Association between post-craniotomy Propionibacterium acnes infection and dural implants: a case–control study

Comprehensive analysis of risk factors and pathogenetic characteristics associated with surgical site infections following craniotomy procedures

Craniotomies are intricate neurosurgical procedures susceptible to post-operative complications, among which surgical site infections (SSIs) are particularly concerning. This study sought to elucidate the potential risk factors and pathogenetic characteristics associated with SSIs following craniotomy procedures in a clinical setting. A retrospective study was conducted from May 2020 to May 2023, examining patients subjected to elective or emergency craniotomies. The cohort underwent post-operative surveillance for SSIs, facilitating patient classification into SSI and Non-SSI groups based on infection occurrence. Data collection encapsulated demographic and clinical parameters, including American Society of Anesthesiologists (ASA) classifications, and operative factors. SSIs were diagnosed via an integrated approach combining clinical symptoms, microbiological culture findings and pertinent laboratory tests. A rigorous statistical methodology employing IBM's SPSS version 27.0 was utilised for data analysis. In a univariate analysis, significant risk factors for post-craniotomy SSIs were identified, with patients aged over 60 displaying a pronounced susceptibility. Moreover, surgeries exceeding a duration of 4 h heightened infection risks. Elevated ASA grades denoted an increased prevalence of SSIs, as did emergency procedures and higher National Nosocomial Infections Surveillance scores. Multivariate analysis pinpointed epidural/subdural drainage as a protective measure against SSIs, whereas emergency surgeries, operative times beyond 4 h and subsequent surgeries within the hospital stay amplified infection risks. Notably, coagulase-negative Staphylococcus dominated the identified pathogens at 28.09%, followed by Escherichia coli (17.98%), Klebsiella pneumoniae (10.11%) and Staphylococcus aureus (11.24%), underscoring the need for diverse prophylactic measures. SSIs following craniotomies present a multifaceted challenge influenced by a confluence of patient-related, operative and post-operative determinants. Understanding these risk factors is paramount in refining surgical protocols and post-operative care strategies to mitigate SSI incidence.

Risk Factors and Outcomes of Cutibacterium acnes Postoperative Central Nervous System Infection: A Case-Control Study

OBJECTIVE

Cutibacterium acnes has emerged as a significant cause of postoperative central nervous system infections (PCNSIs). We sought to determine risk factors and outcomes associated with C. acnes PCNSI.

METHODS

This was a single-center 1:1 case-control study of patients with monobacterial C. acnes-associated PCNSI (cases) and unmatched controls with PCNSI caused by aerobic organisms. Patient and procedure-related characteristics were compared between groups. The main outcome was cure at 90 days after diagnosis. Mortality and neurologic disability were secondary outcomes.

RESULTS

We identified 13 patients with C. acnes PCNSI and 13 controls. All patients had postoperative intracranial abscess. Onset of infection was significantly later for cases versus controls (median and range, 22 [19-116] days and 15 [1-27] days, respectively; P = 0.002). Prolonged anaerobic incubation was required for C. acnes isolation (median, 8 days vs. 2 days for aerobic pathogens; P < 0.0001). The use of sealant and implants, fever at presentation, and white blood cell and C-reactive protein levels were similar between the 2 groups. All patients underwent surgical drainage. Patients received a median of 4 antibiotic drugs and 85 antibiotic days of treatment, with no significant between-group differences. Cure at 90 days was achieved for 10 patients (76.9%) with C. acnes PCNSI and 11 (84.6%) controls (P = 1.0).

CONCLUSIONS

C. acnes PCNSI presents later than infection with aerobic bacteria but is associated with similar risk factors and clinical outcomes. These results underscore the importance of prolonged anaerobic incubation to optimize the recovery of C. acnes in the laboratory.

Surgical site infections after craniotomy: a matched health-care cost and length of stay study

OBJECTIVE

To assess the extra health-care costs and length of stay resulting from surgical site infection (SSI), as well as to identify the most frequent aetiological microorganisms of SSIs among Jordanian craniotomy surgery patients.

METHOD

A retrospective, descriptive, correlational and nested 1:1 matched case-control design was used. A computerised list of patients, who underwent surgery between May 2009 and March 2015, was generated in the targeted hospital. A final bill for every selected patient was also determined. Patients were divided equally into two groups: patients with an SSI and patients without an SSI.

RESULTS

A total of 64 patients were recruited. The SSI-group had a significant higher mean health-care cost of $7,899.08 (p=0.001) and a longer stay in hospital (mean additional days: 23.17) than the non-SSI group. Furthermore, Acinetobacter baumannii and Staphylococcus aureus were determined as the most predominant causative agents of SSI, at 39.1% and 26.1% of SSI patients, respectively.

CONCLUSION

The results of this study can be considered as a baseline for national benchmarking to evaluate the quality of care provided to targeted patients. This study should encourage nurse administrators to adopt protocols and strategies that promote infection control measures, as well as to develop new methods of surveillance on universal precautions adherence. This may limit pathogen contamination in the surgical wound, shorten length of stay and decrease health-care costs.

Risk factors for surgical site infection after craniotomy: a prospective cohort study

Background

Although surgical site infection after craniotomy (SSI-CRAN) is a serious complication, risk factors for its development have not been well defined. We aim to identify the risk factors for developing SSI-CRAN in a large prospective cohort of adult patients undergoing craniotomy.

Methods

A series of consecutive patients who underwent craniotomy at a university hospital from January 2013 to December 2015 were prospectively assessed. Demographic, epidemiological, surgical, clinical and microbiological data were collected. Patients were followed up in an active post-discharge surveillance programm e for up to one year after surgery. Multivariate analysis was carried out to identify independent risk factors for SSI-CRAN.

Results

Among the 595 patients who underwent craniotomy, 91 (15.3%) episodes of SSI-CRAN were recorded, 67 (73.6%) of which were organ/space. Baseline demographic characteristics were similar among patients who developed SSI-CRAN and those who did not. The most frequent causative Gram-positive organisms were Cutibacterium acnes (23.1%) and Staphylococcus epidermidis (23.1%), whereas Enterobacter cloacae (12.1%) was the most commonly isolated Gram-negative agent. In the univariate analysis the factors associated with SSI-CRAN were ASA score > 2 (48.4% vs. 35.5% in SSI-CRAN and no SSI-CRAN respectively, p = 0.025), extrinsic tumour (28.6% vs. 19.2%, p = 0.05), and re-intervention (4.4% vs. 1.4%, p = < 0.001). In the multivariate analysis, ASA score > 2 (AOR: 2.26, 95% CI: 1.32-3.87; p = .003) and re-intervention (OR: 8.93, 95% CI: 5.33-14.96; p < 0.001) were the only factors independently associated with SSI-CRAN.

Conclusion

The risk factors and causative agents of SSI-CRAN identified in this study should be considered in the design of preventive strategies aimed to reduce the incidence of this serious complication.