Nosocomial meningitis in intensive care: a 10-year retrospective study and literature review

A retrospective analysis of 20,178 adult neurological infection admissions to United Kingdom critical care units from 2001 to 2020

BACKGROUND

Neurological infection is an important cause of critical illness, yet little is known on the epidemiology of neurological infections requiring critical care.

METHODS

We analysed data on all adults with proven or probable neurological infection admitted to UK (NHS) critical care units between 2001 and 2020 reported to the Intensive Care National Audit and Research Centre. Diagnoses, physiological variables, organ support and clinical outcomes were analysed over the whole period, and for consecutive 5-year intervals within it. Predictors of in-hospital mortality were identified using a backward stepwise regression model.

RESULTS

We identified 20,178 critical care admissions for neurological infection. Encephalitis was the most frequent presentation to critical care, comprising 6725 (33.3%) of 20,178 cases. Meningitis- bacterial, viral or unspecified cases - accounted for 10,056 (49.8%) of cases. In-hospital mortality was high, at 3945/19,765 (20.0%) overall. Over the four consecutive 5-year periods, there were trends towards higher Glasgow Coma Scale scores on admission, longer critical care admissions (from median 4 [IQR 2-8] to 5 days [IQR 2-10]), and reduced in-hospital mortality (from 24.9 to 18.1%). We identified 12 independent predictors of in-hospital death which when used together showed good discrimination between patients who die and those who survive (AUC = 0.79).

CONCLUSIONS

Admissions with neurological infection to UK critical care services are increasing and the mortality, although improving, remains high. To further improve outcomes from severe neurological infection, novel approaches to the evaluation of risk stratification, monitoring and management strategies are required.

Clinical Characteristics, Treatment, and Outcomes of Veterans with Cerebrospinal Fluid Culture Positive for Gram-Negative Rod Bacteria: A Retrospective Analysis over 18 Years in 125 Veterans Health Administration Hospitals

Optimal management for patients with bacterial ventriculitis/meningitis due to Gram-negative rods (GNRs) has yet to be well investigated. We assessed the clinical characteristics, treatment, and outcomes of patients with a positive cerebrospinal fluid (CSF) culture for GNRs. We conducted a retrospective cohort study of all patients with a positive CSF culture within the Veterans Health Administration (VHA) system during 2003-2020. Clinical and microbiological characteristics between the true meningitis and contamination groups were compared. Of the 5919 patients with positive CSF cultures among 125 nationwide VHA acute-care hospitals, 297 (5.0%) were positive for GNRs. Among 262 patients analyzed, 156 (59.5%) were assessed as patients with true meningitis, and 106 (40.5%) were assessed as patients with contaminated CSF cultures. Patients with true meningitis had a significantly higher CSF protein (median 168 vs 57 mg/dL, p < 0.001), CSF white blood cell count (median 525 vs 3/µL, p = 0.008) and percentage of neutrophils in CSF (median 88 vs 4%, p < 0.001). Enterobacterales were more common in the true meningitis group, while unidentified GNR or polymicrobial CSF cultures were more common in the contamination group. The all-cause 90-day mortality was 25.0% (39/156) in patients with true meningitis and 10.4% (11/106) in those with contaminated CSF cultures. None of the 11 patients with contaminated CSF cultures who died were considered due to missed meningitis. More than 40% of patients with a positive CSF culture with GNR did not receive treatment without negative consequences. Careful clinical judgment is required to decide whether to treat such patients.

Neurosurgical management of penetrating brain injury during World War I: A historical cohort

During World War I, 25% of penetrating injuries were in the cephalic region. Major Henri Brodier described his surgical techniques in a book in which he reported every consecutive penetrating brain injury (PBI) that he operated on from August 1914 to July 1916. The aim was to collate his data and discuss significant differences in management between soldiers who survived and those who died. We conducted a retrospective survey that included every consecutive PBI patient operated on by Henri Brodier from August 1914 to April 1916 and recorded in his book. We reported medical and surgical management. Seventy-seven patients underwent trepanation by Henri Brodier for PBI. Regarding injury mechanism, 66 procedures (86%) were for shrapnel injury. Regarding location, 21 (30%) involved the whole convexity. Intracranial venous sinus wound was diagnosed intraoperatively in 11 patients (14%). Postoperatively, 7 patients (9%) had seizures, 5 (6%) had cerebral herniation, 3 (4%) had cerebral abscess, and 5 (6%) had meningitis. No patients with abscess or meningitis survived. No significant intergroup differences were found for injury mechanism or wound location, including the venous sinus. Extensive initial surgery with debridement must be prioritized. Infectious complications must not be neglected. We should not forget the lessons of the past when managing casualties in present-day and future conflicts.

Bacterial meningitis in adults: a retrospective study among 148 patients in an 8-year period in a university hospital, Finland

BACKGROUND

Bacterial meningitis (BM) causes significant morbidity and mortality. We investigated predisposing factors, clinical characteristics, spectrum of etiological bacteria, and clinical outcome of community-acquired and nosocomial BM.

METHODS

In this retrospective study we analyzed data of 148 adults (age > 16 years) with BM treated in Turku University Hospital, Southwestern Finland, from 2011 to 2018. Besides culture- or polymerase chain reaction (PCR)-positive cases we also included culture-negative cases with laboratory parameters strongly suggestive of BM and those with meningitis-related findings in imaging. We used Glasgow Outcome Scale (GOS) score 1-4 to determine unfavorable outcome.

RESULTS

The median age of patients was 57 years and 48.6% were male. Cerebrospinal fluid (CSF) culture for bacteria showed positivity in 50 (33.8%) cases, although pre-diagnostic antibiotic use was frequent (85, 57.4%). The most common pathogens in CSF culture were Streptococcus pneumoniae (11, 7.4%), Staphylococcus epidermidis (7, 4.7%), Staphylococcus aureus (6, 4.1%) and Neisseria meningitidis (6, 4.1%). Thirty-nine patients (26.4%) presented with the triad of fever, headache, and neck stiffness. A neurosurgical procedure or an acute cerebral incident prior BM was recorded in 74 patients (50%). Most of the patients had nosocomial BM (82, 55.4%) and the rest (66, 44.6%) community-acquired BM. Ceftriaxone and vancomycin were the most used antibiotics. Causative pathogens had resistances against the following antibiotics: cefuroxime with a frequency of 6.8%, ampicillin (6.1%), and tetracycline (6.1%). The case fatality rate was 8.8% and the additional likelihood of unfavorable outcome 40.5%. Headache, decreased general condition, head computed tomography (CT) and magnetic resonance imaging (MRI), hypertension, altered mental status, confusion, operative treatment, neurological symptoms, pre-diagnostic antibiotic use and oral antibiotics on discharge were associated with unfavorable outcome.

CONCLUSIONS

The number of cases with nosocomial BM was surprisingly high and should be further investigated. The usage of pre-diagnostic antibiotics was also quite high. Headache was associated with unfavorable outcome. The frequency of unfavorable outcome of BM was 40.5%, although mortality in our patients was lower than in most previous studies.

Bacterial meningitis in children with an abnormal craniocerebral structure

Background

We studied the causative pathogens, clinical characteristics, and outcome of bacterial meningitis in children with an abnormal craniocerebral structure.

Methods

A retrospective single-center study was conducted on children aged in the range of 29 days to 14 years by using data obtained from the pediatric intensive care unit in Shengjing Hospital between January 2014 and August 2021. All children were diagnosed with bacterial meningitis. They were divided into complex and simple groups by taking into account the presence of an abnormal craniocerebral structure before they contracted bacterial meningitis. We collected data on demographics, clinical presentations, laboratory results, imaging studies, treatments, and outcomes.

Results

A total of 207 patients were included in the study (46 in the complex group and 161 in the simple group). Patients in the complex group had a lower mortality rate (6.5% vs. 11.2%, p < 0.05), positive blood culture (13.0% vs. 34.8%; p < 0.05), multiple organ dysfunction syndrome (0% vs. 9.3%; p < 0.05), and shock (2.2% vs. 9.3%; p = 0.11). These patients were more often detected with neurological sequelae (80.4% vs. 53.4%; p < 0.05), cerebrospinal fluid drainage (50% vs. 15.5%; p < 0.05), nosocomial infection (54.3% vs. 3.1%; p < 0.05), and multidrug-resistant bacteria (62.5% vs. 55.6%, p = 0.501). In patients in the simple group, infection was mostly confined to the nervous system.

Conclusion

Bacterial meningitis patients with an abnormal craniocerebral structure had fewer bloodstream infections, lower mortality rates, and higher incidence rates of neurological sequelae. Pathogens were more likely to be nosocomial and multidrug-resistant bacteria.

Healthcare-associated central nervous system infections

PURPOSE OF REVIEW

The aim of this review is to provide a practical and updated summary on healthcare-associated central nervous system infections and their management.

RECENT FINDINGS

The term 'healthcare-associated ventriculitis and meningitis' has recently been coined and clinical practical guidelines have been published on the management of these nosocomial infections. Many aspects have still to be further investigated (e.g. cerebrospinal fluid biomarkers, indications for novel antibiotics, intrathecal antimicrobial regimens).

SUMMARY

Clinicians should maintain a high index of suspicion for healthcare-associated central nervous system infections in patients with specific risk factors (i.e. recent neurosurgery, cerebrospinal shunts, drains or implantable devices, head/spinal traumatic events), taking into account systemic signs, and alterations in microbiological, imaging, cerebrospinal fluid findings. The diagnosis is often difficult to confirm because of reduced levels of consciousness or coma. Both Gram-positive and Gram-negative (often multidrug-resistant or even pandrug-resistant) microorganisms may be the cause. Selection of antibiotics must consider susceptibility and penetration into the central nervous system. Ineffective treatments are frequent, and mortality can reach 60%. Future research should focus on the diagnostic performance of biomarkers and on the use of novel antimicrobial regimens, especially for the treatment of difficult to treat infections.

Etiology and Outcomes of Healthcare-Associated Meningitis and Ventriculitis—A Single Center Cohort Study

Healthcare associated meningitis and ventriculitis (HCAMV) are serious complications of neurosurgical procedures. We conducted a retrospective cohort study of patients with HCAMV treated at the University Hospital for Infectious Diseases Zagreb during the 2013–2019 period. A total of 144 patients with 151 episodes of HCAMV were included. The most common indications for neurosurgical procedures were brain tumor, hemorrhage and hydrocephalus. Etiology was identified in 90 (59.6%) episodes (either positive CSF culture or positive PCR), and in other 61 (40.39%) the diagnosis of HCAMV was made based on clinical and CSF parameters, without microbiologic confirmation. Carbapenem-resistant Acinetobacter baumannii was the most common pathogen (15.89%), followed by Staphylococcus aureus (13.91%), Pseudomonas aeruginosa (13.25%) and Coagulase negative staphylococci (7.95%). Overall, 24 (16.3%) patients died, and the majority had adverse outcomes, persistent vegetative state (8, 5.56%) and severe disability (31, 21.53%). The worst clinical outcomes were observed in A. baumannii infections. High rate of complications, the need for external ventricular drainage (re)placement often complicated with nosocomial infections and prolonged stay in intensive care units were observed. Clinicians should be aware of local microbial epidemiology on guiding proper empirical antimicrobial treatment in patients with HCAMV.