Haemophilus influenzae Type a Meningitis in Immunocompetent Child, Oman, 2015.

Meningitis caused by Haemophilus influenzae type b (Hib) was eliminated in Oman after the introduction of Hib vaccine in 2001. However, a case of H. influenzae type a meningitis was diagnosed in a child from Oman in 2015, which highlights the need to monitor the incidence of invasive non-Hib H. influenzae disease.

Follow-up of cases of Haemophilus influenzae type b meningitis to determine its long-term sequelae.

OBJECTIVE: To measure physical and neurologic impact of Haemophilus influenzae type b (Hib) meningitis on surviving children through short- and long-term follow-up. STUDY DESIGN: Cases of Hib meningitis, diagnosed at a tertiary level pediatric hospital, were subjected to short- and long-term follow-up and compared with age, sex, and area of residence matched healthy controls. Follow-up assessments included thorough physical and neurodevelopmental assessments using a standardized protocol by a multidisciplinary team. RESULTS: Assessments of short-term follow-up cohort (n = 64) revealed hearing, vision, mental, and psychomotor deficits in 7.8%, 3%, 20%, and 25% of the cases, respectively. Deficits were 10%, 1.4%, 21%, and 25% in long-term follow-up cohort (n = 71), in that order. Mental and psychomotor deficits were found in 2% of the controls, none of whom had vision or hearing deficits. CONCLUSIONS: In addition to risk of death, Hib meningitis in children causes severe disabilities in survivors. These data facilitated a comprehensive understanding of the burden of Hib meningitis, specifically in developing countries where disabled children remain incapacitated because of lack of resources and facilities. The evidence generated from this study is expected to provide a compelling argument in favor of introduction and continuation of Hib conjugate vaccine in the national immunization program for children.

The causative pathogen determines the inflammatory profile in cerebrospinal fluid and outcome in patients with bacterial meningitis.

BACKGROUND: The brain's inflammatory response to the infecting pathogen determines the outcome of bacterial meningitis (BM), for example, the associated mortality and the extent of brain injury. The inflammatory cascade is initiated by the presence of bacteria in the cerebrospinal fluid (CSF) activating resident immune cells and leading to the influx of blood derived leukocytes. To elucidate the pathomechanisms behind the observed difference in outcome between different pathogens, we compared the inflammatory profile in the CSF of patients with BM caused by Streptococcus pneumonia (n = 14), Neisseria meningitidis (n = 22), and Haemophilus influenza (n = 9). METHODS: CSF inflammatory parameters, including cytokines and chemokines, MMP-9, and nitric oxide synthase activity, were assessed in a cohort of patients with BM from Burkina Faso. RESULTS: Pneumococcal meningitis was associated with significantly higher CSF concentrations of IFN-γ , MCP-1, and the matrix-metalloproteinase (MMP-) 9. In patients with a fatal outcome, levels of TNF-α, IL-1 ß, IL-1RA, IL-6, and TGF-α were significantly higher. CONCLUSION: The signature of pro- and anti-inflammatory mediators and the intensity of inflammatory processes in CSF are determined by the bacterial pathogen causing bacterial meningitis with pneumococcal meningitis being associated with a higher case fatality rate than meningitis caused by N. meningitidis or H. influenzae.

Acute meningitis prognosis using cerebrospinal fluid interleukin-6 levels.

BACKGROUND: Improved diagnostic tests would aid in diagnosing and treating community-acquired meningitis. OBJECTIVE: To analyze the diagnostic value of interleukin-6 (IL-6) in the cerebrospinal fluid (CSF) of patients presenting with symptoms of acute meningitis. MATERIAL AND METHODS: In a 6-month prospective, observational, cross-sectional emergency department (ED) study, serum and CSF samples were obtained from all patients with a headache and fever in whom the physician suspected meningitis. Patients were excluded if computed tomography findings contraindicated a lumbar puncture, if they had bleeding disorders, or if their serum indicated bleeding. IL-6 levels were measured and compared in patients with (Group A) and without (Group B) bacterial meningitis. RESULTS: Samples were obtained from 53 patients, of whom 40 were ultimately found to have meningitis. These 40 patients averaged 49.6 ± 21.9 years, with number of men 18 (45%), hospitalizations 21 (52%), mortality 3 (.07%), and IL-6 average rating 491 (median: 14.5; range 0000-6000). Findings in the two groups were: Group A (with meningitis): n = 13, average IL-6 level: 1495 (median: 604; 25/75 percentiles: 232.5-2030; 95% confidence interval [CI] 371.7-2618.6; range 64-6000). Group B (with aseptic meningitis): n = 27, average IL-6 level: 7.34 (median: 5; 25/75 percentiles: 0.0/15.1; 95% CI 3.94-10.73; range 0-23.6). Mann-Whitney rank sum test: p < 0.0001. CONCLUSIONS: In patients with acute bacterial meningitis, CSF cytokine concentrations are elevated. Measuring CSF inflammatory cytokine levels in patients with acute meningitis could be a valuable ED diagnostic tool. Using this tool could improve the prognosis of patients with bacterial meningitis by allowing more rapid initiation of antibiotic treatment.

Clear and present danger: in childhood meningitis. The importance of Hib immunisation in infancy and high-risk groups.

The incidence of Haemophilus influenzae type b (Hib) invasive disease has declined significantly in the United Kingdom since the introduction of routine Hib immunisation. However life-threatening Hib infections such as meningitis and epiglottitis may still occur, especially in the unimmunised and immigrant children. A case of Hib meningitis is a reminder that the threat of invasive Hib disease has not been totally eliminated. Early diagnosis and treatment of bacterial meningitis (including Hib meningitis) is essential to prevent death and serious neurological sequelae. Health visitors play a vital role in encouraging parents to have their children immunised without any avoidable delays and in providing reliable information as necessary to back up this advice. Enquiring about immunisation status of all children new to a practice and addressing any omissions, should be routine; immigrant children (and their parents) may be particularly vulnerable and more likely to be inadequately immunised.

Loop-mediated isothermal amplification assay for detection of Haemophilus influenzae type b in cerebrospinal fluid.

Haemophilus influenzae type b (Hib) is one of the leading causes of meningitis in developing countries. To establish and evaluate a novel loop-mediated isothermal amplification (LAMP) assay for Hib, we designed a LAMP primer set targeting the Hib-specific capsulation locus. LAMP detected 10 copies of purified DNA in a 60-min reaction. This indicated that the detection limit of LAMP was >100-fold lower than the detection limits of both a PCR for the detection of bexA and a nested PCR for Hib (Hib PCR). No H. influenzae, other than Hib or control bacteria, was detected. Linear determination ranged from 10 to 1,000,000 microorganisms per reaction mixture using real-time turbidimetry. We evaluated the Hib LAMP assay using a set of 52 randomly selected cerebrospinal fluid (CSF) specimens obtained from children with suspected meningitis. For comparison, the CSF specimens were tested using a conventional Hib PCR assay. Hib was detected in 30 samples using LAMP and in 22 samples using the Hib PCR assay. The Hib PCR showed a clinical sensitivity of 73.3% and a clinical specificity of 100% relative to the Hib LAMP assay. These results suggest that further development and evaluation of the Hib LAMP will enhance the global diagnostic capability for Hib detection.

Meningitis and bacteremia caused by Haemophilus influenzae Type e in an immunocompetent child.

Haemophilus influenzae infection is a well-known cause of serious invasive disease in adults and children. But incidence of the common serotypes are type b, f and a. There is very little information available on invasive disease of Haemophilus influenzae type e (Hie) in China, especially in children. We report a case of an immunocompetent child who was clinically diagnosed with bacterial meningitis with bacteremia caused by Hie. The literature on infection especially meningitis caused by Hie is reviewed.

Results of a multicenter survey of diagnosis and treatment for bacterial meningitis in Japan.

An evaluation committee was organized to evaluate 464 cases of bacterial meningitis treated at 108 nationwide medical facilities participating in this survey between April 2004 and January 2007. There were 413 evaluable cases of bacterial meningitis, including 342 children (82.8%) and 71 adults (17.2%). Haemophilus influenzae (217 cases, 63.5%) and Streptococcus pneumoniae (35 cases, 49.3%) were the most frequent pathogens for meningitis in children and adults, respectively. The most used initial therapy for children was carbapenem + cephalosporin therapy (212 cases, 61.9%). Of the 333 children included in efficacy evaluation, 320 (96.1%) were rated as remission, 10 (3.0%) as partial remission, and three (0.9%) as poor response. The combination therapy with two drugs was also most often used in adults (41 cases, 57.7%). In efficacy analysis in 60 adults, remission was observed in 50 (83.3%), partial remission in five (8.3%) and poor response in five (8.3%). In prognosis analysis, 273 (80.3%) among 340 children were alive at the end of treatment without sequelae, but one (0.3%) died by the end of treatment, and 64 (18.8%) had sequelae. Of all adults, six (8.5%) died of bacterial meningitis and 23 (32.4%) had sequelae at the end of treatment. Among the patients followed up for 1 year, 26 (12.3%) of 211 children and three (7.7%) of 39 adults had sequelae. The selection of drugs and its dose level of many cases were appropriate, but the dose level of several cases was inappropriate. It is necessary to spread the method of proper antibiotic therapy.

Defining the correctness of a diagnosis: differential judgments and expert knowledge.

Approaches that use a simulated patient case to study and assess diagnostic reasoning usually use the correct diagnosis of the case as a measure of success and as an anchor for other measures. Commonly, the correctness of a diagnosis is determined by the judgment of one or more experts. In this study, the consistency of experts' judgments of the correctness of a diagnosis, and the structure of knowledge supporting their judgments, were explored using a card sorting task. Seven expert pediatricians were asked to sort into piles the diagnoses proposed by 119 individuals who had worked through a simulated patient case of Haemophilus influenzae Type B (HIB) meningitis. The 119 individuals had varying experience levels. The expert pediatricians were asked to sort the proposed diagnoses by similarity of content, and then to order the piles based on correctness, relative to the known correct diagnosis (HIB meningitis). Finally, the experts were asked to judge which piles contained correct or incorrect diagnoses. We found that, contrary to previous studies, experts shared a common conceptual framework of the diagnostic domain being considered and were consistent in how they categorized the diagnoses. However, similar to previous studies, the experts differed greatly in their judgment of which diagnoses were correct. This study has important implications for understanding expert knowledge, for scoring performance on simulated or real patient cases, for providing feedback to learners in the clinical setting, and for establishing criteria that define what is correct in studies of diagnostic error and diagnostic reasoning.

The causative organisms of bacterial meningitis in Korean children in 1996-2005.

Bacterial meningitis remains a serious cause of morbidity and mortality in childhood, despite the availability of effective vaccines against Haemophilus influenzae type b (Hib) or Streptococcus pneumoniae. The purpose of this study was to analyze data on bacterial meningitis cases in Korea from 1996 through 2005. The information of all hospitalized bacteria-proven meningitis cases was obtained from 17 university hospitals nationwide. A total of 402 cases were identified. Of these, 125 (29.9%) cases were neonates. Streptococcus agalactiae was the most common bacteria responsible for 99 (24.6%) of all cases regardless of age, followed by S. pneumoniae for 91 (22.6%) and H. influenzae for 67 (16.7%) patients. The common etiology beyond the neonatal period was S. pneumoniae for 91 (33.0%) followed by H. influenzae for 63 (22.8%) patients. The overall case fatality rate was 9.4%, which was similar with that in 1986-1995. In conclusion, S. agalactiae, S. pneumoniae and H. influenzae were important etiologic agents of bacterial meningitis in children in the last 10 yrs. It is required to establish the preventive strategy of the three bacteria. The nationwide epidemiologic study should be continued to evaluate immunization strategy and efficacy.

Haemophilus influenzae type B meningitis in a previously healthy child.

Vaccines have proven successful in virtually eradicating certain infectious diseases that typically attack the pediatric population. Since 1988, when the conjugate vaccine was introduced, the incidence of invasive Haemophilus influenzae type B disease was reduced dramatically. However, immunization rates have decreased in certain parts of the country because of a combination of vaccine shortage and widespread parental perception that vaccines are harmful. We present the case of a previous healthy child, who ultimately succumbed to H. influenzae type B meningitis where multiple factors were likely responsible for his acquisition of the disease.

Haemophilus meningitis in an African neonate: time for active surveillance and institution of appropriate control measure.

BACKGROUND: Childhood routine immunization in Nigeria, like most developing nations, do not include vaccination against Haemophilus influenzae type b (Hib) infection. This is probably because infection with Hib is uncommon in children younger than two months due to passive acquisition of maternal antibodies which protects newborn till about four to six months of life. OBJECTIVE: To illustrate a case of neonatal meningitis caused by Haemophilus influenzae and to highlight its other peculiarities. METHODS: A 22-day old baby presented with excessive crying, refusal of feed, progressive abdominal distension, fever and vomiting. Besides clinical assessment, body fluids were cultured. RESULTS: The baby had tachypnoea (90 bpm), tachycardia (182 bpm), and tympanitic and hypoactive abdomen. The musculoskeletal and central nervous systems appeared clinically normal. Haemophilus influenzae was isolated by culture from the cerebrospinal fluid. The baby responded well to treatment with ceftriaxone and gentamycin. Neurological examination has remained normal after discharge for up to three months at follow-up visit. CONCLUSION: There is the need to provide serological and molecular facilities for typing Nigerian Haemophilus infulenzae strain(s) to enhance the development of appropriate vaccine that will be most suitable for prevention of infection due to this organism in Nigeria. However, presently available Haemophilus influenzae vaccine needs to be listed in the National Programme for Immunization (NPI) for the control of infections associated with this organism especially in childhood.

Burden of Haemophilus influenzae type b disease in Pakistani children.

Estimates of the burden of Haemophilus influenzae type b (Hib) in children in Pakistan are limited. A prospective surveillance was set up in 8 sentinel sites in Karachi and Hyderabad in January 2004. A total of 1481 children aged < 5 years underwent lumbar puncture for suspected acute bacterial meningitis. Specimens from 237 (16.0%) children met the criteria for probable bacterial meningitis, and Hib was detected in 45 of them (19.0%). The minimum detected incidence of Hib meningitis in the Hyderabad area was 7.6 per 100 000 in children < 5 years of age, and 38.1 per 100 000 children < 1 year. Hib vaccination is justified for inclusion in Pakistan's expanded programme of immunization.

Pediatric bacterial meningitis surveillance - African region, 2002--2008.

Sub-Saharan Africa has one of the world's greatest disease burdens of Haemophilus influenzae type b (Hib), Streptococcus pneumoniae, and Neisseria meningitidis infections. In 2000, Hib and S. pneumoniae infections accounted for approximately 500,000 deaths in the region; during the past 10 years, N. meningitidis has been responsible for recurring epidemics resulting in approximately 700,000 cases of meningitis. Introduction of vaccines against bacterial pathogens in Africa has been constrained by competing public health priorities, limited availability of Hib and S. pneumoniae vaccines, suboptimal N. meningitidis vaccine, inadequate funding, and limited information regarding the disease burden associated with these infections. The World Health Organization (WHO) and CDC analyzed data for 2002--2008 from the Pediatric Bacterial Meningitis (PBM) Surveillance Network, which collects information on laboratory-confirmed bacterial meningitis cases among children aged <5 years at sentinel hospitals in countries throughout the WHO African Region. The results of that analysis determined that, during 2002-2008, a total of 74,515 suspected cases of meningitis were reported. Among the 69,208 suspected cases with known laboratory results, 4,674 (7%) samples were culture-positive for the three bacterial infections under surveillance: 2,192 (47%) were positive for S. pneumoniae, 1,575 (34%) for Haemophilus influenzae, and 907 (19%) for N. meningitidis. The majority of the remaining culture results were negative. These and other PBM network findings will help guide strategies for strengthening laboratory and data management capacity at existing sentinel hospitals and for planning future network expansion in the WHO African Region.

[Management strategy for pediatric presumptive bacterial meningitis (diagnosis, surveillance, follow-up)]. / Stratégie de prise en charge (diagnostic, surveillance, suivi) d'une méningite présumée bactérienne de l'enfant.

The epidemiology of bacterial meningitis has changed since the last French consensus in 1996, mainly because of more frequent Haemophilus influenzae B and pneumoccocus vaccination. A research PubMed and Cochrane databases was performed for articles published within the past 12 years, mentioning the diagnosis, surveillance, and follow-up of presumed bacterial meningitis in children. Sixty-one references were included among the 1606 on PubMed and 50 on the Cochrane databases. Additional articles (n=35) were identified using the references of selected articles. The definition of bacterial meningitis was reviewed, particularly when the causal agent was not identified. Clinical and biological criteria for the diagnosis and the place of brain imaging were updated. Guidelines available after the common use of Haemophilus influenzae vaccination were analyzed with their level of evidence. Initial surveillance data and risk factors associated with death or poor outcome were reviewed. The short and long-term follow-up was also analyzed to identify the proper follow-up for children.

[Fulminating meningitis caused by Haemophilus influenzae with rapid progression of severe brain edema similar to acute encephalopathy].

We report a 4-year-old boy with fulminating meningitis caused by Haemophilus influenzae (Hib). He suddenly developed fever, vomiting and then somnolence. As bacterial meningitis was suspected, treatment with antibiotics was started at 12 hours after the onset. However, there was a rapid progression of severe brain edema and brain hernia, leading to clinical brain death. His clinical course and neuroradiological findings mimicked those in patients with acute encephalopathy, with cytokine profiles in cerebrospinal fluid demonstrating a marked increase of inflammatory cytokines. From a review of the literature, fulminating Hib meningitis may be classified into two disease types: DIC plus multiple organ failure and acute brain swelling types. The present case belongs to the latter type, in which cytokine storm seems to play an important pathogenic role.

Diagnosis of bacterial meningitis in Ghana: Polymerase chain reaction versus latex agglutination methods.

Bacterial meningitis is a public health crisis in the northern part of Ghana, where it contributes to very high mortality and morbidity rates. Early detection of the causative organism will lead to better management and effective treatment. Our aim was to evaluate the diagnostic accuracy of Pastorex and Wellcogen latex agglutination tests for the detection of bacterial meningitis in a resource-limited setting. CSF samples from 330 suspected meningitis patients within the northern zone of Ghana were analysed for bacterial agents at the zonal Public Health Reference Laboratory in Tamale using polymerase chain reaction (PCR) and two latex agglutination test kits; Pastorex and Wellcogen. The overall positivity rate of samples tested for bacterial meningitis was 46.4%. Streptococcus pneumoniae was the most common cause of bacterial meningitis within the sub-region, with positivity rate of 25.2%, 28.2% and 28.8% when diagnosed using Wellcogen, Pastorex and PCR respectively. The Pastorex method was 97.4% sensitive while the Wellcogen technique was 87.6% sensitive. Both techniques however produced the same specificity of 99.4%. Our study revealed that the Pastorex method has a better diagnostic value for bacterial meningitis than the Wellcogen method and should be the method of choice in the absence of PCR.

INVASIVE NON-TYPE B HAEMOPHILUS INFLUENZAE DISEASE: REPORT OF EIGHT CASES.

OBJECTIVE: To describe eight cases of invasive non-type b Haemophilus influenzae disease in children admitted to Hospital de Clínicas of Universidade Estadual de Campinas. CASES DESCRIPTION: In 2015, there were eight cases of invasive non-type b H. influenzae disease. We tested the ampicillin sensitivity and beta-lactamase production of the strains identified and performed the genotyping. Molecular typing was determined by Pulsed-Field Gel Electrophoresis. Four patients were diagnosed with bacteremia; in two cases, H. influenzae was detected in the pleural fluid, and two patients had meningitis. Patients with comorbidities represented 37.5% of cases. Except for the strain of one patient - not sent to the reference laboratory -, all were ampicillin-sensitive and non-beta-lactamase-producing. Genotyping identified four non-capsular, one type c, and two type a strains. Molecular typing ruled out nosocomial transmission since all serotypes were distinct regarding genotype. COMMENTS: The rise in cases of invasive non-type b H. influenzae infection was real. There was no nosocomial transmission, and we found no justification for the increase. These data indicate the need for surveillance to correctly diagnose, monitor, and understand the spectrum of non-type b H. influenzae disease.