Posts filed under ‘Infecciones del SNC’

REVISION – Difusión de los antibióticos en el sistema nervioso central

Revista Española de Quimioterapia Febrero 2018 V.31 N.1 P.1–12.

José María Cabrera-Maqueda,corresponding author1 Luna Fuentes Rumí,1 Gabriel Valero López,1 Ana Esther Baidez Guerrero,1 Estefanía García Molina,1 José Díaz Pérez,1 and Elisa García-Vázquez2

RESUMEN

Las infecciones del SNC causadas por patógenos mutiresistentes suponen un reto terapéutico. El paso de fluidos y de solutos al SNC está estrechamente regulado a través de la BHE.La penetración de cualquier fármaco, inclusive los ATB, en el LCR depende del tamaño molecular, la lipofilicidad, la unión a proteínas plasmáticas y su afinidad por transportadores de la BHE. La relación entre el área bajo la curva en el LCR y el suero AUCCSF (Area Bajo la Curva en LCR)/AUCS (Area Bajo la Curva en suero) de una sustancia es el parámetro más preciso para determinar su capacidad de difusión.

Linezolid, algunas quinolonas y metronidazol consiguen altas concentraciones en LCR y son útiles para tratar microorganismos sensibles. Algunos ATB cuya permeabilidad a través de la BHE es baja pueden ser administrados directamente en el ventrículo a la vez que se realiza infusión IV. El ATB ideal para tratar una infección del SNC es pequeño, no tiene alta tasa de unión a proteínas plasmáticas, es moderadamente lipofílico y no es un ligando de alta afinidad a bombas de expulsión de la BHE.

Conocer la farmacocinética de los ATB y su interacción con la BHE permitirá mejorar el tratamiento de los pacientes con infecciones del SNC. En este artículo se exponen las propiedades físico-químicas de los principales grupos de ATB para evaluar cuáles son más prometedores en el tratamiento de las infecciones del SNC y cómo usarlos en la práctica clínica habitual.

PDF

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6159365/pdf/revespquimioter-31-1.pdf

Advertisements

May 19, 2019 at 7:13 pm

Microscopic Examination and Broth Culture of Cerebrospinal Fluid in Diagnosis of Meningitis

Journal of Clinical Microbiology June 1998 V.36 N.6 P.1617-1620

Dunbar SA et al

We reviewed the results of microscopic Gram stain examination and routine culture for 2,635 cerebrospinal fluid (CSF) samples processed in an adult hospital microbiology laboratory during 55 months. There were 56 instances of bacterial or fungal meningitis (16 associated with central nervous system [CNS] shunt infection), four infections adjacent to the subarachnoid space, four cases of sepsis without meningitis, and an additional 220 CSF specimens with positive cultures in which the organism isolated was judged to be a contaminant. Because 121 of these contaminants were isolated in broth only, elimination of the broth culture would decrease unnecessary work. However, 25% of the meningitis associated with CNS shunts would have been missed by this practice. The most common cause of meningitis was Cryptococcus neoformans, followed by Streptococcus pneumoniaeand Neisseria meningitidis. In 48 of 56 (88%) of cases, examination of the Gram-stained specimen revealed the causative organism. If patients who had received effective antimicrobial therapy prior to lumbar puncture are excluded, the CSF Gram stain is 92% sensitive. Microscopic examination incorrectly suggested the presence of organisms in only 3 of 2,635 (0.1%) CSF examinations. Thus, microscopic examination of Gram-stained, concentrated CSF is highly sensitive and specific in early diagnosis of bacterial or fungal meningitis.

Bacterial meningitis is a life-threatening infection. Although patients typically present with fever, headache, stiff neck, and altered mental status, these symptoms may be subtle in elderly or immunocompromised persons (1, 6, 7,18). Early implementation of appropriate antimicrobial therapy requires prompt identification of the infecting pathogen. Although culture is considered to be the definitive diagnostic test, microscopic examination of a Gram-stained specimen of cerebrospinal fluid (CSF) may provide immediate information about the causative microorganism. Previous studies have suggested that the sensitivity of this technique ranges from 60 to 90% and the specificity approaches 100% (1, 5,6, 8, 12, 18). Scheld concludes that the overall sensitivity is only 75% (14). It is often unclear whether earlier studies have stratified patients based upon their having received prior antimicrobial therapy. Further, the role of semiquantitative assessment of leukocytes (WBC) by microscopic examination as an indicator of infection (8, 12) is uncertain. The value of using broth culture in various populations is also questionable (9, 10,17). In the present study, we reviewed the results of microscopic examination and routine culture of 2,635 CSF specimens to establish the predictive value of the cytocentrifuged Gram stain and the usefulness of broth culture in a veteran population.

FULL TEXT

https://jcm.asm.org/content/36/6/1617

PDF

https://jcm.asm.org/content/jcm/36/6/1617.full.pdf

April 2, 2019 at 6:15 pm

Predictive Value of Cerebrospinal Fluid (CSF) Lactate Level vs CSF-Blood Glucose Ratio for the Diagnosis of Bacterial Meningitis Following Neurosurgery

Clinical Infectious Diseases July 1999 V.29 N.1 P.69-74

Stephen L. Leib; Remy Boscacci; Othmar Gratzl; Werner Zimmerli

The value of cerebrospinal fluid (CSF) lactate level and CSF/blood glucose ratio for the identification of bacterial meningitis following neurosurgery was assessed in a retrospective study. During a 3-year period, 73 patients fulfilled the inclusion criteria and could be grouped by preset criteria in one of three categories: proven bacterial meningitis (n = 12), presumed bacterial meningitis (n = 14), and nonbacterial meningeal syndrome (n = 47). Of 73 patients analyzed, 45% were treated with antibiotics and 33% with steroids at the time of first lumbar puncture. CSF lactate values (cutoff, 4 mmol/L), in comparison with CSF/blood glucose ratios (cutoff, 0.4), were associated with higher sensitivity (0.88 vs. 0.77), specificity (0.98 vs. 0.87), and positive (0.96 vs. 0.77) and negative (0.94 vs. 0.87) predictive values. In conclusion, determination of the CSF lactate value is a quick, sensitive, and specific test to identify patients with bacterial meningitis after neurosurgery.

FULL TEXT

https://academic.oup.com/cid/article/29/1/69/323396

PDF (CLIC en PDF)

April 2, 2019 at 6:13 pm

Characterization of Chemical Meningitis after Neurological Surgery

Clinical Infectious Diseases January 2001 V.32 N.2 P.179-185

Pierre Forgacs; Carl A. Geyer; Stephen R. Freidberg

We reviewed the records of 70 consecutive adult patients with meningitis after a neurosurgical procedure, to determine the characteristics that might help to distinguish a sterile postoperative chemical meningitis from bacterial infection. The spinal fluid profiles in bacterial and chemical meningitis are similar. The exceptions are that a spinal fluid white blood cell count >7500/µL (7500 × 106/L) and a glucose level of <10 mg/dL were not found in any case of chemical meningitis. The clinical setting and clinical manifestations were distinct enough that no antibiotic was administered after lumbar puncture to 30 (43%) of the 70 patients with postoperative meningitis. Chemical meningitis was infrequent after surgery involving the spine and sinuses. Patients with chemical meningitis did not have purulent wound drainage or significant wound erythema or tenderness, coma, new focal neurological findings, or onset of a new seizure disorder. They rarely had temperatures >39.4°C or cerebrospinal fluid rhinorrhea or otorrhea.

FULL TEXT

https://academic.oup.com/cid/article/32/2/179/319157

PDF (CLIC en PDF)

April 2, 2019 at 6:10 pm

Meningitis postquirúrgica. Características diferenciales de la meningitis aséptica post-quirúrgica

Neurocirugía ABRIL 2009 V.20 N.2

Ramos-Martínez; T. de las Heras-Carballo; C. Fernández-Mateos*; L. de Reina*; T. Álvarez de Espejo-Montiel; N. Escamilla-Fernández; I. Sánchez-Romero** e I. Millán***

Servicios de Medicina Interna (Unidad de Infecciosas) Neurocirugía* y Microbiología**. Sección de Bioestadística***. Hospital Universitario Puerta de Hierro. Madrid.

Introducción

La meningitis postquirúrgica es una complicación infrecuente que se acompaña de un incremento de la estancia hospitalaria y de una elevada mortalidad. Algunos de estos casos no son debidos a una verdadera infección sino a una inflamación aséptica de las meninges denominada meningitis aséptica post-quirúrgica (MAPQ). La adecuada identificación de estos casos permitiría una mejor utilización de los fármacos antimicrobianos.

Material y métodos

Estudio retrospectivo de los pacientes con meningitis postquirúrgica en un hospital terciario durante 14 años comparando las características clínicas de los pacientes con meningitis bacteriana postquirúrgica (MBP) frente a las de pacientes con MAPQ

Resultados

Durante el período analizado se identificaron 35 pacientes (71%) con MBP y 14 pacientes (29%) con MAPQ. La edad media de los pacientes con MBP fue similar a la de los pacientes con MAPQ. Hubo predominio de varones en el grupo de MBP (71%) en relación con los pacientes con MAPQ (36%, p=0,020). La proporción de pacientes con hemorragia intracraneal tendió a ser más frecuente en pacientes que posteriormente desarrollaron MAPQ (9 pacientes, 64 %) que en los pacientes con MBP (12 casos, 34%, p=0,055). Los pacientes sometidos a craneotomía posterior (p=0,092) y los que recibían tratamiento esteroideo (p=0,051) mostraron una mayor tendencia a padecer MAPQ. Siete pacientes MBP (20%) presentaron un recuento celular superior a 5000 células/mm3 en el LCR, cifra no encontrada en ningún caso de MAPQ. No se detectaron diferencias en la glucorraquia y proteinorraquia entre ambos grupos. La bacterias más frecuentemente aisladas fueron Staphylococcus coagulasa negativa y S. aureus. En 5 pacientes (14%) se aislaron bacilos gramnegativos no fermentadores (Pseudomonas aeruginosa y Acinetobacter spp). No hubo ningún fallecimiento atribuido a meningitis postquirúrgica.

Conclusión

Los pacientes sometidos a neurocirugía que fueron ingresados por hemorragia cerebral, intervenidos de la fosa posterior o tratados con esteroides presentan una mayor tendencia a presentar MAPQ. Los recuentos celulares en LCR elevados (superiores a 5000 células /mm3) sugieren la existencia de MBP.

PDF

http://scielo.isciii.es/pdf/neuro/v20n2/2.pdf

April 2, 2019 at 6:08 pm

Management of post-neurosurgical meningitis: narrative review.

Clinical Microbiology and Infection September 2017 V.23 N.9 P.621-628.

Hussein K1, Bitterman R2, Shofty B3, Paul M1, Neuberger A4.

Abstract

BACKGROUND:

Infections complicating neurosurgery pose unacceptable mortality and morbidity.

AIMS:

To summarize what is known about the epidemiology, diagnosis and treatment of post-neurosurgical meningitis (PNM).

SOURCES:

PubMed, references of identified studies and reviews, and personal experience when evidence was lacking.

CONTENT:

The incidence and pathogen distribution of PNM is highly variable. A shift towards Gram-negative bacteria has been observed with use of antibiotic prophylaxis and antibiotic-coated devices directed mainly against Gram-positive bacteria. However, knowledge of the local epidemiology is necessary to treat PNM. The diagnosis of PNM is difficult because, unlike community-acquired meningitis, symptoms are less specific; patients are ill at baseline and many neurosurgical conditions mimic meningitis and cause cerebrospinal fluid (CSF) abnormalities. Pivotal CSF findings for diagnosis of PNM are the CSF glucose, CSF lactate and Gram stain. CSF leucocyte counts are not specific in PNM. Current diagnostic capabilities leave a non-negligible category of patients with microbiologically negative, uncertain diagnosis of PNM. There is no high-quality evidence on several cardinal issues in PNM management, including the effectiveness of intraventricular or intrathecal (IV/IT) antibiotics, effectiveness of dual antibiotic therapy for multidrug-resistant Gram-negative bacteria; clinical benefit of routine therapeutic drug monitoring; and safest timing of shunt replacement. Some data point to a potential benefit of IV/IT antibiotic treatment, mainly for PNM caused by carbapenem-resistant Gram-negative bacteria. Carbapenem-colistin combination therapy is suggested for PNM caused by carbapenem-resistant Gram-negative bacteria with a carbapenem MIC ≤8 mg/L.

IMPLICATIONS:

Guiding the optimal management of PNM will necessitate collaborative multicentre efforts and unique study designs.

FULL TEXT

https://www.clinicalmicrobiologyandinfection.com/article/S1198-743X(17)30273-2/fulltext

PDF

https://www.clinicalmicrobiologyandinfection.com/article/S1198-743X(17)30273-2/pdf

April 1, 2019 at 6:34 pm

Intrathecal and intraventricular antibiotics for postoperative Gram-negative meningitis and ventriculitis.

Surg Neurol Int. september 2017 V.8 P.226.

Khan SA1, Waqas M2, Siddiqui UT2, Shamim MS2, Nathani KR2, Jooma R2, Mehmood F3.

Abstract

BACKGROUND:

Postoperative meningitis is a growing cause of concern, especially with the evolution of multidrug-resistant organism. The authors evaluate the use of intraventricular/intrathecal (IVT/IT) antibiotics for postoperative gram-negative meningitis in patients whom intravenous antibiotics were ineffective.

METHODS:

Medical records were retrospectively reviewed and neurosurgery patients with gram-negative postoperative infection meningitis/ventriculitis were enrolled in the study. Their demographics, hospital course, and outcomes were recorded in a pro forma and analyzed using Statistical Package for the Social Sciences, version 19.

RESULTS:

The review identified 21 patients with postneurosurgical gram-negative meningitis/ventriculitis who were treated with IVT or IT antibiotics. The most common organism was Acinetobacter species (n = 14; 66%). Amikacin was used in 7 patients, polymyxin B in 9 patients, and colistin in 5 patients. A combination of antibiotics was used in one patient. Cerebrospinal fluid sterility was achieved in all patients with no incidence of relapse. There was a single death, though that was not related to the infectious process as the patient had a massive pulmonary embolism.

CONCLUSION:

The findings of this study suggest that IVT and IT antibiotic therapy is a useful option in patients who are nonresponsive to standard intravenous therapy with little or no side effects.

FULL TEXT

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5629845/

April 1, 2019 at 6:32 pm

Older Posts


Calendar

June 2019
M T W T F S S
« May    
 12
3456789
10111213141516
17181920212223
24252627282930

Posts by Month

Posts by Category