Comparative bacteriologic study of urine obtained from children by percutaneous suprapubic aspiration of the bladder and by catheter.

A comparative bacteriologic study of urine obtained by catheter and by suprapubic aspiration was performed in a group of 42 children who were presumed free from clinical infection of the urinary tract, and who were undergoing elective surgery for conditions that did not involve manipulation of the urinary tract. There was complete diagnostic correlation between urine obtained by suprapubic aspiration and the clinical impression. There was a 92.8% diagnostic correlation between the first few milliliters of urine obtained by catheter (C1) and the specimens obtained by suprapubic aspiration, and there was a 97.5% diagnostic correlation between the second few milliliters of urine obtained by catheter (C2) and the suprapubic specimens. Three patients had significant bacterial counts in specimens obtained by catheter, and on this basis alone, a diagnosis of pyelonephritis might have been made erroneously. However, the C2 specimens showed a significant count in only one of the three patients, pointing up the importance of discarding the initial few milliliters of urine obtained by catheterization. In this one patient, the suprapubic specimen was sterile, the C2 specimen grew out 3,100 colonies of E. coli/ml of urine, while a subsequent clean voided specimen did not exhibit significant growth. The patient remained in good health and, in view of the sterile specimen obtained by suprapubic aspiration, we believe that the organisms grown in the C2 specimen were due to contamination. Gram stains of all specimens were negative for organisms. The entire group was followed from 1 to 5 months postoperatively, both in the outpatient department and by questionnaire. Sixteen children returned to the clinic for follow-up examination of clean voided specimens and further study, if indicated. All patients in the study were free from infection of the urinary tract within a period of 4 to 6 months after catheterization. Thus, while organisms were introduced into the urine of children during the procedure of catheterization and in apparently significant quantities, these organisms were not responsible for the initiation of a urinary tract infection in this admittedly small group of patients. It is imperative, however, that all specimens obtained by catheter be collected by the physician-in-charge or under his direct supervision, employing acceptable aseptic techniques. It is our opinion that while properly collected clean voided specimens may be used in most instances for making the diagnosis of true bacteriuria in children, catheterization, when properly done, should not be withheld for fear of producing infection of the urinary tract. It must remain a necessary procedure in the diagnosis and management of infections of the urinary tract in certain cases, notably the following: a) Where there is urinary retention. b) Where repeated study of clean voided specimens yields borderline or doubtful results. c) Where the patient is so acutely ill that there is a need for immediate antimicrobial therapy and no time for multiple specimens to be obtained. d) Where the patient is unable or unwilling to cooperate.