To evaluate the efficacy and safety of fosfomycin-trometamol (FMT) in the treatment of acute uncomplicated lower urinary tract infection (LUTI).

The medical records of acute uncomplicated LUTI patients, who had acute uncomplicated LUTI and received FMT or levofloxacin (LEV) in Qingdao Municipal Hospital from January 2015 to October 2017, were collected and analyzed retrospectively. Comparisons were made between the FMT group and the LEV group to investigate the patients' clinical efficacy, bacteriological efficacy, bacteria isolated from urine cultures, the susceptibility of isolated strains to drugs and the occurrence of adverse reactions.

Seventy patients entered the FMT group, including 31 males and 39 females, aged from 29 to 68 years with an average age of (51±10) years.56 patients entered the LEV group, including 26 males and 30 females, aged from 31 to 66 years with an average age of (52±10) years.The treatment periods of patients in the two groups were 3 to 7 days. Routine blood tests and liver and renal function tests were normal before the treatment. After the treatments, 59 patients were cured, 5 patients improved, and the clinical efficacy was 91.4% (64/70) in the FMT group; while 28 patients were cured, 4 patients improved, and the clinical efficacy was 57.1% (32/56) in the LEV group. And the difference was statistically significant (χ²=20.16, P<0.001). Positive bacteria were found in urine culture of 46 patients in the FMT group, including 35 strains of Escherichia coli[17 of which were extended-spectrum β-lactamases (ESBL)-producing Escherichia coli], 3 strains of Bacillus proteus [1 of which was ESBL-producing Bacillus proteus], 3 strains of Enterococous faecalis, 3 strains of Staphylococcus aureus, and 2 strains of Staphylococcus epidermidis. Positive bacteria were found in urine culture of 37 patients in the LEV group, including 29 strains of Escherichia coli (14 of which were ESBL-producing Escherichia coli), 3 strains of Bacillus proteus (1 of which was ESBL-producing Bacillus proteus), 2 strains of Enterococous faecalis, 1 strain of Staphylococcus aureus, and 2 strains of Staphylococcus epidermidis. Bacteriological efficacy were 91.3% and 56.8%, for the FMT group and the LEV group, respectively and the difference was statistically significant (χ²=13.38, P<0.001). Thirteen of the 17 ESBL-producing Escherichia coli strains isolated from patients in the FMT group were susceptible to FMT (susceptibility rate: 76.5%). Five of the 14 ESBL-producing Escherichia coli strains isolated from patients in the LEV group were susceptible to LEV (susceptibility rate: 35.7%). And the difference was statistically significant (P=0.033). The difference of the incidence of adverse reactions was not statistically significant between the FMT group and the LEV group [11.4% (8/70) vs 16.1% (9/56), χ²=0.575, P=0.448].

FMT was more effective and safer than LEV in the treatment of patients with acute uncomplicated LUTI.

Fosfomycin; Tromethamine; Urinary tract infections; Safety