Is Benign Prostatic Hyperplasia a Perpetrator for Periprosthetic Joint Infection?: Commentary on an article by Hamidreza Yazdi, MD, et al.: "Symptomatic Benign Prostatic Hyperplasia. A Risk Factor for Periprosthetic Joint Infection in Male Patients".

Abstract

Commentary In the current era, total joint arthroplasty (TJA) is considered to be safe and cost-effective and a successful procedure to improve quality of life. However, a periprosthetic joint infection (PJI) is a huge setback to the patient, family, and surgeon alike. Although the overall incidence of PJI following TJA is low, there is high morbidity (persistent pain, prolonged hospital stay, multiple surgical procedures, functional loss) and even mortality associated with PJI. Over the last couple of decades, several hundred studies have been done on the prevention, diagnosis, treatment, and outcomes of PJI. We are certainly making progress by lowering the incidence of infection, but the search for causes is relentless. In the current study, Yazdi et al. performed a retrospective study to explore another potential cause for PJI: benign prostatic hyperplasia (BPH) in male patients. Anecdotally, I have also observed BPH to be a potential cause for PJI, given that my current practice is dominated by male patients. Yazdi et al. reviewed 12,902 patients from their institution registry database and grouped them into symptomatic and non-symptomatic BPH groups. They further matched patients with symptomatic BPH (n = 250) with a non-symptomatic BPH control group in a 1:3 ratio. The PJI rate was 7.9% in the symptomatic group compared with 2.8% in the control group. Multivariate regression analysis in unmatched groups showed that symptomatic BPH was a strong independent risk factor for PJI. Symptomatic BPH remained a significant risk factor for PJI after matching for variables related to outcomes. Yazdi et al. concluded that symptomatic BPH might be a reason for the high incidence of PJI in male patients. Interestingly, in the current study, multivariate analysis also showed that symptomatic BPH carried a risk higher than even diabetes mellitus for PJI. Another interesting finding in the current study is that symptomatic BPH showed a higher trend toward acute PJI. However, there is no obvious pathomechanism as to why BPH could cause PJI. It is hypothesized that the collection of excess urine in the bladder in the perioperative period or high post-void residual urine in patients with symptomatic BPH increases the bacterial load, subsequently potentiating the spread of the infection to the newly implanted joint prosthesis. With the current trend of patients undergoing fast-track TJA under spinal anesthesia, the incidence of postoperative urinary retention is on the rise1. The incidence of postoperative urinary retention may even be higher with symptomatic BPH and may potentially increase the risk of PJI, especially if BPH is not treated before the surgical procedure. Similarly, the current trend of multimodal perioperative pain management for TJA includes a scopolamine (anticholinergic) patch, given its ease of use and successful avoidance of postoperative nausea and vomiting2. In patients with symptomatic BPH, scopolamine might further increase BPH-related urinary retention or post-void residual urine and subsequent risk of PJI. This preliminary study identifies BPH as a potential cause for PJI in male patients. The study had several limitations: it was a retrospective study, there were potential concerns with regard to the data collection method, the duration of follow-up was 1 year, and there were no explicit data on catheterization done in the perioperative period. There are several strengths to this study as well. The Rothman Institute has a reputation for good patient follow-up with low dropout rates, this is a single-institution study, and there was a matched-cohort study design to minimize the effect of confounding variables. For these reasons, I consider this a well-conducted outcome study. The total number of TJAs performed annually has been on an upward trend globally. It is expected to reach 4 million annually by 2030 in the United States3 alone, in contrast to about 1 million per year currently. Any and every step to reduce the incidence of PJI is worth taking into consideration considering the economic and individual patient burden of treating a PJI. Kee et al. demonstrated that nearly half of all patients undergoing early revision arthroplasties had at least 1 modifiable risk factor and emphasized proper patient selection and preoperative optimization of modifiable risk factors to minimize the risk of adverse outcomes following TJA4, but BPH was not a part of the study. It would be worthwhile to also include symptomatic BPH as a modifiable risk factor and to preoperatively optimize patients to reduce PJI. This study by Yazdi et al. will serve as a great precursor for further multicenter, larger population-based studies to assess any regional or geographical biases and confounding factors.