Estandarización de un procedimiento espectrofotométrico para la cuantificación de polisacárido capsular de Neisseria meningitidis serogrupo X / Standardization of a spectrophotometric procedure for the quantification of Neisseria meningitidis serogroup X capsular polysaccharide

En el presente trabajo se realiza la estandarización del procedimiento espectrofotométrico de determinación de polisacárido capsular e intermedios de Neisseria meningitidis serogrupo X, mediante la determinación de los grupos fosfodiéster presentes en su estructura, por el método de Chen. Se realizó un análisis de los siguientes criterios para la estandarización: linealidad, precisión (repetibilidad y precisión intermedia) y exactitud. Se demostró mediante el diseño experimental y los procedimientos estadísticos empleados que el método es lineal (r > 0,99), el coeficiente de variación del factor respuesta < 5 por ciento, la desviación estándar relativa de la pendiente < 2 por ciento, no existiendo diferencia estadísticamente significativa entre el intercepto de la ecuación con respecto a cero; exacto, porque no existe diferencia estadísticamente significativa entre la concentración determinada en un material de trabajo y su concentración nominal; también demostró ser repetible, pues el coeficiente de variación de las concentraciones de la muestra evaluada (2,44; 2,43; 0,88 por ciento para las concentraciones bajas, medias y altas, respectivamente) es inferior al 3 por ciento y no existen diferencias estadísticamente significativas entre las medias de los resultados obtenidos por dos analistas, evaluados durante cuatro días a tres niveles de concentración. La precisión intermedia es satisfactoria(AU)

The present work comprises the standardization a spectrophotometric procedure for assessing Neisseria meningitidis, serogroup X capsular polysaccharide and their intermediates of modification, the phosphodiesters groups present in its structure, based on Chen method. An analysis of the following standardization criteria was performed: linearity, precision (repeatability and intermediate precision) and accuracy. It was demonstrated through the experimental design and the statistical procedures used that the method is linear (r > 0.99), the coefficient of variation of the response factor < 5 percent, the relative standard deviation of the slope < 2 percent, with no statistically significant difference between the intercept of the equation with respect to zero; exact, because there is no statistically significant difference between the concentration determined in a work material and its nominal concentration; it also proved to be repeatable, because the coefficient of variation of the concentrations of the sample (2.44; 2.43; 0.88 percent for low, medium and high concentrations respectively) is less than 3 percent and there is no statistically significant difference between the means of the results obtained by two analysts, evaluated for four days at three concentration levels. Its intermediate precision was satisfactory(AU)

A propósito de la epidemia meningocóccica chilena (1941-1942): el niño con shock séptico hace 80 años desde la perspectiva médica y social / About the Chilean meningococcal epidemic (1941-1942): the children with septic shock 80 years ago from a medical and social perspective

Resumen: En nuestro país, la enfermedad meningocóccica presenta una baja endemia y alta letalidad, con exis tencia de brotes epidémicos, algunos de ellos de carácter histórico, como el acaecido durante la pri mera mitad del siglo pasado. La acción de un grupo de médicos, pioneros en los aspectos clínicos, de investigación y docencia, junto al personal de salud que constituía su equipo, inmersos en una política pública sanitaria exitosa, permitieron consolidar el cuidado necesario del niño enfermo de esta grave patología, como también de muchas otras, posibilitando así el desarrollo de una propuesta estructurada y científica a la luz del conocimiento disponible en aquella época. Por ello, luego de 80 años, es importante revisar los diversos aspectos clínicos, fisiopatológicos y terapéuticos, además del contexto hospitalario y social de esta exitosa historia del sistema de salud público chileno.

Abstract: In our country, meningococcal disease has a low endemic and high lethality, with epidemic out breaks; some of them of historical character, like the one happened during the first half of the last century. The action of a group of doctors, pioneers in clinical, research and teaching aspects, together with the health personnel that constituted their team, immersed in a successful public health policy, allowed to consolidate the necessary care of the sick child of this serious pathology, as well as many others, thus enabling the development of a structured and scientific proposal, in the light of the knowledge available at that time. Therefore, after 80 years, it is important to review the various clini cal, pathophysiological and therapeutic aspects, in addition to the hospital and social context, of this successful history of the Chilean public health system.

Rapid response to meningococcal disease cluster in Foya district, Lofa County, Liberia January to February 2018

Introduction: early detection of disease outbreaks is paramount to averting associated morbidity and mortality. In January 2018, nine cases including four deaths associated with meningococcal disease were reported in three communities of Foya district, Lofa County, Liberia. Due to the porous borders between Lofa County and communities in neighboring Sierra Leone and Guinea, the possibility of epidemic spread of meningococcal disease could not be underestimated. Methods: the county incidence management system (IMS) was activated that coordinated the response activities. Daily meetings were conducted to review response activities progress and challenges. The district rapid response team (DRRT) was the frontline responders. The case based investigation form; case line list and contacts list were used for data collection. A data base was established and analysed daily for action. Tablets Ciprofloxacin were given for chemoprophylaxis.Results: sixty-seven percent (67%) of the cases were males and also 67% of the affected age range was 3 to 14 years and attending primary school. The attack rate was 7/1,000 population and case fatality rate was 44.4 % with majority of the deaths occurring within 24-48 hours of symptoms onset. Three of the cases tested positive for Neisseria Meningitidis sero-type W while six cases were Epi-linked. None of the cases had recent meningococcal vaccination and no health-worker infections were registered.Conclusion: this cluster of cases of meningococcal disease during the meningitis season in a country that is not traditionally part of the meningitis belt emphasized the need for strengthening surveillance, preparedness and response capacity to meningitis

Coinfección por astrovirus y Neisseria meningitidis serogrupo B en una niña / Coinfection by astrovirus and Neisseria B meningitidis in a girl

La infección meningocócica tiene una elevada morbimortalidad. Las coinfecciones virales han sido descritas, fundamentalmente, por virus herpes y respiratorios. Se presenta una paciente que ingresó al Servicio de Emergencia con convulsión tónico-clónica, hipotensión, taquicardia y escala de Glasgow posterior baja. En la Unidad de Cuidados Intensivos mantuvo alteración del nivel de conciencia y requirió estabilización hemodinámica. Se inició antibioterapia de amplio espectro. La paciente mostró deposiciones líquidas malolientes, sin sangre, que fueron cultivadas y estudiadas mediante reacción en cadena de la polimerasa. El líquido cefalorraquídeo fue normal. Las deposiciones resultaron positivas para astrovirus. Se confirmó, mediante reacción en cadena de la polimerasa en sangre, la presencia de Neisseria meningitidis serogrupo B. Se presenta el primer caso pediátrico de coinfección por astrovirus y Neisseria meningitidis. Este virus debería incluirse entre las causas de coinfección para descartar en caso de clínica abdominal predominante, vómitos o deposiciones líquidas.

Meningococcal infection associates high morbidity and mortality. Viral coinfection has been described mainly with herpes and respiratory virus. We describe a child who suffered a tonic-clonic seizure with hypotension, tachycardia and low Glasgow Coma Scale. She maintained an altered mental status and required hemodynamic stabilization in the Pediatric Intensive Care Unit. Wide spectrum antibiotherapy was initiated. She suffered large and foul-smelling liquid not bloody stools which were cultured and studied by polymerase chain reaction. The cerebrospinal fluid was normal. Later the polymerase chain reaction stools were positive to astrovirus, and the blood polymerase chain reaction was positive to Neisseria meningitidis group B. As far as we know, this is the first case of astrovirus and Neisseria meningitidis coinfection described in children. This virus should be considered as new cause of viral coinfection to discard if unexplained abdominal pain or vomits and liquid stools are observed.

A cross-sectional study assessing the pharyngeal carriage of Neisseria meningitidis in subjects aged 1-24 years in the city of Embu das Artes, São Paulo, Brazil

ABSTRACT Meningococcal carriage is a prerequisite for invasive infection. This cross-sectional study assessed the pharyngeal carriage prevalence in healthy subjects aged 1-24 years in Embu das Artes city, São Paulo, Brazil. Pharyngeal swabs were examined for the presence of Neisseria meningitidis. The isolates were tested for different serogroups using agglutination and polymerase chain reaction. A logistic regression model assessed any independent association between Neisseria meningitidis carriage and various risk factors. A total of 87/967 subjects (9%, 95% Confidence Interval (CI): 7.3-11.0) tested positive for N. meningitidis: 6.2% (95% CI: 3.8-9.4) in 1-4 years, 8.5% (95% CI: 5.1-13.0) in 5-9 years, 12.5% (95% CI: 7.8-18.6) in 10-14 years, 12.6% (95% CI: 7.4-19.7) in 15-19 years and 9% (95% CI: 4.9-14.9) in 20-24 years age groups. Highest carriage prevalence was observed in adolescents 10-19 years old. Serogroup C was predominant (18.4%) followed by serogroup B (12.6%). The 15-19 years age group showed a significant association between number of household members and carriers of N. meningitidis. This cross-sectional study is the first in Brazil to evaluate meningococcal carriage prevalence and associated factors in a wide age range.

Situación epidemiológica de las meningoencefalitis bacterianas / Epidemiological situation of bacterial meningoencephalitis

Se describen los casos de meningoencefalitis bacterianas exponiendo el análisis histórico de algunas variables y a continuación la información desde la Semana epidemiológica (SE) 1 a la 25 del año 2017 que provienen de la notificación por canales oficiales: SNVS (módulos C2/SIVILA) y SIC (Sistema de Información epidemiológica de CABA). El análisis de las infecciones invasivas no meníngeas será realizado en próximas actualizaciones. Los casos fueron notificados a través de estos sistemas por los efectores públicos y privados de la Ciudad. El análisis de los mismos se realizó de manera individual a fin de evitar duplicaciones, excluyendo los casos descartados e integrando la información en una base unificada. Se incluyeron como residentes de CABA a todos aquellos que se domicilian en la Ciudad y aquellos casos atendidos en efectores de la CABA cuyo domicilio es desconocido al momento del análisis. La construcción de las tasas, se realizó en base a las proyecciones poblacionales aportadas por la Dirección de Estadística y Censos (DGEyC) de la Ciudad Autónoma de Buenos Aires. (AU)

nspA Gene as a specific genetic marker for detection of Neisseria meningitidis causing bacterial meningitis.

Bacterial meningitis caused by Neisseria meningitidis which causes human brain meninges damage, is generally diagnosed from patient cerebrospinal fluid through microscopy, immunological assays, biochemical test, PCR, microarray and biosensors. However, these methods are expensive, time-consuming or non-confirmatory due to certain limitations. A quick PCR based method was developed for detection of bacterial meningitis caused by N. meningitidis using specific primers based on amplification of virulence nspA (Neisseria surface protein A) gene partial sequence (202 bp). The nspA gene amplicon could be used as a genetic marker for minimum detection of 10 ng genomic DNA (G-DNA) of N. meningitidis with high sensitivity only in 80 min, which is least time reported for the confirmation of the disease. However, the lower detection limit was found as low as 1.0 ng G-DNA, but with less sensitivity. The cross-reactivity of the genetic marker was also studied with other possible pathogens. A comparison with the presently available detection methods and our method was also done using patient samples.

Caracterización clínica de los casos de enfermedad meningocóccica por serogrupo W135 confirmados durante el año 2012 en Chile / Clinical characterization of cases with meningococcal disease by W135 group in Chile, 2012

Background: During 2012 in Chile, there were 60 cases of serogroup W135 meningococcal disease, which accounts for 57.7% of identified serogroup cases. Aim: To describe main clinical features of patients with serogroup W135 meningococcal disease confirmed in 2012. Material and Methods: Descriptive study of case series based on retrospective review of medical records. Results: Male patients represented 61.7% and 46.7% were children under 5 years. At first clinical attention, 3.4% of patients were suspected of meningococcal disease, while 83.3% had meningococcemia as final diagnosis. Also at first attention, the most common symptoms or clinical signs were fever ≥ 38.0° C (60.3%), cold symptoms (52.5%), and nausea or vomiting (46.7%). Meningeal signs had a low frequency (8.7%). Diarrhea was the second most common symptom found among deceased patients (55.6%) and statistically higher than survivors (26.8%; p = 0.034). Six cases reported with sequelae: limb amputation, hearing loss or neurological damage, and mortality was 31.7%. Discussion: In 2012, serogroup W135 meningococcal disease reported high mortality, atypical clinical presentation, low initial meningococcal disease diagnosis, and a high number of cases with poor clinical course.

Introducción: En el año 2012 en Chile, se presentaron 60 casos de enfermedad meningocóccica (EM) causadas por serogrupo W135, que representa 57,7% de los casos seroagrupables. Objetivo: Describir las características clínicas de los casos de EM por serogrupo W135 confirmados durante el año 2012. Material y Métodos: Estudio descriptivo, de series de casos basada en la revisión de las fichas clínicas. Resultados: El 61,7% de los casos fueron varones y 46,7% tenía menos de 5 años. En la primera consulta, 3,4% tuvo sospecha de EM, en tanto 83,3% tuvo diagnóstico final de meningococcemia. En la primera consulta, los síntomas y/o signos más frecuentes fueron fiebre ≥ 38,0°C (60,3%), cuadro catarral respiratorio (52,5%) y náuseas y/o vómitos (46,7%). Mientras que los signos de irritación meníngea se presentaron en 8,7%. En los fallecidos la diarrea fue el segundo síntoma más frecuente (55,6%), y estadísticamente superior respecto de los sobrevivientes (26,8%; p = 0,034). Seis casos presentaron secuelas: amputaciones de extremidades, hipoacusia o daño neurológico y la letalidad fue de 31,7%. Discusión: la EM por el serogrupo W135 en el año 2012, tuvo una elevada letalidad, presentación clínica inespecífica, sospecha diagnóstica inicial baja y un alto número de casos cursaron con una mala evolución.

Primary meningococcal polyarthritis in a young man.

We report a rare occurrence of primary meningococcal polyarthritis in a 19-year-old man. The fluid in the elbow joint showed Gram-negative diplococci but the culture was sterile. The diagnosis was confirmed by polymerase chain reaction targeting crgA gene of Neisseria meningitidis.

Immune associated complication in meningococcal disease; a report of two cases

Meningococcal disease is one of the most feared infections in children. In recent years, little attention has been focused on the complications of meningococcal disease in the sub-acute phase, the so-called immune associated complications. Its main features are arthritis, vasculitis, episcleritis, pericarditis and very rarely nephritis. We report two siblings with meningococcal disease. The first developed arthritis and vasculitis while the younger sister developed only arthritis of the right ankle. To the best of our knowledge this is the first case report to be published in Kuwait

Meningococcemia crónica / Chronic menigococcemia

La meningococcemia crónica es una forma clínica infrecuente dentro del espectro de infecciones producido por Neisseria meningitidis. Clásicamente esta forma clínica se caracteriza por fiebre, lesiones cutáneas, compromiso articular, y desarrollo en hemocultivo de la bacteria responsable, habitualmente con ausencia de compromiso meníngeo. Generalmente afecta a adultos jóvenes previamente sanos. Se desconoce la razón por la cual estos pacientes, a diferencia de los que presentan meningitis aguda por Neisseria meningitidis y meningococcemia aguda, pueden sobrevivir sin complicaciones durante semanas en ausencia de tratamiento antibiótico útil. Se ha planteado que debido a la alta sensibilidad de esta bacteria a los antibióticos beta-lactámicos, muchos casos podrían ser tratados inadvertidamente. Describimos un caso de meningococcemia crónica en una mujer joven que presenta un cuadro clásico no reconocido inicialmente.

Chronic meningococcemia is an unfrequent clinical picture within the spectrum of infections produced by Neisseria meningitidis. It is classically characterized by fever, skin lesions and joint involvement, usually without meningeal involvement, and with blood culture growth of the responsible bacteria. It generally affects previously healthy young people. It is unknown why these patients, unlike patients with Neisseria meningitidis’s acute meningitis and with acute meningococcemia, can survive without complications during weeks, in abscence of an useful antibiotic treatment. It has been hypothesized that owing to high susceptibility to beta-lactam antibiotics of Neisseria meningitidis, many cases may be treated inadvertently. We describe a case of chronic meningococcemia in a young woman who presented a classical clinical picture, not recognized initially.

Abdomen agudo como manifestación inicial de meningococemia / Acute abdomen as initial manifestation of menincococcemia

El abdomen agudo como síntoma inicial de meningococemia es una entidad muy poco frecuente y raramente descripta en la bibliografía. Presentamos el caso de un paciente de 4 años de edad, sexo masculino, previamente sano, que consulta por síndrome febril y dolor abdominal de 24 h de evolución. Seinterna en unidad clínico-quirúrgica con diagnóstico de abdomen agudo quirúrgico. El paciente evoluciona desfavorablemente y súbitamente presenta signos compatibles con sepsis grave. Se realiza laparotomía de urgencia; se observa escasa cantidad de líquido citrino libre en cavidad con adenitis mesentérica. Desarrolla luego lesiones purpúricas palpables de rápida progresión en miembros inferiores y evolución al shock séptico. Se aísla en hemocultivos periféricos Neisseria meningitidis serogrupo B. El objetivo de esta publicación es exponer y alertar sobre una modalidad de presentación clínica poco frecuente de la meningococemia, pues el retraso en su diagnóstico y tratamiento impactan sobre la morbimortalidad en la población pediátrica.

Abdominal pain as an initial symptom of meningococcemia is an infrequent entity, rarely described in literature. We present a case of a 4 year-old, male, previously healthy child with a 24 hour history of fever and abdominal pain. He is admitted in a surgical unit with a diagnosis of acute abdomen for surgical resolution. The clinical course turns unfavorably, and patient presents signs of severe sepsis. Urgent laparotomy is performed, observing little brownish fluid and mesenteric adenitis. He then exhibits palpable purpuric rapidly progressive lesions in lower extremities, progressing to septic shock. Later, Neisseria meningitidis serogroup B is isolated from blood cultures.The aim of this article is drawing attention to a nontypical form of manifestation of meningococcemia, as a delayeddiagnosis and treatment has an impact on morbidity and mortality among the pediatric population.

Neisseria meningitidis: a neglected cause of infectious haemorrhagic fever in the amazon rainforest

Neisseria meningitidis has not been seen as a significant cause of infectious haemorrhagic fever in the Amazon inlands; most reported cases are from the city of Manaus, the capital of the State of Amazonas. This picture is sustained by the lack of reliable microbiology laboratories, the perception of the health care workers, and the difficult to reach medical assistance; thus the number of confirmed cases is even lower with no reference of the strains phenotype. We report here the investigation of a case of suspected meningococcemia and his close contacts in a rural community in the Coari Lake, up the Amazon River.

Doença meningocócica: comparação entre formas clínicas / Meningococcal disease: comparison between clinical forms

Visando avaliar formas clínicas da doença meningocócica, foram revistos 201 casos diagnosticados como doença meningocócica, em Hospital Universitário da Universidade Federal Fluminense; durante o período de 1971 a 1996, dos quais 185 preencheram os critérios de inclusão. A caracterização clínico-laboratorial permitiu reagrupá-los nas formas de doença meningocócica com meningite, 18 por cento, meningite e septicemia, 62 por cento, e septicemia, 20 por cento. Dados epidemiológicos disponíveis não diferenciaram formas clínicas. Na meningite meningocócica foi significativamente maior: tempo de história clínica; freqüência de manifestações neurológicas; e positividade da bacterioscopia, cultura e teste do látex no líquor. Na septicemia menigocócica, houve predomínio significativamente de: choque; letalidade e níveis maiores de tempo parcial de tromboplastina. Septicemia meningogócica e septicemia com meningite se diferenciaram da meningite meningocócica quanto a: tempo de história clínica; ocorrência de sinais neurológicos focais; coagulação intravascular disseminada e artrite. Dados clínico-laboratoriais levam a admitir meningite como forma localizada de doença meningocócica, e septicemia com meningite e septicemia como variações de gravidade da forma sistêmica da doença.

In order to asses the clinical forms of meningococcal disease, we reviewed 201 cases diagnosed as meningococcal disease in the University Hospital of the Fluminense Federal University in Rio de Janeiro, 185 of which met the inclusion criteria. Clinical and laboratorial characterization allowed for grouping of the cases as follows: meningococcal meningitis, 18 percent; meningitis with septicemia, 62 percent; and septicemia, 20 percent. Available epidemiological data did not differentiate clinical forms. The following were significantly greater in meningococcal meningitis: duration of clinical history; frequency of neurological manifestations; positive bacterioscopy; culture and latex test in cerebrospinal fluid. The following were significantly predominant in septicemia: shock; fatal outcome and higher partial thromboplastin time. Septicemia and meningitis with septicemia were differentiated from meningococcal meningitis in the following: duration of clinical history; occurrence of focal neurological signs; disseminated intravascular coagulation; and arthritis. Clinical and laboratory data lead us to admit meningococcal meningitis as a localized form of Meningococcal disease, and meningitis with septicemia and septicemia as variations in severity of the systemic form of the disease.

Subclinical infection of the genital tract with Neisseria meningitidis

We report the isolation of Neisseria meningitidis, characterized as B:NT:P1.7, from a female patient's genital tract in an outpatient clinic for HIV care. The gynecology clinic, as part of the follow up, collects specimens from all patients with HIV infection for routine exams and for early laboratory detection of sexually transmitted diseases . A Gram-negative diplococcus was isolated from the cervix of a heterosexual patient with AIDS. Based on this and other reported cases, urogenital infection with N. meningitidis can no longer be considered uncommon. The rising incidence of N. meningitidis isolated from this and similar sites has significant medical and diagnostic implications.

Prevalencia y dinámica de portadores asintomáticos de Neisseria meningitidis en estudiantes universitarios de una escuela militar de Ciudad de la Habana / Prevalence and dynamics of asymptomatic carriers of Neisseria meningitidis in university students at a military school in the City of Havana

Los estudios de portadores proporcionan datos útiles para el seguimiento epidemiológico de la enfermedad meningocócica. Las evidencias indican que un aumento del índice de portadores de N. meningitidis suele preceder y acompañar a brotes y epidemias. Neisseria meningitidis es un patógeno humano estricto y muchos casos invasivos ocurren sin el contacto previo con otros enfermos, luego los portadores asintomáticos deben ser la principal fuente de infección. Para conocer la prevalencia y dinámica de portadores en estudiantes universitarios de una escuela militar de Ciudad de La Habana, durante un período de baja endemicidad (marzo-junio, 1999), se realizó un estudio longitudinal observacional durante cuatro meses, en 163 alumnos. En todos se tomó, el primer lunes de cada mes, exudado de la nasofaringe posterior, según el método convencional del hisopado y siembra en medio de cultivo selectivo. Además, se elaboró una encuesta para analizar los posibles factores de riesgo que favorecen al estado de portador. N. meningitidis se identificó por técnicas convencionales, los sero/subtipos e inmunotipos se clasificaron por ELISA de células enteras con anticuerpos monoclonales. Se observó una prevalencia de portadores del 32% y una dinámica caracterizada por el predominio de portadores persistentes (61%). Los fenotipos NA:NT:P1.NST:L3.7.9 (25%), NA:NT:13:L3,7,9 (19%) fueron los más frecuentes y sólo el 7.6% resultó B4:P1.15:L3.7.9, fenotipo causal de la epidemia ocurrida en Cuba. La reducción del índice de portadores de la cepa epidémica, así como la ausencia del segrupo C, está relacionada con la inmunización masiva realizada en Cuba con VA-MENGOC-BC,entre 1987-90 y con su incorporación al Programa Nacional de Inmunizaciones, desde 1991

Meningococcal disease: history, epidemiology, pathogenesis, clinical manifestations, diagnosis, antimicrobial susceptibility and prevention.

Meningoccocal disease has repeatedly caused outbreaks worldwide. There has been sudden surge of cases of meningococcemia and meningococcal meningitis in early 2005 in Delhi, India and neighboring states of Uttar Pradesh and Haryana. As of June 17, 2005, 429 probable cases of meningococcal disease have been reported in Delhi out of which 128 cases have revealed microbiological evidence of Neisseria meningitidis. It is possible that the number of cases was in excess of the numbers notified. During this episode drug susceptibility testing by MIC method (E-test) using break points recently recommended by NCCLS/CLSI, revealed that all isolates were sensitive to penicillin, ampicillin, rifampicin and ceftriaxone. As regards to ciprofloxacin, about two third of the isolates tested were found to be 'non-susceptible' (MIC =0.03microg/mL- 0.190microg/mL). All the isolates were found resistant to cotrimoxazole (MIC> 16microg/mL). Repeated outbreaks, decreased susceptibility to ciprofloxacin, which is commonly used for chemoprophylaxis of meningococcal disease, highlights the need for a constant surveillance system. Present review deals with various aspects of Neisseria meningitidis and meningococcal disease in view of recent episode.

Management of meningococcemia.

Meningococcemia causes substantial morbidity and mortality worldwide, usually in the term of fulminant disease. This paper reviews the background, pathophysiology, clinical manifestations, and treatment of this entity, along with prevention measures and public health issues to be considered. The authors present updated information on breakthroughs in the understanding of genetic predisposition to invasive disease. The status of adjunctive treatment modalities such as monoclonal antibodies and activated protein C, and progress in conjugate vaccine development and implementation are also addressed.

Valor de la leucopenia durante la primera hora como marcador pronóstico en la enfermedad meningococcica / The value of leukopenia during the first hour of admission as a prognostic marker in meningococcal infection

Objetivo: Conocer el curso temporal del recuento leucocitario (RL) dentro de las primeras 24 horas de evolución de la Enfermedad Meningocóccica (EM) y determinar el valor de la presencia de leucopenia, dentro de la primera hora de admisión, como indicador de gravedad con relación a mortalidad en pacientes con EM. Diseño: Prospectivo de cohorte, no ciego, observacional. Lugar: Area de Cuidados Críticos Pediátricos de un hospital general. Pacientes: Pacientes ingresados en forma consecutiva con diagnóstico de EM durante un periodo de 3 años (1999-2002). Medición: Se cuantificó el RL en cuatro oportunidades desde la primera hora de ingresado hasta las 24 horas de estadía (H0, H1, H6, H12 Y H24). Se consideró leucopenia al RL < 5 000/mm3. Resultados: Se analizaron 75 pacientes con un rango de edad entre 3 meses a 12 años, en quienes hubo confirmación bacteriológica en el 56 por ciento. La letalidad fue de un 6,7 por ciento; todos ellos presentaron Púrpura fulminans. Al momento del ingreso un 15 por ciento era leucopénico (11/75) y en H1 presentaron leucopenia 13 de los 75 (17 por ciento). De los pacientes no leucopénicos el 22 por ciento tuvo una caída del RL, pero sin alcanzar rango de leucopenia. Al ingreso se encontraban hipotensos el 69 por ciento de los pacientes leucopénicos y el 17 por ciento de los pacientes no leucopénicos (RR = 3,9; p < 0,001). Los 5 pacientes fallecidos presentaron leucopenia (5/13 = 38,5 por ciento) en H1 en comparación con ningún fallecido en los no leucopénicos (RR = 2,07; p < 0,001) con una sensibilidad y valor predictivo negativo de 100 por ciento, ambos. El nadir leucocitario de los pacientes fallecidos ocurrió en H1 y fue de 2 100/mm3 (rango 1 200 - 3 100/mm3). Conclusiones: La presencia de leucopenia es mayor en la primera hora de estadía intra UCI y su existencia aumenta al doble el riesgo de morir.