Evaluation of urine collection methods for the diagnosis of urinary tract infection in children.

OBJECTIVE: To evaluate the accuracy of urine sample collection methods among children suspected of having urinary tract infections.

SUBJECTS AND METHODS: Four methods for urine sample collection were evaluated in 1,067 children aged 0-16 years with suspected urinary tract infections over 2 months at Dr. Sami Ulus Children's Hospital. Within 30 min of collection, all specimens were sent to the laboratory, refrigerated and processed according to standard hospital microbiological procedures. Urine samples were analyzed using routine culture techniques.

RESULTS: At initial sending of the urine culture, 617 (57.8%) had negative culture results, 145 (13.6%) had positive culture results, and 305 (28.6%) had evidence of bacterial contamination. Clean catch specimens showed a contamination rate of 14.3% and urethral catheterization specimens showed a similar contamination rate (14.3%). However, urethral catheterization was preferred in only a small number of cases (n=7). Suprapubic aspiration was also used in a small number of cases (n: 11) and the contamination rate for suprapubic aspiration was 9.1% (n: 1/11). The contamination rate for sterile urine bag was 43.9%, significantly higher than the other methods (p<0.001).

CONCLUSION: Suprapubic aspiration showed the lowest contamination rate and sterile urine bag showed the highest contamination rate among 4 methods of urine sample collection. Contaminated specimens, needed to be repeated and this procedure increased the cost of urine culture. In conclusion, measures should be taken to reduce the contamination rate in our center. This is an area where further investigation is required.