Neonatal Bacteriuria — The Value of Bladder Puncture in Resolving Problems of Interpretation Arising from Voided Urine Specimens

Neonatal Bacteriuria — The value of bladder puncture in resolving problems of interpretation arising from voided urine specimens. During a study of neonatal bacteriuria in 1460 infants born consecutively it was found that 76% had either sterile urine, or less than 10 × 10 6 organisms/1 (10,000 organisms/ml) in a single ‘clean catch’ specimen. To establish the level of bacteriuria in voided specimens which correlates with bacteriuria obtained by aspirating urine suprapubically, check bladder punctures were carried out. This was done in infants with varying levels of colony counts obtained from voided specimens. No bladder puncture specimens showed evidence of infection when the colony count on the voided urine culture was less than 10 × 10 6 organisms/1. When the colony count on the voided urine culture was between 10 and 100 × 10 6 organisms/1, 2.2% of bladder puncture urines showed evidence of infection. When the voided urine colony count exceeded 100 × 10 6 organisms/1, 11.1% of bladder punctures showed evidence of infection. There was no significant correlation between baoteriuria and pyuria or proteinuria. While repeated collection and culture of ‘clean catch’ urines may reduce the Ca fusion due to contaminated specimens, this approach can be time consuming. It is recommended that if the colony count on a carefully collected ‘clean catch’ specimen exceeds 10 × 10 6 organisms/1, or if the infant has symptoms suggestive of infection, bladder puncture should be performed.