Systematic Review and Meta-Analysis of Antibiotic-Impregnated Shunt Catheters on Anti-Infective Effect of Hydrocephalus Shunt

Surgical management of primary and idiopathic internal hydrocephalus in dogs and cats

Ventriculoperitoneal shunt placement is an effective method to treat internal hydrocephalus in dogs and cats. Although it has a long history in veterinary medicine, the technique continues to evolve. Despite continuing attempts to reduce the incidence of associated complications, shunt failure remains a major problem, and often leads to multiple hospital admissions. This review gives an overview about current knowledge of ventriculoperitoneal shunting techniques in animals, applicable shunt hardware as well as shunt-associated complications and their prevention and treatment.

Antibiotic-Impregnated Ventriculoperitoneal Shunts Decrease Bacterial Shunt Infection: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES

Antibiotic-impregnated shunts seem to be beneficial in preventing bacterial infections and decreasing mortality by effectively inhibiting microbial growth in the shunt system and reducing the risk of shunt-associated infections. This study aimed to evaluate the efficacy of antibiotic-impregnated shunt catheters (AISC) in reducing the incidence of bacterial shunt infection in patients with hydrocephalus.

METHODS

The protocol was registered on PROSPERO. A meta-analysis was conducted by searching 3 databases (PubMed, Scopus, CENTRAL) for relevant randomized controlled trials and observational studies. We included all studies published until November 2022 in any language. The primary outcome was the rate of bacterial infections, whereas the rate of shunt failure was our secondary endpoint. Odds ratios (OR) with 95% CI were calculated using a random-effects model.

RESULTS

A total of 27 articles with 27 266 shunt operations were included in this study. The results indicated that using AISC is significantly associated with reduction in infections (OR = 0.42; 95% CI: 0.33-0.54). Regarding shunt failure, there was a tendency in favor of AISC use (OR = 0.73; 95% CI: 0.51-1.06).

CONCLUSION

Our study provided evidence that AISC is significantly associated with the reduction in the rate of bacterial ventriculoperitoneal-shunt infection. In addition, there was a tendency toward AISC to decrease shunt failure compared with the standard shunt.

Techniques to Reduce the Rate of Infection in Surgeries for Cerebrospinal Fluid Shunting in Adults

OBJECTIVE

Cerebrospinal fluid shunt placement is associated with high rates of infection. Multiple standardized protocols, particularly in pediatric populations, have been proposed to mitigate this infection rate. We sought to determine the effectiveness of a standardized shunt infection protocol in a large adult population.

METHODS

A retrospective cohort study of adults presenting for primary cerebrospinal fluid shunt placement from 2012 to 2022. The primary outcome of interest was shunt infection. The primary exposure of interest was implementation of the shunt protocol (began October 2015). Secondary exposures of interest included use and type of perioperative antibiotics and total operating room time.

RESULTS

In total, 820 patients were included, 140 before protocol implementation and 680 after protocol implementation. The overall number of infections over the study period was 15 (1.8% infection rate), with 8 infections preprotocol (5.7%) and 7 infections during the protocol period (1.0%). The infection protocol was associated with a decreased infection rate (odds rato [OR] 0.18, 95% confidence interval [CI] 0.05-0.58, P = 0.002). Total operating room time (OR 1.38 per 30-minute increase, 95% CI 1.05-1.81, P = 0.021) was associated with increased infection rate. Patients who received antibiotics with primarily gram-positive coverage (cefazolin or equivalent) did not have significantly different odds of shunt infection as patients who received broad-spectrum coverage (OR 2.10, 95% CI 0.56-7.88, P = 0.274).

CONCLUSIONS

The implementation of an evidence-based perioperative shunt infection protocol is an effective method to decrease shunt infections. Broad-spectrum perioperative antibiotics may not have greater efficacy than gram-positive only coverage, but more research is required.

Epidemiology, clinical profile, and outcomes of CSF-diversion catheter-related infections - Prospective cohort study results from a single quaternary neurosurgery referral centre

BACKGROUND

Device-associated CNS infections is a major subgroup of healthcare associated CNS infections. Healthcare-associated ventriculitis or meningitis differs considerably from community-acquired meningitis in its epidemiology, pathogenesis, clinical presentation and management.

OBJECTIVES

This study aimed to identify the infection rates, the associated risk factors, and outcomes of these life-threatening infections.

METHODS

This was a 2-year single center prospective cohort study. Patient's clinical data, laboratory parameters, treatment and their outcomes were collected using data collection tool, and device days were collected from the hospital information system (HIS). Patients were categorised using IDSA criteria as contamination or colonisation or infection. Cox regression model was used for multivariate analysis to estimate hazard risk.

RESULTS

A total of 578 CSF diversion catheters were inserted in 472 patients. The average rate for EVD and LD infection were 11.12 and 11.86 per 1000 device days respectively. The average infection rates for VP and LP shunts were 6% and 5.2% per procedure, respectively. The commonest etiological agent causing CSF diversion catheter-related infection (CDRI) was Klebsiella pneumoniae (n = 14, 40%). The risk factors which were independently associated with increased infection risk by cox regression analysis were drain insertion ≥7 days [HR:11.73, p -0.03], posterior approach of EVD insertion (occipital) [HR:9.53, p - 0.01], pre-OP ASA score>3 [HR:8.28, p - 0.013] presence of EVD/LD leak [HR: 17.24, p < 0.0001], male gender [HR:2.05, p-0.05] and presence of associated peri-operative scalp infections [HR:3.531, p-0.005]. Shift to narrow spectrum surgical prophylactic antibiotic [Coefficient: -1.284, p-0.03] and reduction in CSF sampling frequency [Coefficient: -1.741, p-0.02] were found to be negatively associated with CDRI.

CONCLUSIONS

The study demonstrated drain insertion ≥7 days, posterior approach of EVD insertion, presence of EVD/LD leak, male gender and presence of associated peri-operative scalp skin and soft tissue infections were associated with increased risk of infection.

Is It Possible to Eliminate Postoperative Shunt Infections?: Results of a Modified Hydrocephalus Clinical Research Network Protocol

BACKGROUND

 Postoperative shunt infection is a nightmare in neurosurgical practice with additional morbidity and mortality. A lot of protocols have contributed to the reduction of ventriculoperitoneal shunt (VPS) infections but not eradication. The aim of the study was to evaluate the rigid application of a modified Hydrocephalus Clinical Research Network (HCRN) protocol in the prevention of postoperative shunt infection.

METHODS

 We retrospectively evaluated children with congenital hydrocephalus who underwent VPS insertion, and in whom the protocol was applied from June 2019 to January 2020. Follow-up ranged from 11 to 24 months.

RESULTS

 Thirty-seven procedures were performed including 35 primary shunt insertions and two revision surgeries. The median age was 5 months (range, 1-30 months), and 25 patients were males. The most common cause for VPS placement was congenital hydrocephalus without identifiable cause in 28 cases (80%). The endoscope-assisted technique was used in the insertion of the proximal end in six cases (17%). The mean follow-up was 19.4 months (11-24 months). The rate of shunt infection was 0% till the last follow-up.

CONCLUSION

 The preliminary results showed an effective method for the prevention of postoperative shunt infections using the modified protocol. These initial findings need to be validated in a large prospective study before widespread application can be recommended.

Molecular-scale insights into confined clindamycin in nanoscale pores of mesoporous silica

Clindamycin is an antibiotic used to treat a variety of bacterial infections. The sustained release of clindamycin from the drug carrier is an important strategy to prolong the effective antibacterial duration. In this work, the microstructure and dynamics of clindamycin confined into the nanopores of mesopore silica with different pore sizes were studied using molecular dynamics simulation. It is found that there is a layering behavior for clindamycin distribution as a function of distance from the pore surface to the pore center with preferred location near the surface of the nanopore. The radial distribution function between carbonyl oxygen and the silanol groups shows the highest intensity of the first peak with the preferred orientation of carbonyl oxygen pointing toward the pore surface, which suggests the strong interaction between the carbonyl oxygen and the silanol groups on the pore surface. The higher local diffusion coefficients for the clindamycin molecules near the pore surface can be found. In addition, the presence of water can lead to the shift of clindamycin distribution away from the surface and promote the local diffusion of clindamycin near the pore surface. The information in this work will provide the microscopic understanding for the design of the drug carriers for the controlled release of clindamycin.

Development of shunt valves used for treating hydrocephalus: comparison with endoscopy treatment

The pathophysiology of hydrocephalus is not clearly defined. Thus, treatment will remain empirical until a fuller understanding of the various forms of hydrocephalus is achieved. Valve-controlled shunting has been the mainstay of therapy since the late 1950s. Initially, shunting occurred from the ventricular system to the atrium. In the 1970s, VA shunts were replaced by ventriculoperitoneal shunts as the primary location for the distal end. Multiple types of one-way valve systems have been developed in the pursuit of draining the appropriate amount of CSF that avoids either overdrainage or underdrainage while preserving normal brain development and cognition. These valves are reviewed and compared as to their function. Other locations for the distal end of the shunting system are reviewed to include pleural space and gallbladder. The lumbar subarachnoid space as the proximal location for a shunt is also reviewed. The only other surgical alternative for treating hydrocephalus is endoscopic third ventriculostomy. Since 2000, approximately 50% of children with hydrocephalus have been shown to be candidates for ETV. The benefits are the lack of need for an artificial shunt system and thus lower rates of infection and over time fewer reoperations. Future progress is dependent on improved shunt valve systems that are affordable worldwide and ready availability of ETV in developing countries. Anatomic and molecular causes of hydrocephalus need to be defined so that medications or genetic modifications become available for potential cure of hydrocephalus.

Bacterial ventriculoperitoneal shunt infections: changing trends in antimicrobial susceptibility, a 7-year retrospective study from Pakistan

BACKGROUND

Ventriculoperitoneal (VP) shunt infections in adults represent a severe complication and make treatment more challenging. Therefore, drug susceptibility patterns are crucial for therapeutic decisions and infection control in neurosurgical centers. This 7-year retrospective study aimed to identify the bacteria responsible for adult VP shunt infections and determine their drug susceptibility patterns.

METHODS

This single-center study was performed from 2015 to 2021 in Lahore, Pakistan, and included CSF cultures from VP shunt infections. Demographic data, causative organisms, and antimicrobial susceptibility testing results were collected. Multivariate analysis of variance (MANOVA) and two-sample t-tests were used to analyze and compare the antibiotic sensitivity trends over the study period.

RESULTS

14,473 isolates recovered from 13,937 CSF samples of VP shunt infections were identified and analyzed for their susceptibility patterns to antimicrobials. The proportion of Gram-negative and Gram-positive bacteria were 11,030 (76%) and 3443 (24)%, respectively. The predominant bacteria were Acinetobacter species (n = 5898, 41%), followed by Pseudomonas species (n = 2368, 16%) and coagulase-negative Staphylococcus (CoNS) (n = 1880, 13%). 100% of Staphylococcus aureus (S.aureus) and CoNS were sensitive to vancomycin and linezolid (n = 2580). However, 52% of S. aureus (719/1,343) were methicillin-resistant Staphylococcus aureus (MRSA). Acinetobacter showed maximum sensitivity to meropenem at 69% (2759/4768). Pseudomonas was 80% (1385/1863 sensitive to piperacillin-tazobactam, Escherichia coli (E. coli) showed 72% to amikacin (748/1055), while Klebsiella spp. was 57% (574/1170) sensitive to piperacillin-tazobactam. The sensitivity of piperacillin-tazobactam and meropenem for Gram-negative bacteria decreased significantly (p < 0.05) over 7 years, with 92.2% and 88.91% sensitive in 2015 and 66.7% and 62.8% sensitive in 2021, respectively.

CONCLUSION

The significant decrease in the effectiveness of carbapenem and beta-lactam/beta-lactamase inhibitor combination drugs for the common Gram-negative causative agents of VP shunt infections suggests that alternative antibiotics such as colistin, fosfomycin, ceftazidime/avibactam, ceftolozane/tazobactam, and tigecycline should be considered and in consequence included in testing panels. Additionally, it is recommended to adopt care bundles for the prevention of VP shunt infection.

Gastrostomy and internal cerebrospinal fluid shunt in adults. A systematic review and meta-analysis of the risk of infection

BACKGROUND

Hydrocephalus is a frequent neurological condition, commonly treated by ventriculoperitoneal shunting (VPS), a neurosurgical procedure with significant risk of infection. Some severely brain-injured hydrocephalic patients with swallowing dysfunction may require percutaneous endoscopic gastrostomy (PEG). There are few data on the safety of PEG in patients with VPS, with contradictory results reported.

OBJECTIVE

The aim of this systematic review and meta-analysis was to determine the rate of VPS infection in the setting of PEG.

METHODS

Six databases were searched for the period January 1990 to June 2022. Only original articles reporting the rate of shunt infection in the setting of PEG in adults were included. Random-effects meta-analysis was used to assess the rate of infection.

RESULTS

Fifteen of the 1,703 identified articles were selected, reporting 701 internal cerebrospinal fluid shunts, with 63 infections. The pooled rate of infection in patients with both PEG and VPS was 7.41% (95% CI [3.67-14.38]). There was a significantly higher risk of VPS infection in the PEG group vs. the control group with VPS without PEG: relative risk (RR)=2.33 (95% CI [1.11-4.89]). On the other hand, the risk of infection was the same whether the PEG was placed before or after the VPS surgery: RR=1.05 (95% CI [0.57-1.92]).

CONCLUSION

Gastrostomy tube placement is a significant risk factor for VPS infection. However, onset of infection was not related to the sequence of or interval between VPS and PEG.

TRIAL REGISTRATION

This meta-analysis is registered in https://www.crd.york.ac.uk/PROSPERO/, PROSPERO ID: CRDCRD42022326774.