{Reference Type}: Journal Article
{Title}: Role of urine Gram stain in young febrile infants with a suspected urinary tract infection: a cohort study.
{Author}: Gomez B;Mier A;Ugedo A;Aguirre-Quiñonero A;Benito J;Mintegi S;
{Journal}: Arch Dis Child
{Volume}: 0
{Issue}: 0
{Year}: 2024 Jun 21
{Factor}: 4.92
{DOI}: 10.1136/archdischild-2024-327182
{Abstract}: <B>OBJECTIVE: </B>To analyse the performance of the urine Gram stain for predicting a positive urine culture (UC) in young infants with fever without source (FWS) and pyuria.<BR><B>METHODS: </B>Observational study; secondary analysis of a prospective registry-based cohort study.<BR><B>METHODS: </B>Paediatric emergency department; tertiary teaching hospital.<BR><B>METHODS: </B>Infants ≤90 days old with FWS, pyuria and urine Gram stain requested seen between 2010 and 2022.<BR><B>METHODS: </B>Performance of the Gram stain, defined as positive if any bacteria were seen, for predicting urinary tract infection (UTI: UC by urethral catheterisation growing >10 000 CFU/mL of a single bacterial pathogen).<BR><B>RESULTS: </B>Among 367 febrile infants with pyuria, 281 (76.6%) had a positive Gram stain and 306 (83.3%) had a positive UC (277; 90.5% Escherichia coli).Rates of positive UC in patients with positive and negative Gram stains were 97.2% and 38.4%, respectively (p<0.01), showing a sensitivity of 89.2% (95% CI: 85.2% to 92.2%) and a specificity of 86.9% (95% CI: 76.2% to 93.2%). Sensitivity was lower for diagnosing UTIs caused by bacteria other than E. coli (69.0% vs 91.3% for UTIs caused by E. coli; p<0.01).Two (2.1%) of the 86 infants with negative Gram stains were diagnosed with bacteraemia unrelated to a UTI (Streptococcus pneumoniae and Staphylococcus aureus).<BR><B>CONCLUSIONS: </B>Around a third of infants with pyuria and a negative Gram stain will eventually be diagnosed with a UTI. These patients have a higher rate of UTIs caused by bacteria other than E. coli. Bacterial infections other than UTIs should also be considered in such cases.