Summary of findings for the main comparison. Antimicrobial compared to placebo or no antibiotics for preventing urinary tract infections in adults undergoing cystoscopy.
| Antimicrobial compared to placebo or no antibiotics for preventing urinary tract infections in adults undergoing cystoscopy | |||||
| Patient or population: people undergoing cystoscopy Setting: various Intervention: antimicrobial Comparison: placebo or no antibiotics | |||||
| Outcomes | № of participants (studies) | Certainty of the evidence (GRADE) | Relative effect (95% CI) | Anticipated absolute effects* (95% CI) | |
| Risk with placebo or no antibiotics | Risk difference with antimicrobial | ||||
| Systemic UTI Follow‐up: range 1–30 days | 504 (5 RCTs) | ⊕⊕⊝⊝ Lowa,b | RR 1.12 (0.38 to 3.32) | Study population | |
| 20 per 1000 | 2 more per 1000 (12 fewer to 46 more) | ||||
| Symptomatic UTI Follow‐up: range 1–30 days | 5441 (11 RCTs) | ⊕⊕⊝⊝ Lowa,c | RR 0.49 (0.28 to 0.86) | Study population | |
| 58 per 1000 | 30 fewer per 1000 (42 fewer to 8 fewer) | ||||
| Serious adverse events Follow‐up: range 1–30 days | 630 (4 RCTs) | ⊕⊝⊝⊝ Very lowa,d | RR approximately 1 | 0/326 participants receiving prophylactic antibiotics and 0/304 participants receiving control had a serious adverse event. | |
| Minor adverse events Follow‐up: range 1–30 days | 630 (4 RCTs) | ⊕⊕⊝⊝ Lowa,b | RR 2.82 (0.54 to 14.80) | Study population | |
| 3 per 1000 | 6 more per 1000 (2 fewer to 46 more) | ||||
| Localized UTI Follow‐up: range 1–30 days | 200 (1 RCT) | ⊕⊝⊝⊝ Very lowa,d | RR 1.00 (0.06 to 15.77) | Study population | |
| 10 per 1000 | 0 fewer per 1000 (9 fewer to 152 more) | ||||
| Bacterial resistance Follow‐up: range 1–30 days | 38 (2 RCTs) | ⊕⊝⊝⊝ Very lowa,d,e | RR 1.73 (1.04 to 2.87) | Study population | |
| 406 per 1000 | 297 more per 1000 (16 more to 760 more) | ||||
| *The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; RCT: randomized controlled trial; RR: risk ratio; UTI: urinary tract infection. | |||||
| GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect. | |||||
aDowngraded for study limitations (–1) related to unclear or high risk of selection, performance, detection, and selective reporting bias.
bDowngraded for imprecision (–1) due to wide confidence intervals that included both no effect and increased risk.
cDowngraded for publication bias (–1) detected by asymmetry funnel plot.
dDowngraded for imprecision (–2) due to wide confidence interval around the pooled estimate which included no effect, small sample size, and few events.
eDowngraded for indirectness (–2) due to urine culture being performed after cystoscopy, and antibiotic prophylaxis would kill sensitive bacteria, thus leaving the percentage of bacterial resistance higher than the control group. As a result, even the pooled result could not deduce that antibiotic prophylaxis may have increased bacterial resistance from current results.