Urinary tract infections (UTIs) are common in children, however, they are “sneaky and sly” because they frequently do not manifest as dysuria, as is common in adults.<sup>2 Altieri M.F., Camarca M.A., Bock G.H. Pediatric urinary tract infections Emerg Med Reports 1998 ;  19 : 1-8

Cliccare qui per andare alla sezione Riferimenti, 30 Mellick L.B. Pediatric urinary tract infections [editorial] Emerg Med Reports 1998 ;  19 : 1-8

Cliccare qui per andare alla sezione Riferimenti</sup> The diagnosis of UTI should be considered in all infants and children who present to the emergency department (ED) with classic symptoms of UTI, as well as in those with nonspecific symptoms, including fever, vomiting, abdominal, or flank pain. The goal of early diagnosis and treatment of UTIs in the pediatric population is the prevention of the complications of bacteremia and renal scarring. Although the most severe complication of pyelonephritis, renal scarring with progression to end stage renal disease is rare, aggressive treatment and work-up of pediatric urinary tract infection is preventive.

UTI is a nonspecific phrase used to define an inflammatory response to bacterial invasion anywhere within the renal system. Bacteria is present within the urine, as well as other signs of infection (nitrates, pyuria), and the patient may have local (dysuria, frequency, urgency) or systemic symptoms (fever, myalgias, rigors, nausea, vomiting, abdominal, or flank pain). Asymptomatic bacteriuria is defined as bacterial growth in the urine without signs or symptoms of infection. UTIs are divided into two overlapping categories—uncomplicated lower tract infection of cystitis and urethritis and upper tract infections of ureteritis, pyelitis (upper collecting system), and pyelonephritis (renal parenchyma). In general, the presence of fever, systemic symptoms, or back pain with infected urine indicates the presence of upper tract infection. Reliance upon the presence of fever alone to indicate the presence of an upper tract infection is problematic because renal scanning fails to show that fever is a reliable marker for pyelonephritis.<sup>36 Rushton H.G. The evaluation of acute pyelonephritis and renal scarring with DMSA Pediatr Nephrol 1997 ;  11 : 108-120  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti</sup> As well, studies that have analyzed fever as a marker for upper tract infection have shown a wide range of sensitivities (53%–84%) and specificities (44%–92%).<sup>9 Bergman D.A., Baltz Cooley R.D. , e al. Practice parameters: The diagnosis, treatment, and evaluation of the initial urinary tract infection in febrile infants and young children Pediatrics 1999 ;  103 : 834-853

Cliccare qui per andare alla sezione Riferimenti</sup> Also complicating the diagnosis of upper tract infection is the fact that there is no “gold standard” test for pyelonephritis. In the past, antibody-coated bacteria, and more recently, renal nuclear scanning have been used as indicators of pyelonephritis. However, the utility of these tests is still limited.

This chapter will discuss the spectrum of infections that fall under the heading of UTI. The diagnostic approach and management of the pediatric patient will be addressed. Infection in adults is addressed elsewhere.