Cerebrospinal fluid shunt infections in children over a 13-year period: anaerobic cultures and comparison of clinical signs of infection with Propionibacterium acnes and with other bacteria

Cerebrospinal Fluid Shunt Reinfection and Malfunction in Ecuadorian Children with Different Reshunting Criteria After Infection. "Is It Just One Shunt After Another?"

OBJECTIVE

There is no firm evidence regarding cerebrospinal fluid (CSF) shunt reimplantation after infection in the pediatric population. The purpose of this study was to compare different criteria and analyze new shunt failure.

METHODS

A cross-sectional retrospective multicenter study was performed over 6 years to study patients and each infected shunt at diagnosis, reimplantation, and after reimplantation. The patients were divided into 2 groups: group 1 (G1), reimplantation after negative serial CSF cultures during antibiotic treatment; group 2 (G2), reimplantation after negative serial pancultures after completion of antibiotics. The differences were measured with Mann-Whitney and Χ2 tests; multivariate analysis and associations were calculated using odds ratios (ORs) based on logistic regression.

RESULTS

There were 137 shunt infection events in 110 patients: 28 events in G1 and 109 in G2. Significant differences were observed in the diagnosis and reimplantation. Reimplantation dysfunction in G1 was 16 (55.17%) versus 30 (27.78%) in G2 (P = 0.006). The risk of shunt malfunction after reimplantation increased for G1 reimplantation criteria (P = 0.018; OR, 3.34; confidence interval [CI], 1.23-9.05): pleocytosis at diagnosis >17 cells (P = 0.036; OR, 2.41; CI, 1.06-5.47), CSF proteins at diagnosis >182 mg/dL (P = 0.049; OR, 2.21; CI, 1.00-4.89).

CONCLUSIONS

G2 reimplantation criteria were related to improved pleocytosis, CSF proteins, and blood neutrophils compared with G1. Mechanical and infectious dysfunction of the new shunt was 3 times more prevalent in G1 than in G2, considering the differences between the groups at diagnosis. Increased parameters of infection at diagnosis were associated with future malfunction more than parameters before reimplantation in both groups.

Measurement of cerebrospinal fluid lactate levels in pediatric patients with suspected ventriculoperitoneal shunt infection: A retrospective cohort study

INTRODUCTION

Ventriculoperitoneal shunt (VPS) infection is a severe complication. Early diagnosis could help to decrease morbidity and treatment costs. Lactate has been used for the diagnosis of other central nervous system infections. The aim of this study is to determine the usefulness of lactate for the diagnosis of VPS infection.

METHODOLOGY

Retrospective cohort study. Lactate was measured in patients who consulted with VPS dysfunction between May 2019 and May 2022. Mean were compared according to culture results. A Receiver Operating Characteristic (ROC) curve was performed to determine the appropriate cut-off point.

RESULT

Lactate has a high negative predictive value but a low positive predictive value for the diagnosis of ventriculitis.

Cerebrospinal fluid shunt infections in children

Cerebrospinal fluid (CSF) shunts are commonly used for the long-term management of hydrocephalus in children. Shunt infection remains a common complication, occurring in about 5%-15% of CSF shunts. This narrative review summarises key evidence from recent literature on the epidemiology, pathogenesis, clinical presentation, diagnosis, management, outcomes and prevention of CSF shunt infections in children. The majority of shunt infections occur due to contamination at the time of surgery, with coagulase-negative staphylococci and Staphylococcus aureus being the most common infecting organisms. Clinical presentations of shunt infection can be varied and difficult to recognise. CSF cultures are the primary test used for diagnosis. Other CSF and blood parameters may aid in diagnosis but lack sensitivity and specificity. Core aspects of management of shunt infections include systemic antimicrobial therapy and surgical removal of the shunt. However, many specific treatment recommendations are limited by a lack of robust evidence from large studies or controlled trials. Shunt infections may result in long hospital stays, worsening hydrocephalus, neurological sequelae and other complications, as well as death. Therefore, reducing the incidence of infection and optimising management are high priorities. Antibiotic prophylaxis at the time of shunt placement, improved surgical protocols and antibiotic-impregnated shunts are key strategies to prevent shunt infections. Nevertheless, further work is needed to identify additional strategies to prevent complications and improve outcomes.

Indian Society of Pediatric Neurosurgery Consensus Guidelines on Preventing and Managing Shunt Infection: Version 2020-21

Background

Shunt infection is the most significant morbidity associated with shunt surgery. Based on the existing literature for the prevention and management of shunt infection, region and resource-specific recommendations are needed.

Methods

In February 2020, a Guidelines Development Group (GDG) was created by the Indian Society of Paediatric Neurosurgery (IndSPN) to formulate guidelines on shunt infections, which would be relevant to our country and LMIC in general. An initial email survey identified existing practices among the membership of the IndSPN, and eight broad issues pertaining to shunt infection were identified. Next, members of the GDG performed a systematic review of the literature on the prevention and management of shunt infection. Then, through a series of virtual meetings of the GDG over 1 year, evidence from the literature was presented to all the members and consensus was built on different aspects of shunt infection. Finally, the guidelines document was drafted and circulated among the GDG for final approval. Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to grade the evidence and strength of recommendation.

Results

The guidelines are divided into eight sections. Level I and Level II evidence was available for only five recommendations and led to a moderate level of recommendations. Most of the available evidence was at Level III and below, and hence the level of recommendation was low or very low. A consensus method was used to provide recommendations for several issues.

Conclusions

Although most of the recommendations for the prevention and management of shunt infections are based on a low level of evidence, we believe that this document will provide a useful reference to neurosurgeons not only in India but also in other low and middle income countries. These guidelines need to be updated as and when new evidence emerges.

Cutibacterium acnes Central Nervous System Catheter Infection Induces Long-Term Changes in the Cerebrospinal Fluid Proteome

Cutibacterium acnes is the third most common cause of cerebrospinal fluid (CSF) shunt infection and is likely underdiagnosed due to the difficulty in culturing this pathogen. Shunt infections lead to grave neurologic morbidity for patients especially when there is a delay in diagnosis. Currently, the gold standard for identifying CSF shunt infections is microbiologic culture. However, C. acnes infection often results in falsely negative cultures; therefore, new diagnostic methods are needed. To investigate potential CSF biomarkers of C. acnes CSF shunt infection we adapted a rat model of CSF catheter infection to C. acnes. We found elevated levels of interleukin-1β (IL-1β), IL-6, chemokine ligand 2, and IL-10 in the CSF and brain tissues of animals implanted with C. acnes-infected catheters compared to sterile controls at day 1 postinfection. This coincided with modest increases in neutrophils in the CSF and, to a greater extent, in the brain tissues of animals with C. acnes infection, which closely mirrors the clinical findings in patients with C. acnes shunt infection. Mass spectrometry revealed that the CSF proteome is altered during C. acnes shunt infection and changes over the course of disease, typified at day 1 postinfection by an acute-phase and pathogen neutralization response evolving to a response consistent with wound resolution at day 28 compared to a sterile catheter placement. Collectively, these results demonstrate that it is possible to distinguish C. acnes infection from sterile postoperative inflammation and that CSF proteins could be useful in a diagnostic strategy for this pathogen that is difficult to diagnose.

Recurrent Shoulder Tip Pain After Ventriculoperitoneal Shunt Placement Associated with Infectious Peritonitis with Propionibacterium acnes; A Case Report and Review of the Literature

Ventriculoperitoneal (VP) shunt placement is commonly performed for the treatment of hydrocephalus, and several complications of this procedure are well known. Radiating shoulder tip pain after VP shunt placement has been reported as an unusual complication in a few cases, associated with dislocation of the peritoneal catheter. We described the case of a 9-year-old girl who presented with recurrent radiating shoulder tip pain after VP shunt placement. The pain recurred after peritoneal catheter repositioning because of peritoneal inflammation and adhesion due to peritonitis with Propionibacterium acnes (P. acnes). This bacterium was isolated using 16S ribosomal RNA gene polymerase chain reaction (16S rRNA gene PCR), and anaerobic and prolonged culture tests. After antibacterial treatment, ventriculoarterial (VA) shunt placement was successfully performed. Hemidiaphragm irritation by the peritoneal catheter leads to radiating shoulder tip pain, and peritoneal inflammation and adhesion caused by infectious peritonitis may cause recurrence of this despite catheter repositioning. Clinicians should be aware of shoulder pain as a complication of VP shunt placement, and should consider VA shunt placement as an alternative treatment if this symptom recurs after catheter repositioning. Furthermore, 16S rRNA gene PCR and anaerobic and prolonged culture tests should be considered to detect P. acnes infection.

Abdominal pseudocysts, an unusual complication of ventriculoperitoneal shunt systems: Literature systematic review

Since the first report in 1954, abdominal pseudocysts have been recognized as a particularly uncommon complication of ventriculoperitoneal shunts of CSF, so their etiology, diagnosis, and therapeutic management remain very controversial. Our objective is to offer a critical and updated systematic review of those controversial points, using a thorough search and review of the most relevant literature available. The clinical presentation of pseudocysts is normally through non-specific abdominal symptoms. The most validated etiology consists on the existence of a concomitant infection of the CSF shunt system, and so, treatment needs of antibiotherapy and total or partial substitution of the system. However, the pseudocyst itself doesn't need an active treatment, except for some specific cases. This management, algorithmically presented in the present work, achieves a lower recurrence rate than other options, but this one is still important, and is also associated with other complications of those shunts related with several other factors which need to be taken in account.

Suprahepatic space as an alternative site for distal catheter insertion in pseudocyst-associated ventriculoperitoneal shunt malfunction

OBJECTIVE

Distal catheter malfunction due to pseudocyst formation or intraabdominal adhesion is a significant problem, especially in pediatric patients who have limited sites for distal catheter insertion. In this study, the authors present a series of 12 patients with intractable distal shunt malfunctions due to peritoneal pseudocyst formation who underwent distal catheter replacement in the suprahepatic space to reduce the risk of distal catheter malfunction.

METHODS

Twelve consecutive patients with shunt malfunction due to pseudocyst formation who had undergone ventriculosuprahepatic shunting from 2014 to 2019 were identified. According to medical records, after primary evaluations, shunt removal, and antibiotic therapy, they underwent revision surgeries with placement of a distal catheter into the suprahepatic space.

RESULTS

Nine boys and 3 girls, ranging in age from 5 months to 14 years, with one or more episodes of pseudocyst formation, underwent shunt revision with placement of a distal catheter into the suprahepatic space. After a median follow-up of 31 months, none of the patients experienced further distal malfunction.

CONCLUSIONS

The suprahepatic space appears to be a safe place to secure the distal end of a ventricular catheter following pseudocyst formation, with less risk of re-adhesion. This lower risk might be attributable to the lack of omentum in the suprahepatic space.

Evaluation of an in vivo model for ventricular shunt infection: a pilot study using a novel antimicrobial-loaded polymer

OBJECTIVE

Ventricular shunt infection remains an issue leading to high patient morbidity and cost, warranting further investigation. The authors sought to create an animal model of shunt infection that could be used to evaluate possible catheter modifications and innovations.

METHODS

Three dogs underwent bilateral ventricular catheter implantation and inoculation with methicillin-sensitive Staphylococcus aureus (S. aureus). In 2 experimental animals, the catheters were modified with a polymer containing chemical "pockets" loaded with vancomycin. In 1 control animal, the catheters were polymer coated but without antibiotics. Animals were monitored for 9 to 11 days, after which the shunts were explanted. MRI was performed after shunt implantation and prior to catheter harvest. The catheters were sonicated prior to microbiological culture and also evaluated by electron microscopy. The animals' brains were evaluated for histopathology.

RESULTS

All animals underwent successful catheter implantation. The animals developed superficial wound infections, but no neurological deficits. Imaging demonstrated ventriculitis and cerebral edema. Harvested catheters from the control animal demonstrated > 104 colony-forming units (CFUs) of S. aureus. In the first experimental animal, one shunt demonstrated > 104 CFUs of S. aureus, but the other demonstrated no growth. In the second experimental animal, one catheter demonstrated no growth, and the other grew trace S. aureus. Brain histopathology revealed acute inflammation and ventriculitis in all animals, which was more severe in the control.

CONCLUSIONS

The authors evaluated an animal model of ventricular shunting and reliably induced features of shunt infection that could be microbiologically quantified. With this model, investigation of pathophysiological and imaging correlates of infection and potentially beneficial shunt catheter modifications is possible.

Relationship of causative organism and time to infection among children with cerebrospinal fluid shunt infection

OBJECTIVE

Infection is a common complication of cerebrospinal fluid (CSF) shunts, occurring in 6%-20% of children. Although studies are limited, Staphylococcus aureus is thought to cause more rapid and aggressive infection than coagulase-negative Staphylococcus (CONS) or gram-negative organisms. The authors' objective was to evaluate the relationship between the causative organisms of CSF shunt infection and the timing of infection.

METHODS

The authors performed a retrospective cohort study of children who underwent CSF shunt placement at a tertiary care children's hospital over a 9-year period and subsequently developed a CSF shunt infection. The primary predictor variable was the causative organism recovered from CSF culture, characterized as S. aureus, CONS, or gram-negative organisms. The primary outcome was time to infection, defined as the number of days from most recent shunt intervention to the diagnosis of the infection. The association between causative organism and time to infection was visualized using Kaplan-Meier curves, and statistical comparisons were made using nonparametric Kruskal-Wallis tests.

RESULTS

Among 103 children in whom a CSF shunt infection developed, the causative organism was CONS in 57 (55%), S. aureus in 19 (18%), and gram-negative organisms in 9 (9%). The median time to infection did not differ (p = 0.81) for infections caused by CONS (20 days, IQR 11-40), S. aureus (26 days, IQR 12-95), and gram-negative organisms (23 days, IQR 17-34).

CONCLUSIONS

No significant difference in time to infection based on the causative organism was observed among children with a CSF shunt infection.

Neutrophil CD64 index in cerebrospinal fluid as a marker of bacterial ventriculitis in children with external ventricular drainage

Background

Bacterial ventriculitis is a common complication in children with temporary external ventricular drains (EVD) and the diagnosis is challenging. The present study compared the diagnostic accuracy of novel cerebrospinal fluid (CSF) marker - CD64 expression on neutrophils measured as neutrophil CD64 index (CD64in) to routine laboratory CSF and blood markers for bacterial ventriculitis in children with EVD.

Methods

We conducted a prospective, observational study, enrolling children with EVD. CD64in in CSF together with CSF markers (leukocyte count, percentage of neutrophils, glucose, and proteins) and blood markers (leukocyte and differential count, C-reactive protein (CRP), and procalcitonin (PCT)) were studied at the time of suspected bacterial ventriculitis. CD64in was measured by flow cytometry. Diagnostic accuracy determined by the area under the receiver–operating characteristic (ROC) curves (AUC) was defined for each marker.

Results

Thirty-three episodes of clinically suspected ventriculitis in twenty-one children were observed during a 26-month period. Episodes were classified into those with microbiologically proven ventriculitis (13 episodes) and into those with microbiologically negative CSF (20 episodes). CD64in and leukocyte count were the only CSF markers that could differentiate between groups with diagnostic accuracy of 0.875 and 0.694, respectively. Among blood markers only CRP and band neutrophils differentiated between groups with diagnostic accuracy of 0.792 and 0.721, respectively.

Conclusions

CD64in in CSF is a promising diagnostic marker of bacterial ventriculitis in children with EVD as it has higher diagnostic accuracy than routine blood and CSF markers for diagnosing bacterial ventriculitis at the time of clinical suspicion.

Propionibacterium acnes Infection in Disc Material and Different Antibiotic Susceptibility in Patients With Lumbar Disc Herniation

BACKGROUND

Low back pain is an important, worldwide clinical problem from which human populations are suffering. It has been suggested that Propionibacterium acnes is associated with low back pain. The objective of this clinical study is to evaluate the P. acnes infection in the disc material and antibiotic susceptibility in patients with disc herniation.

METHODS

A total of 120 patients with disc herniation surgery were enrolled in the study. The samples were excited during discectomy and then cultured in both anaerobic and aerobic incubations. Minimum inhibitory concentration (MIC) was performed for determination of antibiotic susceptibility.

RESULTS

Of 120 samples, 60 (50%) samples were positive for microorganisms. Disc herniation was at the level of L4-L5 in 63 cases and L5-S1 in 57 cases.

CONCLUSIONS

According to the results and presence of P. acnes in more than 35% of the cultured samples, the presence of P. acnes in lumbar disc herniation is a suspected element leading to this condition. After analysis of the antibiotics, the lowest MIC value was identified for amoxicillin, ciprofloxacin, erythromycin, rifampicin, tetracycline, vancomycin; the moderate MIC value was for fusidic acid; and the highest MIC value was for gentamicin and trimethoprim.

Diagnostic Approach to Health Care- and Device-Associated Central Nervous System Infections

Health care- and device-associated central nervous system (CNS) infections have a distinct epidemiology, pathophysiology, and microbiology that require a unique diagnostic approach. Most clinical signs, symptoms, and tests used to diagnose community-acquired CNS infections are insensitive and nonspecific in neurosurgical patients due to postsurgical changes, invasive devices, prior antimicrobial exposure, and underlying CNS disease. The lack of a standardized definition of infection or diagnostic pathway has added to this challenge. In this review, we summarize the epidemiology, microbiology, and clinical presentation of these infections, discuss the issues with existing microbiologic tests, and give an overview of the current diagnostic approach.

Analysis of Codman microcerebrospinal fluid shunt

INTRODUCTION

Ventriculo-peritoneal cerebrospinal fluid (CSF) shunt is the most common method of treating pediatric hydrocephalus. The Codman microadjustable valve (CMAV) is a CSF shunt constructed for children. The objective of the study was (a) to analyze complications after insertion of a CMAV shunt in hydrocephalic children, (b) to analyze complications after replacing a CMAV by an adult-type Codman Hakim adjustable valve shunt (CHAV), and to (c) analyze the in vitro characteristics of the CMAV shunt and correlate the findings with the clinical performance of the shunt.

METHODS

A retrospective study analyzed a cohort of hydrocephalic children who had received a CMAV shunt and later replaced by a CHAV shunt. We report on the complications that resulted from replacing the CMAV with the CHAV. We tested six CMAV shunts with or without an antisiphon device (ASD) in which opening pressure, resistance, sensitivity to abdominal pressure, ASD position dependency, and function were determined. The test results were correlated with the clinical performance of the shunt in the retrospective study.

RESULTS

Thirty-seven children (19 boys, 18 girls) were identified. Within the first month after shunt placement, a total of 10 patients (27%) developed complications including infections, hygromas, and shunt dysfunction. Shunt survival varied from 1 week to 145 months. Over the 10-year follow-up period, 13 children had their shunts replaced, six of them with a CHAV without any further complications. A bench test of the CMAV was done to test whether the opening pressure was in agreement with the manufacturer's specifications. Our results were generally in agreement with specifications stated by the manufacturer.

CONCLUSION

Replacing a CMAV with a CHAV was well tolerated by the patients. Bench test results were generally in agreement with manufacturers specifications. Replacing a CMAV with a CHAV in pediatric hydrocephalus patients can be accomplished safely.

Shunt Devices for Neurointensivists: Complications and Management

Cerebrospinal fluid diversion has become the mainstay treatment in hydrocephalus for over 50 years. As the number of patients with ventricular shunt systems increases, neurointensivists are becoming the first-line physicians for many of these patients. When symptoms of a shunt malfunction are suspected and access to a neurosurgeon is limited or delayed, workup and temporizing measures must be initiated. The article highlights the functional nuances, complications, and management of current programmable shunt valves and their MRI sensitivity.

Propionibacterium Acnes: Cause of Cerebrospinal Fluid Shunt Infection

Infection after implantation of ventriculo-peritoneal shunts is associated with significant morbidity and mortality. We describe a 9-year-old girl with Propionibacterium acnes shunt infection with negative cerebrospinal fluid cultures, diagnosed by broad-range 16S-rRNA gene polymerase chain reaction. This case supports the use of this molecular diagnostic technique in shunt infections, where the offending pathogens are difficult to culture using traditional methods.

The distribution of infection with Propionibacterium acnes is equal in patients with cervical and lumbar disc herniation

BACKGROUND

Cervical and back pains are important clinical problems affecting human populations globally. It is suggested that Propionibacterium acnes (P. acnes) is associated with disc herniation. The aim of this study is to evaluate the distribution of P. acnes infection in the cervical and lumbar disc material obtained from patients with disc herniation.

METHODS AND MATERIAL

A total of 145 patients with mean age of 45.21 ± 11.24 years who underwent micro-discectomy in cervical and lumbar regions were enrolled into the study. The samples were excited during the operation and then cultured in the anaerobic incubations. The cultured P. acnes were detected by 16S rRNA-based polymerase chain reaction.

RESULTS

In this study, 145 patients including 25 cases with cervical and 120 cases with lumbar disc herniation were enrolled to the study. There was no significant difference in the age of male and female patients (p = 0.123). P. acnes infection was detected in nine patients (36%) with cervical disc herniation and 46 patients (38.3%) with lumbar disc herniation and no significant differences were reported in P. acnes presence according to the disc regions (p = 0.508.). Moreover, there was a significant difference in the presence of P. acnes infection according to the level of lumbar disc herniation (p = 0.028).

CONCLUSION

According to the results, the presence of P. acnes is equal in patients with cervical and lumbar disc herniation. There was a significant difference in the distribution of P. acnes infection according to level of lumbar disc herniation.

LEVEL OF EVIDENCE

II.

Risk of failure in pediatric ventriculoperitoneal shunts placed after abdominal surgery

OBJECTIVE Experience has led us to suspect an association between shunt malfunction and recent abdominal surgery, yet information about this potential relationship has not been explored in the literature. The authors compared shunt survival in patients who underwent abdominal surgery to shunt survival in our general pediatric shunt population to determine whether such a relationship exists. METHODS The authors performed a retrospective review of all cases in which pediatric patients underwent ventriculoperitoneal shunt operations at their institution during a 7-year period. Survival time in shunt operations that followed abdominal surgery was compared with survival time of shunt operations in patients with no history of abdominal surgery. Univariate and multivariate analyses were used to identify factors associated with failure. RESULTS A total of 141 patients who underwent 468 shunt operations during the period of study were included; 107 of these 141 patients had no history of abdominal surgery and 34 had undergone a shunt operation after abdominal surgery. Shunt surgery performed more than 2 weeks after abdominal surgery was not associated with time to shunt failure (p = 0.86). Shunt surgery performed within 2 weeks after abdominal surgery was associated with time to failure (adjusted HR 3.6, 95% CI 1.3-9.6). CONCLUSIONS Undergoing shunt surgery shortly after abdominal surgery appears to be associated with shorter shunt survival. When possible, some patients may benefit from shunt placement utilizing alternative termini.

2017 Infectious Diseases Society of America's Clinical Practice Guidelines for Healthcare-Associated Ventriculitis and Meningitis

The Infectious Diseases Society of America (IDSA) Standards and Practice Guidelines Committee collaborated with partner organizations to convene a panel of 10 experts on healthcare-associated ventriculitis and meningitis. The panel represented pediatric and adult specialists in the field of infectious diseases and represented other organizations whose members care for patients with healthcare-associated ventriculitis and meningitis (American Academy of Neurology, American Association of Neurological Surgeons, and Neurocritical Care Society). The panel reviewed articles based on literature reviews, review articles and book chapters, evaluated the evidence and drafted recommendations. Questions were reviewed and approved by panel members. Subcategories were included for some questions based on specific populations of patients who may develop healthcare-associated ventriculitis and meningitis after the following procedures or situations: cerebrospinal fluid shunts, cerebrospinal fluid drains, implantation of intrathecal infusion pumps, implantation of deep brain stimulation hardware, and general neurosurgery and head trauma. Recommendations were followed by the strength of the recommendation and the quality of the evidence supporting the recommendation. Many recommendations, however, were based on expert opinion because rigorous clinical data are not available. These guidelines represent a practical and useful approach to assist practicing clinicians in the management of these challenging infections.

Modic changes in the adjacent vertebrae due to disc material infection with Propionibacterium acnes in patients with lumbar disc herniation

INTRODUCTION

Modic changes (MCs) in vertebral bones are induced by two mechanisms of mechanical factors and infection. As Propionibacterium acnes (P. acnes) have been reported to be associated with LBP. The aim of this study is to evaluate the MCs in patients with disc herniation and positive for P. acnes.

METHODS AND MATERIAL

A total of 120 patients with disc herniation surgery were enrolled into the study. The samples were excised during discectomy and then cultured in both anaerobic and aerobic incubations. Gram staining was employed for investigation of all colonies. The cultured P. acnes were detected by 16S rRNA-based polymerase chain reaction (PCR). MCs of baseline MRI were evaluated.

RESULTS

In this study, 120 subjects (69 male and 51 female) with mean age of 43.15 ± 12.62 years were investigated. Sixty disc samples and eight muscle samples were positive for microorganisms. Moreover, 16S rDNA gene was identified in 46 (38.3%) disc samples. Moreover, 36/46 patients with P. acnes in their sample had MCs.

CONCLUSION

According to the results and presence of 36/46 MCs in patients with lumbar disc herniation, positive for P. acnes suggests that P. acnes can lead to edema on the vertebrae endplates near to infected area.

Rapid diagnosis of Propionibacterium acnes infection in patient with hyperpyrexia after hematopoietic stem cell transplantation by next-generation sequencing: a case report

Background

The rapid determination of pathogenic agent is very important to clinician for guiding their clinical medication. However, current diagnostic methods are of limitation in many aspects, such as detecting range, time-consuming, specificity and sensitivity. In this report, we apply our new-developing pathogen detection method to clarify that Propionibacterium acnes is the causative agent of a two-year-old boy with juvenile myelomonocytic leukemia presenting clinical symptoms including serious rash and hyperpyrexia while traditional clinical methods of diagnosis fail to detect the pathogenic agent and multiple antimicrobial drugs are almost ineffective Propionibacterium acnes is confirmed to be the infectious agent by quantitative real-time polymerase chain reaction.

Case presentation

After haploidentical hematopoietic stem cell transplantation, a two-year-old boy with juvenile myelomonocytic leukemia presented to a pediatrist in a medical facility with hyperpyrexia and red skin rash which later changed to black skin rash all over his body. Traditional diagnostic assays were unrevealing, and several routine antimicrobial treatments were ineffective, including the vancomycin, meropenem, tobramycin, cefepime and rifampin. In this case, pediatrist resorted to the next-generation sequencing technology for uncovering potential pathogens so as to direct their use of specific drugs against pathogenic bacteria. Therefore, based on the BGISEQ100 (Ion Proton System) which performed sequencing-by-synthesis, with electrochemical detection of synthesis, and each such reaction coupled to its own sensor, which are in turn organized into a massively parallel sensor array on a complementary metal-oxidesemiconductor chip, we detect and identify the potential pathogens. As a result, we detected a significantly higher abundance of skin bacteria Propionibacterium acnes in patient’s blood than controls. It had been reported that patients infected by Propionibacterium acnes almost always had history of immunodeficiency, trauma or surgery. Considering this possible cause, antimicrobial treatment was adjusted to target this rare opportunistic pathogen. Fever and black skin rashes were rapidly reduced after administrating specific drugs against Propionibacterium acnes.

Conclusion

This case showed our new-developing pathogen detection method was a powerful tool in assisting clinical diagnosis and treatment. And it should be paid more attention to Propionibacterium acnes infection in clinical cases.

Microbial diversity on intravascular catheters from paediatric patients

Microorganisms play important roles in intravascular catheter (IVC)-related infections, which are the most serious complications in children with IVCs, leading to increased hospitalisation, intensive care admissions, extensive antibiotic treatment and mortality. A greater understanding of bacterial communities is needed in order to improve the management of infections. We describe here the systematic culture-independent evaluation of IVC bacteriology in IVC biofilms. Twenty-four IVC samples (six peripherally inserted central catheters, eight central venous catheters and ten arterial catheters) were collected from 24 paediatric patients aged 0 to 14 years old. Barcoded amplicon libraries produced from genes coding 16S rRNA and roll-plate culture methods were used to determine the microbial composition of these samples. From a total of 1,043,406 high-quality sequence reads, eight microbial phyla and 136 diverse microbial genera were detected, separated into 12,224 operational taxonomic units (OTUs). Three phyla (Actinobacteria, Firmicutes and Proteobacteria) predominate the microorganism on the IVC surfaces, with Firmicutes representing nearly half of the OTUs found. Among the Firmicutes, Staphylococcus (15.0% of 16S rRNA reads), Streptococcus (9.6%) and Bacillus (6.1%) were the most common. Community composition did not appear to be affected by patients' age, gender, antibiotic treatment or IVC type. Differences in IVC microbiota were more likely associated with events arising from catheter dwell time, rather than the type of IVC used.

Pathogenesis, clinical course and neuro-radiological signs of Proprionibacterium acnes cerebritis: Case report and literature review

The clinical and neuroimaging characteristics of brain infections related to Propionibacterium acnes are not well-characterized, making early diagnosis and treatment a challenge. More recently, life-threatening central nervous system infections with P. acnes are being reported with increasing frequency as complications of neurointerventional procedures. We present a rare case of P. acnes cerebritis that occurred as a sequela of bare platinum aneurysm coiling and a contaminant of percutaneous angiographic intervention. We include an extensive review of the literature describing the pathogenesis of P. acnes and neuro-radiological signs of brain infections related to this pathogen.

Propionibacterium acnes: from commensal to opportunistic biofilm-associated implant pathogen

Propionibacterium acnes is known primarily as a skin commensal. However, it can present as an opportunistic pathogen via bacterial seeding to cause invasive infections such as implant-associated infections. These infections have gained more attention due to improved diagnostic procedures, such as sonication of explanted foreign materials and prolonged cultivation time of up to 14 days for periprosthetic biopsy specimens, and improved molecular methods, such as broad-range 16S rRNA gene PCR. Implant-associated infections caused by P. acnes are most often described for shoulder prosthetic joint infections as well as cerebrovascular shunt infections, fibrosis of breast implants, and infections of cardiovascular devices. P. acnes causes disease through a number of virulence factors, such as biofilm formation. P. acnes is highly susceptible to a wide range of antibiotics, including beta-lactams, quinolones, clindamycin, and rifampin, although resistance to clindamycin is increasing. Treatment requires a combination of surgery and a prolonged antibiotic treatment regimen to successfully eliminate the remaining bacteria. Most authors suggest a course of 3 to 6 months of antibiotic treatment, including 2 to 6 weeks of intravenous treatment with a beta-lactam. While recently reported data showed a good efficacy of rifampin against P. acnes biofilms, prospective, randomized, controlled studies are needed to confirm evidence for combination treatment with rifampin, as has been performed for staphylococcal implant-associated infections.

What is the risk of infecting a cerebrospinal fluid-diverting shunt with percutaneous tapping?

OBJECT

Most CSF-diverting shunt systems have an access port that can be percutaneously tapped. Tapping the shunt can yield valuable information as to its function and whether an infection is present. The fear of causing a shunt infection by tapping may limit the physician's willingness to do so. The authors of this study investigate the risk of infecting a shunt secondary to percutaneous tapping.

METHODS

Following institutional review board approval, CSF specimens obtained from tapping an indwelling CSF-diverting shunt during the 2011 and 2012 calendar years were identified and matched with clinical information. A culture-positive CSF sample was defined as an infection. If results were equivocal, such as a broth-only-positive culture, a repeat CSF specimen was examined. The CSF was obtained by tapping the shunt access port with a 25-gauge butterfly needle after prepping the unshaven skin with chlorhexidine.

RESULTS

During the study period, 266 children underwent 542 shunt taps. With 541 taps, no clinical evidence of a subsequent shunt infection was found. One child's CSF went from sterile to infected 11 days later; however, this patient had redness along the shunt tract at the time of the initial sterile tap.

CONCLUSIONS

The risk of infection from tapping a shunt is remote if the procedure is done correctly.

Routine testing for anaerobic bacteria in cerebrospinal fluid cultures improves recovery of clinically significant pathogens

In North America, the widespread use of vaccines targeting Haemophilus influenzae type b and Streptococcus pneumoniae have dramatically altered the epidemiology of bacterial meningitis, while the methodology for culturing cerebrospinal fluid (CSF) specimens has remained largely unchanged. The aims of this study were 2-fold: to document the current epidemiology of bacterial meningitis at a tertiary care medical center and to assess the clinical utility of routinely querying for anaerobes in CSF cultures. To that end, we assessed CSF cultures submitted over a 2-year period. A brucella blood agar (BBA) plate, incubated anaerobically for 5 days, was included in the culture procedure for all CSF specimens during the second year of evaluation. In the pre- and postimplementation years, 2,353 and 2,302 CSF specimens were cultured, with 49 and 99 patients having positive culture results, respectively. The clinical and laboratory data for patients with positive cultures were reviewed. Anaerobic bacteria were isolated in the CSF samples from 33 patients post-BBA compared to two patients pre-BBA (P = 0.01). The anaerobic isolates included Bacteroides thetaiotaomicron (n = 1), Propionibacterium species (n = 15), and Propionibacterium acnes (n = 19) isolates; all of these isolates were recovered on the BBA. Eight of the 35 patients from whom anaerobic organisms were isolated received antimicrobial therapy. Although six of these patients had central nervous system hardware, two patients did not have a history of a neurosurgical procedure and had community-acquired anaerobic bacterial meningitis. This study demonstrates that the simple addition of an anaerobically incubated BBA to the culture of CSF specimens enhances the recovery of clinically significant anaerobic pathogens.

Effect of introduction of antibiotic-impregnated shunt catheters on cerebrospinal fluid shunt infection in children: a large single-center retrospective study

OBJECT

Infection after both primary and revision shunt surgeries remains a major problem in pediatric neurosurgical practice. Antibiotic-impregnated shunt (AIS) tubing has been proposed to reduce infection rates. The authors report their experience with AIS catheters in their large pediatric neurosurgery department.

METHODS

The authors conducted a retrospective case review of consecutive shunt operations performed before (1993-2003) and after (2005-2009) introduction of AIS tubing, with analysis of shunt infection rates and causative organisms identified.

RESULTS

The historical control group consisted of 1592 consecutive shunt operations (657 primary insertions), and the AIS study group consisted of 500 consecutive shunt operations (184 primary insertions). Patients ranged in age from 0-17 years. In the historical group, 135 infections were identified (8.4%). In the AIS study group, 25 infections were identified (5%), representing a significant reduction (p < 0.005). The latency to diagnosis of infection was 23 days in the historical group and 139 days in the AIS study group. The infection rates in infants 0-6 months of age were 12.2% (historical group) and 6.7% (AIS group, p < 0.005), and in infants 7-12 months of age the rates were 7.9% (historical group) and 2.7% (AIS group, p < 0.005). In the historical control group, the frequency rank order of causative organisms was coagulase-negative staphylococcus (51.9%), Staphylococcus aureus (31.6%), streptococcus or enterococcus spp. (8.8%), gram-negative organisms (4.4%), and Propionibacterium acnes (2.2%). Organisms responsible for infections in AIS were S. aureus (40%), followed by streptococcus or enterococcus spp. (20%), P. acnes and coagulase-negative staphylococcus (both 16%), and gram-negative organisms (4%). No unusually antibiotic-resistant bacteria were identified in either group. The authors further subdivided the AIS group into those undergoing primary AIS insertion (Subgroup 1), those undergoing revision of non-AIS systems using AIS components (Subgroup 2), and those undergoing revision of AIS systems using AIS components (Subgroup 3). Infection rates were 1.6% in Subgroup 1, 2.5% in Subgroup 2, and 11.7% in Subgroup 3. Staphylococcus aureus was the most common organism identified in infections of the Subgroups 2 and 3.

CONCLUSIONS

Use of AIS tubing significantly improves shunt infection rates in both general pediatric and infant populations with no evidence of increased antibiotic resistance, which is in agreement with previous studies. However, the increased infection rate in revision surgery in children with AIS catheters in situ raises questions about their long-term application.

Genotypic and antimicrobial characterisation of Propionibacterium acnes isolates from surgically excised lumbar disc herniations

The anaerobic skin commensal Propionibacterium acnes is an underestimated cause of human infections and clinical conditions. Previous studies have suggested a role for the bacterium in lumbar disc herniation and infection. To further investigate this, five biopsy samples were surgically excised from each of 64 patients with lumbar disc herniation. P. acnes and other bacteria were detected by anaerobic culture, followed by biochemical and PCR-based identification. In total, 24/64 (38%) patients had evidence of P. acnes in their excised herniated disc tissue. Using recA and mAb typing methods, 52% of the isolates were type II (50% of culture-positive patients), while type IA strains accounted for 28% of isolates (42% patients). Type III (11% isolates; 21% patients) and type IB strains (9% isolates; 17% patients) were detected less frequently. The MIC values for all isolates were lowest for amoxicillin, ciprofloxacin, erythromycin, rifampicin, tetracycline, and vancomycin (≤1mg/L). The MIC for fusidic acid was 1-2 mg/L. The MIC for trimethoprim and gentamicin was 2 to ≥4 mg/L. The demonstration that type II and III strains, which are not frequently recovered from skin, predominated within our isolate collection (63%) suggests that the role of P. acnes in lumbar disc herniation should not be readily dismissed.

Significant reduction of shunt infection rate in children below 1 year of age after implementation of a perioperative protocol

BACKGROUND

Shunt infection markedly impairs the clinical result of shunt surgery. The infection rate can be reduced by dedicated protocols. This study was undertaken to determine the efficacy of introducing a perioperative protocol for control of shunt infections.

METHOD

The shunt infection rate and risk factors for shunt infection were determined for two periods, namely the period 2001-2002 (Patient Material A), and the period 2005-2008 (Patient Material B). The perioperative protocol was introduced in 2005 before the second period.

RESULTS

The total patient material includes 901 patients, in whom 1,404 shunt procedures were performed during the study periods. While the overall infection rate dropped nonsignificantly from 6.5 % to 4.3 %, infection rate dropped markedly and significantly from 18.4 % to 5.7 % among the children younger than 1 year (p = 0.016). The significant risk factors for shunt infection were in Patient Material A age below 1 year (p < .001), and in Patient Material B premature birth (p = 0.045), postoperative cerebrospinal fluid (CSF) leakage (p < .001) and high American Society of Anaesthesiologists (ASA) score (p = 0.039). Of the protocol steps, only the lack of preoperative wash with 4 % clorhexidine gluconate (Hibiscrub®) showed a tendency of influencing the shunt infection rate (p = 0.051).

CONCLUSIONS

This study showed that implementation of a perioperative protocol markedly and significantly reduced shunt infection rate in children younger than 1 year, even though no significant overall reduction in shunt infection rate was found.

Ventriculoperitoneal shunt infection with non-typhoidal Salmonella species in an infant

Shunt infections are common in pediatric neurosurgery. We present a case of a 3-month-old male with a history of a ventriculoperitoneal shunt for posthemorrhagic hydrocephalus after premature birth who presented to the emergency department with irritability and decreased oral intake. His presentation was concerning for shunt infection and evaluation for this was undertaken. He was found to have a shunt infection due to non-Salmonellatyphi species, a rare cause of meningitis in children in the United States and rarer cause of shunt infection. With effective treatment for this organism, the patient did well and was discharged home in good condition.

Predictors of ventricular shunt infection among children presenting to a pediatric emergency department

OBJECTIVES

Among a population of children with a ventricular shunt presenting to a pediatric emergency department (ED), and in whom cerebrospinal fluid (CSF) was obtained, we sought to (1) determine the rate of positive CSF bacterial culture and (2) identify clinical predictors of ventricular shunt infection.

METHODS

We performed a retrospective cohort study of children 3 months to 21 years of age evaluated in a single pediatric tertiary ED from 1995 to 2008. All included children had CSF obtained within 24 hours of presentation to the ED. A shunt infection was defined by growth of bacteria in the CSF of a child who underwent shunt removal within 7 days of presentation.

RESULTS

Nine hundred seventy-nine children met the inclusion criteria; 130 patients (13%) had growth of bacteria in CSF, of which 58 (5.9% of total) had a shunt infection. The median time since last shunt revision or replacement was shorter for patients with a shunt infection compared with children without shunt infection (44 vs 209 days, P = 0.001). After adjustment for patient age, the following factors were associated with shunt infection: shunt revision within the prior 90 days (adjusted odds ratio [aOR], 2.4; 95% CI, 1.3-4.4), presence of fever (aOR, 8.4; 95% CI, 4.3-16.3), and white blood cell count greater than 15,000/μL (aOR, 3.2; 95% CI, 1.5-6.6).

CONCLUSIONS

Among children with a ventricular shunt who had CSF obtained in the ED, the presence of recent shunt revision, fever, and leukocytosis was associated with ventricular shunt infection.

Propionibacterium acnes: infection beyond the skin

Propionibacterium acnes is a Gram-positive bacterium that forms part of the normal flora of the skin, oral cavity, large intestine, the conjunctiva and the external ear canal. Although primarily recognized for its role in acne, P. acnes is an opportunistic pathogen, causing a range of postoperative and device-related infections. These include infections of the bones and joints, mouth, eye and brain. Device-related infections include those of joint prostheses, shunts and prosthetic heart valves. P. acnes may play a role in other conditions, including inflammation of the prostate leading to cancer, SAPHO (synovitis, acne, pustulosis, hyperostosis, osteitis) syndrome, sarcoidosis and sciatica. If an active role in these conditions is established there are major implications for diagnosis, treatment and protection. Genome sequencing of the organism has provided an insight into the pathogenic potential and virulence of P. acnes.

Activity of an antimicrobial hydrocephalus shunt catheter against Propionibacterium acnes

Shunt infection is a major complication affecting approximately 10% of procedures. Propionibacterium acnes, an anaerobic skin bacterium, is increasingly recognized as a shunt pathogen, causing up to 14% of infections. Though susceptible to penicillin and cephalosporins, P. acnes shunt infections are not preventable by means of perioperative prophylaxis, due to poor cerebrospinal fluid penetration. Antimicrobial shunts with activity against staphylococci are available, but their activity against P. acnes is unknown, and the study was designed to determine this. Three methods of evaluation were used in order to determine the emergence of resistance when exposure is to high inocula for long periods, the time taken to kill 100% of the bacteria attached to the shunt, and the duration of activity under constant flow conditions with repeated bacterial challenge. Despite repeated exposure to high bacterial inocula over 70 days, no resistance was seen. The time taken to kill all attached bacteria, 96 h, was twice that taken to kill attached staphylococci. Nevertheless, under constant flow conditions with repeated challenges, the antimicrobial catheters resisted colonization by P. acnes for 56 days. Using tests that were designed to be clinically predictive when done together, the results suggest that the antimicrobial catheters will be able to prevent colonization of hydrocephalus shunts by P. acnes.

Abdominal cerebrospinal fluid (CSF) pseudocyst presented with inferior vena caval obstruction and hydronephrosis

PURPOSE

Abdominal cerebrospinal fluid (CSF) pseudocyst is an uncommon complication of ventriculo-peritoneal shunt placement. A large pseudocyst may exert a significant pressure effect, but vascular or urological symptoms are extremely rare. We report an unusual case of a CSF pseudocyst causing inferior vena caval and ureteric obstruction.

CASE

A 14-year-old girl had previously undergone ventriculo-peritoneal shunting for congenital hydrocephalus. She developed bilateral ankle edema as the only presenting symptom of a large non-infected cerebrospinal CSF pseudocyst. The associated abdominal distension was initially attributed to obesity, and the patient was unable to communicate due to developmental delay. Imaging studies showed that the pseudocyst was causing inferior vena caval obstruction and bilateral hydronephrosis. The ankle edema and hydronephrosis resolved after aspiration of the pseudocyst and shunt revision.

CONCLUSION

Children who require CSF shunting may suffer from associated developmental delay and are frequently unable to communicate their symptomatic complaints. This case illustrated the importance of a heightened clinical suspicion in managing these patients in whom shunt failure may present with subtle and obscure signs of lower body venous congestion.

Massive ascites as unique sign of shunt infection by Propionibacterium acnes

Propionibacterium acnes (P. acnes) has been associated with shunt infection. The signs of infection are mild. We report on a case of P. acnes shunt infection presenting with massive ascites as the unique sign of CSF infection. Shunt removal, antibiotic therapy and drenaige of ascites were performed with a rapid clinical recovery.