Prostate biopsy (PB) is considered the gold standard for diagnosing prostate cancer (PCa), and it is the most frequently conducted procedure in urology departments (1). The conventional approach is often conducted via the transrectal (TR) route. However, TR prostate biopsy (TR-PB) is associated with a relatively high infection rate. Up to 5% of patients who undergo TR-PB require hospitalization due to sepsis (2, 3). Infection has been reported an important cause of death and morbidity among diabetic patients. these patients have a 3- to 4.9-fold risk of kidney infection. Diabetes impairs both innate and adaptive immune system, which impacts the inflammatory response and contribute to increased risk of infections (4, 5). In a prospective randomized trial, Lindert et al. (6) reported a 44% incidence of bacteriuria and a 16% incidence of bacteremia following TR-PB in men with negative preoperative urine cultures.

Transperineal prostate biopsies (TP-PBs) offer comparable cancer detection rates to transrectal biopsies and can be administered under local anesthesia in an outpatient setting (7). More importantly, TP-PB exhibits a lower risk of infection and better sampling advantages than does TR-PB. This approach has gradually gained widespread adoption in clinical practice (7, 8).

Recent investigations into TP-PB, both with and without antibiotic prophylaxis (AP), have reported infection rates that are not significantly different (1, 8). A systematic review and meta-analysis of eight non-randomized studies revealed no impact of AP on infection rates, fever occurrence, sepsis incidence, or readmission rates after TP-PB (9). Despite the relatively low risk of TP-PB-related infection, completely failing to use antibiotics remains challenge for the susceptible population (10, 11). A prophylactic antibiotic therapy was needed before prostate biopsy without making a clear description between the different techniques in the 2021 European Association of Urology (EAU) Guidelines. For the 2024 guidelines on urological infections, AP was recommended for TR-PB. There remains a controversy in both guidelines regarding the necessity of AP for TP-PB (12–14). Moreover, type 2 diabetes is one of the susceptible conditions that leads to a higher risk of infective complications. It is unclear AP is needed among type 2 diabetic patients following TP-PB.

This study aimed to evaluate the incidence of TP-PB-related infections among type 2 diabetic patients who underwent AP.

A total of 246 consecutive patients were analyzed. A total of 120 patients received TP-PB without AP, and 126 patients were administered AP before the procedure. The baseline data of the enrolled patients are presented in Table 1. In both cohorts, there were no statistically significant differences in terms of age, body weight, body mass index (BMI), systolic pressure, diastolic pressure, glycated hemoglobin a1c (HbA1c), low-density lipoprotein (LDL), estimated glomerular filtration rate (eGFR), prostate-specific antigen (PSA), prostate volume, biopsy cores, or duration of diabetes (p > 0.05, t-test). Additionally, white blood cell (WBC) counts before TP-PB were within the normal range in the two cohorts, with no statistically significant differences (p > 0.05, t-test).

Table 2 shows the non-infectious indicators of the two groups. The only significantly different domain was asymptomatic bacteriuria (Figure 1a, 8 in cohort A vs. 1 in cohort B, p < 0.05, 95%CI: 1.1–72.5, chi-square test), whereas other domains, including the prostate cancer detection rate (p > 0.05, chi-square test), postoperative hematuria (p > 0.05, chi-square test), and urinary retention (p > 0.05, Fisher’s exact test), were not significantly different.

Table 3 summarizes the TP-PB-related infectious indicators. The incidence of lower urinary tract symptoms (Figure 1b, p < 0.05, 95% CI: 3.0–21.6, chi-square test), fever (Figure 1c, p < 0.05, 95% CI: 1.3–81.3, chi-square test), and UTIs (Figure 1c, p < 0.05, 95% CI: 0.63–47.2, chi-square test) in Cohort A was greater than that in Cohort B. We have analyzed the microbiological profiles of patients who developed UTI. Among the 6 confirmed UTI cases (5 in Group A, 1 in Group B), urine cultures yielded: Escherichia coli in four patients (66.7%), Klebsiella pneumoniae in one patient (16.7%), and Enterococcus faecalis in one patient (16.7%). All E. coli isolates demonstrated susceptibility to cefixime (MIC ≤ 1 μg/mL), while the K. pneumoniae isolate showed intermediate susceptibility. Compared with that in Cohort B, the WBC count was significantly greater in Cohort A after TP-PB (Figure 1d, p < 0.05, Student’s t-test). Notably, sepsis was not detected in either group.

According to the 2024 Guidelines of the EAU, TP-PB has a lower risk of infectious complications than does TR-PB, and it is strongly recommended for high-risk patients (17). A shift to TP-PB for obtaining pathology specimens suspicious of CaP has taken place. Several studies have reported that TP-PB rarely causes sepsis without AP (18, 19). In one retrospective single-center cohort study, Sigle et al. (20) reported that TP-PB without AP is a safe procedure and results in fewer TP-PB-related infections, such as fever and sepsis. While TP-PB may curtail infection, it still induces infection ranging from approximately 0.10%–3% (10). One study reported that several factors, including diabetes, bacterial prostatitis, history of urinary retention, history of urinary infection, and number of cores, are associated with TP-PB-related infectious complications. The study revealed that diabetes was independent risk factor of TP-PB-related infectious complication. There was no exact reason for diabetes increasing the risk of the infectious complications (10, 11). In this study, we evaluated the effect of AP on diabetic patients with TP-PB.

In our study, there were eight cases of asymptomatic bacteriuria (6.7%), 30 cases of urinary irritation symptoms (25%), nine cases of fever (7.5%), and five cases of UTIs (4.2%) in the group without AP. None of the patients in either cohort developed sepsis. Compared with Cohort B, candidates without AP had a greater WBC count and were more likely to develop TP-PB-related infectious complications. This finding is inconsistent with recent findings (1, 2, 9).

A retrospective study carried out on 326 consecutive patients demonstrated that the routine use of antibiotics with TP-PB does not affect morbidity rates. However, the study did not perform subgroup analysis. Patient demographics were based on ethnicity, not basic medical history (1).

Pirola et al. (2) reported that the incidence of UTIs and bacteriuria in TP-PB is not correlated with AP. He suggested that AP is not needed in TP-PB patients. Notably, few diabetic patients were included in this study, and the outcome could not be used to determine the effect of AP on the TP-PB among diabetic patients (2).

The results from a systematic review also confirmed that fever, infection rate, readmission rate, and sepsis after TP-PB were not significantly different between the AP group and the non-AP group (9, 21). However, this meta-analysis neither performed heterogeneity analysis nor selected a specific population for analysis.

One randomized controlled trial demonstrated that patients who underwent TP-PB with no antibiotic use were non-inferior to those who received AP (3). The RCT and prior studies have suggested a low incidence of TP-PB-related infections, regardless of the use of APs (3, 5, 22). However, these studies were underpowered and had limitations for the populations (3, 5, 22).

The novelty of this study lies in the special population of diabetic patients. Owing to its susceptibility to infection, AP is vital for diabetic patients undergoing TP-PB. However, there are several limitations to this study. First, the two cohorts were only from a single center, and the number of patients was small. Moreover, we did not collect data on the medication history of diabetes and did not determine the correlation between diabetes and TP-PB-related infections. Finally, we excluded other high-risk factors and reduced the complexity of the data, so we are uncertain about the role of AP in TP-PB-related infection under complex conditions.

Thus, diabetic patients receiving TP-PB may need AP. It could decrease the incidence of TP-PB-related complications, such as asymptomatic bacteriuria, urinary irritation symptoms, fever, and UTIs. AP could still be needed in TP-PB candidates with a high risk of infections in the future.