We read with interest the article by Lu et al regarding routine pre-operative urinalysis. 1 In review of spine fusion surgeries performed by orthopedic surgeons or neurosurgeons at our facilities from January 2025 through June 2026, 1316 and 1379 were performed on females and males, respectively. During this time, fusion surgical site infections (SSIs) caused by gram-negative bacilli occurred in 20 and 2 females and males, respectively. As such, the risk of fusion SSIs caused by gram-negative bacilli in females is significantly greater than males (RR 9.5; 95% CI 2.2-40.7). In many of these cases, the causative gram-negative bacteria were isolated in a urine culture prior to, or shortly after, the surgical procedure.
A predilection of SSIs caused by gram-negative bacilli in fusions involving the lumbosacral region has been previously demonstrated.2-4 Thus, it is not surprising that most of these infections in women originate in the genitourinary tract.
As a result of these findings, we have added gentamicin to cefazolin for fusion surgeries involving the lumbar spine since most of the gram-negative bacteria causing our fusion SSIs are gentamicin-susceptible. In addition, the following pragmatic strategies should be considered: during the pre-operative evaluation by the surgical team, they should question patients about prior urinary tract infections (UTIs) and review microbiology culture results for evidence of past UTIs; if a patient has a current UTI or a history of recurrent UTIs, postpone elective surgery and discuss preventative strategies with the patient’s primary care physician including increased daily fluid intake, 5 vaginal estrogen if post-menopausal, 6 and possible use of methenamine prophylaxis7,8; if the patient has a history of urinary incontinence, assess the need for intermittent straight catheterization to reduce potential soilage of the surgical site; and assessment of surgical wound care protocols should be done to be certain the post-operative dressing is intact with prompt replacement if not intact or soiled. Although routine pre-operative urinalysis does not appear to be helpful, 1 review of our fusion SSIs suggests this may have utility in women with a history of UTIs.
A pre-operative team approach involving the surgeon, anesthesiologist, primary care physician, infectious diseases consultant, and the patient, particularly women scheduled for spinal fusion surgery, may well reduce risk of these infections in the future.
Footnotes
Funding: The authors received no financial support for the research, authorship, and/or publication of this article.
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
ORCID iD
Leonard A. Mermel https://orcid.org/0000-0002-8898-7406
References
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