Cranial Imaging Before Lumbar Puncture in Adults With Community-Acquired Meningitis: Clinical Utility and Adherence to the Infectious Diseases Society of America Guidelines

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.

Clinical variation in the early assessment and management of suspected community-acquired meningitis: a multicentre retrospective study

BACKGROUND

Bacterial meningitis is a medical emergency and timely management has been shown to improve outcomes. The aim of this study was to compare the early assessment and management of adults with suspected community-onset meningitis between hospitals and identify opportunities for clinical practice improvement.

METHODS

This retrospective cohort study was conducted at three principal referral hospitals in Sydney, Australia. Adult patients with suspected meningitis undergoing cerebrospinal fluid sampling between 1 July 2018 and 31 June 2019 were included. Relevant clinical and laboratory data were extracted from the medical record. Differences between sites were analysed and factors associated with time to antimicrobial therapy were assessed by Cox regression.

RESULTS

In 260 patients, the median time from triage to antibiotic administration was 332 min with a difference of up to 147 min between hospitals. Median time from triage to lumbar puncture (LP) was 366 min with an inter-hospital difference of up to 198 min. Seventy per cent of patients had neuroimaging prior to LP, and this group had a significantly longer median time to antibiotic administration (367 vs 231 min; P = 0.001). Guideline concordant antibiotics were administered in 84% of patients, with only 39% of those administered adjunctive corticosteroids. Seven (3%) patients had confirmed bacterial meningitis. Modifiable factors associated with earlier antimicrobial administration included infectious diseases involvement (adjusted hazard ratio [aHR], 1.50 [95% confidence interval (CI), 1.01-2.24]) and computed tomography (CT) scanning (aHR, 0.67 [95% CI, 0.46-0.98]).

CONCLUSION

Opportunities for improvement include reducing the time to LP and antibiotic administration, improving coadministration of corticosteroids and avoiding potentially unnecessary CT scanning.

High risk and low prevalence diseases: Adult bacterial meningitis

INTRODUCTION

Acute bacterial meningitis in adults is a rare but serious condition that carries a high rate of morbidity.

OBJECTIVE

This review highlights pearls and pitfalls of acute bacterial meningitis in adults, including presentation, diagnosis, and management in the emergency department (ED) based on current evidence.

DISCUSSION

Meningitis encompasses a broad spectrum of disease involving inflammation of the meninges and subarachnoid space. It classically presents with fever, nuchal rigidity, and altered mental status, but this triad is not present in all cases. Up to 95% of patients will have at least two of the following four cardinal symptoms: fever, nuchal rigidity, altered mental status, and headache. The most common bacterial etiologies are S. pneumoniae and N. meningitidis. Cerebrospinal fluid testing obtained by lumbar puncture remains the gold standard in diagnosis. Head computed tomography prior to lumbar puncture may not be necessary in most patients. Empiric treatment consists of vancomycin, ceftriaxone, and dexamethasone. Elevated intracranial pressure should be managed using established neurocritical care strategies.

CONCLUSION

A better understanding of the pearls and pitfalls of acute bacterial meningitis can assist emergency clinicians in pursuing its timely diagnosis and management.

Neuroimaging Patterns of Intracranial Infections: Meningitis, Cerebritis, and Their Complications

Neuroimaging provides rapid, noninvasive visualization of central nervous system infections for optimal diagnosis and management. Generalizable and characteristic imaging patterns help radiologists distinguish different types of intracranial infections including meningitis and cerebritis from a variety of bacterial, viral, fungal, and/or parasitic causes. Here, we describe key radiologic patterns of meningeal enhancement and diffusion restriction through profiles of meningitis, cerebritis, abscess, and ventriculitis. We discuss various imaging modalities and recent diagnostic advances such as deep learning through a survey of intracranial pathogens and their radiographic findings. Moreover, we explore critical complications and differential diagnoses of intracranial infections.

Is Contrast-Enhanced Computed Tomography Redundant for Suspected Intracranial Infection in the Emergency Setting?

OBJECTIVE

There are currently no guidelines for when to use intravenous contrast with head computed tomography (CT) when there is suspected acute intracranial infection. The purpose of our study was to determine the proportion of cases with enhancing findings on CT that also have conspicuous correlating associated findings on noncontrast CT, which would have on their own merited further evaluation with magnetic resonance imaging, the criterion standard for evaluating central nervous system pathology.

METHODS

A retrospective keyword search of the history and clinical information fields in radiology reports for CT examinations of the head without and with contrast from the period January 1, 2004, to October 31, 2021 was performed. Patients with prior head surgery or a history of cancer were excluded. For remaining patients, the noncontrast CT was reviewed for vasogenic edema or mass effect as markers of a possible acute infection, and the presence of background hypodense white matter changes was noted and graded as either absent, mild/scattered, or confluent. Subsequently, the companion contrast-enhanced CT was reviewed for an enhancing abnormality. Chart review was performed to confirm that an infectious process was the ultimate clinical diagnosis in patients with enhancing abnormalities.

RESULTS

Of 343 patients meeting study inclusion/exclusion criteria, 39 had acute infections with an enhancing abnormality on CT (prevalence 11.3%). Thirty-two of these 39 patients also had correlative findings on the noncontrast CT. Noncontrast CT had a positive predictive value of 100%, negative predictive value of 97.7%, sensitivity of 82.1%, specificity of 100%, and accuracy of 98.0% for detecting markers (vasogenic edema and/or mass effect) associated with an enhancing abnormality. Vasogenic edema was the most common noncontrast CT finding in patients who had an infectious enhancing lesion (32 of 39), followed by mass effect (22 of 39). The 7 cases where the acute infection was occult on noncontrast CT were due to leptomeningitis (n = 3), confluent background white matter changes masking the vasogenic edema surrounding intra-axial lesions (n = 3), and a small 0.5 cm extra-axial abscess.

CONCLUSIONS

Most acute intracranial infections with an enhancing CT finding also have a correlative conspicuous noncontrast finding that on its own would merit further evaluation with magnetic resonance imaging, the criterion standard for investigating central nervous system disease, and therefore, in the setting of suspected intracranial infection, contrast-enhanced CT is redundant in most cases. Contrast-enhanced CT primarily provides diagnostic benefit in patients with confluent background white matter changes that may mask vasogenic edema on noncontrast CT.

Progress and Challenges in Bacterial Meningitis: A Review

IMPORTANCE

Bacterial meningitis is a worldwide health problem, with incidence rates ranging from approximately 0.9 per 100 000 individuals per year in high-income countries to 80 per 100 000 individuals per year in low-income countries. In low-income countries, bacterial meningitis has a mortality rate of up to 54%. Up to 24% of those who survive develop chronic neurological sequelae, such as hearing loss or focal neurological deficits.

OBSERVATIONS

Streptococcus pneumoniae causes about 72% and Neisseria meningitidis causes about 11% of cases of bacterial meningitis in people older than 16 years. Escherichia coli and Streptococcus agalactiae cause about 35% of cases of early-onset neonatal meningitis. In adults, risk factors for bacterial meningitis include older age and immunosuppressive conditions. The most common symptoms are headache (84%), fever (74%), stiff neck (74%), altered mental status (median [IQR] Glasgow Coma Scale score of 11 [9-14] on a scale ranging from 3-15), and nausea (62%). Brain imaging should be performed before lumbar puncture if patients present with altered mental status, focal neurological deficits, papilledema, or history of immunocompromising conditions or central nervous system disease. Bacterial meningitis should be suspected if any of the following are present on admission: serum leukocytes greater than 10.0 ×109/L, cerebrospinal fluid (CSF) leukocytes greater than 2000/μL, CSF granulocytes greater than 1180/μL, CSF protein greater than 2.2 g/L, CSF glucose less than 34.23 mg/dL, or fever. A positive Gram stain result for bacteria is diagnostic, but the sensitivity of a positive Gram stain result for bacterial meningitis ranges from 50% to 90%. In countries in which the prevalence of ceftriaxone-resistant Streptococcus pneumoniae exceeds 1%, vancomycin and ceftriaxone are the empirical antibiotics of choice, with the addition of ampicillin in neonates, older patients, and immunocompromised patients. Adjunctive dexamethasone should be used in patients with bacterial meningitis but stopped if Listeria monocytogenes is confirmed.

CONCLUSIONS AND RELEVANCE

Bacterial meningitis affects approximately 0.9 per 100 000 individuals to 80 per 100 000 individuals per year and has a mortality rate as high as 54%. First-line therapy is prompt empirical intravenous antibiotic therapy and adjunctive dexamethasone.

Early Intracranial Hemorrhage Predicts Poor Clinical Outcome in Community-Acquired Bacterial Meningitis

Background

Community-acquired bacterial meningitis in adults is associated with significant morbidity and mortality; therefore, early prognostication is important to identify severe cases and possibly allocate more intensive treatment. We hypothesized that early intracranial hemorrhage portends a poor prognosis. The objective of this study was to evaluate the prognostic impact of early intracranial hemorrhage regardless of size and location on clinical outcome.

Methods

Retrospective analysis of patients with community-acquired bacterial meningitis treated at a tertiary academic center between 2009 and 2019 about patient characteristics, cerebral imaging findings, and clinical outcome. Uni- and multivariable logistic regression analyses were performed to identify independent predictors of poor clinical outcomes defined as a modified Rankin scale score of 5 or 6 upon discharge.

Results

A total of 102 patients were included, of which 22.5% had poor clinical outcomes. Intracranial micro- or macrohemorrhages were present in 7.8% of cases and associated with poor clinical outcomes [odds ratio (OR) 55.75, 95% CI 3.08–1,008.48, p = 0.006] in multivariate analysis, further predictors included ischemic stroke (OR 15.06, 95% CI 1.32–172, p = 0.029), age (OR 2.56, 95% CI 1.4–4.67, p = 0.002), and reduced consciousness (OR 4.21, 95% CI 1.07–16.64, p = 0.04).

Conclusion

Early cerebral hemorrhage (ECHO) is a potential prognostic marker for clinicians confronted with decision-making in patients who are critically ill with community-acquired bacterial meningitis.

Aseptic Meningitis and Its Viral Etiologies, Clinical Characteristics and Management Practices in Children: A Retrospective Hospital-Based Study From Jordan

Purpose In this study, we aimed to describe the clinical characteristics, laboratory findings, aetiologies, and role of PCR in the decision on the management plan and duration of hospital stay in Jordanian children diagnosed with aseptic meningitis. Methods This retrospective observational cohort study included children diagnosed with meningitis who were admitted to the paediatric ward at Jordan University Hospital (JUH) during the period from January 2016 to August 2020. Patients were identified through the ICD9 discharge code of meningitis. Patients diagnosed with aseptic meningitis (defined as a patient with signs and symptoms of meningitis with a cerebrospinal fluid (CSF) white cell count of >5 cells/mm3, and a negative CSF Gram stain) were included, while patients who had low CSF glucose (<50% of serum) positive cerebrospinal fluid Gram stain and/or culture for bacterial meningitis were excluded. Files were reviewed to collect data on the clinical picture, viruses identified by the CSF viral polymerase chain reaction (PCR) panel, duration of medication, and hospital stay in patients with identified virus versus those with negative viral PCR. Results One hundred and thirty-one patients were included: 87 males (66.4%) and 44 females (33.5%). Fever was the most common presenting symptom, followed by headache, vomiting, and excessive sleep in 48.0%, 42.7%, and 35.8% of the patients, respectively. Prior oral antibiotic use was reported in 48/125 (38.4%) patients. White blood cell count (WBC) ranged from 4.800 to 22.000. cells/mL, 45 patients (34.3%) had counts above 15.000 cells/mL. C-reactive protein level was high in 61/103 (59.2%) patients. CSF WBC count was <100 in 62 (47.3%) patients while neutrophils predominance of >70% was present in 27 (20.6%) patients. Viral panel PCR was done for 100/131 (76.3%) patients and was positive in 66/100 (66%) patients; with enterovirus being the most common identified viruses (60/100; 60%). The average duration of hospital stay was 5.9 and 5.5 days for those with negative and positive PCR respectively. Ten (7.6%) patients had seizures upon presentation. None of the patients had any neurological sequel related to his meningitis. Conclusion Enteroviruses are the most common identified cause of paediatric aseptic meningitis in Jordan. Although PCR revealed an identified virus in around half of the patients, nevertheless, there was no adjustment in the management plan regarding duration of empirical antibiotic use and hospital stay. Increasing knowledge and awareness among clinicians on viral meningitis' lab characteristics might have great impact on duration of hospital stay and thus would be reflected on the patient and the healthcare system as well.

Comparison of Four International Guidelines on the Utility of Cranial Imaging Before Lumbar Puncture in Adults with Bacterial Meningitis

BACKGROUND

International guidelines exist for obtaining a head computed tomography (CT) scan before a lumbar puncture (LP) in adults with suspected meningitis but there are no studies comparing them in their ability to identify intracranial abnormalities.

METHODS

A retrospective study of 202 cases of adults with community-acquired bacterial meningitis at 16 hospitals in Houston from December 2004 until May 2019 to compare the 4 guidelines' ability in identifying minor and major intracranial findings, cases in which CT findings changed management, and patients who suffered cerebral herniation.

RESULTS

Minor and major intracranial findings were seen in 69 (34.1%) and in 24 (11.8%) of the patients, respectively. A total of nine (37.5%) of the major intracranial findings prompted a neurosurgical intervention. A total of four (1.9%) patients had cerebral herniation. The Infectious Diseases of America (IDSA), the United Kingdom (UK), the European Society of Clinical Microbiology and Infectious Diseases (ESCMID), and the Swedish guidelines for cranial imaging were met in 92.1%, 54%, 41.6%, and in 23.3% of the patients, respectively. The IDSA, UK, European, and the Swedish guidelines missed 0%, 20.8%, 41.7%, and 70.8% of the major intracranial findings and 0, 1, 3 and 4 of the 9 patients that prompted a neurosurgical intervention, respectively. All four patients with cerebral herniation met the criteria for all four guidelines.

CONCLUSION

Out of the four international guidelines, only the IDSA recommendations for cranial imaging did not miss any major intracranial abnormality or any finding that prompted a neurosurgical intervention but all guidelines identified herniation.

Infectious Meningitis and Encephalitis

Infectious meningitis and encephalitis are associated with significant morbidity and mortality worldwide. Acute bacterial meningitis is rapidly fatal and early recognition and institution of therapy are imperative. Viral meningitis is typically a benign self-limited illness. Chronic meningitis (defined as presenting with >4 weeks of symptoms) is most often caused by tuberculosis and fungal infection. Because the diagnostic testing for tuberculous meningitis is insensitive and cultures often take weeks to grow, therapy is often initiated empirically when the diagnosis is suspected. Human simplex virus encephalitis is the most common cause of encephalitis and requires prompt treatment with intravenous acyclovir.

Neuroradiology of infectious diseases

PURPOSE OF REVIEW

Early diagnosis of central nervous system (CNS) infections is crucial given high morbidity and mortality. Neuroimaging in CNS infections is widely used to aid in the diagnosis, treatment and to assess the response to antibiotic and neurosurgical interventions.

RECENT FINDINGS

The Infectious Diseases Society of America (IDSA) guidelines have clear recommendations for obtaining a computerized tomography of the head (CTH) prior to lumbar puncture (LP) in suspected meningitis. In the absence of indications for imaging or in aseptic meningitis, cranial imaging is of low utility. In contrast, cranial imaging is of utmost importance in the setting of encephalitis, bacterial meningitis, ventriculitis, bacterial brain abscess, subdural empyema, epidural abscess, neurobrucellosis, neurocysticercosis, and CNS tuberculosis that can aid clinicians with the differential diagnosis, source of infection (e.g., otitis, sinusitis), assessing complications of meningitis (e.g., hydrocephalus, venous sinus thrombosis, strokes), need for neurosurgical interventions and to monitor for the response of therapy. Novel imaging techniques such as fast imaging employing steady-state acquisition (FIESTA), susceptibility-weighted imaging (SWI), and chemical exchange saturation transfer (CEST) contrast are briefly discussed.

SUMMARY

Though the radiological findings in CNS infections are vast, certain patterns along with clinical clues from history and examination often pave the way to early diagnosis. This review reiterates the importance of obtaining cranial imaging when necessary, and the various radiological presentations of commonly encountered CNS infections.

Acute bacterial meningitis

Purpose of review

Community-acquired bacterial meningitis is a continually changing disease. This review summarises both dynamic epidemiology and emerging data on pathogenesis. Updated clinical guidelines are discussed, new agents undergoing clinical trials intended to reduce secondary brain damage are presented.

Recent findings

Conjugate vaccines are effective against serotype/serogroup-specific meningitis but vaccine escape variants are rising in prevalence. Meningitis occurs when bacteria evade mucosal and circulating immune responses and invade the brain: directly, or across the blood–brain barrier. Tissue damage is caused when host genetic susceptibility is exploited by bacterial virulence. The classical clinical triad of fever, neck stiffness and headache has poor diagnostic sensitivity, all guidelines reflect the necessity for a low index of suspicion and early Lumbar puncture. Unnecessary cranial imaging causes diagnostic delays. cerebrospinal fluid (CSF) culture and PCR are diagnostic, direct next-generation sequencing of CSF may revolutionise diagnostics. Administration of early antibiotics is essential to improve survival. Dexamethasone partially mitigates central nervous system inflammation in high-income settings. New agents in clinical trials include C5 inhibitors and daptomycin, data are expected in 2025.

Summary

Clinicians must remain vigilant for bacterial meningitis. Constantly changing epidemiology and emerging pathogenesis data are increasing the understanding of meningitis. Prospects for better treatments are forthcoming.

Cranial Imaging and Lumbar Puncture in Patients With Suspected Central Nervous System Infection

BACKGROUND

Performing cranial imaging prior to lumbar punctures (LPs) in patients with suspected central nervous system (CNS) infections has been associated with delayed treatments and poor outcomes. Various guidelines provide different criteria for cranial imaging prior to LP.

METHODS

We describe the use of cranial imaging in a cohort of adult patients with suspected CNS infections, and evaluated adherence to the recommendations made in the Infectious Disease Society of America (IDSA), European Society of Clinical Microbiology and Infectious Diseases (ESCMID), Swedish, and Dutch guidelines. We also analyzed the association between cranial imaging and the time between emergency department entrance and intravenous antibiotic administration.

RESULTS

From 2012-2015, 203 patients with suspected CNS infections were included, of whom 56 (27%) were diagnosed with CNS infections and 16 were diagnosed with bacterial meningitis (8%). Cranial imaging, in all cases computed tomography (CT), was performed in 130 patients (64%) and led to the deferral of LPs in 7 (5%). Criteria by the IDSA, ESCMID, Swedish, and Dutch guidelines showed indications for imaging in 64%, 39%, 39%, and 40% of patients, respectively. The times between emergency department arrivals and the start of antibiotic therapy between patients with and without CT before LP were similar (median 134 [interquartile range (IQR) 58-292] vs. 141 minutes [IQR 52-227], respectively; Mann-Whitney U P = .74).

CONCLUSIONS

A cranial CT prior to LP was done in the majority of patients with a suspected CNS infection, irrespective of guideline indications. The ESCMID, Swedish, and Dutch guidelines were more restrictive in advising imaging, compared to the IDSA guidelines. Performing cranial imaging prior to LP was not associated with treatment delays in this Dutch cohort study.

Lumbar Puncture: Indications, Challenges and Recent Advances

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Headache in the Emergency Department: Avoiding Misdiagnosis of Dangerous Secondary Causes, An Update

In the initial assessment of the headache patient, the emergency physician must consider several dangerous secondary causes of headache. A thorough history and physical examination, along with consideration of a comprehensive differential diagnosis may alert the emergency physician to the diagnosis of a secondary headache particularly when the history is accompanied by any of the following clinical features: sudden/severe onset, focal neurologic deficits, altered mental status, advanced age, active or recent pregnancy, coagulopathy, malignancy, fever, visual deficits, and/or loss of consciousness.

Update and advances in community acquired bacterial meningitis

PURPOSE OF REVIEW

Community-acquired bacterial meningitis continues to occur and be associated with significant morbidity and mortality despite the availability of effective conjugate vaccines for the three most important meningeal pathogens.

RECENT FINDINGS

Indications for cranial imaging in suspected bacterial meningitis varies significantly between guidelines. Cranial imaging is of no clinical utility in those patients without indications and fosters delays in performing a lumbar puncture. Delaying lumbar puncture is associated with increased costs in both adults and children with meningitis and previous antibiotic therapy impacts the yield of microbiological results. Delaying antibiotic therapy is associated with worse clinical outcomes. Adjunctive steroids have reduced the mortality of adults with pneumococcal meningitis but have been associated with increased adverse outcomes in Listeria monocytogenes and Cryptococcus neoformans.

SUMMARY

Community-acquired bacterial meningitis remains a global health concern with high morbidity and mortality especially in low-income countries. Cranial imaging should be done only in patients with an indication with an attempt to do a prompt lumbar puncture and to initiate antibiotic therapy and adjunctive steroids as soon as possible to improve clinical outcomes.

Update on the "Choosing Wisely" initiative in infectious diseases in Germany

Purpose

The Choosing Wisely^® initiative is an international campaign addressing over- and underuse of diagnostic and therapeutic measures in infectious diseases among others. Since 2016, the German Society for Infectious Diseases (DGI) has constantly designed new items in this regard. Here we report the most recent recommendations.

Methods

The recommendations of the DGI are part of the “Klug entscheiden” initiative of the German Society of Internal Medicine (DGIM). Topics for the new items were suggested by members of the DGI, checked for scientific evidence and consented within the DGI and the DGIM before publication.

Results

The new recommendations are: (1) individuals with immune-suppression, advanced liver cirrhosis or renal insufficiency should receive a dual pneumococcal vaccination. (2) In case of positive blood cultures with Candida spp. thorough diagnostics and treatment should be initiated. (3) In case of suspected meningitis, adult patients should receive dexamethasone and antibiotics immediately after venipuncture for blood cultures and before potential imaging. (4) In case of suspected meningitis a CT scan before lumbar puncture should not be ordered—except for symptoms indicating high CSF pressure or focal brain pathology or in cases of severe immune-suppression. (5) In patients with suspected severe infections, a minimum of two pairs of blood cultures should be drawn using separate venipunctures prior to antibiotic therapy—regardless of body temperature. There is no need of a minimum time interval in between the blood draws.

Conclusion

Applying these new Choosing Wisely^® recommendations will increase patient safety and the value of health care.

Lumbar Puncture Performed Promptly or After Neuroimaging in Acute Bacterial Meningitis in Adults: A Prospective National Cohort Study Evaluating Different Guidelines

Background

Early treatment is pivotal for favorable outcome in acute bacterial meningitis (ABM). Lumbar puncture (LP) is the diagnostic key. The aim was to evaluate the effect on outcome of adherence to European Society of Clinical Microbiology and Infectious Diseases (ESCMID), Infectious Diseases Society of America (IDSA), and Swedish guidelines regarding neuroimaging before LP.

Methods

The cohort comprised 815 adult ABM patients in Sweden registered prospectively between 2008 and 2015. Primary endpoint was in-hospital mortality and secondary endpoint was favorable outcome at 2-6 months of follow-up.

Results

Indications for neuroimaging before LP existed in 7%, 32%, and 65% according to Swedish, ESCMID, and IDSA guidelines, respectively. The adjusted odds ratio (aOR) was 0.48 (95% confidence interval [CI], .26-.89) for mortality and 1.52 (95% CI, 1.08-2.12) for favorable outcome if Swedish guidelines were followed. ESCMID guideline adherence resulted in aOR of 0.68 (95% CI, .38-1.23) for mortality and 1.05 (95% CI, .75-1.47) for favorable outcome. Following IDSA recommendations resulted in aOR of 1.09 (95% CI, .61-1.95) for mortality and 0.59 (95% CI, .42-.82) for favorable outcome. Performing prompt vs neuroimaging-preceded LP was associated with aOR of 0.38 (95% CI, .18-.77) for mortality and 2.11 (95% CI, 1.47-3.00) for favorable outcome. The beneficial effect of prompt LP was observed regardless of mental status and immunosuppression.

Conclusions

Adherence to Swedish guidelines in ABM is associated with decreased mortality and increased favorable outcome in contrast to adherence to ESCMID or IDSA recommendations. Our findings support that impaired mental status and immunocompromised state should not be considered indications for neuroimaging before LP in patients with suspected ABM.

Aseptic meningitis in adults and children: Diagnostic and management challenges

BACKGROUND

Aseptic meningitis represents a common diagnostic and management dilemma to clinicians.

OBJECTIVES

To compare the clinical epidemiology, diagnostic evaluations, management, and outcomes between adults and children with aseptic meningitis.

STUDY DESIGN

We conducted a retrospective study from January 2005 through September 2010 at 9 Memorial Hermann Hospitals in Houston, TX. Patients age≥2months who presented with community-acquired aseptic meningitis with a CSF white blood cell count >5cells/mm³ and a negative Gram stain and cultures were enrolled. Patients with a positive cryptococcal antigen, positive blood cultures, intracranial masses, brain abscesses, or encephalitis were excluded.

RESULTS

A total of 509 patients were included; 404 were adults and 105 were children. Adults were most likely to be female, Caucasian, immunosuppressed, have meningeal symptoms (headache, nausea, stiff neck, photophobia) and have a higher CSF protein (P <0.05). In contrast, children were more likely to have respiratory symptoms, fever, and leukocytosis (P <0.05). In 410 (81%) patients, the etiologies remained unknown. Adults were more likely to be tested for and to have Herpes simplex virus and West Nile virus while children were more likely to be tested for and to have Enterovirus (P <0.001). The majority of patients were admitted (96.5%) with children receiving antibiotic therapy more frequently (P <0.001) and adults receiving more antiviral therapy (P=0.001). A total of 384 patients (75%) underwent head CT scans and 125 (25%) MRI scans; all were normal except for meningeal enhancement. All patients had a good clinical outcome at discharge.

DISCUSSION

Aseptic meningitis in adults and children represent a management challenge as etiologies remained unknown for the majority of patients due to underutilization of currently available diagnostic techniques.