Lumbar puncture and brain herniation in acute bacterial meningitis: a review

Comparison of international guidelines for CT prior to lumbar puncture in patients with suspected meningitis

PURPOSE

To compare the performance of multiple international guidelines in selecting patients for head CT prior to lumbar puncture (LP) in suspected meningitis, focusing on identification of potential contraindications to immediate LP.

METHODS

Retrospective study of 196 patients with suspected meningitis presenting to an emergency department between March 2013 and March 2023 and undergoing head CT prior to LP. UK Joint Specialist Society Guidelines (UK), European Society of Clinical Microbiology and Infectious Diseases (ESCMID) and Infectious Diseases Society of America (IDSA) guidelines were evaluated by cross-referencing imaging criteria with clinical characteristics present at time of presentation. Sensitivity of each guideline for recommending neuroimaging in cases with brain shift on CT was evaluated, along with the number of normal studies and incidental or spurious findings.

RESULTS

2/196 (1%) patients had abnormal CTs with evidence of brain shift, while 14/196 (7%) had other abnormalities on CT without brain shift. UK, ESCMID and IDSA guidelines recommended imaging in 10%, 14% and 33% of cases respectively. All three guidelines recommended imaging pre-LP in 2/2 (100%) cases with brain shift. IDSA guidelines recommended more CT studies with normal findings (59 vs 16 and 24 for UK and ESCMID guidelines respectively) and CT abnormalities without brain shift (4 vs 1 and 2 respectively) than the other guidelines.

CONCLUSION

UK, ESCMID and IDSA guidelines are all effective at identifying the small cohort of patients who benefit from a head CT prior to LP. Following the more selective UK/ESCMID guidelines limits the number of normal studies and incidental or spurious CT findings.

Detection and Management of Elevated Intracranial Pressure in the Treatment of Acute Community-Acquired Bacterial Meningitis: A Systematic Review

Acute bacterial meningitis (ABM) is associated with severe morbidity and mortality. The most prevalent pathogens in community-acquired ABM are Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae. Other pathogens may affect specific patient groups, such as newborns, older patients, or immunocompromised patients. It is well established that ABM is associated with elevated intracranial pressure (ICP). However, the role of ICP monitoring and management in the treatment of ABM has been poorly described.An electronic search was performed in four electronic databases: PubMed, Web of Science, Embase, and the Cochrane Library. The search strategy chosen for this review used the following terms: Intracranial Pressure AND (management OR monitoring) AND bacterial meningitis. The search yielded a total of 403 studies, of which 18 were selected for inclusion. Eighteen studies were finally included in this review. Only one study was a randomized controlled trial. All studies employed invasive ICP monitoring techniques, whereas some also relied on assessment of ICP-based on clinical and/or radiological observations. The most commonly used invasive tools were external ventricular drains, which were used both to monitor and treat elevated ICP. Results from the included studies revealed a clear association between elevated ICP and mortality, and possibly improved outcomes when invasive ICP monitoring and management were used. Finally, the review highlights the absence of clear standardized protocols for the monitoring and management of ICP in patients with ABM. This review provides an insight into the role of invasive ICP monitoring and ICP-based management in the treatment of ABM. Despite weak evidence certainty, the present literature points toward enhanced patient outcomes in ABM with the use of treatment strategies aiming to normalize ICP using continuous invasive monitoring and cerebrospinal fluid diversion techniques. Continued research is needed to define when and how to employ these strategies to best improve outcomes in ABM.

Meningeal regulation of infections: A double-edged sword

In the past 10 years, important discoveries have been made in the field of neuroimmunology, especially regarding brain borders. Indeed, meninges are protective envelopes surrounding the CNS and are currently in the spotlight, with multiple studies showing their involvement in brain infection and cognitive disorders. In this review, we describe the meningeal layers and their protective role in the CNS against bacterial, viral, fungal, and parasitic infections, by immune and nonimmune cells. Moreover, we discuss the neurological and cognitive consequences resulting from meningeal infections in neonates (e.g. infection with group B Streptococcus, cytomegalovirus, …) or adults (e.g. infection with Trypanosoma brucei, Streptococcus pneumoniae, …). We hope that this review will bring to light an integrated view of meningeal immune regulations during CNS infections and their neurological consequences.

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.

Hepatitis B virus in cerebrospinal fluid of a patient with purulent bacterial meningitis detected by multiplex-PCR: A case report

BACKGROUND

Bacterial meningitis (BM) is a common central nervous system inflammatory disease. BM may cause serious complications, and early diagnosis is essential to improve the prognosis of affected patients.

CASE SUMMARY

A 37-year-old man was hospitalized with purulent meningitis because of worsening headache for 12 h, accompanied by vomiting, fever, and rhinorrhea. Head computed tomography showed a lesion in the left frontal lobe. Infectious disease screening showed positivity for hepatitis B surface antigen, hepatitis B e antigen, and hepatitis B core antigen. Cerebrospinal fluid (CSF) leak was suspected based on clinical history. Streptococcus pneumoniae (S. pneumoniae) was detected in CSF by metagenomic next-generation sequencing (mNGS) technology, confirming the diagnosis of purulent BM. After treatment, multiplex PCR indicated the presence of hepatitis B virus (HBV) DNA and absence of S. pneumoniae DNA in CSF samples.

CONCLUSION

We report a rare case of HBV in the CSF of a patient with purulent BM. Multiplex PCR is more sensitive than mNGS for detecting HBV DNA.

Lumbar Puncture for Diagnosis of Idiopathic Intracranial Hypertension in Typical Patients

BACKGROUND

Patients with typical features of pseudotumor cerebri syndrome (PTCS) must undergo lumbar puncture (LP) to demonstrate elevated opening pressure and cerebrospinal fluid (CSF) analysis to rule out alternative diagnoses. As LP may be associated with significant morbidity, this study aims to determine its necessity in diagnosing typical PTCS.

METHODS

Retrospective chart review at 3 university-based neuro-ophthalmology practices included women aged 18-45 years with body mass index >25, papilledema, negative neuroimaging, and who met criteria for PTCS or probable PTCS.

RESULTS

One hundred fifty-six patients were enrolled. Seven (4.5%) had clinically insignificant CSF abnormalities. No diagnoses or management changed based on LP/CSF results.

CONCLUSION

LP may not be routinely required in the initial evaluation of typical patients with PTCS evaluated by experienced clinicians We caution, however, that further prospective study is required to determine potential risks and benefits of LP as a tool in the diagnosis of IIH before recommending general practice changes.

Approach to Neurologic Infections

PURPOSE OF REVIEW

This article provides an overview of the clinical approach to the diagnosis of neurologic infections, focusing on the symptoms, signs, imaging features, and laboratory findings of the major categories of neuroinfectious diseases.

RECENT FINDINGS

The increased use of immunosuppressive and immunomodulatory therapy to treat autoimmune diseases has led to an increase in opportunistic neurologic infections. The description of numerous causes of autoimmune antibody-mediated encephalitis over the past decade has expanded the differential diagnosis of encephalitis beyond infection. The emergence of metagenomic next-generation sequencing has led to diagnoses of rare or unexpected causes of neurologic infections and has the potential to enhance diagnostic precision in neuroinfectious diseases.

SUMMARY

Infections of the nervous system can affect any level of the neuraxis and present over any time course. Neurologic infections may present atypically with respect to clinical, radiologic, and CSF analysis features in immunocompromised patients or older adults. A thorough evaluation including systemic features, past medical history, travel, exposures, detailed examination, neuroimaging, and CSF analysis is often necessary to make a definitive diagnosis. It is important to be aware of the test characteristics and limitations of microbiological tests on CSF for neurologic infections to avoid being misled by false positives or false negatives.

Neuroinfectious Disease Emergencies

Neuroinfectious diseases can affect immunocompetent and immunosuppressed individuals and cause a variety of emergencies including meningitis, encephalitis, and abscess. Neurologic infections are frequently complicated by secondary injuries that also present emergently such as cerebrovascular disease, acute obstructive hydrocephalus, and seizure. In most cases, timely recognition and early treatment of infection can improve the morbidity and mortality of infectious neurologic emergencies.

Clinical utility of cerebrospinal fluid vitamin D-binding protein as a novel biomarker for the diagnosis of viral and bacterial CNS infections

Background

Rapid and accurate diagnosis of central nervous system (CNS) infections is important, and laboratory tests help diagnose CNS infections. Even when the patient has symptoms, laboratory tests often do not reveal any specific findings. The potential of vitamin D-binding protein (VDBP) to be used as a biomarker for viral and bacterial CNS infections was studied.

Methods

A total of 302 subjects with suspected CNS infection who underwent lumbar puncture were included. Clinical and laboratory data were collected retrospectively. VDBP levels were measured in the cerebrospinal fluid (CSF) samples. Genotyping for the GC gene encoding VDBP was also performed. VDBP levels were analyzed and compared by CNS infection, pathogen, CSF opening pressure, and GC genotype.

Results

A CNS infection group (n = 90) and a non-CNS infection group (n = 212) were studied. In terms of its receiver operating characteristic, CSF VDBP showed an area under the curve of 0.726 for the diagnosis of CNS infection. CSF VDBP levels were significantly different between the CNS infection and non-infection groups. The CNS infection group with enterovirus showed a statistically lower distribution of CSF VDBP levels than the other virus groups. The group with CSF opening pressure > 25 cmH₂O showed higher CSF VDBP levels than the other groups. There was no significant difference in GC gene allele distribution between the CNS infection and non-infection groups.

Conclusions

CSF VDBP levels were increased in patients with CNS infection. The CSF VDBP showed potential as a new biomarker for viral and bacterial CNS infections.

Lumbar Puncture: Indications, Challenges and Recent Advances

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The value of cerebrospinal fluid ubiquitin C-terminal hydrolase-L1 protein as a prognostic predictor of neurologic outcome in post-cardiac arrest patients treated with targeted temperature management

AIM

We evaluated the prognostic value of serum- and cerebrospinal fluid (CSF)-ubiquitin carboxyl-terminal esterase L1 protein (UCHL1) measurements in post- post-out of hospital cardiac arrest (OHCA) patients treated with target temperature management (TTM), to predict neurologic outcome.

METHODS

This was a prospective single-centre observational cohort study, conducted from April 2018 to September 2019. Serum- and CSF-UCHL1 were obtained immediately (UCHL1_initial), 24 h (UCHL1₂₄), 48 h (UCHL1₄₈), and 72 h (UCHL1₇₂) after return of spontaneous circulation (ROSC). The area under the receiver operating characteristic curves (AUROC) and Delong method were used to identify cut-off values of serum- and CSF-UCHL1_initial, UCHL1₂₄, UCHL1₄₈, UCHL1₇₂ for predicting neurologic outcomes.

RESULTS

Of 38 patients enrolled, 16 comprised the poor outcome group. The AUROCs for serum- and CSF-UCHL1_initial were 0.71 and 0.93 in predicting poor neurological outcomes, respectively (p = 0.01). The AUROCs for serum- and CSF-UCHL1₂₄ were 0.85 and 0.91 (p = 0.24). The AUROCs for serum- and CSF-UCHL1₄₈ were 0.90 and 0.97 (p = 0.07). The AUROCs for serum- and CSF-UCHL1₇₂ were 0.94 and 0.98 (p = 0.25).

CONCLUSION

Findings of this study demonstrate that CSF-UCHL1 measured immediately, 24, 48, and 72 h after ROSC is a valuable predictor for evaluating neurologic outcomes, whereas serum-UCHL1 measured at 24, 48, and 72 h after ROSC showed a significant performance in the prognostication of poor outcomes in post-OHCA patients treated with TTM.

Misinterpretations of Guidelines Leading to Incorrect Diagnosis of Brain Death: A Case Report and Discussion

Guidelines describe the process necessary for the diagnosis of brain death. We present a case of a 3-month-old former 36-week-gestation infant after a prolonged out-of-hospital cardiac arrest of 37 minutes who was clinically diagnosed as brain dead at 120 hours after the event. Unusual findings included a normal slightly sunken anterior fontanelle, normal cerebral blood flow perfusion scan at 73 hours after the event, only localized parieto-temporal edema on the latest computed tomographic (CT) scan of the brain at 48 hours after the event, and discussion of whether nonconvulsive seizures could have confounded the examination for brain death. In light of these unusual findings, we discuss and highlight what may be common misinterpretations of brain death guidelines that led to the mistaken diagnosis of death (as opposed to severe neurologic injury) in this child.

Acute Bacterial Meningitis

PURPOSE OF REVIEW

While acute bacterial meningitis is becoming less common in developed countries because of the widespread use of vaccines against Streptococcus pneumoniae, Neisseria meningitides, and Haemophilus influenzae, bacterial meningitis still occurs worldwide, with peak incidence in young children and the elderly. Bacterial meningitis is usually lethal unless appropriate antibiotics that cross the blood-brain barrier are given. Clinical suspicion of bacterial meningitis begins when patients present with the abrupt onset of fever, headache, and meningismus.

RECENT FINDINGS

New technologies are being developed for more rapid identification of the bacterial species causing meningitis. When appropriate, administration of adjunctive dexamethasone with the antibiotics often lessens neurologic sequelae in survivors, which may include aphasia, ataxia, paresis, hearing loss, and cognitive impairment.

SUMMARY

Confirmation of the diagnosis of bacterial meningitis comes mainly from examination and culture of CSF obtained from a lumbar puncture. Typically, the CSF shows an elevated neutrophil count, elevated protein, depressed glucose, positive Gram stain, and growth of the bacteria on appropriate culture media. Antibiotic sensitivities of the bacteria determine the appropriate antibiotics, although an educated guess of the best antibiotics to be given promptly must be made until the antibiotic sensitivities return, usually in a few days.

Think central nervous system tuberculosis, also in low-risk children: a Danish nationwide survey

BACKGROUND

Paediatric central nervous system (CNS) tuberculosis (TB) imposes a high risk of death and neurologic sequelae, particularly if the diagnosis is delayed. Children from non-TB endemic countries are particularly at risk of delayed or missed diagnosis. We aimed to investigate CNS TB in Denmark, a TB low-endemic country and where Bacillus Calmette-Guerin (BCG) vaccination is not a part of the vaccination schedule.

METHODS

A nationwide retrospective case survey of all children with CNS TB in 2000-2015 identified through the National Danish TB Notification Register. We assessed epidemiology, clinical and paraclinical features, diagnostic criteria, treatment and outcome.

RESULTS

Nine ethnic Danes and 12 children from TB-endemic countries with CNS TB were identified. Clinical features, C-reactive protein, chest X-ray and indirect TB screening assays all had low sensitivity (19-75%). All (18/18) patients had elevated cerebrospinal fluid (CSF) white blood cells and 15 of 17 (88%) had a combination of at least two characteristic CSF findings (lymphocyte predominance, elevated protein and/or hypoglycorrhachia). Cerebral computed tomography and magnetic resonance imaging were abnormal in 10 of 16 (63%) and 12 of 14 (86%), respectively. Treatment was initiated after a median of 3 days in children from TB-endemic countries, and after 10 days in ethnic Danish children. One patient died (5%): A native Danish girl who died before the diagnosis was established.

CONCLUSIONS

Children from non-TB endemic countries may be at risk of delayed diagnosis and poorer prognosis compared to high-risk children. Cerebral magnetic resonance imaging and characteristic CSF findings had high diagnostic sensitivity.

Epidemiology of lumbar punctures in hospitalized patients in the United States

Objectives

Lumbar puncture (LP) is an important technique for assessing and treating neurological symptoms. The objective of this study was to describe the characteristics of diagnostic lumbar punctures performed on hospitalized patients in the United States.

Methods

We analyzed data from the 2010 National Inpatient Sample (NIS) and the National Emergency Department Survey (NEDS). We included patients treated in the Emergency Department (ED) as well as those admitted to an inpatient bed through the ED. We identified patients undergoing LPs from ICD-9 procedural code 03.31 and CPT code 62270. We generated nationally weighted estimates of the total number of LPs. We also assessed patient and hospital characteristics of cases undergoing LP.

Results

Of an estimated 135 million hospitalizations (ED + admission, or ED only), there were an estimated 362,718 LPs (331,248–394,188), including 273,612 (251,850–295,375) among adults and 89,106 (71,870–106,342) among children (<18 years old). Of the 362,718 LPs, 136,764 (122,117–151,410) were performed in the ED without admission. The most common conditions associated with LP among children were fever of unknown origin, meningitis, seizures and other perinatal conditions. The most common conditions associated with LP among adults were headache and meningitis.

Conclusions

Lumbar Puncture remains an important procedure for diagnostic and therapeutic uses in United States Hospitals.

Anesthetic management of parturients with Arnold Chiari malformation-I: a multicenter retrospective study

BACKGROUND

Consensus regarding the safest mode of delivery and anesthetic management for parturients with Arnold Chiari malformation-I (ACM-I) remains controversial. This study assessed their anesthetic management and reported anesthetic complications during hospitalization for delivery.

METHODS

This was a multicenter, retrospective, cohort study of patients with ACM-I undergoing vaginal or cesarean delivery. Data were obtained from the electronic databases of four United States academic institutions using International Classification of Diseases (ICD) codes from 2007-2017 at three sites and 2004-2017 at one site. The primary outcome was anesthetic complications.

RESULTS

Data were analyzed for 185 deliveries in 148 patients. Diagnosis of ACM-I was made prior to delivery in 147 (80%) cases. Pre-delivery neurosurgical consultation for management of ACM-I was performed in 53 (36%) patients. Pre-existing symptoms were recorded for 89 (48%) of the deliveries. Vaginal deliveries occurred in 80 (43%) cases, and 62 women (78%) received neuraxial labor analgesia. Cesarean delivery was performed in 105 (57%) cases, of which 70 women (67%) had neuraxial anesthesia and 34 (32%) received general anesthesia. Post-dural puncture headache was reported in three (2%) patients who had neuraxial anesthesia, and in two (12%) patients with syringomyelia. There was one (3%) reported case of aspiration pneumonia with general anesthesia.

CONCLUSIONS

The findings suggest that anesthetic complications occur infrequently in patients with ACM-I regardless of the anesthetic management. Although institutional preference in anesthetic and obstetric care appears to drive patient management, the findings suggest that an individualized approach has favorable outcomes in this population.

Where there is no brain imaging: Safety and diagnostic value of lumbar puncture in patients with neurological disorders in a rural hospital of Central Africa

Analysis of cerebrospinal fluid (CSF) obtained by lumbar puncture (LP) is an essential step for the diagnostic approach of neurological disorders, in particular neuro-infections. In low-resource settings, it is even often the only available diagnostic method. Despite its key contribution, little is known on the risks and benefits of LP in the large tropical areas where hospital-based neuroimaging is not available. The objectives of this study were to assess the safety and diagnostic yield of LP in a rural hospital of central Africa and to identify predictors of CSF pleocytosis (white blood cell count >5/μL) as surrogate marker of neuro-infections. From 2012 to 2015, 351 patients admitted for neurological disorders in the rural hospital of Mosango, Kwilu province, Democratic Republic of Congo, were evaluated using a systematic clinical and laboratory workup and a standard operating procedure for LP. An LP was successfully performed in 307 patients (87.5%). Serious post-LP adverse events (headache, backache or transient confusion) were observed in 23 (7.5%) of them but were self-limiting, and no death or long-term sequelae were attributable to LP. CSF pleocytosis was present in 54 participants (17.6%), almost always associated with neuro-infections. Presenting features strongly and independently associated with CSF pleocytosis were fever, altered consciousness, HIV infection and positive screening serology for human African trypanosomiasis. In conclusion, the established procedure for LP was safe in this hospital setting with no neuroimaging and CSF analysis brought a substantial diagnostic contribution. A set of presenting features may help accurately selecting the patients for whom LP would be most beneficial.

Pitfalls in the diagnosis of meningitis in neonates and young infants: the role of lumbar puncture

Meningitis occurs frequently in neonates and can lead to a number of acute, severe complications and long-term disabilities. An early diagnosis of neonatal meningitis is essential to reduce mortality and to improve outcomes. Initial clinical signs of meningitis are often subtle and frequently overlap with those of sepsis, and current haematologic tests do not distinguish sepsis from meningitis. Thus, lumbar puncture (LP) remains the gold standard for the diagnosis of meningitis in infants, and this procedure is recommended in clinical guidelines. Nevertheless, in clinical practice, LP is frequently deferred or omitted due to concerns regarding hypothetical adverse events or limited experience of the performer. Future studies should assess whether a combination of clinical findings and select haematologic tests at disease onset can identify those neonates with the highest risk of meningitis who should undergo LP. Furthermore, clinicians should be convinced that the actual benefits of an early diagnosis of meningitis far outweigh the hypothetical risks associated with LP.

Computed tomography head scans prior to lumbar punctures in suspected meningitis

BACKGROUND

The literature suggests that certain clinical criteria to determine raised intracranial pressure (ICP) should be met if a patient suspected of meningitis is to undergo a computed tomography (CT) head scan prior to having a lumbar puncture (LP).

AIM

To evaluate whether these criteria were being used by the general medicine department of Auckland City Hospital when requesting CT scans prior to LPs in patients with suspected meningitis.

METHODS

A total of 37 patients admitted under general medicine with suspected meningitis from 1 January to 31 July 2016 were retrospectively audited based on the clinical evidence justifying the decision to do a CT scan prior to a LP.

RESULTS

Only 7 of 24 patients who underwent CT scans had met clinical criteria for raised ICP. There were no abnormalities found on any of the CT scans and approximately two-thirds of these patients had a final diagnosis of viral illness or headache.

CONCLUSION

A large number of patients with suspected meningitis under general medicine at Auckland City Hospital are having CT scans without clinical evidence suggestive of raised ICP.

Using external lumbar CSF drainage to treat communicating external hydrocephalus in adult patients after acute traumatic or non-traumatic brain injury

BACKGROUND

Despite various treatments to control intracranial pressure (ICP) after brain injury, patients may present a late onset of high ICP or a poor response to medications. External lumbar drainage (ELD) can be considered a therapeutic option if high ICP is due to communicating external hydrocephalus. We aimed at describing the efficacy and safety of ELD used in a cohort of traumatic or non-traumatic brain-injured patients.

METHODS

In this multicentre retrospective analysis, patients had a delayed onset of high ICP after the initial injury and/or a poor response to ICP treatments. ELD was considered in the presence of radiological signs of communicating external hydrocephalus. Changes in ICP values and side effects following the ELD procedure were reported.

RESULTS

Thirty-three patients with a median age of 51 years (25-75th percentile: 34-61 years) were admitted after traumatic (n = 22) or non-traumatic (n = 11) brain injuries. Their initial Glasgow Coma Scale score was 8 (4-11). Eight patients underwent external ventricular drainage prior to ELD. Median time to ELD insertion was 5 days (4-8) after brain insult. In all patients, ELD was dramatically effective in lowering ICP: 25 mmHg (20-31) before versus 7 mmHg (3-10) after (p < 0.001). None of the patients showed adverse effects such as pupil changes or intracranial bleeding after the procedure. One patient developed an ELD-related infection.

CONCLUSIONS

These findings indicate that ELD may be considered potentially effective in controlling ICP, remaining safe if a firm diagnosis of communicating external hydrocephalus has been made.

Emergency Medicine Myths: Computed Tomography of the Head Prior to Lumbar Puncture in Adults with Suspected Bacterial Meningitis - Due Diligence or Antiquated Practice?

BACKGROUND

Various sources purport an association between lumbar puncture and brainstem herniation in patients with intracranial mass effect lesions. Several organizations and texts recommend head computed tomography (CT) prior to lumbar puncture in selected patients.

OBJECTIVE

To review the evidence regarding the utility of obtaining head CT prior to lumbar puncture in adults with suspected bacterial meningitis.

DISCUSSION

Observational studies report a risk of post-lumbar puncture brainstem herniation in the presence of intracranial mass effect (1.5%) that is significantly lower than that reported among all patients with bacterial meningitis (up to 13.3%). It is unclear from existing literature whether identifying patients with intracranial mass effect decreases herniation risk. Up to 80% of patients with bacterial meningitis experiencing herniation have no CT abnormalities, and approximately half of patients with intracranial mass effect not undergoing lumbar puncture herniate. Decision rules to selectively perform CT on only those individuals most likely to have intracranial mass effect lesions have not undergone validation. Despite recommendations for immediate antimicrobial therapy prior to imaging, data indicate an association between pre-lumbar puncture CT and antibiotic delays. Recent data demonstrate shortened door-to-antibiotic times and lower mortality from bacterial meningitis after implementation of new national guidelines, which restricted generally accepted CT indications by removing impaired mental status as imaging criterion.

CONCLUSIONS

Data supporting routine head CT prior to lumbar puncture are limited. Physicians should consider selective CT for those patients at risk for intracranial mass effect lesions based on decision rules or clinical gestalt. Patients undergoing head CT must receive immediate antibiotic therapy.

Acute Ataxia in Children: A Review of the Differential Diagnosis and Evaluation in the Emergency Department

Acute ataxia in a pediatric patient poses a diagnostic dilemma for any physician. While the most common etiologies are benign, occasional individuals require urgent intervention. Children with stroke, toxic ingestion, infection, and neuro-inflammatory disorders frequently exhibit ataxia as an essential-if not the only-presenting feature. The available retrospective research utilize inconsistent definitions of acute ataxia, precluding the ability to pool data from these studies. No prospective data exist that report on patients presenting to the emergency department with ataxia. This review examines the reported causes of ataxia and attempts to group them into distinct categories: post-infectious and inflammatory central and peripheral phenomena, toxic ingestion, neurovascular, infectious and miscellaneous. From there, we synthesize the existing literature to understand which aspects of the history, physical exam, and ancillary testing might aid in narrowing the differential diagnosis. MRI is superior to CT in detecting inflammatory or vascular insults in the posterior fossa, though CT may be necessary in emergent situations. Lumbar puncture may be deferred until after admission in most instances, with suspicion for meningitis being the major exception. There is insufficient evidence to guide laboratory evaluation of serum, testing should be ordered based on clinical judgement-recommended studies include metabolic profiles and screening labs for metabolic disorders (lactate and ammonia). All patients should be reflexively screened for toxic ingestions.

Safety of lumbar puncture in comatose children with clinical features of cerebral malaria

Objective:

We assessed the independent association of lumbar puncture (LP) and death in Malawian children admitted to the hospital with the clinical features of cerebral malaria (CM).

Methods:

This was a retrospective cohort study in Malawian children with clinical features of CM. Allocation to LP was nonrandom and was associated with severity of illness. Propensity score–based analyses were used to adjust for this bias and assess the independent association between LP and mortality.

Results:

Data were available for 1,075 children: 866 (80.6%) underwent LP and 209 (19.4%) did not. Unadjusted mortality rates were lower in children who underwent LP (15.3% vs 26.7% in the no-LP group) but differences in covariates between the 2 groups suggested bias in LP allocation. After propensity score matching, all covariates were balanced. Propensity score–based analyses showed no change in mortality rate associated with LP: by inverse probability weighting, the average risk reduction was 2.0% at 12 hours (95% confidence interval −1.5% to 5.5%, p = 0.27) and 1.7% during hospital admission (95% confidence interval −4.5% to 7.9%, p = 0.60). Undergoing LP did not change the risk of mortality in subanalyses of children with severe brain swelling on MRI or in those with papilledema.

Conclusion:

In comatose children with suspected CM who were clinically stable, we found no evidence that LP increases mortality, even in children with objective signs of raised intracranial pressure.

Challenges of bacterial meningitis case management in low income settings: an experience from Ethiopia

OBJECTIVE

To investigate the current diagnostic and therapeutic strategies used in the care of patients with suspected bacterial meningitis at teaching hospitals in Ethiopia.

METHODS

This was a hospital-based retrospective study conducted at four teaching hospitals in different regions of Ethiopia. Participants were patients aged 14 years and older treated for suspected bacterial meningitis. Presenting complaints, diagnostic strategies used and treatments given were obtained from clinical records.

RESULT

A total of 425 patients were included in the study; 52.7% were men and 83.8% were younger than 50 years. Fever, headache, neck stiffness and impaired consciousness were the most common clinical presentations; 55.5% underwent lumbar puncture. Overall, only 96 (22.6%) patients had cerebrospinal fluid abnormalities compatible with bacterial meningitis. A causative bacterium was identified in only 14 cases. Ceftriaxone was used as the empiric treatment of choice, either alone or in combination with other antibiotics; 17.6% of patients were also given vancomycin. Adjunctive dexamethasone was given to 50.4%.

CONCLUSION

Most patients treated as bacterial meningitis did not receive a proper diagnostic workup. The choice of antibiotic was not tailored to the specific clinical condition of the patient. Such an approach may result in poor treatment outcomes and lead to antibiotic resistance. Management of patients with suspected bacterial meningitis should be supported by analysis of cerebrospinal fluid, and treatment should be tailored to local evidence and current evidence-based recommendations.

Clinical decision rules for acute bacterial meningitis: current insights

Acute community-acquired bacterial meningitis (BM) requires rapid diagnosis so that suitable treatment can be instituted within 60 minutes of admitting the patient. The cornerstone of diagnostic examination is lumbar puncture, which enables microbiological analysis and determination of the cerebrospinal fluid (CSF) cytochemical characteristics. However, microbiological testing is not sufficiently sensitive to rule out this diagnosis. With regard to the analysis of standard CSF cytochemical characteristics (polymorphonuclear count, CSF glucose and protein concentration, and CSF:serum glucose), this is often misleading. Indeed, the relatively imprecise nature of the cutoff values for these BM diagnosis markers can make their interpretation difficult. However, there are two markers that appear to be more efficient than the standard ones: CSF lactate and serum procalcitonin levels. Scores and predictive models are also available; however, they only define a clinical probability, and in addition, their use calls for prior validation on the population in which they are used. In this article, we review current methods of BM diagnosis.

The UK joint specialist societies guideline on the diagnosis and management of acute meningitis and meningococcal sepsis in immunocompetent adults

Bacterial meningitis and meningococcal sepsis are rare conditions with high case fatality rates. Early recognition and prompt treatment saves lives. In 1999 the British Infection Society produced a consensus statement for the management of immunocompetent adults with meningitis and meningococcal sepsis. Since 1999 there have been many changes. We therefore set out to produce revised guidelines which provide a standardised evidence-based approach to the management of acute community acquired meningitis and meningococcal sepsis in adults. A working party consisting of infectious diseases physicians, neurologists, acute physicians, intensivists, microbiologists, public health experts and patient group representatives was formed. Key questions were identified and the literature reviewed. All recommendations were graded and agreed upon by the working party. The guidelines, which for the first time include viral meningitis, are written in accordance with the AGREE 2 tool and recommendations graded according to the GRADE system. Main changes from the original statement include the indications for pre-hospital antibiotics, timing of the lumbar puncture and the indications for neuroimaging. The list of investigations has been updated and more emphasis is placed on molecular diagnosis. Approaches to both antibiotic and steroid therapy have been revised. Several recommendations have been given regarding the follow-up of patients.

How to use… lumbar puncture in children

Lumbar puncture (LP) is a useful diagnostic tool in a wide spectrum of paediatric clinical situations. A common indication is to rule out a serious intracranial infection in a febrile child. Success rate can be optimised by proper positioning, appropriate technique and enhanced operator's skill in performing the procedure. The purpose of this review is to explore the indications and contraindications for performing paediatric LP, to describe the anatomical and physiological knowledge required to maximise success rates and to describe complications and their management. We will also provide advice on requesting various cerebrospinal fluid studies, interpretation of results and clinical situations in which LP may be indicated.

Managing acute central nervous system infections in the UK adult intensive care unit in the wake of UK encephalitis guidelines

The acute central nervous system infections meningitis and encephalitis commonly require management on intensive care units. The clinical features often overlap and in the acute phase-altered consciousness and seizures may also need to be managed. In April 2012, the first UK national guideline for the management of suspected viral encephalitis was published by the British Infection Association and Association of British Neurologists, and other key stakeholders, and included a simple management algorithm. The new guideline results from evidence demonstrating a number of common oversights in the standard management of suspected viral encephalitis in many settings. In combination with British Infection Association meningitis guidelines, evidence-based approaches now exist to facilitate the non-expert managing patients with suspected central nervous system infections. Here we bring together these guidelines and the supporting evidence applicable for intensivists into a single resource.

Adult bacterial meningitis: earlier treatment and improved outcome following guideline revision promoting prompt lumbar puncture

BACKGROUND

In suspected acute bacterial meningitis (ABM), cerebral computerized tomography (CT) is recommended before lumbar puncture (LP) if mental impairment. Despite guideline emphasis on early treatment, performing CT prior to LP implies a risk of delayed treatment and unfavorable outcome. Therefore, Swedish guidelines were revised in 2009, deleting impaired mental status as a contraindication for LP without prior CT scan. The aim of the present study was to evaluate the guideline revision.

METHODS

The Swedish quality registry for community-acquired ABM was analyzed retrospectively. Door-to-antibiotic time and outcome were compared among patients treated 2005-2009 (n=394) and 2010-2012 (n=318). The effect of different LP-CT sequences was analyzed during 2008-2012.

RESULTS

Adequate treatment was started 1.2 hours earlier, and significantly more patients were treated <2 hours from admission 2010-2012 than 2005-2009. Compared with CT before LP, immediate LP resulted in 1.6 hours earlier treatment, significant increase in door-to-antibiotic times of <1 and <2 hours, and a favorable outcome. In 2010-2012, mortality was lower (6.9% vs 11.7%) and the risk of sequelae at follow-up decreased (38% vs 49%) in comparison with 2005-2009. Treatment delay resulted in a significantly increased risk for fatal outcome, with a relative increase in mortality of 12.6% per hour of delay.

CONCLUSIONS

The deletion of impaired mental status as contraindication for prompt LP and LP without prior CT scan are associated with significantly earlier treatment and a favorable outcome. A revision of current international guidelines should be considered.

Management of Cryptococcus gattii meningoencephalitis

Cryptococcosis is a fungal disease caused by Cryptococcus neoformans and Cryptococcus gattii. By inhalation and subsequent pulmonary infection, it may disseminate to the CNS and cause meningitis or meningoencephalitis. Most cases occur in immunosuppressed hosts, including patients with HIV/AIDS, patients receiving immunosuppressing drugs, and solid organ transplant recipients. However, cryptococcosis also occurs in individuals with apparently healthy immune systems. A growing number of cases are caused by C gattii, with infections occurring in both immunosuppressed and immunocompetent individuals. In the majority of documented cases, treatment of C gattii infection of the CNS requires aggressive management of raised intracranial pressure along with standard antifungal therapy. Early cerebrospinal fluid evacuation is often needed through placement of a percutaneous lumbar drain or ventriculostomy. Furthermore, pharmacological immunosuppression with a high dose of dexamethasone is sometimes needed to ameliorate a persistently increased inflammatory response and to reduce intracranial pressure. In this Grand Round, we present the case of an otherwise healthy adolescent female patient, who, despite aggressive management, succumbed to C gattii meningoencephalitis. We also present a review of the existing literature and discuss optimum clinical management of meningoencephalitis caused by C gattii.

Techniques that decrease or eliminate ionizing radiation for evaluation of ventricular shunts in children with hydrocephalus

Shunted hydrocephalus in children is a commonly seen diagnosis in hospitals throughout the world and is one of the most common chronic pediatric neurosurgical conditions. These children undergo numerous studies for routine surveillance as well as for evaluation of shunt malfunction, many of which are associated with significant radiation exposure over the child׳s lifetime. It is in the child׳s best interest to minimize the overall exposure to ionizing radiation so as to decrease the chance of the deleterious effects from occurring. The article outlines the epidemiology of ventricular shunt catheters, the typical indications and methods for shunt evaluation, and the preferred alternative imaging methods that eliminate or reduce radiation exposure.

Fulminant bacterial meningitis

BACKGROUND

Fulminant bacterial meningitis is a rare host reaction to infection characterized by sudden onset, rapid deterioration, abrupt cerebral edema and refractory intracranial hypertension associated with an extremely high mortality rate.

METHODS

A search of all relevant medical literature since 1900 was conducted to clarify the nature of this entity and its medical management.

RESULTS

Fulminant meningitis occurs in a small percentage of all cases of bacterial meningitis, at all ages and with all infecting organisms. The mortality rate exceeds 50%. Descriptions of fulminant bacterial meningitis are found in medical literature from the preantibiotic era. Its incidence and clinical character have not changed since the introduction of antibiotics and advanced intensive care medicine. The explosive cerebral edema cannot be predicted, and the underlying molecular pathophysiology remains poorly understood. Vigorous neuroresuscitation and the use of adjunctive techniques to control the cerebral edema have not been shown to modify the extreme intracranial hypertension and risk of herniation.

CONCLUSION

Fulminant bacterial meningitis is an example of an aberrant host response to infection that challenges available medical intervention.

Advanced ultrasound procedures

Ultrasound guidance has become the standard of care for many bedside procedures, owing to its portability, ease of use, and significant reduction in complications. This article serves as an introduction to the use of ultrasonography in several advanced procedures, including pericardiocentesis, thoracentesis, paracentesis, lumbar puncture, regional anesthesia, and peritonsillar abscess drainage.

Fever and neurologic conditions

Neurologic conditions are categorized as either those that cause a change in mental status or those that create a focal finding on physical examination. Neurologic abnormality associated with fever can be caused by a primary neurologic condition or one that does not originate in the central nervous system. Optimal management of such conditions requires high clinical suspicion and a broad differential diagnosis, which facilitates rapid recognition and effective treatment. A thorough history and physical examination are key determinants in accurately diagnosing neurologic conditions associated with fever, often requiring acquisition of collateral information from persons other than the patient.

Pediatric lumbar puncture and cerebrospinal fluid analysis

BACKGROUND

Lumbar puncture (LP) is a commonly performed procedure in pediatrics. Accurate analysis of cerebrospinal fluid (CSF) profile is essential in diagnosing and managing a variety of infectious and inflammatory conditions involving the brain, meninges, and spinal cord. It can also provide useful diagnostic information in the evaluation of possible subarachnoid hemorrhage and demyelinating syndromes, and aid in the diagnosis and management of pseudotumor cerebri.

OBJECTIVES

To review anatomic, physiologic, and pathologic aspects of performing pediatric lumbar puncture and CSF analysis.

DISCUSSION

Although still a commonly performed procedure in the outpatient setting, effective vaccines to prevent invasive infection due to Streptococcus pneumoniae and Haemophilus influenzae type b have greatly reduced pediatric bacterial meningitis rates due to these pathogens, resulting in decreased opportunity for physician-trainees to perfect this important skill (among nonneonates) during the 3 years of supervised residency training. Success in performing pediatric LP is augmented by a thorough understanding of medical aspects related to this procedure. This article discusses technical aspects involved in successfully performing a lumbar puncture to obtain CSF, and interpreting a CSF profile in children.

CONCLUSION

A thorough understanding of anatomic, physiologic, and pathologic considerations regarding performing lumbar puncture and CSF analysis can augment success in diagnosing a variety of potentially serious pediatric conditions.

Neuraxial Anesthesia in Parturients with Intracranial Pathology

Parturients with intracranial lesions are often assumed to have increased intracranial pressure, even in the absence of clinical and radiographic signs. The risk of herniation after an inadvertent dural puncture is frequently cited as a contraindication to neuraxial anesthesia. This article reviews the relevant literature on the use of neuraxial anesthesia in parturients with known intracranial pathology, and proposes a framework and recommendations for assessing risk of neurologic deterioration, with epidural analgesia or anesthesia, or planned or inadvertent dural puncture. The authors illustrate these concepts with numerous case examples and provide guidance for the practicing anesthesiologist in determining the safety of neuraxial anesthesia.

Intramedullary spinal cord abscess as complication of lumbar puncture: a case-based update

INTRODUCTION

Although lumbar puncture (LP) is a relatively straightforward procedure and is usually associated with low morbidity, rare and significant neurological complications can occur. Intramedullary spinal cord abscess (ISCA) after lumbar puncture is one of these serious complications; however, this complication has not yet been reported in children.

CASE REPORT

After 27 days in another medical facility, a 1-year-old girl was admitted to our hospital with a diagnosis of fever of unknown origin. Prior to the second admission, she had undergone multiple traumatic LP attempts. The patient was referred to our institution with progressive and ascending weakness. Three days later, this weakness involved all of the patient's four limbs. A LP was performed and showed purulent cerebrospinal fluid (CSF). An emergent spinal magnetic resonance imaging was performed and revealed an intramedullary lesion extending from the T2 to L3 level. Broad-spectrum antibiotics and steroids were administered to the patient, and a T2-L3 laminectomy was performed. The postoperative course was uneventful, but a neurologic deficit, including lower limb paralysis, remained.

CONCLUSION

The index of suspicion for a pyogenic infection of the intramedullary space should be higher if progressive flaccid paralysis develops within a few days after a lumbar procedure. Nevertheless, the diagnosis may be challenging due to the rarity of this condition. Any misdiagnosis or delay of adequate treatment may lead to unfavorable outcomes.