Mastoiditis Now Affects Adults: A Case Report of an Occurrence of the Disease in an 82-Year-Old Male.

Mastoiditis is typically considered a suppurative complication of otitis media seen in children. Vaccines and therapeutics can change the demographics of diseases. Childhood vaccination against Haemophilus influenza, for example, has shifted the mean age for ear, nose, and throat infections caused by this bug to age 25, whereas this used to be most prevalent in the pediatric age group previously. The authors present the case of an 82-year-old man who had mastoiditis. This case serves as a reminder to avoid anchoring bias when seeing an undifferentiated patient in the emergency department.

Hemophilus influenzae Infection's Association With Decreased Risk of Breast Cancer.

Background: Hemophilus influenzae (H. influenzae) is a common cause of widespread bacterial infections and has been associated with the stabilization of the microbiome. The microbiome, through modulating systemic inflammation with possible upregulation of the NLRP3 inflammasome, may potentiate the development of breast cancer (BC). The purpose of this study was to therefore evaluate the correlation between previous H. influenzae infection and the incidence of BC. Methods: A large national database was used to collect International Classification of Disease Ninth and Tenth Codes to evaluate the incidence of BC between January 2010 and December 2019 in patients with and without H. influenzae history. A retrospective cohort study was performed where these groups of individuals were matched by age range, Charlson Comorbidity Index (CCI), and antibiotic treatment exposure. Significance and relative risk were obtained using standard statistical procedures. Results: A total of 13,599 patients were matched by age range and CCI in both the experimental and control groups. BC incidence was 259 (1.905%) in the H. influenzae group compared to 686 (5.044%) in the control group (P < 2.2 × 10-16; odds ratio (OR) = 0.604, 95% confidence interval (CI): 0.553 - 0.660). Matching by antibiotic treatment exposure resulted in two groups of 3,189 patients, in which BC incidence was 98 (3.073 %) in the H. influenzae group compared to 171 (5.362%) in the control group (P < 2.2 × 10-16; OR = 0.584, 95% CI: 0.515 - 0.661). Conclusion: The study shows a statistically significant correlation between H. influenzae and a reduced incidence of BC. These results warrant further research regarding H. influenzae's role in upregulating the NLRP3 inflammasome and its potential role in BC prevention and treatment.

A case of acute non-typeable Hemophilus influenza infective endocarditis in a patient with hypocomplementemia.

Hemophilus influenzae is a gram-negative bacteria responsible for significant cases of invasive infections, especially in the pediatric population and in immunosuppressed adult patients. Before vaccination, most cases were frequently caused by capsulated or typeable variants. Due to the absence of effective vaccination against the nontypeable variant, it is now responsible for most invasive infections. Predisposing risk factors in adults include asplenia, hypocomplementemia, cancer, human immunodeficiency virus infection, and chronic cardiopulmonary disease. Immunity to the nontypeable variants causing disease is perplexing and not yet wholly described as they are genetically diverse. Infective endocarditis (IE) is a cardiac infection with devastating consequences if not detected earlier and treated appropriately. Gram-positive bacteria are the primary cause of IE overall, followed by gram-negative bacteria. Hemophilus species belong to the HACEK group of gram-negative bacteria responsible for causing IE in the pediatric population more than in adults. Hemophilus species, especially the nontypeable variant, is a rare cause of IE in adults. Here we present a case of IE due to Nontypeable Hemophilus influenzae in a 49-year-old caucasian male with hypocomplementemia.

A Report of Haemophilus influenzae Bacteremia With Acute Pelvic Inflammatory Disease.

Sexually-transmitted organisms that frequently originate from the flora of the lower genital tract are often implicated in pelvic inflammatory disease (PID). Haemophilus influenzae, a pathogen found primarily in the upper respiratory tract, has been rarely associated with PID. Here we report a case of a young woman with PID whose blood cultures grew H . influenzae biotype II, a reminder that the endometrium can be the source of systemic H. influenzae infection when no typical primary focus is found.

First report on the prevalence of bacteria in cystic fibrosis patients (CF) in a tertiary care center in Saudi Arabia.

Introduction: Bacterial infections in CF patients are common and start early in life. The prognosis of the disease is substantially dependent on chronic respiratory infection and inflammation. Pseudomonas aeruginosa (PA) infection or chronic colonization have been established to cause a chronic decline in pulmonary function (PFT), and/or increase CF mortality. Objectives: To obtain the prevalence of all bacterial pathogens in our CF patients and assess their evolution over time. Method: A retrospective review of 327 patients with confirmed CF of all age groups, who had respiratory culture samples at the first visit and on a regular follow-up between January 1, 1990 and December 2018, was conducted. Results: A total of 327 patients had a respiratory culture obtained at presentation. Two hundred and sixteen (66%) of 327 patients are alive, while 111 (34%) have died. Respiratory cultures were taken from nasopharyngeal aspiration (NPA) in 199 patients (61%), tracheal aspirate in 9 (3%), bronchoalveolar lavage (BAL)in one (0.29%), and in 124 patients (38%), sputum was induced. The eastern province contributed to the highest number of patients (122, 37.7%). There is a persistent increase in the prevalence of the common bacteria over the follow-up period of 7 years, namely Hemophilus influenzae (H. influenzae), Staphylococcus aureus (S. aureus), and all Pseudomonas (P. aeruginosa) culture types.Comparing cultures from the first and last follow-up visits, there was an increase in the prevalence of all (P. aeruginosa) cultures from 120 (34%) to 137 (53%), and a decrease in the prevalence of (S. aureus) and (H. influenzae) during the same follow-up period. Conclusion: There is a progressive increase in the number of patients with the most pathogenic types of bacteria because of the advanced age at presentation. As more adult patients are enrolled, there is a need for improved awareness regarding the early eradication of pathogenic bacteria to prevent progressive pulmonary damage.

Immunogenicity and Complications of the Pentavalent Vaccine in Iranian Children.

Objective: Vaccination is one of the most convenient and safe preventive care measures available for children. The Pentavalent vaccine which protects against five major infections including diphtheria, tetanus, pertussis, hepatitis B(HepB) and Haemophilus influenzae type b(Hib) was added to the Iranian national immunization program in November 2014. This study aimed to determine the Pentavalent vaccine adverse events and immunogenicity in an Iranian children population in Sari, northern Iran. Method: In this descriptive-analytical study, children who were vaccinated with three doses of the Pentavalent vaccine were studied. Two venous blood samples were obtained before the first dose and 4 weeks following the last booster dose. Possible local and systemic complications of the vaccine were recorded until 7 days following vaccination. Antibody titers were measured by quantitative ELISA kits and geometric mean titer(GMT) was calculated for each vaccine component before and after 3 doses of vaccine. Statistical analysis was performed by SPSS 20.0 software and Chi-square and Fisher's exact tests were used for analysis. Results: Immunogenicity of the Pentavalent vaccine for tetanus was 100%(GMT:2.52 Eu/mL, 95%CI: 2.22-2.88), Hib 98.7%(GMT:2.44 Eu/mL, 95%CI: 2.06-2.89), HepB 98.7%(GMT:153.54 Eu/mL, 95%CI: 133.73-176.29), diphtheria 93.1%(GMT:0.43 Eu/mL, 95%CI:0.37-0.51) and pertussis were 63.7% (GMT:19.44 Eu/mL, 95%CI:16.42-23.03). The most common systemic complication after vaccination was fever. Also, one infant cried for more than 3 hours after the second dose. Other serious side effects were not observed. Conclusion: The Pentavalent vaccine used in Iran can cause adequate antibody response against diphtheria, tetanus, pertussis, Hib and hepatitis B in most cases with minimal side effects. The immunogenicity of this vaccine is significantly lower for pertussis. In this study, no severe complication leading to contraindication to subsequent injections was reported. So, the present policy in replacing triple DTP vaccine with Pentavalent vaccine should be continued in Iran.

Bilateral empyema secondary to Hemophilus influenzae epiglottitis.

An empyema is a collection of pus in the pleural space, often due to aerobic bacteria, that requires drainage typically done with a small bore chest tube and fibrinolytics. The large majority of empyemas are unilateral. Bilateral empyemas are rare, usually non-infectious and typically require surgical management. We report a case of Hemophilus influenzae epiglottitis complicated by bilateral culture proven empyema successfully managed without surgery. The aim of this report is to present a rare complication of epiglottitis and discuss the theoretical issues with management of multiple infected pleural spaces requiring fibrinolytics.

An Observational Prospective Cohort Study of Incidence and Outcome of Streptococcus pneumoniae and Hemophilus influenzae Infections in Adult Solid Organ Transplant Recipients.

BACKGROUND: Streptococcus pneumoniae (S. pneumoniae) and Hemophilus influenzae (H. influenzae) are among the main vaccine-preventable bacterial infections in immunocompromised individuals including solid organ transplant (SOT) recipients. There is a lack of information about incidence and outcomes of these infections in SOT recipients. METHODS: We determined the incidence of S. pneumoniae and H. influenzae, the related hospitalization, and 30- and 180-days mortality in a large cohort of 1182 adult SOT recipients. We calculated 95% confidence intervals (CI) of incidence rate (IR) using Byar's approximation to the Poisson distribution. RESULTS: The overall IR of S. pneumoniae and H. influenzae were 1086 (95% CI, 796-1448) and 1293 (95% CI, 974-1687) per 100,000 person-years of follow-up (PYFU), respectively. The IR of invasive infections were 76 (95% CI, 21-202) and 25 (95% CI, 2.3-118) per 100,000 PYFU, respectively. Hospital admission was required in >50%, 30-days mortality was 0, and 180-days mortality was 8.8% and 4.5% after S. pneumoniae and H. influenzae infections, respectively. CONCLUSIONS: The IR of invasive S. pneumoniae and H. influenzae infections in SOT recipients were much higher than reports from the general population in Denmark. Furthermore, a large proportion of infected SOT recipients were hospitalized. These findings highlight the need for further studies to assess uptake and immunogenicity of vaccines against S. pneumoniae and H. influenzae in SOT recipients.

Burden of selected infectious diseases covered by UK childhood vaccinations: systematic literature review.

Aim: An overview of recent epidemiology and disease burden, independent of patient age, of diphtheria, tetanus, pertussis, hepatitis B, poliomyelitis and Hemophilus influenzae invasive disease in the UK. Materials & methods: A systematic review was undertaken. Outcomes included incidence, prevalence, risk factors and cost burden. Results: 39 publications were included. Hepatitis B prevalence is high among certain risk groups. A small pertussis risk remains in pregnancy and for infants, which led to the introduction of maternal vaccination. H. influenzae invasive disease cases are limited to rare serotypes. Polio, tetanus and diphtheria are well controlled. Conclusion: The evaluated diseases are currently well controlled, thanks to a comprehensive vaccination program, with a generally low clinical and cost burden.

Levels of antibodies specific to diphtheria toxoid, tetanus toxoid, and Haemophilus influenzae type b in healthy children born to Tdap-vaccinated mothers.

INTRODUCTION: Vaccination of pregnant women protects both women and their newborns against some infectious diseases. Thailand implemented tetanus toxoid (TT) vaccination of pregnant women in 1977, which was replaced by tetanus-diphtheria toxoid (dT) vaccination in 2005. The tetanus-diphtheria-acellular pertussis (Tdap) vaccine has been recommended for pregnant women at 27-36 weeks of gestation since 2012 in several countries. Data on antibody responses to diphtheria toxoid (DT), TT, and Hemophilus influenzae type b (Hib) induced by combined vaccines in children born to TT-vaccinated and/or Tdap-vaccinated mothers are limited. MATERIAL AND METHODS: We investigated anti-DT, anti-TT, and anti-Hib IgG responses in a cohort of Thai children (ClinicalTrial.gov NCT02408926) born to mothers who received a TT-containing and/or the Tdap vaccine during pregnancy. Children born to Tdap-vaccinated mothers were randomized to receive either a hexavalent (Infanrix-hexa) or pentavalent (Quinvaxem) vaccine, whereas children born to TT-vaccinated mothers received only Quinvaxem vaccine at 2, 4, 6, and 18 months of age. IgG levels were evaluated at birth (cord blood), 2 (pre-primary), 7 (post-primary), 18 (pre-booster), and 19 months of age (post-booster) using a commercially available enzyme-linked immunoassay. RESULTS: Seroprotective concentrations of anti-DT, anti-TT, and anti-Hib IgG were achieved in >90% and >99% of children following primary and booster vaccination, respectively. Among children born to Tdap-vaccinated mothers, the pentavalent vaccine induced higher levels of anti-Hib IgG than the hexavalent vaccine after primary and booster vaccination. Significantly higher anti-Hib IgG levels were observed among children receiving the pentavalent vaccine and who were born to TT-vaccinated mothers than among children receiving the pentavalent vaccine and born to Tdap-vaccinated mothers after primary and booster vaccination. CONCLUSIONS: Vaccination with a TT-containing and/or the Tdap vaccine during pregnancy did not compromise the seroprotection rate achieved following primary and booster immunization in individuals receiving either the pentavalent or hexavalent vaccine.

First contact: the role of respiratory cilia in host-pathogen interactions in the airways.

Respiratory cilia are the driving force of the mucociliary escalator, working in conjunction with secreted airway mucus to clear inhaled debris and pathogens from the conducting airways. Respiratory cilia are also one of the first contact points between host and inhaled pathogens. Impaired ciliary function is a common pathological feature in patients with chronic airway diseases, increasing susceptibility to respiratory infections. Common respiratory pathogens, including viruses, bacteria, and fungi, have been shown to target cilia and/or ciliated airway epithelial cells, resulting in a disruption of mucociliary clearance that may facilitate host infection. Despite being an integral component of airway innate immunity, the role of respiratory cilia and their clinical significance during airway infections are still poorly understood. This review examines the expression, structure, and function of respiratory cilia during pathogenic infection of the airways. This review also discusses specific known points of interaction of bacteria, fungi, and viruses with respiratory cilia function. The emerging biological functions of motile cilia relating to intracellular signaling and their potential immunoregulatory roles during infection will also be discussed.

Characterization of acute otitis media otopathogens before the introduction of the pneumococcal conjugated vaccine into the national immunization program in Poland.

BACKGROUND: Bacterial etiologic data for acute otitis media (AOM) otopathogens in Poland are scarce. The aim of this study was to determine the bacterial etiology and antibiotic susceptibility patterns of otopathogens in children prior to the introduction of the pneumococcal conjugated vaccine (PCV) into the national immunization program (NIP) in Poland. METHODS: Demographic and laboratory data of children < 5 years old who underwent tympanocentesis due to AOM in Nieklanska Hospital Warsaw between 2010 and 2016, were collected. All middle ear fluids (MEF) cultures were processed at the hospital according to conventional culture methods. RESULTS: Out of 940 MEF cultures, 407 (43.3%) were positive for 419 isolates. The most common etiologies of positive cultures were: S. pneumonaie, nontypeable H. infuenzae (NTHi), and S. pyogenes. Children aged 12-23 months had significantly more S. pneumoniae and NTHi positive cultures than children <12 months of age. S. pneumoniae isolates non-susceptible to penicillin, erythromycin, and clindamycin, declined over the study period (2010-2016). CONCLUSIONS: This is the largest dataset of MEF isolates from AOM patients in Poland, collected during the pre-PCV period. These data can help determine the appropriate treatment for AOM patients and can serve as a baseline for the period before the introduction of PCV to the NIP in Poland.

Clonal diversity of Haemophilus influenzae carriage isolated from under the age of 6 years children.

OBJECTIVES: Pharyngeal carriers such as H. influenzae seem to constitute the only reservoir and probably the only transmission vehicle of the invasive disease. The aims of this study were to estimate the prevalence of H. influenzae carriage, to characterize antibiotic susceptibility, and to explore genetic diversity of H. influenzae isolates. Sampling was carried out as nasopharynx swabs among children less than 6 years old volunteers. After traditional biochemical tests, isolates were confirmed by targeting omp6 sequence. Following the susceptibility tests, genomic diversity of strains was analyzed by Pulsed-Field Gel Electrophoresis procedure. RESULTS: Out of 328 nasopharynx swabs, 73 strains were identified as H. influenzae. Among H. influenzae isolates, resistance to chloramphenicol (42%) and ampicillin (43%) was observed. Levofloxacin is the most effective antibiotic and the least effect belonged to tetracycline. By genomic analysis of selected H. influenza, 28 PFGE patterns were achieved among which 11 patterns included at least 2 strains. All strains clustered into 25 different clones. The dendrogram analysis of the isolated H. influenzae strains showed that some of these strains had a clonal relationship and common genetic origin. According to our results, antibiotic resistance didn't show any significant correlation with the clonality of strains.

Nontypable Haemophilus influenzae Septicemia and Urinary Tract Infection Associated with Renal Stone Disease.

INTRODUCTION: Haemophilus influenzae commonly causes upper respiratory tract infections and has only rarely been reported etiology of urinary tract infections. Since the introduction of the Haemophilus influenzae b (Hib) vaccine, non-typable haemophilus species now cause the majority of invasive disease in Europe. CASE REPORT: We report a case of an adult man with non-typable Haemophilus influenzae septicemia, urinary tract infection and bilateral renal stone disease. The patient presented with right sided flank pain and a CT scan showed bilateral renal stones and a right sided ureteral stone causing obstruction. RESULTS AND DISCUSSION: Haemophilus influenzae was identified in blood and urine and despite a tendency of increasing antibiotic resistance among Haemophilus influenzae, our strain was susceptible to all antibiotics tested. Treatment consisted of 3 days of intravenous cefuroxime, insertion of a right sided JJ ureteric stent and 5 days of peroral ciprofloxacin after discharge. Physicians and microbiologists should be aware of Haemophilus influenzae as a possible urinary tract pathogen, especially when urinary tract abnormalities are present, and take the risk of antibiotic resistance into consideration at initial treatment.

Prevention of influenza virus induced bacterial superinfection by standardized Echinacea purpurea, via regulation of surface receptor expression in human bronchial epithelial cells.

Viral infections may predispose the airways to secondary bacterial infections that can lead to unfavorable progression of principally self-limiting illnesses. Such complicated respiratory infections include pneumonia, bronchitis, sinusitis, acute otitis media, and sepsis, which cause high morbidity and lethality. Some of the pathogenic consequences of viral infections, like the expression of bacterial adhesion receptors and the disturbance of physical barrier integrity due to inflammation, may create permissive conditions for co-infections. Influenza virus A (H3N2) is a major pathogen that causes secondary bacterial infections and inflammation that lead to pneumonia. The herbal medicine Echinacea purpurea, on the other hand, has been widely used to prevent and treat viral respiratory infections, and recent clinical data suggest that it may prevent secondary infection complications as well. We investigated the role of standardized E. purpurea (Echinaforce® extract or EF) on H3N2-induced adhesion of live nontypeable Haemophilus influenzae (NTHi) and Staphylococcus aureus, along with the expression of bacterial receptors, intracellular adhesion molecule-1 (ICAM-1), fibronectin, and platelet activating factor receptor (PAFr), by BEAS-2B cells. Inflammatory processes were investigated by determining the cellular expression of IL-6 and IL-8 and the involvement of Toll-like receptor (TLR-4) and NFκB p65. We found that influenza virus A infection increased the adhesion of H. influenzae and S. aureus to bronchial epithelial cells via upregulated expression of the ICAM-1 receptor and, to some extent, of fibronectin and PAFr. Echinaforce (EF) significantly reduced the expression of ICAM-1, fibronectin, and PAFr and consequently the adhesion of both bacterial strains. EF also effectively prevented the super-expression of inflammatory cytokines by suppressing the expression of NFκB and possibly TLR-4. These results indicate that E. purpurea has the potential to reduce the risk of respiratory complications by preventing virus-induced bacterial adhesion and through the inhibition of inflammation super-stimulation (cytokine storms).

Immunogenicity and protective immunity against otitis media caused by pneumococcus in mice of Hib conjugate vaccine with PsaA protein carrier.

This study evaluated the immunogenicity and protective immunity of a Hemophilus influenzae b (Hib) polysaccharide conjugate vaccine with the pneumococcal surface adhesin A (PsaA) protein carrier in young mice. The Hib polysaccharide was conjugated with the rPsaA protein carrier, which was produced using recombinant DNA technology. A total of 15 young mice aged 3 weeks to 5 weeks were immunized with the conjugate vaccine, and another 15 young mice of the same age were immunized with the licensed Hib-tetanus toxoid (TT) vaccine. Furthermore, the third group of 15 young mice was inoculated with phosphate buffer saline as control. The immunized mice were inoculated with pneumococcus in the middle ear. Results showed that IgG antibody responses against both the PsaA protein and Hib polysaccharide were observed in the Hib-PsaA group. However, no statistical difference was observed in the titer of IgG against the Hib polysaccharide between Hib-PsaA and Hib-TT groups. The elimination rate of pneumococcus and the inflammation of the middle ear showed the effectiveness of protective immunity against otitis media caused by pneumococcus. Our results suggest that the Hib polysaccharide can be successfully conjugated with rPsaA via amide condensation. This new Hib-PsaA conjugate vaccine can induce both anti-PsaA and anti-Hib immune responses in young mice and elicit effective protection against acute otitis media caused by pneumococcus.

Neurologic Complications of Bacterial Meningitis in Children / 대한소아신경학회지

PURPOSE: This study was performed to investigate clinical findings of acute neurologic complications and risk factors for chronic neurologic complications of bacterial meningitis in children. METHODS: Pediatric patients with community acquired bacterial meningitis diagnosed at Seoul National University Children's Hospital and Bundang Seoul National University Hospital were included. We investigated the relative frequency of neurologic complications and distribution of causative organisms. Chronic neurologic complication was defined as persistent neurologic deficit including recurrent seizures 6 months from the diagnosis. Multiple logistic regression analysis was used to identify risk factors for epilepsy and motor deficits, which were the most frequently reported chronic neurologic complications. RESULTS: A total of 90 cases were included in the study. Thirteen cases with less than 6 months follow-up duration were excluded from the analysis of risk factors for chronic neurologic complications. The mean age at diagnosis was 15.6 months. Streptococcus agalactiae was the most common pathogen accounting for 27 cases, followed by Streptococcus pneumoniae (19 cases), Hemophilus influenzae type b (13 cases), and Neisseria meningitidis (12 cases). Acute neurologic complications were found in 28 cases (31%): cerebral infarction in 16 cases, subdural effusion in 15 cases, and hydrocephalus in 9 cases. Chronic neurologic complications were found in 41 (53%) cases: epilepsy in 28 cases, motor deficit in 16 cases, hearing loss in 6 cases, and cognitive impairment in 4 cases. Cerebral infarction and S. pneumoniae infection were identified as risk factors for epilepsy. Cerebral infarction was a unique risk factor for motor deficit. CONCLUSION: Cerebral infarction is the important risk factor for the development of chronic neurologic complications including epilepsy and motor deficit in pediatric patients with bacterial meningitis.

Detection of nasopharyngeal carriages in children by multiplex reverse transcriptase-polymerase chain reaction / 소아과

PURPOSE: The aim of this study was to determine the prevalence of asymptomatic nasopharyngeal carriages in children using a multiplex reverse transcriptase-polymerase chain reaction (mRT-PCR) assay kit. METHODS: We obtained nasopharyngeal swabs from 33 children without any underlying disease from July 25 to July 28, 2008. The children were free from the signs of respiratory tract infections at the time of sampling. DNA was extracted from the swabs and subjected to multiplex RT-PCR using a primer set for the detection of pneumococci (Seeplex(R) PneumoBacter ACE Detection Seegene, Seoul, Korea). The amplified PCR products were separated on 2% agarose gels and stained with either ethidium bromide or screen tape system (Lab901 Scotland, UK). RESULTS: A total of 33 children (male, 15 female, 18) aged between 3.2 and 16.3 (median, 8.2) years were included in this study. The mRT-PCR detected colonized bacteria (Streptococcus pneumoniae, Hemophilus influenzae, Chlamydia pneumoniae, and Bordetella pertussis) in 30 children (90.9%). Of these, 13 children (39.4%) showed more than 2 bacteria: 12 children were positive for 2 bacteria (S. pneumoniae and H. influenzae) and 1 child was positive for 3 bacteria (S. pneumoniae, H. influenzae, and C. pneumoniae). CONCLUSION: mRT-PCR was found to be a sensitive tool for the detection of asymptomatic nasopharyngeal carriages. Clinical significances of the bacteria detected by mRT-PCR will have to be evaluated in the future.

Diseño y evaluación de una reacción de polimerasa en cadena (RPC) múltiple, para la identificación de bacterias causantes de meningitis aguda en líquido cefalorraquídeo de niños chilenos / Multiplex PCR assay in spinal fluid to identify simultaneously bacterial pathogens associated to acute bacterial meningitis in Chilean children

Background: Acute bacterial meningitis (ABM) is a serious disease that needs rapid diagnosis for an accurate treatment. The most important etiological agents are: Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae type b. Overall pathogen detection rate in patients with ABM in Chile is 83 percent. Aim: To evaluate a Polymerase Chain Reaction (PCR) protocol for simultaneous detection of several pathogens in patients with ABM. Material and methods: We designed and evaluated a multiplex PCR protocol for simultaneous specific genes identifications of S pneumoniae (¡ytA and ply genes), N meningitidis (ctrA, crgA) and H influenzae (bexA) in cerebrospinal fluid (CSF) samples from pediatric patients with suspected diagnosis of ABM. Sensitivity, specificity and minimum detection levels of DNA were determined. Amplifications ofrDNA 16S gene was done to confirm extraction of bacterial DNA. Results: Ninety nine CSF samples were studied, 90 from children with fever and negative CSF culture, and 9 from ABM and positive culture patients. The PCR protocol had a sensitivity of 89 percent, specificity of 100 percent, positive predictive value 100 percent and negative predictive value 99 percent. Conclusions: We observed a high concordance (89 percent) between bacteriological cultures and the PCR protocol results. This diagnostic tool could increase identification of agents in specific settings such as patients previously treated with antibiotics.