RESUMO
The pre-analytical step of the cytobacteriological examination of urine (CBEU) is one of the most critical in microbiology. The objectives of our study were to determine the rate of urinary contamination and to analyze the factors that would facilitate this in order to propose solutions to this problem. METHOD: This is a 26-month descriptive study including all CBEU requests to our laboratory. Urine was treated in accordance with the recommendations of the medical microbiology recommendations. Urine was considered contaminated in the case of polymorphic culture with at least three different types of germs with a count from 103 CFU/mL. RESULTS: We collected 16,412 CBEU requests. Urine was contaminated in 4,830 cases (29.43%). Of the contaminated urine, 39.23% (n=1,895) was from emergency departments, 79.44% (n=3,837) was collected in the middle of the stream, 69.83% (n=3,373) was from a female patient and 16.34% (n=789) was from children under the age of 5. DISCUSSION AND CONCLUSION: To reduce urine contamination, quality instructions describing sampling procedures should be available and samples in the middle of the stream and through the collection adhesive bags should be replaced by sus-pubic puncture samples in children, whenever the profit/risk ratio of this method is favourable.