Introduction & Objective : Circumcised males are 85% less likely to develop a UTI in the first year of life than uncircumcised males. Because UTI’s are often the first sign of a bladder or renal anomaly many of these boys get screened with renal bladder ultrasounds (RBUS) and voiding cystourethrograms (VCUG). The purpose of this study was to see if Proteus UTI’s were more likely associated with an uncircumcised foreskin than other bacterial species and if the incidence of anatomical abnormalities was less in these boys.
Methods : We retrospectively reviewed a cohort of male patients under 18 years of age who presented to our emergency department (ED) and had positive urine cultures from 2011-2015. Males under 18 years of age with >50,000 CFU/mL Staphylococcal, Streptococcal, Proteus or Escherichia UTIs on clean catch or catheterized specimens were included. Both febrile and afebrile UTIs were included. Patients on intermittent catheterization or with augmented bladders were excluded. Ultrasound and cystogram images were reviewed on patients when available. Circumcision status was determined from the charts. Chi squared and Fisher’s exact tests were performed using Stata software, version 14.0 SE (Stata Corporation, College Station, Texas, USA).
Results : A total of 703 males with urine culture results from the ED were evaluated and 357 met inclusion criteria. Median age was 7.7 months (2.5- 46.8 months IQR). Forty two Proteus, 16 Staphylococcus, 7 Streptococcus and 292 Escherichia UTIs were included. Patients who present with a Proteus infection are far less likely to be circumcised (1/37 or 2.7%) than Escherichia (37/226 or 16.4%) or a gram positive organism (15/20 or 75% p<0.0001). Proteus UTIs were associated with a lower percentage of abnormal ultrasounds (3/19 or 13.64%) when compated to Staph (6/11 or 54.6%), Strep (3/6 or 50%) or Escherichia (61/203 or 30.05%) respectively (Fisher's Exact Test p=0.05). 19.55% of all patients (26/133) who had a cystogram done had any abnormalities. Among those, Proteus had the lowest rate (2/13 or 15.38%) compared to Staphylococcus (5/7 or 71.43%) Streptococcus (1/2 or 50%) or Escherichia (18/111 or 16.22%) although this did not reach statistical significance. None of the Proteus UTIs were associated with VUR.
Conclusions : Boys presenting with a urine culture positive for Proteus are almost exclusively uncircumcised and are less likely to have associated urinary tract abnormalities on imaging when compared to other uropathogens. Imaging after the 1st Proteus UTI in boys may not be necessary.