NEW YORK (Reuters Health) Aug 23 - Although point-of-care urinalysis yields fast results, its utility is limited by a lack of sensitivity for diagnosing pediatric urinary tract infection (UTI), according to new research.
Urinalysis is commonly used to diagnose UTI in young children who present with nonspecific symptoms, but previous studies have called into question its accuracy.
The new work, by Dr. Andrea T. Cruz and colleagues at Baylor College of Medicine, Houston, Texas, compared point-of-care urinalysis with laboratory urinalysis in more than 40,000 children who had had both a urinalysis and a urine culture done.
There were 43,452 specimens with laboratory-performed urinalysis, 6,492 specimens with point-of-care urinalysis, and 2,908 specimens with both urinalyses performed. Urine cultures were consistent for UTI in 7.5% of specimens.
Point-of-care urinalysis yielded 82.5% sensitivity, 81.3% specificity, 33.9% positive predictive value, and 97.6% negative predictive value, according to the report, online July 29 in the American Journal of Emergency Medicine.
Laboratory-based urinalysis was more sensitive (89.1%) and yielded significantly higher negative predictive value (98.9%) than point-of-care urinalysis. On the other hand, it was less specific (76.1%), with a positive predictive value of just 22.7%.
Sensitivity tended to increase with increasing patient age. Laboratory-performed urinalysis was more sensitive in girls than in boys, and point-of-care urinalysis was much more specific in boys than in girls.
"Although point-of-care urinalyses offer more rapid turnaround times, the sensitivity is greater for laboratory-performed urinalyses," the researchers write. "Given the difficulty in following up pediatric emergency department patients after discharge as well as the potential morbidity from untreated UTIs, the rapidity of the point-of-care urinalysis must be balanced against the lower sensitivity of this assay."
"Future studies could evaluate the benefit of more accurate diagnosis potentially outweighing the longer pediatric emergency department length of stay associated with a laboratory-performed urinalysis, from both clinical and cost perspectives," they add.
Dr. Cruz did not respond to a request for comments.
Am J Emerg Med 2013.
Reuters Health Information © 2013