Attainment of target rifampicin concentrations in cerebrospinal fluid during treatment of tuberculous meningitis

Central nervous system tuberculosis in Western Sydney: a 10-year retrospective cohort study

BACKGROUND

Central nervous system tuberculosis (CNS-TB) is a rare complication of tuberculosis. There is a lack of data surrounding investigation and management of this in Australia.

AIM

To review CNS-TB cases in Western Sydney, Australia, and understand the epidemiology, investigation, diagnosis, management and outcomes in a low-prevalence setting.

METHODS

Retrospective cohort study of all CNS-TB patients managed in Western Sydney from 2013 to 2022. Demographics, risk factors, clinical presentation, investigations and management were reviewed. Clinical outcomes like hospital length-of-stay, adverse drug reactions, paradoxical reactions, functional disability and treatment outcomes, including cure, treatment failure, loss to follow-up and death, were also measured.

RESULTS

Thirty-nine CNS-TB cases were identified, with 16 (41%) confirmed by nucleic acid amplification test or culture of CNS specimens and 23 (59%) diagnosed presumptively without CNS microbiological confirmation. The median age was 32 years. Thirty-seven (95%) were overseas-born; 27 (69%) had no comorbidities. Presenting symptoms included fever (82%), headache (64%) and weight loss (51%). Twenty-five (64%) used fluoroquinolones and nine (23%) used high-dose rifampicin. Steroids were used in all patients. Six (15%) were prescribed aspirin for primary stroke prevention. Twenty-eight (73%) completed treatment, with one requiring re-treatment for presumed treatment failure. Six (15%) were lost to follow-up, and five (13%) died during their treatment course. Twenty-one (54%) experienced an adverse drug reaction.

CONCLUSION

Tuberculosis is an ongoing public health issue in Australia, with CNS-TB being its most devastating form, and all clinicians to be aware of this rare complication. The efficacy of newer treatment options requires further study.

Extracorporeal membrane oxygenation in acute respiratory distress syndrome caused by elderly tuberculous meningitis: a case report and review of the literature

Diagnosing and clinical management of tuberculous meningitis (TBM) are still challenging for clinicians. Analysis of cerebrospinal fluid (CSF) is an important diagnostic tool for patients with suspected central nervous system (CNS) diseases. Acute respiratory distress syndrome (ARDS), an inflammatory lung injury, can be treated by mechanical ventilation, fluid management, and even extracorporeal membrane oxygenation (ECMO). In addition, metagenomic next-generation sequencing (mNGS) can facilitate the detection of atypical, rare pathogens in clinical specimens. We report a case of a 65-year-old man with ARDS caused by TBM. He was admitted with a fever and shaking. Despite aggressive initial treatment, the patient progressed rapidly and developed ARDS. Without positive results of mNGS and culture, anti-tuberculosis (TB) treatment was started. In order to improve oxygenation levels, he was placed on veno-venous ECMO for 8 days. On day 47, the tracheotomy catheter was pulled out and sealed. The patient was conscious and could communicate with family members as normal.

Comprehensive Therapeutic Approaches to Tuberculous Meningitis: Pharmacokinetics, Combined Dosing, and Advanced Intrathecal Therapies

Tuberculous meningitis (TBM) presents a critical neurologic emergency characterized by high mortality and morbidity rates, necessitating immediate therapeutic intervention, often ahead of definitive microbiological and molecular diagnoses. The primary hurdle in effective TBM treatment is the blood-brain barrier (BBB), which significantly restricts the delivery of anti-tuberculous medications to the central nervous system (CNS), leading to subtherapeutic drug levels and poor treatment outcomes. The standard regimen for initial TBM treatment frequently falls short, followed by adverse side effects, vasculitis, and hydrocephalus, driving the condition toward a refractory state. To overcome this obstacle, intrathecal (IT) sustained release of anti-TB medication emerges as a promising approach. This method enables a steady, uninterrupted, and prolonged release of medication directly into the cerebrospinal fluid (CSF), thus preventing systemic side effects by limiting drug exposure to the rest of the body. Our review diligently investigates the existing literature and treatment methodologies, aiming to highlight their shortcomings. As part of our enhanced strategy for sustained IT anti-TB delivery, we particularly seek to explore the utilization of nanoparticle-infused hydrogels containing isoniazid (INH) and rifampicin (RIF), alongside osmotic pump usage, as innovative treatments for TBM. This comprehensive review delineates an optimized framework for the management of TBM, including an integrated approach that combines pharmacokinetic insights, concomitant drug administration strategies, and the latest advancements in IT and intraventricular (IVT) therapy for CNS infections. By proposing a multifaceted treatment strategy, this analysis aims to enhance the clinical outcomes for TBM patients, highlighting the critical role of targeted drug delivery in overcoming the formidable challenges presented by the blood-brain barrier and the complex pathophysiology of TBM.

Tissue Penetration of Antimicrobials in Intensive Care Unit Patients: A Systematic Review-Part II

In patients that are admitted to intensive care units (ICUs), the clinical outcome of severe infections depends on several factors, as well as the early administration of chemotherapies and comorbidities. Antimicrobials may be used in off-label regimens to maximize the probability of therapeutic concentrations within infected tissues and to prevent the selection of resistant clones. Interestingly, the literature clearly shows that the rate of tissue penetration is variable among antibacterial drugs, and the correlation between plasma and tissue concentrations may be inconstant. The present review harvests data about tissue penetration of antibacterial drugs in ICU patients, limiting the search to those drugs that mainly act as protein synthesis inhibitors and disrupting DNA structure and function. As expected, fluoroquinolones, macrolides, linezolid, and tigecycline have an excellent diffusion into epithelial lining fluid. That high penetration is fundamental for the therapy of ventilator and healthcare-associated pneumonia. Some drugs also display a high penetration rate within cerebrospinal fluid, while other agents diffuse into the skin and soft tissues. Further studies are needed to improve our knowledge about drug tissue penetration, especially in the presence of factors that may affect drug pharmacokinetics.

Intensified Antituberculosis Therapy Regimen Containing Higher Dose Rifampin for Tuberculous Meningitis: A Systematic Review and Meta-Analysis

Background

Tuberculous meningitis is difficult to diagnose and is associated with high mortality. Recently, several studies evaluated the intensified regimen containing higher dose rifampin to treat tuberculous meningitis. However, this topic remains to be concluded. Therefore, this systematic review and meta-analysis was conducted to evaluate pharmacokinetics parameters, safety, and survival benefits of high-dose rifampin for tuberculous meningitis.

Method

Data were searched from PubMed, EMBASE, The Cochrane Library, and Web of Science for studies describing an antituberculosis regimen including a higher dose of rifampin for patients with tuberculous meningitis. The quality of eligible studies was evaluated via The Cochrane Risk of Bias Tool. The meta-analysis was performed by Review Manager 5.3 software, the synthesis of the data was shown in mean difference (MD) or relative risk (RR), and 95% confidence intervals (CIs).

Results

There were six randomized control trails included in this meta-analysis. The results showed that the concentration in plasma and cerebrospinal fluid (CSF) were significantly higher in the intervention group than the standard group [MD = 22.08, 95%CI (16.24, 27.92), p < 0.00001; MD = 0.74, 95%CI (0.42, 1.05), p < 0.00001], as well as the area under the time concentration curve between 0 and 24 h (AUC₀₋₂₄) of rifampin [MD 203.56, 95%CI (153.07, 254.05), p < 0.00001] in plasma, but the overall survival did not improve [RR = 0.92, 95%CI (0.67, 1.26), p = 0.61]. For adverse events, the results showed a statistically significant lower incidence of hypersensitivity compared with the intervention group [RR = 1.72, 95%CI (1.13, 2.62), p = 0.01]. Fortunately, other common adverse drug reactions such as liver injury, neurological events, myelosuppression, and cardiotoxicity had no significant increase [RR = 0.98, 95%CI (0.77, 1.26), p = 0.90; RR = 1.10, 95%CI (0.94, 1.30), p = 0.23; RR = 0.82, 95%CI (0.59, 1.13), p = 0.22; RR = 1.11, 95%CI (0.66, 1.86), p = 0.70].

Conclusion

This meta-analysis suggested that the intensified treatment regimen including a higher dose of rifampin significantly increased the rifampin concentration both in the plasma and CSF, and it was safe in patients with tuberculous meningitis, but resulted in no improvement in survival rates.

High-dose rifampicin for the treatment of tuberculous meningitis: a meta-analysis of randomized controlled trials

WHAT IS KNOWN AND OBJECTIVE

Tuberculous meningitis (TBM) is one of the most serious types of extrapulmonary tuberculosis and has caused distress to human. Effective treatment is particularly important. The aim of this meta-analysis is to compare the efficacy of high-dose and standard-dose rifampicin.

METHODS

Databases including PubMed, Web of Science, Embase, Scopus and the Cochrane Library databases were electronically searched to identify randomized controlled trials that reported high-dose rifampicin in treatment of patients with TBM. The retrieval time is limited from inception to June 2021. Two reviewers independently screened literature, extracted data and assessed risk bias of included studies. Meta-analysis was performed by using STATA 12.0 software.

RESULTS AND DISCUSSION

A total of 12 studies involving 1596 patients were included. The meta-analysis results showed no significant differences in 6-month mortality, 9-month mortality, Grade I-II AE, Grade III-V AE, hepatotoxicity, hepatotoxicity Grade I-II and cardiologic events between high-dose rifampicin (or high-dose rifampicin plus moxifloxacin or levofloxacin) and standard-dose groups. The log(C_max ) (WMD 0.69, 95%CI 0.59-0.79, p 0.001) and log(AUC_0-24h ) (WMD 0.79, 95%CI 0.71-0.88, p 0.001) were higher with high-dose rifampicin. Subgroup analysis revealed the rise of log(C_max ) in high-dose rifampicin orally was consistent with intravenous administration compared with the control (WMD 0.69, 95%CI 0.66-0.73, p 0.001).

WHAT IS NEW AND CONCLUSION

High-dose rifampicin was not a protective factor for 6-month mortality, despite increased plasma C_max and AUC_0-24h . However, the above conclusions are still required to be verified through more RCTs due to the limited quantity of included studies.

Central nervous system infections and antimicrobial resistance: an evolving challenge

PURPOSE OF REVIEW

Antimicrobial resistance is an increasing threat to patients also in nosocomial central nervous system (CNS) infections. The present review focusses on optimizing intravenous treatment in order to achieve sufficient concentrations of antibiotics in the different compartments of the CNS when the causative pathogens have reduced sensitivity to antibiotics or/and the impairment of the blood-cerebrospinal fluid (CSF) and blood-brain barrier is mild.

RECENT FINDINGS

Experience has been gathered with treatment protocols for several established antibiotics using increased doses or continuous instead of intermittent intravenous therapy. Continuous infusion in general does not increase the average CSF concentrations (or the area under the concentration-time curve in CSF) compared to equal daily doses administered by short-term infusion. In some cases, it is postulated that it can reduce toxicity caused by high peak plasma concentrations. In case reports, new β-lactam/β-lactamase inhibitor combinations were shown to be effective treatments of CNS infections.

SUMMARY

Several antibiotics with a low to moderate toxicity (in particular, β-lactam antibiotics, fosfomycin, trimethoprim-sulfamethoxazole, rifampicin, vancomycin) can be administered at increased doses compared to traditional dosing with low or tolerable adverse effects. Intrathecal administration of antibiotics is only indicated, when multiresistant pathogens cannot be eliminated by systemic therapy. Intravenous should always accompany intrathecal treatment.