First reported case of intraventricular tigecycline for meningitis from extremely drug-resistant Acinetobacter baumannii

Clinical Experience with Off-Label Intrathecal Administration of Selected Antibiotics in Adults: An Overview with Pharmacometric Considerations

Drain-associated intracerebral infections are life-threatening emergencies. Their treatment is challenging due to the limited penetration of antibiotics to the site of infection, resulting in potentially inadequate exposure. The emergence of multidrug-resistant pathogens might force the use of off-label intrathecal (IT) doses of antibiotics. We reviewed the literature on general aspects determining intrathecal dosing regimen, using pharmacometric knowledge. We summarised clinical experience with IT doses of antibiotics that are usually not used intrathecally, as well as the outcome of the cases and concentrations reached in the cerebrospinal fluid (CSF). Factors determining the IT regimen are the size of the ventricle system and the CSF drainage volume. With regard to pharmacometrics, pharmacokinetic/pharmacodynamic indices are likely similar to those in non-cerebral infections. The following number (N) of cases were described: benzylpenicillin (>50), ampicillin (1), ceftazidime (2), cephaloridine (56), ceftriaxone (1), cefotiam (1), meropenem (57), linezolid (1), tigecycline (15), rifampicin (3), levofloxacin (2), chloramphenicol (3) and daptomycin (8). Many side effects were reported for benzylpenicillin in the 1940-50s, but for the other antibiotics, when administered correctly, all side effects were minor and reversible. These data might help when choosing an IT dosing regimen in case there is no alternative option due to antimicrobial resistance.

Risk factors and cerebrospinal fluid indexes analysis of intracranial infection by Acinetobacter baumannii after neurosurgery

Background

Intracranial infection by Acinetobacter baumannii (A. baumannii) after neurosurgery has always been a difficult problem for neurosurgeons. This study analyzed risk factors that discriminated A. baumannii from other bacteria causing intracranial infection after neurosurgery. It also examined the differences in the cerebrospinal fluid (CSF) indexes to explore their value in the early diagnosis of intracranial infection by A. baumannii.

Methods

We retrospectively reviewed ten years (January 2011 to May 2021) of postoperative central nervous system (CNS) infections in the First Hospital of China Medical University. According to the pathogen, CNS infections were divided into A. baumannii group and other species of bacteria group. We collected clinical and laboratory information of patients, and statistical analysis was performed with SPSS 26.0. Risk factors were screened by univariate analysis, and independent risk factors were screened by multiple logistic regression analysis. Finally, CSF-Pro, CSF-Glu, CSF-Cl, CSF-monocytes (%), CSF-multinucleated cells (%) levels, and CSF multinucleated cells%/monocytes% in the different groups were analyzed.

Results

A total of 155 patients were included, 62 cases (40%) of intracranial infection by A. baumannii and 93 cases (60%) by other species of bacteria. The analysis showed that indwelling nasogastric tubes (P＜0.001, OR = 4.231), indwelling peripherally inserted central catheters (PICCs) (P = 0.041, OR = 2.765), and CSF drainage obstruction (P = 0.003, OR = 3.765) were independent risk factors for intracranial infection by A. baumannii after neurosurgery. Indwelling ventriculoperitoneal shunt (VPS) was a protective factor (P = 0.033, OR = 0.22). In addition, compared with other bacterial groups, the A. baumannii group had higher CSF-pro and CSF- multinucleated cells (%) levels and lower CSF-Glu and CSF- monocytes (%) levels, and the difference was statistically significant (P < 0.01).

Conclusions

Our results elucidate risk factors and differences in CSF indexes for intracranial infection by A. baumannii after neurosurgery that could be detected and prevented early to reduce mortality.

Intrathecal tigecycline is a safe and effective treatment for central nervous system infections

Both the safety and effectiveness of intrathecal tigecycline (TGC) for treatment of infections of the central nervous system (CNS) are discussed using the clinical findings from a study of a recent patient who came to our attention, along with a literature review. Although penetration into the CNS is low (approximately 11%), intraventricular TGC could help treat patients with severe post- neurosurgical CNS infections. The use of multiple routes of TGC administration appears to be encouraging and should be considered in managing life-threatening intraventricular infections.

Intracranial Myroides odoratimimus Infection After EVD Successfully Treated with Intravenous Plus Intraventricular Tigecycline: A Case Report

Intracranial infections are the most serious and common postoperative complications with significant mortality and morbidity. Myroides odoratimimus (M. odoratimimus), a Gram-negative environmental species and an opportunistic microorganism, predominantly infects immunocompromised individuals. Limited clinical experiences and documented multidrug resistance have resulted in a scarcity of data on the treatment of M. odoratimimus infections. As far as we know, this is the first reported case of an intracranial M. odoratimimus infection with external ventricular drains (EVD) that was effectively treated with a combination of intravenous and intraventricular tigecycline in an immunocompetent adult host.

The Blood-Brain Barrier and Pharmacokinetic/Pharmacodynamic Optimization of Antibiotics for the Treatment of Central Nervous System Infections in Adults

Bacterial central nervous system (CNS) infections are serious and carry significant morbidity and mortality. They encompass many syndromes, the most common being meningitis, which may occur spontaneously or as a consequence of neurosurgical procedures. Many classes of antimicrobials are in clinical use for therapy of CNS infections, some with established roles and indications, others with experimental reporting based on case studies or small series. This review delves into the specifics of the commonly utilized antibacterial agents, updating their therapeutic use in CNS infections from the pharmacokinetic and pharmacodynamic perspectives, with a focus on the optimization of dosing and route of administration that have been described to achieve good clinical outcomes. We also provide a concise synopsis regarding the most focused, clinically relevant information as pertains to each class and subclass of antimicrobial therapeutics. CNS infection morbidity and mortality remain high, and aggressive management is critical in ensuring favorable patient outcomes while averting toxicity and upholding patient safety.

Intrathecal or Intraventricular Tigecycline Therapy for Central Nervous System Infection Associated with Carbapenem-Resistant Klebsiella pneumoniae

PURPOSE

Infection with carbapenem-resistant Klebsiella pneumoniae (CRKP) is a great challenge. Central nervous system (CNS) infection caused by CRKP is rarely reported, and effective treatment is limited. Thus, this study aimed to assess intrathecal (IT) or intraventricular (IVT) injection of tigecycline for clearing infection with CRKP in CNS.

PATIENTS AND METHODS

Two patients who had intracranial infection with CRKP after craniotomy were treated in our institution and analyzed retrospectively, summarizing their therapeutic schedules.

RESULTS

They all had a fever with the positive results of cerebrospinal fluid (CSF) test, and CSF culture showed positive for CPKP, which was sensitive only to tigecycline. In addition, the MIC of polymyxin B was not tested due to the limited laboratory conditions. After IT or IVT injection of tigecycline treatment, the temperature of the patients became normal in 3 days, with normal levels of white blood cells, protein, glucose and chlorine concentrations in the CSF. Crucially, twice CSF cultures also became negative with no clinical symptoms of intracranial infection after IT or IVT injection of tigecycline treatment. Moreover, there were no adverse drug reactions observed.

CONCLUSION

IT or IVT injection of tigecycline may be a bright choice to control intracranial infection with CRKP.

The Pharmacokinetics/Pharmacodynamics and Neurotoxicity of Tigecycline Intraventricular Injection for the Treatment of Extensively Drug-Resistant Acinetobacter baumannii Intracranial Infection

Objective

This study aimed to provide feasible suggestions for intraventricular injection of tigecycline to treat intractable Acinetobacter baumannii intracranial infections by studying its pharmacokinetics/pharmacodynamics and neurotoxicity.

Methods

A simple and reliable two-dimensional high-performance liquid chromatography (2D-HPLC) method was used to determine tigecycline concentration. The pharmacokinetics (PK) of tigecycline in cerebrospinal fluid (CSF) was investigated by performing therapeutic drug monitoring (TDM). The pharmacodynamics (PD) of tigecycline was evaluated by its minimum inhibitory concentration (MIC) against XDR A. baumannii. CCK8 assay was used to evaluate the cytotoxicity of different concentrations of tigecycline effect on PC12 cells, and apoptosis assay was analyzed by flow cytometry.

Results

Tigecycline retention time in 2D-HPLC was 7.636 min. The lower limit of quantitation (LLOQ) was 0.1mg/L, which met the requirements of concentration determination for TDM. The MIC₅₀ and MIC₉₀ values of tigecycline for A. baumannii were 2 and 4 mg/L, respectively. After a dose of 5mg tigecycline, Cmax in CSF was 37.894 mg/L which was high above the MIC values. The t _1/2 of tigecycline was estimated to be 2.73 hours. Tigecycline significantly decreased cell viability as assessed and induced apoptosis of the PC12 cell. The IC₅₀ value of PC12 cells treated with tigecycline was about 51.35 mg/L.

Conclusion

Intraventricular injection of tigecycline is a promising method for treating XDR A. baumannii intracranial infection. Since a high concentration of tigecycline in CSF may have potential neurotoxicity, and the t _1/2 was short, giving small doses of less than 5 mg at least twice a day may be safer and more effective. Intraventricular injection of tigecycline must be selected cautiously and best carried out under TDM.

Autologous Free Fascia Lata Can Be Used as Dura Graft in the Salvage Treatment of Recalcitrant Postcraniotomy Intracranial Infection Caused by Multidrug-Resistant Gram-Negative Bacteria

Objective

The multidrug-resistant (MDR) gram-negative bacteria-induced intracranial infections after neurosurgical procedures represent a particular therapeutic challenge. Combining the removal of infected prosthetic meninge plus an appropriate antibiotic administration appears to be the only therapeutic strategy likely to succeed when the infection is complicated by artificial dura mater. This study aimed to assess the efficacy of free fascia lata as a substitute for dura reconstruction in the salvage treatment for such recalcitrant nosocomial infections.

Methods

The retrospective, observational study was conducted at Shanghai Tenth hospital. Patients with definite intracranial infection caused by MDR Gram-Negative bacteria who underwent salvage dura reconstruction using autologous free fascia lata were included in the study. Electronic medical data on clinical characteristics, underlying condition, bacterial culture, antibiotic susceptibilities, perioperative management, surgical techniques, outcome, and follow-up were collected and analyzed.

Results

19 patients were included in the study cohort. All these patients underwent salvage surgery, including removal of infected artificial dura substitute, achievement of complete dura seal with free fascia lata, and other adjunctive procedures to drain the CSF and infuse sensitive antimicrobial agents. Intraventricular or intrathecal administration of antibiotics, including Colistin (14 case), Tigecycline (1 case), Amikacin (1 case), was employed in 16 patients. The infection was cured in 17 patients. In-hospital death occurred in 3 patients. One died from multiple system/organ failure, 1 died from massive occipital ICH, 1 died from brain stem hemorrhage after ventricular-peritoneal shunt surgery. The patients remained without clinical evidence of recurrence during the follow-up period.

Conclusion

On the basis of a comprehensive approach to achieving prompt sterilization of causative pathogens and an optimal healing environment, free fascia lata can serve as a simpler but effective option for dura reconstruction even in the setting of a severe septic area for patients who otherwise need much more complicated and demanding tissue transfer surgery.

Two Cases Report of Intrathecal Tigecycline Therapy for Intracranial Infection with Acinetobacter baumannii and Review of Literatures

OBJECTIVE

To explore the treatment scheme for intracranial infection with Acinetobacter baumannii.

METHODS

We retrospective analyzed two cases of patients of intracranial infection with Acinetobacter baumannii.

RESULTS

The intracranial infection was controlled effectively by the scheme to intravenous"tigecycline + cefperazone-sulbactam"combined with intrathecal tigecycline injection, the two patients recover well with 21 months' follow-up.

CONCLUSIONS

Tigecycline-based drug scheme combined with intrathecal tigecycline injection can achieve the effect of controlling intracranial infection. Lumbar cisterna drainage tube plays a major role in controlling intracranial infection.

Successful Treatment of Postneurosurgical Ventriculitis Caused by Extensively Drug-resistant Acinetobacter baumannii in a Child: Case Report

Introduction: The incidence of postneurosurgical Acinetobacter baumannii ventriculitis/meningitis, primarily due to drug-resistant strains, has increased considerably in recent years. However, limited therapeutic options are available because most antibiotics poorly penetrate the blood-brain barrier, especially in pediatric patients. Case Presentation: A five-year-old boy developed ventriculitis due to extensively drug-resistant A. baumannii (XDRAB) after bilateral frontal external ventricular drainage for spontaneous intraventricular hemorrhage. The boy was safely and successfully treated with intraventricular (IVT)/intrathecal (ITH) polymyxin B together with intravenous tigecycline plus cefoperazone/sulbactam. Conclusions: In the present case, postneurosurgical XDRAB ventriculitis was closely associated with intraventricular hemorrhage and the placement of external ventricular drainage. IVT/ITH polymyxin B combined with intravenous tigecycline and cefoperazone sulbactam could be a therapeutic option against XDRAB ventriculitis in children.

Does Tigecycline Have a Place in Therapy for Rickettsial Infection of the Central Nervous System?

This brief report documents the safety and efficacy of high-dose tigecycline as a salvage-therapy in in a case series of five patients with serious central nervous system (CNS) rocky mountain spotted fever (RMSF). These severily ill patients were unable to take any oral drug therapy, parenteral doxycycline was unavailable and absorption of oral doxycycline was a concern in these critically ill patients. As far as we know, we report the successfull use of tigecycline for the treatment of rickettsial meningitis for the first time in Italy. We suggest more studies on tigecycline in severe CNS infections from Rickettsia species and multi-drug resistant bacteria, especially the use of tigecycline at higher than standard doses in these life-threathening infectious diseases.

Dose optimisation of antibiotics used for meningitis

PURPOSE OF REVIEW

Central nervous system (CNS) infections such as ventriculitis and meningitis are associated with significant morbidity and mortality. In part, this may be due to increased difficulties in achieving a therapeutic antibiotic concentration at the site of infection due to both the pharmacokinetic (PK) changes observed during critical illness and the reduced antibiotic penetration through the blood brain barrier. This paper reviews the pharmacodynamics (PD) and CNS PKs of antibiotics used for Gram-negative bacterial CNS infections to provide clinicians with practical dosing advice.

RECENT FINDINGS

Recent PK studies have shown that currently used intravenous antibiotic dosing regimens may not achieve a therapeutic exposure within the CNS, even for reportedly 'susceptible' bacteria per the current clinical meningitis breakpoints. Limited data exist for new β-lactam antibiotic/β-lactamase inhibitor combinations, which may be required for multidrug resistant infections. Intraventricular antibiotic administration, although not a new concept, has further evidence demonstrating improved patient outcomes compared with intravenous therapy alone, despite the ongoing paucity of PK studies guiding dosing recommendations.

SUMMARY

Clinicians should obtain the bacterial minimum inhibitory concentration when treating patients with CNS Gram-negative bacterial infections and consider the underlying PK/PD principles when prescribing antibiotics. Therapeutic drug monitoring, where available, should be considered to guide dosing. Intraventricular therapy should also be considered for patients with ventricular drains to optimise clinical outcomes.

Successful Treatment of Ventriculitis Caused by MDR/XDR Gram-Negative Bacillus Using Ceftazidime/Avibactam: Case Series and Literature Review

Background

Central nervous system (CNS) infections caused by multidrug-resistant (MDR) and extensively drug-resistant (XDR) Gram-negative bacillus, including carbapenem-resistant Enterobacteriaceae (CRE) and Pseudomonas aeruginosa, are associated with high mortality rates. Clinical trials of ceftazidime/avibactam (CAZ/AVI) on infections of other systems indicate that they are effective against these infections. However, clinical studies on the efficacies of CAZ/AVI in the treatment of CNS infections have not been done.

Case Presentation

We evaluated 3 patients diagnosed with MDR/XDR Gram-negative bacillus-associated CNS infections, and effectively treated with CAZ/AVI. Moreover, we performed literature reviews. Before the onset of CNS infections, the 3 patients were subjected to neurosurgical operations, treated with mechanical ventilation, long-term intensive care unit therapy, and various antibiotics. By intravenously administering CAZ/AVI, combined with another antibiotic, the MDR/XDR K. pneumoniae and P. aeruginosa associated ventriculitis was effectively treated in the 3 patients.

Conclusion

CAZ/AVI is a viable treatment option for CNS infections caused by MDR/XDR Gram-negative bacteria.

Dose optimisation based on pharmacokinetic/pharmacodynamic target of tigecycline

Tigecycline, a new first-in-class glycylcycline antibiotic, has shown promising efficacy against a broad range of micro-organisms. It is widely prescribed for various infections, with most prescriptions being considered for off-label use. However, only a few years after its approval by the US Food and Drug Administration (FDA), tigecycline is suspected of increasing all-cause mortality. Some clinicians have suggested such unfavourable outcomes correlate with inadequate drug exposure at the infection site. The pharmacokinetic/pharmacodynamic (PK/PD) profile of a drug plays an important role in predicting its antibiotic effect, which for tigecycline is determined as the ratio of area under the concentration-time curve (AUC) to minimum inhibitory concentration (MIC). In this study, PK/PD targets based on infection sites, bacterial isolates and patient populations are discussed. Generally, a higher dosage of tigecycline for the treatment of serious infections has been recommended in previous reports. However, the latest finding of tigecycline's atypical protein binding property requires consideration when recommending further use. In addition, combination therapy with other antibiotics provides another option by potentially lowering the MICs of multidrug-resistant bacteria.

Successful treatment of pyogenic ventriculitis caused by extensively drug-resistant Acinetobacter baumannii with multi-route tigecycline: A case report

BACKGROUND

Pyogenic ventriculitis caused by extensively drug-resistant Acinetobacter baumannii (A. baumannii) is one of the most severe complications associated with craniotomy. However, limited therapeutic options exist for the treatment of A. baumannii ventriculitis due to the poor penetration rate of most antibiotics through the blood-brain barrier.

CASE SUMMARY

A 68-year-old male patient with severe traumatic brain injury developed pyogenic ventriculitis on postoperative day 24 caused by extensively drug-resistant A. baumannii susceptible to tigecycline only. Successful treatment was accomplished through multi-route administration of tigecycline, including intravenous combined with continuous ventricular irrigation plus intraventricular administration. The pus was cleared on the 3^rd day post-irrigation, and cerebrospinal fluid cultures were negative after 12 d.

CONCLUSION

Our findings suggest that multi-route administration of tigecycline can be a therapeutic option against pyogenic ventriculitis caused by extensively drug-resistant A. baumannii.

Successful Treatment With Intrathecal and Intravenous Polymyxin B-Based Combination Against MDR Acinetobacter baumannii Meningitis in Pediatric Patient: A Case Report

Background: Nosocomial meningitis with multidrug-resistant (MDR) or extensively drug-resistant (XDR) Acinetobacter baumannii is a life-threatening complication in neurosurgery. Treatment of these infections is challenging because of poor penetration of the available antibiotics into the cerebrospinal fluid (CSF). Intrathecal (ITH) or intraventricular (IVT) administration of antibiotics is increasingly used as the last treatment option against MDR/XDR Gram-negative bacteria meningitis not responding to intravenous (IV) regimens. However, pertinent data in pediatric patients is scarce. Case Presentation: A 14-year-old male patient developed meningitis from an MDR strain of A. baumannii following endoscopic endonasal resection of craniopharyngioma. Despite a combination therapy involving IV tigecycline, we observed clinical and bacteriologic failure. The patient was then successfully treated with an ITH and IV polymyxin B-based combination. Quantification of tigecycline and polymyxin B in CSF was performed with two-dimensional high-performance liquid chromatography (2D-HPLC) and HDLC coupled with tandem mass spectrometry (HPLC-MS/MS), respectively. Adverse drug reactions (neurotoxicity and skin hyperpigmentation), probably induced by polymyxin B, were acceptable and reversible. Conclusions: The case illustrates ITH and IV Polymyxin B-based combination is an optimal therapeutic option against MDR A. baumannii meningitis in this pediatric patient. In the future, real-time PK/PD data obtained from patients during ITH/IVT polymyxin B therapy should be required to optimize polymyxin use with maximal efficacy and minimal adverse effects.

Outcome following postneurosurgical Acinetobacter meningitis: an institutional experience of 72 cases

OBJECTIVE

The authors aimed to evaluate the antimicrobial susceptibility pattern of Acinetobacter isolates responsible for nosocomial meningitis/ventriculitis in the neurosurgical ICU. The authors also sought to identify the risk factors for mortality following Acinetobacter meningitis/ventriculitis.

METHODS

This was a retrospective study of 72 patients admitted to the neurosurgical ICU between January 2014 and December 2018 with clinical and microbiological diagnosis of nosocomial postneurosurgical Acinetobacter baumanii meningitis/ventriculitis. Electronic medical data on clinical characteristics, underlying pathology, CSF cytology, antibiotic susceptibilities, and mortality were recorded. To evaluate the outcome following nosocomial postneurosurgical Acinetobacter meningitis/ventriculitis, patients were followed up until discharge or death in the hospital. Kaplan-Meier survival analysis and multivariable Cox proportional hazards models were used to compute factors affecting survival.

RESULTS

The study population was divided into two groups depending on the final outcome of whether the patient died or survived. Forty-three patients (59.7%) were included in the survivor group and 29 patients (40.3%) were included in the nonsurvivor group. Total in-hospital mortality due to Acinetobacter meningitis/ventriculitis was 40.3% (29 cases), with a 14-day mortality of 15.3% and a 30-day mortality of 25%. The 43 (59.7%) patients who survived had a mean length of hospital stay of 44 ± 4 days with a median Glasgow Outcome Scale-Extended score at discharge of 6. On univariate analysis, age > 40 years (p = 0.078), admission Glasgow Coma Scale (GCS) score ≤ 8 (p = 0.003), presence of septic shock (p = 0.011), presence of external ventricular drain (EVD) (p = 0.03), CSF white blood cell (WBC) count > 200 cells/mm3 (p = 0.084), and comorbidities (diabetes, p = 0.036; hypertension, p = 0.01) were associated with poor outcome. Carbapenem resistance was not a risk factor for mortality. According to a multivariable Cox proportional hazards model, age cutoff of 40 years (p = 0.016, HR 3.21), GCS score cutoff of 8 (p = 0.006, HR 0.29), CSF WBC count > 200 cells/mm3 (p = 0.01, HR 2.76), presence of EVD (p = 0.001, HR 5.42), and comorbidities (p = 0.017, HR 2.8) were found to be significant risk factors for mortality.

CONCLUSIONS

This study is the largest case series reported to date of postneurosurgical Acinetobacter meningitis/ventriculitis. In-hospital mortality due to Acinetobacter meningitis/ventriculitis was high. Age older than 40 years, GCS score less than 8, presence of EVD, raised CSF WBC count, and presence of comorbidities were risk factors for mortality.

Intraventricular Tigecycline as a Last Resort Therapy in a Patient with Difficult-to-Treat Healthcare-Associated Acinetobacter baumannii Ventriculitis: a Case Report

Healthcare-associated ventriculitis and meningitis is a common complication in patients who suffer from head trauma or have undergone a neurosurgery. Healthcare-associated ventriculitis and meningitis is associated with significant morbidity and mortality. Complications of healthcare-associated ventriculitis and meningitis include persistent vegetative state, moderate and severe disability, and death. Acinetobacter baumannii is the causative pathogen in 3.6–11.2% of cases of healthcare-associated ventriculitis and meningitis. Cases of difficult-to-treat healthcare-associated A. baumannii ventriculitis and meningitis are being reported more frequently. However, in most of these cases, a combination of intravenous (IV) and intraventricular (IVT)/intrathecal colistin achieves good therapeutic outcome. This report describes a clinical case of difficult-to-treat healthcare-associated A. baumannii ventriculitis. The A. baumannii strain was sensitive to colistin and trimethoprim-sulfamethoxazole, intermediate to tigecycline, and resistant to other antibiotics. While colistin was the drug of choice in our case, the patient developed anaphylactoid reaction during the IV administration of the loading dose of colistin, which mandated us to discontinue colistin and complicated the treatment of our patient. The patient did not respond to a combination of IV antibiotics that included meropenem, trimethoprim-sulfamethoxazole, and tigecycline. However, when IVT tigecycline was added as a last-resort therapeutic option, the patient’s ventriculitis dramatically improved, and the patient was discharged from the hospital. Physicians who treat patients with healthcare-associated A. baumannii ventriculitis might resort to IVT tigecycline when they run out of therapeutic options.

Sequential intraventricular injection of tigecycline and polymyxin B in the treatment of intracranial Acinetobacter baumannii infection after trauma: a case report and review of the literature

BACKGROUND

Intracranial infection after craniotomy is one of the most serious postoperative complications, especially multidrug-resistant (MDR) or extensively drug-resistant (XDR) bacterial meningitis, and strongly affects the prognosis of patients. Current treatment experience regarding these infections is scarce.

CASE PRESENTATION

We report a case of severe intracranial infection of XDR Acinetobacter baumannii (A. baumannii) that was treated by intravenous (IV) injection, sequential intraventricular (IVT) injection of tigecycline and polymyxin B, and other anti-infective drugs. Good results were obtained, and the patient was eventually discharged from the hospital. This case is characterized by intracranial infection.

CONCLUSIONS

The polymyxin B IV + IVT pathway is an ideal treatment strategy for XDR A. baumannii. The tigecycline IVT pathway is also a safe treatment option.

Intrathecal Antibacterial and Antifungal Therapies

Intrathecal administration of anti-infectives is indicated in central nervous system infections by multiresistant pathogens when drugs that can reach adequate cerebrospinal fluid (CSF) concentrations by systemic therapy are not available. Antibiotics that readily pass the blood-brain and blood-CSF barriers and/or that have low toxicity allowing an increase in the daily dosage should not be used for intrathecal therapy. Intrathecal therapy is accompanied by systemic treatment. Antibacterials indispensable for intrathecal therapy include aminoglycosides, colistin, daptomycin, tigecycline, and vancomycin. Limited experience suggests the utility of the antifungals amphotericin B and caspofungin. Intraventricular administration ensures distribution throughout the CSF compartment, whereas intralumbar dosing often fails to attain adequate antibiotic concentrations in the ventricles. The individual dose is determined by the estimated size of the CSF space and by the estimated clearance from CSF. For moderately lipophilic anti-infectives with a molecular weight above approximately 1,000 g/mol, as well as for hydrophilic drugs with a molecular weight above approximately 400 g/mol, one daily dose is normally adequate. The ventricular drain should be clamped for 15 to 120 min to facilitate the distribution of the anti-infective in the CSF space. Therapeutic drug monitoring of the trough levels is necessary only in cases of therapeutic failure.

Uso compasional de tigeciclina intraventricular en pacientes con ventriculitis causada por Enterococcus faecium. Reporte de seis casos pediátricos

Introducción: La Tigeciclina es un fármaco de uso restringido en pediatría. El uso de este antibiótico por vía intraventricular es una decisión de uso compasivo en casos de bacterias altamente resistentes, y para los casos en que no exista otra alternativa. Caso clínico: Se presenta seis casos de pacientes con diagnóstico de ventriculitis a Enterococcus faecium que recibieron tigeciclina intraventricular con evolución bacteriológica exitosa. Se discute las dosis utilizadas por vía endovenosa e intraventricular. Conclusiones: el uso de este antibiótico por vía intraventricular puede ser una alternativa exitosa en casos de gérmenes altamente resistentes y cuando no exista otra alternativa terapéutica.

Successful Treatment of Serious Meningitis Caused by Extremely Carbapenem-Resistant Enterobacter cloacae (MIC≥16mg/L) with i.v. Meropenem and i.v. Amikacin Plus Intraventricular Amikacin

Background

Carbapenem-resistant Enterobacteriaceae (CRE) meningitis are associated with poor outcomes and high mortality. Here, we report the first successful treatment case of serious meningitis caused by extremely carbapenem-resistant Enterobacter cloacae (minimum inhibitory concentration (MIC) of imipenem ≥16mg/L) with high-dose prolonged infusion of meropenem and i.v. amikacin plus intraventricular (IVT) amikacin.

Case presentation

A 17-year-old girl developed meningitis from an extremely carbapenem-resistant Enterobacter cloacae (MIC of imipenem ≥16mg/L) as a complication of the removal of a giant central neurocytoma located in bilateral and third ventricles. The patient received four surgeries (one tumor excision and three external ventricular drainages) and was treated with a 70 days course of antibiotics therapy during 100 days hospitalization. Finally, she was safely and successfully treated with the high-dose prolonged infusion of meropenem and i.v. amikacin plus IVT amikacin.

Conclusion

This case report shows the possibility of the antibiotic regimen of high-dose prolonged infusion of meropenem and i.v. amikacin plus IVT amikacin in the successful treatment of CRE meningitis (MIC of imipenem ≥16mg/L) especially when other antibiotics are unavailable or restricted.

Antibiotic Distribution into Cerebrospinal Fluid: Can Dosing Safely Account for Drug and Disease Factors in the Treatment of Ventriculostomy-Associated Infections?

Ventriculostomy-associated infections, or ventriculitis, in critically ill patients are associated with considerable morbidity. Efficacious antibiotic dosing for the treatment of these infections may be complicated by altered antibiotic concentrations in the cerebrospinal fluid due to variable meningeal inflammation and antibiotic properties. Therefore, doses used to treat infections with a higher degree of meningeal inflammation (such as meningitis) may often fail to achieve equivalent exposures in patients with ventriculostomy-associated infections such as ventriculitis. This paper aims to review the disease burden, infection rates, and common pathogens associated with ventriculostomy-associated infections. This review also seeks to describe the disease- and drug-related factors that influence antibiotic distribution into cerebrospinal fluid and provide a critical appraisal of current dosing of antibiotics commonly used to treat these types of infections. A Medline search of relevant articles was conducted and used to support a review of cerebrospinal fluid penetration of vancomycin, including critical appraisal of the recent paper by Beach et al. recently published in this journal. We found that in the intensive care unit, ventriculostomy-associated infections are the most common and serious complication of external ventricular drain insertion and often result in prolonged patient stay and increased healthcare costs. Reported infection rates are extremely variable (between 0 and 45%), hindered by the inherent diagnostic difficulty. Both Gram-positive and Gram-negative organisms are associated with such infections and the rise of multi-drug-resistant pathogens means that effective treatment is an ongoing challenge. Disease factors that may need to be considered are reduced meningeal inflammation and the presence of critical illness; drug factors include physiochemical properties, degree of plasma-protein binding, and affinity to active transporter proteins present in the blood-cerebrospinal fluid barrier. The relationship between cerebrospinal fluid antibiotic exposures in the setting of ventriculostomy-associated infection and clinical response has not been fully elucidated for many of the antibiotics commonly used in its treatment. More thorough and clinically relevant investigations are needed to better define blood pharmacokinetic/pharmacodynamics targets and optimal therapeutic exposures for treatment of ventriculostomy-associated infections. It is hoped that this future research will be able to provide clearer recommendations for clinicians frequently faced with dosing-related dilemmas when treating patients with these challenging infections.

A case report of intraventricular and intrathecal tigecycline infusions for an extensively drug-resistant intracranial Acinetobacter baumannii infection

RATIONALE

The treatment of intracranial Acinetobacter baumannii infections is made difficult by multidrug-resistance poor drug penetration through the blood-brain barrier (BBB). Although tigecycline appears to be effective against A baumannii, it is only administered intravenously because it does not readily cross the BBB. The addition of intraventricular (IVT) or intrathecal infusions of tigecycline could revolutionize clinical therapy for intracranial A baumannii infections. However, there are few reports on the successful use of such treatments.

PATIENT CONCERNS

We report the case of a 17-year-old male who presented with high fever and neck rigidity after intracranial drainage.

DIAGNOSIS

Intracranial infection with extensively drug-resistant A baumannii after intracranial drainage.

INTERVENTIONS

On the advice of a clinical pharmacist, the patient was administered intrathecal infusions of tigecycline after treatment failure with IVT tigecycline.

OUTCOMES

The patient's body temperature returned to normal. Thereafter, the patient was in good clinical condition without signs of cerebrospinal fluid infection and tuberculosis.

LESSONS

However, when central nervous system infections fail IVT tigecycline, clinicians should consider changing to intrathecal tigecycline infusions rather than raising the dose of IVT tigecycline. In addition, the co-administration of tigecycline with other drugs that can penetrate the BBB should not be ruled out.

Intraventricular tigecycline for the treatment of shunt infection: a case in pediatrics

Ventriculoperitoneal (VP) shunt infections are seen in 3%-17% of patients with VP shunts. These infections may cause severe morbidity and mortality. Staphylococci are the most common cause of CSF shunt-associated infections, although gram-negative bacteria (especially multidrug-resistant [MDR] and extensive drug-resistant [XDR] bacteria) also play an important role. Due to increased antibiotic resistance, sometimes off-label usage of antibiotics is considered. Tigecycline is one of these antibiotics. It should not be used unless there are no other antibiotic treatment options available, especially in children. It belongs to the glycylcycline class of antibiotic agents and inhibits protein translation in bacteria by binding to the 30S ribosomal subunit. The authors describe the case of a patient who had an XDR Klebsiella pneumoniae-positive VP shunt infection. After removal of his VP shunt, an external ventricular drain was inserted, and the patient was treated with a combination of intravenous (1.2 mg/kg/day) and intraventricular (4 mg/day) tigecycline in addition to his meropenem (120 mg/kg/day) treatment. On the 7th day of the combined therapy, his CSF culture was sterile. Because tigecycline distribution into the tissues is not sufficient with intravenous administration, combining it with intraventricular infusion can provide new treatment methods. However, further studies are needed for its use as a treatment method in children.

Emergence and Persistence of High-Risk Clones Among MDR and XDR A. baumannii at a Brazilian Teaching Hospital

Dissemination of carbapenem-resistant Acinetobacter baumannii is currently one of the priority themes discussed around the world, including in Brazil, where this pathogen is considered endemic. A total of 107 carbapenem-resistant A. baumannii (CRAB) isolates were collected from patients with bacteraemia attended at a teaching hospital in Brazil from 2008 to 2014. From these samples, 104 (97.2%) carried bla_{OXA−23−like}, all of them associated with ISAba1 The bla_OXA−231 (1.9%) and bla_OXA−72 (0.9%) genes were also detected in low frequencies. All isolates were susceptible to minocycline, and 38.3% of isolates presented intermediate susceptibility to tigecycline (MIC = 4 μg/ml). Molecular typing assessed by multi-locus sequence typing demonstrated that the strains were mainly associated with clonal complexes CC79 (47.4%), followed by CC1 (16.9%), and CC317 (18.6%), belonging to different pulsotypes and in different prevalences over the years. Changes in the clones' prevalence reinforce the need of identifying and controlling CRAB in hospital settings to preserve the already scarce therapeutic options available.

Multidrug Resistant Brain Abscess Due to Acinetobacter baumannii Ventriculitis Cleared by Intraventricular and Intravenous Tigecycline Therapy: A Case Report and Review of Literature

Objective: Ventricular infection from multidrug-resistant (MDR) Acinetobacter baumannii (A. baumannii) is one of the most severe complications of craniotomy. However, the availability of effective therapeutic options for these infections is limited. Thus, this report aims to describe the efficacy of abscess clearance by intraventricular and intravenous tigecycline therapy in managing patients with multidrug-resistant A. baumannii ventriculitis after neurosurgery. Moreover, the current literature on the use of tigecycline therapy for these life-threatening infections is reviewed and summarized, and a treatment regimen based on the available data is proposed.

Methods: A patient with multidrug-resistant A. baumannii ventriculitis was admitted in our hospital and was provided with a detailed therapeutic schedule. Tigecycline treatments for multidrug-resistant A. baumannii ventriculitis that were reported in the literature were also reviewed and summarized.

Results: The patient in our hospital underwent abscess clearance on a ventriculoscope and was subsequently subjected to multi-route tigecycline therapy 14 days after the start of the continuous ventricular irrigation (CVI) tigecycline and 3 days after the intraventricular (IVT) tigecycline. The signs of ventriculitis disappeared, and the Acinetobacter cerebrospinal fluid (CSF) load steadily decreased until CSF sterilization. Literature review identified seven cases of ventricular infection from multidrug-resistant A. baumannii treated with tigecycline. In the eight cases, all patients were male adults (>18 years), with a mean age of 46.1 (range: 22–75) years. Meningitis/ventriculitis was secondary to neurosurgery procedures for the management of various central nervous system diseases in all cases. A good clinical outcome was achieved in all eight patients with multidrug-resistant A. baumannii meningitis/ventriculitis treated with CVI and/or IVT tigecycline, and any relevant complications were not observed.

Conclusions: CVI and IVT tigecycline and IVT colistin could be considered as the first-line therapy in patients with ventricular infections from MDR/extreme drug-resistant A. baumannii. However, more studies should be conducted to confirm our observation.

Tigecycline in the treatment of multidrug-resistant Acinetobacter baumannii meningitis: Results of the Ege study

OBJECTIVES

In this study we retrospectively reviewed A. baumannii meningitis cases treated with tigecycline including regimens and evaluated the efficacy of tigecycline in the therapy.

PATIENTS AND METHODS

Study was performed in seven tertiary-care educational hospitals from five cities of Turkey and one center from France. We extracted data and outcomes of all adult (aged >18) patients with culture proven A. baumannii meningitis treated with tigecycline including antibiotic therapy until April 2016.

RESULTS

A total of 23 patients (15 male and eight female) fulfilled our inclusion criteria. All Acinetobacter strains were carbapenem-resistant and susceptible to tigecycline. Six cases received tigecycline monotherapy while 17 received tigecycline including combination therapy (10 with colistin, 4 with netilmicin, 3 with amikacin, 4 with meropenem). Seven of 23 cases (30%) died during the tigecycline including therapy (1 in monotherapy, 4 in colistin, 2 in netilmicin, 1 amikacin, one case received tigecycline + netilmicin followed by tigecycline + colistin). Hence, overall end of treatment (EOT) success was 70%. However, since further 27% died due to additional nosocomial infections, overall clinical success (relieved symptoms at the EOT and one-month post-therapy survival without any relapse or reinfection) decreased to 43%.

CONCLUSION

We conclude that tigecycline may be an alternative in the salvage treatment of nosocomial multidrug-resistant Acinetobacter spp. meningitis. Acinetobacter spp. Meningitis.

Successful treatment of extensively drug-resistant Acinetobacter baumannii ventriculitis with polymyxin B and tigecycline- a case report

Background

Acinetobacter baumannii nosocomial ventriculitis/meningitis, especially those due to drug-resistant strains, has substantially increased over recent years. However, limited therapeutic options exist for the Acinetobacter baumannii ventriculitis/meningitis because of the poor penetration rate of most antibiotics through the blood-brain barrier.

Case presentation

A 57-year-old male patient developed ventriculitis from an extensively drug-resistant strain of Acinetobacter baumannii after the decompressive craniectomy for severe traumatic brain injury. The patient was successfully treated with intraventricular and intravenous polymyxin B together with intravenous tigecycline.

Conclusions

The case illustrates intraventricular polymyxin B can be a therapeutic option against extensively drug-resistant Acinetobacter baumannii ventriculitis.