Are asymptomatic bacteriuria (presence of bacteria in urine) and asymptomatic pyuria (presence of pus in urine) contraindications for cataract surgery?

Asymptomatic Bacteriuria and Pyuria Are NOT Contraindications for Cataract Surgery

Asymptomatic bacteriuria and asymptomatic pyuria should not be screened for or treated prior to cataract surgery, and their presence does not require postponement of the procedure. 1

Guideline-Based Recommendation

The 2019 Infectious Diseases Society of America (IDSA) guidelines provide a strong recommendation against screening for or treating asymptomatic bacteriuria (ASB) in patients undergoing elective nonurologic surgery (strong recommendation, low-quality evidence). 1 Cataract surgery falls squarely into this category as a nonurologic, elective procedure.

Evidence Supporting This Approach

Lack of Benefit from Treatment

• Studies of 3,167 preoperative patients across orthopedic, cardiac, and vascular surgeries found that treating ASB did not reduce postoperative complications, including surgical site infections or prosthetic joint infections. 1

• The baseline risk of symptomatic UTI in untreated ASB patients was only 36 per 1,000 patients, compared to 140 per 1,000 for surgical site infections—demonstrating that urinary bacteria are not a significant source of surgical complications. 1

• Importantly, patients who developed orthopedic implant infections postoperatively had different pathogens isolated from the surgical site compared to their preoperative urine, strongly suggesting the urine was not the infection source. 1

Harms of Unnecessary Treatment

• Treating ASB increases antimicrobial resistance, risk of Clostridioides difficile infection, adverse drug effects, and healthcare costs without improving outcomes. 1, 2

• The IDSA emphasizes that "there is high certainty that any antimicrobial increases the risk of harm" even when the magnitude of benefit is uncertain. 1

Critical Distinction: When ASB DOES Matter

The IDSA guidelines make a crucial exception: ASB should be screened for and treated only before endoscopic urologic procedures that breach the mucosal lining (such as transurethral resection of the prostate or bladder, ureteroscopy with lithotripsy). 1 This is because these procedures enter a contaminated field and carry substantial risk of postoperative sepsis when bacteriuria is present. 1

Cataract surgery involves no mucosal trauma to the urinary tract and poses no such risk.

Regarding Pyuria Specifically

• Pyuria (white blood cells in urine) commonly accompanies ASB but does not change management recommendations for nonurologic surgery. 1

• The presence of pyuria without urinary symptoms does not indicate infection requiring treatment and should not delay elective surgery. 3, 4

Common Pitfalls to Avoid

• Do not order preoperative urinalysis routinely for cataract surgery patients—this leads to unnecessary findings that prompt inappropriate treatment. 1, 2

• Do not treat ASB discovered incidentally on preoperative testing unless the patient is pregnant or undergoing urologic procedures with mucosal trauma. 4, 5, 2

• One cardiac surgery study of 1,165 patients found no difference in postoperative infection rates between those with preoperative bacteriuria and controls, concluding that urinalysis is "not necessary and not cost beneficial" for asymptomatic patients. 6

Practical Algorithm

1. Do not screen asymptomatic cataract surgery patients for bacteriuria or pyuria 1
2. If ASB is discovered incidentally, proceed with surgery without treatment 1
3. Only treat if the patient develops urinary symptoms (dysuria, frequency, urgency, suprapubic pain, fever) 1, 2
4. Proceed with standard perioperative prophylaxis as indicated for the ophthalmic procedure itself 1