies evaluating the validity of distinct urinalysis parameters have been published. Although many of these studies have methodological deficiencies, the indicators of validity evaluated in the various systematic reviews can be assumed to be applicable to clinical practice; however, the grade of evidence supporting these studies is less than optimal. There are some parameters or combinations of parameters that have better sensitivity or specificity, but few present sufficiently high positive and negative predictive values simultaneously to form the exclusive basis for diagnosis. Bacteriuria presents certain advantages over other parameters, although this test is not routinely available and loses validity in non-sterile samples. Nevertheless, there are several circumstances that can modify the applicability of these tests in clinical practice: the technique used in urine collection, the patient's age and clinical status, and especially the degree of urgency with which the diagnosis is required.