Treatment of Inpatient Urinary Tract Infections

Classification and Initial Assessment

The European Urology guidelines recommend that UTIs in hospitalized patients be classified as complicated UTIs (cUTIs), which are more challenging to eradicate compared to uncomplicated infections 1
Common factors associated with complicated UTIs include obstruction, foreign body presence, incomplete voiding, recent history of instrumentation, male gender, pregnancy, diabetes mellitus, immunosuppression, healthcare-associated infections, and presence of multidrug-resistant organisms 1
Urine culture and susceptibility testing should always be obtained before initiating antibiotics to guide targeted therapy 1

For patients with systemic symptoms, the European Urology guidelines recommend an intravenous third-generation cephalosporin, or a combination of amoxicillin plus an aminoglycoside, or a second-generation cephalosporin plus an aminoglycoside 1, 2, 3
For catheter-associated UTIs, similar regimens as above should be used, with consideration of broader coverage due to higher risk of resistant organisms 1, 2
The European Urology guidelines recommend monitoring for signs of systemic infection as CA-UTIs are the leading cause of secondary healthcare-associated bacteremia 2

The European Urology guidelines recommend treatment for 7-14 days, with 14 days recommended for male patients where prostatitis cannot be excluded 1, 4
For gram-negative bacteremia from a urinary source, 7 days of treatment is recommended 4

The most common species found in cultures of cUTIs include E. coli, Proteus spp., Klebsiella spp., Pseudomonas spp., Serratia spp., and Enterococcus spp. 1
Resistance is more likely in cUTIs compared to uncomplicated UTIs, and appropriate management of any urological abnormality or underlying complicating factor is mandatory 1

Once culture results are available and the patient shows clinical improvement, transition to an appropriate oral agent based on susceptibility testing should occur 1
Patients should be hemodynamically stable and able to retain oral medications before switching to oral therapy 5

Agents that are excreted in the urine but do not achieve therapeutic concentrations in the bloodstream, such as nitrofurantoin, should not be used for treating inpatient UTIs 5
Fluoroquinolone use should be restricted due to increased rates of resistance and should not be used as first-line empiric treatment for complicated UTIs in patients from urology departments 1
For patients with indwelling catheters, a negative urinalysis can rule out CAUTI, but a positive urinalysis does not necessarily indicate infection due to its low specificity in catheterized patients 6
Carbapenems and novel broad-spectrum antimicrobial agents should only be considered in patients with early culture results indicating the presence of multidrug-resistant organisms 3