Molecular characterization and antibiotic resistance of Acinetobacter baumannii in cerebrospinal fluid and blood.

The increasing prevalence of carbapenem-resistant Acinetobacter baumannii (CRAB) caused nosocomial infections generate significant comorbidity and can cause death among patients. Current treatment options are limited. These infections pose great difficulties for infection control and clinical treatment. To identify the antimicrobial resistance, carbapenemases and genetic relatedness of Acinetobacter baumannii isolates from cerebrospinal fluid (CSF) and blood, a total of 50 nonrepetitive CSF isolates and 44 blood isolates were collected. The resistance phenotypes were determined, and polymerase chain reaction (PCR) was performed to examine the mechanisms of carbapenem resistance. Finally, multilocus sequence typing (MLST) was conducted to determine the genetic relatedness of these isolates. It was observed that 88 of the 94 collected isolates were resistant to imipenem or meropenem. Among them, the blaOXA-23 gene was the most prevalent carbapenemase gene, with an observed detection rate of 91.5% (86/94), followed by the blaOXA-24 gene with a 2.1% detection rate (2/94). Among all carbapenem-resistant Acinetobacter baumannii (CRAB) observations, isolates with the blaOXA-23 gene were resistant to both imipenem and meropenem. Interestingly, isolates positive for the blaOXA-24 gene but negative for the blaOXA-23 gene showed an imipenem-sensitive but meropenem-resistant phenotype. The MLST analysis identified 21 different sequence types (STs), with ST195, ST540 and ST208 most frequently detected (25.5%, 12.8% and 11.7%, respectively). 80 of the 94 isolates (85.1%) were clustered into CC92 which showed a carbapenem resistance phenotype (except AB13). Five novel STs were detected, and most of them belong to CRAB. In conclusion, these findings provide additional observations and epidemiological data of CSF and blood A. baumannii strains, which may improve future infection-control measures and aid in potential clinical treatments in hospitals and other clinical settings.

The utility of banana peel extract agar in the presumptive identification of Cryptococcus neoformans.

We prepared a newer growth medium, banana peel extract agar (BPEA) containing the extracts of chopped banana peels for the selective cultivation of Cryptococcus neoformans. Over the medium, the growth resulted in the development of light to the dark brown coloured colonies indicating the chromogenic potential of the BPEA. The organism grown over BPEA was subsequently confirmed as C. neoformans by phenotypic as well as by molecular method. This medium, being cost-effective, may be used in resource-poor settings of the developing or underdeveloped countries for selective isolation of C. neoformans.

Efficacy of intravenous plus intrathecal/intracerebral ventricle injection of polymyxin B for post-neurosurgical intracranial infections due to MDR/XDR Acinectobacter baumannii: a retrospective cohort study.

Background: Post-neurosurgical intracranial infections caused by multidrug-resistant or extensively drug-resistant Acinetobacter baumannii are difficult to treat and associated with high mortality. In this study, we analyzed the therapeutic efficacy of intravenous combined with intrathecal/intracerebral ventricle injection of polymyxin B for this type of intracranial infection. Methods: This retrospective study was conducted from January 2013 to September 2017 at the Second Affiliated Hospital, Zhejiang University School of Medicine (Hangzhou,China) and included 61 cases for which cerebrospinal fluid (CSF) cultures were positive for multidrug-resistant or extensively drug-resistant A. baumannii after a neurosurgical operation. Patients treated with intravenous and intrathecal/intracerebral ventricle injection of polymyxin B were assigned to the intrathecal/intracerebral group, and patients treated with other antibiotics without intrathecal/intracerebral injection were assigned to the intravenous group. Data for general information, treatment history, and the results of routine tests and biochemistry indicators in CSF, clinical efficiency, microbiological clearance rate, and the 28-day mortality were collected and analyzed. Results: The rate of multidrug-resistant or extensively drug-resistant A. baumannii infection among patients who experienced an intracranial infection after a neurosurgical operation was 33.64% in our hospital. The isolated A. baumannii were resistant to various antibiotics, and most seriously to carbapenems (100.00% resistance rate to imipenem and meropenem), cephalosporins (resistance rates of 98.38% to cefazolin, 100.00% to ceftazidime, 100.00% to cefatriaxone, and 98.39% to cefepime). However, the isolated A. baumannii were completely sensitive to polymyxin B (sensitivity rate of 100.00%), followed by tigecycline (60.66%) and amikacin (49.18%). No significant differences in basic clinical data were observed between the two groups. Compared with the intravenous group, the intrathecal/intracerebral group had a significantly lower 28-day mortality (55.26% vs. 8.70%, P = 0.01) and higher rates of clinical efficacy and microbiological clearance (95.65% vs. 23.68%, P < 0.001; 91.30% vs. 18.42%, P < 0.001, respectively). Conclusions: Intravenous plus intrathecal/intracerebral ventricle injection of polymyxin B is an effective regimen for treating intracranial infections caused by multidrug-resistant or extensively drug-resistant A. baumannii.

Prevalence and antibiotic resistance profiles of cerebrospinal fluid pathogens in children with acute bacterial meningitis in Yunnan province, China, 2012-2015.

Acute bacterial meningitis is still considered one of the most dangerous infectious diseases in children. To investigate the prevalence and antibiotic resistance profiles of cerebrospinal fluid (CSF) pathogens in children with acute bacterial meningitis in Southwest China, CSF samples from 179 meningitis patients (3 days to 12 years old) with positive culture results were collected from 2012 to 2015. Isolated pathogens were identified using the Vitek-32 system. Gram stain results were used to guide subcultures and susceptibility testing. The antimicrobial susceptibility of isolates was determined using the disc diffusion method. Of the isolates, 50.8% were Gram-positive bacteria, and 49.2% were Gram-negative bacteria. The most prevalent pathogens were E. coli (28.5%), Streptococcus pneumoniae (17.8%), Staphylococcus epidermidis (10.0%), Haemophilus influenzae type b (9.5%), and group B streptococcus (7.2%). In young infants aged ≤3 months, E. coli was the organism most frequently isolated from CSF (39/76; 51.3%), followed by group B streptococcus (13/76; 17.1%) and Streptococcus pneumoniae (8/76; 10.5%). However, in young infants aged >3 months, the most frequently isolated organism was Streptococcus pneumoniae (24/103; 23.3%), followed by Staphylococcus epidermidis (18/103; 17.5%) and Haemophilus influenzae type b (16/103; 15.5%). Antimicrobial susceptibility tests indicated that for E. coli isolates, the susceptibility rates to aminoglycosides ranged from 56.8% to 100.0%, among them, amikacin was identified as the most effective against E. coli. As for cephalosporins, the susceptibility rates ranged from 29.4% to 78.4%, and cefoxitin was identified as the most effective cephalosporin. In addition, the susceptibility rates of piperacillin/tazobactam and imipenem against E. coli were 86.3% and 100%. Meanwhile, the susceptibility rates of Streptococcus pneumoniae isolates to penicillin G, erythromycin, chloramphenicol, ceftriaxone and tetracycline were 68.8%, 0.0%, 87.5%, 81.3% and 0.0%, respectively. Gentamycin, ofloxacin, linezolid and vancomycin were identified as the most effective antibiotics for Streptococcus pneumoniae, each with susceptibility rates of 100%. It was notable that other emerging pathogens, such as Listeria monocytogenes and group D streptococcus, cannot be underestimated in meningitis.

Correlation of clinical, laboratory and drug susceptibility profiles in 176 patients with culture positive TBM in a tertiary neurocare centre.

Drug resistance has increased the difficulties in control of tuberculosis infection. The present study evaluated the clinical and laboratory features among tuberculous meningitis (TBM) patients and the drug susceptibility of Mycobacterium tuberculosis (M.tb) isolated from CSF. Out of 698 CSF samples, 176 (25.21%) were M.tb culture positive. Among the clinical signs and symptoms, fever, headache and altered sensorium were found to be statistically significant (P<0.05). ELISA was a better predictor of disease and found to be statistically significant (P<0.001) in culture-proven TBM cases. Totally, 57 (32.4%) isolates were resistant to one or more drugs that include 5 (2.8%) multidrug-resistant isolates. In conclusion, the search for antibody in CSF and also CSF chloride can represent as an adjunct in the diagnosis of TBM. Screening of drug susceptibility is a very important factor and would help in better management of the disease.

Neonate with Mycoplasma hominis meningoencephalitis given moxifloxacin.

Mycoplasma hominis is a commensal organism in the genitourinary tract that can cause life-threatening CNS infections in neonates after intrauterine infection or through vertical transmission during birth. We present a case of an 11-day-old neonate presenting with fever and supporting laboratory evidence of a CNS infection. No systemic maternal infection or maternal genitourinary tract infection occurred at the time of delivery. Empirical treatment was initiated, consisting of amoxicillin, cefotaxime, and aciclovir. After clinical deterioration, 16S ribosomal DNA PCR in cerebrospinal fluid detected M hominis, antibiotic treatment was switched to moxifloxacin, and pharmacokinetic data were obtained. This Grand Round illustrates the challenges that exist in the diagnosis and treatment of M hominis meningoencephalitis: bacterial cultures are often negative and recommended empirical antimicrobials do not provide adequate antimicrobial coverage. Optimal antimicrobial treatment regimens for M hominis meningoencephalitis are unknown. Although we describe successful treatment of a neonate with a complicated M hominis meningoencephalitis with moxifloxacin, caution with fluoroquinolone monotherapy (including moxifloxacin) has to be taken into account because resistance to fluoroquinolones has previously been described.

Pediatric lumbar puncture and cerebrospinal fluid analysis.

BACKGROUND: Lumbar puncture (LP) is a commonly performed procedure in pediatrics. Accurate analysis of cerebrospinal fluid (CSF) profile is essential in diagnosing and managing a variety of infectious and inflammatory conditions involving the brain, meninges, and spinal cord. It can also provide useful diagnostic information in the evaluation of possible subarachnoid hemorrhage and demyelinating syndromes, and aid in the diagnosis and management of pseudotumor cerebri. OBJECTIVES: To review anatomic, physiologic, and pathologic aspects of performing pediatric lumbar puncture and CSF analysis. DISCUSSION: Although still a commonly performed procedure in the outpatient setting, effective vaccines to prevent invasive infection due to Streptococcus pneumoniae and Haemophilus influenzae type b have greatly reduced pediatric bacterial meningitis rates due to these pathogens, resulting in decreased opportunity for physician-trainees to perfect this important skill (among nonneonates) during the 3 years of supervised residency training. Success in performing pediatric LP is augmented by a thorough understanding of medical aspects related to this procedure. This article discusses technical aspects involved in successfully performing a lumbar puncture to obtain CSF, and interpreting a CSF profile in children. CONCLUSION: A thorough understanding of anatomic, physiologic, and pathologic considerations regarding performing lumbar puncture and CSF analysis can augment success in diagnosing a variety of potentially serious pediatric conditions.

Bacterial isolates from cerebrospinal fluid of children with suspected acute meningitis in a Nigerian tertiary hospital.

AIMS AND OBJECTIVES: To determine the common aetiolog of acute bacterial meningitis in children and their antibiotic susceptibility pattern. MATERIALS AND METHODS: A retrospective study with a review of cerebrospinal fluid culture reports of paediatric patients aged 0-15 years, suspected of acute meningitis in the Medical Microbiology Department of Aminu Kano Teaching Hospital, Kano, Nigeria from October 2006 to October 2009 from October 2006 to October 2009. RESULTS: A positive culture bacterial isolation rate of 3.3% (n=50/1500) with prevalence of Streptococcus pneumoniae (24%), Neisseria meningitidis (22%), Escherichia coli (16%), Haemophilus influenzae (14%), Group B streptococci (8%) and Enterococci (8%) which were susceptible to ceftriaxone (96%), cefotaxime (95%) and ciprofloxacin (93%) across the bacterial isolates. Neonates were 55% (n=6.8/12.4) most at risk. CONCLUSION: Neonates are the most at risk of acute bacterial meningitis. In the absence of antibiotic susceptibility report, ceftriaxone should be considered as a first choice reliable antibiotic for empirical treatment of meningitis in children, in this environment.

Short course amphotericin B with high dose fluconazole for HIV-associated cryptococcal meningitis.

OBJECTIVE: To define more rapidly effective initial antifungal regimens sustainable in resource-constrained settings. METHODS: Cohort study in SW Uganda: Thirty HIV-seropositive, antiretroviral therapy-naïve, patients with first episode cryptococcal meningitis were treated with high dose fluconazole (1200 mg/d for 2 weeks, then 800 mg/d until ART started) plus amphotericin B (AmB, 1 mg/kg/d), with routine normal saline and potassium supplementation, for the initial 5 days. Outcome measures were early fungicidal activity (EFA), determined by serial quantitative CSF cultures, safety, and mortality. RESULTS: EFA was -0.30 ± 0.11 log CFU/day calculated over the first 2 weeks of treatment, with no reduction in the rate of clearance between days 5 and 14. There was no grade IV hypokalemia or elevated creatinine, and no grade III or IV anemia or elevation of ALT. AmB or high dose fluconazole were not stopped early in any patient. Mortality was 23% at 2, and 28% at 10 weeks. CONCLUSIONS: Short course AmB was associated with rapid clearance of infection and was well-tolerated, suggesting it could be used safely in many centres currently relying on fluconazole monotherapy. Phase III trials are needed in African centres to compare short course with the standard 2-week course of AmB.

Correlation of susceptibility of Cryptococcus neoformans to amphotericin B with clinical outcome.

Testing of Cryptococcus neoformans for susceptibility to antifungal drugs by standard microtiter methods has not been shown to correlate with clinical outcomes. This report describes a modified quantitative broth macrodilution susceptibility method showing a correlation with both the patient's quantitative biological response in the cerebrospinal fluid (CSF) and the survival of 85 patients treated with amphotericin B (AMB). The Spearman rank correlation between the quantitative in vitro measure of susceptibility and the quantitative measure of the number of organisms in the patient's CSF was 0.37 (P < 0.01; 95% confidence interval [95% CI], 0.20, 0.60) for the first susceptibility test replicate and 0.46 (P < 0.001; 95% CI, 0.21, 0.62) for the second susceptibility test replicate. The median in vitro estimated response (defined as the fungal burden after AMB treatment) at 1.5 mg/liter AMB for patients alive at day 14 was 5 CFU (95% CI, 3, 8), compared to 57 CFU (95% CI, 4, 832) for those who died before day 14. These exploratory results suggest that patients whose isolates show a quantitative in vitro susceptibility response below 10 CFU/ml were more likely to survive beyond day 14.

Neurolisteriosis: descripción de siete casos / Neurolisteriosis: description of seven cases

Listeria Monocytogenes is a gram-positive Bacillus that affects immunocompromised patients, newborn, pregnant women and persons over 65 years. Infection is acquired through contaminated food. The Bacillus has predilection for the central nervous system. Its presents most commonly as an acute meningitis, it also presents as a chronic meningitis, cerebritis, rhomboencephalitis, brain and spinal abscess. Diagnosis for L. monocytogenes is made through positive cultures in blood and cerebrospinal fluid (CSF). Magnetic Resonance (MR) also helps to in the diagnosis of neurolisteriosis lesions. We described seven cases with L. Monocytogenes infection during 2007 and 2008, with four cases over the aged of 65 years old. Five presented acute meningitis; two rhomboencephalitis and one patient had meningoencephalitis. Six cases showed inflammatory CSF with pleocytosis with polymorphonuclear prevail and normal glycorrachia. MR showed inflammatory findings in five patients and focal brainstem lesions in two cases, one had acute hydrocephalus due arachnoiditis. Five patients improve clinically and two fatal cases were described. Listeriosis is the third cause of meningitis and should be consider in the differential diagnosis of meningitis with clear fluid, especially with pleocytosis and normal glycorrachia. Other clues of the diagnosis are dizziness with or without nystagmus and brainstem compromise. Arachnoiditis should be avoided with steroidal use. The diagnostic imaging test of choice for brain stem compromise is MR.

La Listeria Monocytogenes es un bacilo Gram-positivo que afecta a pacientes inmunocomprometidos, a niños, embarazadas y personas mayores de 65 años. El modo de adquirirla es la ingestión de alimentos contaminados. El bacilo tiene predilección por el sistema nervioso central, donde su expresión más frecuente es la meningitis aguda, también puede presentarse como meningitis crónica, cerebritis, rombencefalitis, abscesos cerebrales y espinales. El cultivos positivos de L. monocytogenes en muestras de sangre o líquido cefalorraquídeo, permite confirmar el diagnóstico. La Resonancia Magnética de cerebro también contribuye al diagnóstico de las lesiones por neurolisteriosis. Se analizan siete casos de neurolisteriosis ocurridos los a±os 2007 y 2008, entre ellos cuatro pacientes mayores de 65 años. La meningitis aguda fue la forma de presentación en cinco de ellos, dos evolucionaron como rombencefalitis y uno como meningoencefalitis. El LCR fue inflamatorio en seis de los pacientes, con pleocitosis depredominio polinuclear, pero glucorraquia normal. La RM mostró imágenes de aspecto inflamatorio en cinco de los enfermos, dos de ellos tenían lesiones focales del tronco cerebral, uno hizo un hidrocéfalo agudo por aracnoiditis. Cinco pacientes presentaron una evolución clínica favorable y dos fallecieron. Siendo la listeriosis la tercera causa etiológica de meningitis, debe ser considerada en el diagnóstico diferencial de meningitis a líquido claro, especialmente en LCR con abundantes polinucleares y glucosa en rangos normales. Otras claves son la sensación vertiginosa con o sin nistagmus y el compromiso de nervios craneales de origen protuberancial. Debe prevenirse las aracnoiditis con el uso precoz de corticoides. Es obligatorio el estudio con RM en toda sospecha de neurolisteriosis.

Childhood bacterial meningitis in Ibadan, Nigeria--antibiotic sensitivity pattern of pathogens, prognostic indices and outcome.

Bacterial meningitis remains a major cause of morbidity, mortality and neurodisability in childhood, particularly in the developing world where effective vaccines against the usual pathogens responsible for the disease are not in routine use. To describe the patterns and outcome of bacterial meningitis among children admitted into the University College Hospital (UCH), Ibadan, Nigeria. All children who satisfied the case definition for meningitis, admitted into the paediatric wards of the University College Hospital, UCH, Ibadan over a period of 30 months were prospectively enrolled and blood and CSF samples were taken for bacteriological analyses. A total of 97 children, 62 males and 35 females were studied. Their ages ranged between 2 months and 12 years, mean age 33.0 (SD=41.7) months, with 80.4% of the cases below the age of 5 years. Haemophilus influenzae type b (Hib) was the leading pathogen, found in 16 (55.1%) of the 29 cases of definite meningitis. Other isolates include Streptococcus pneumoniae (24.1%), Klebsiella spp (7.0%), Staphylococcus aureus (7.0%), Escherichia coli (3.4%) and Pseudomonas spp. (3.4%). Hib and pneumococcus showed varying degrees of resistance to chloramphenicol, penicillin and cotrimoxazole. Twenty six (26.8%) of the cases died and 67.6% of the survivors developed significant neurological sequele. Bacterial meningitis remains a major cause of childhood mortality and neurodisability. Hib and pneumococcus remain the major pathogens responsible for this dreadful disease in Ibadan, Nigeria. The increasing emergence of antibiotic resistance calls for institution of adequate control measures, particularly routine childhood immunisation against the disease.

[Successful treatment of a patient with multidrug resistant Acinetobacter baumannii meningitis with high dose ampicillin-sulbactam]. / Coklu ilaç dirençli Acinetobacter baumannii menenjiti olgusunun yüksek doz ampisilin-sülbaktam ile basarili tedavisi.

Acinetobacter baumannii is an important pathogen which causes severe nosocomial infections such as meningitis. Multidrug resistance is a growing problem throughout the world. In this report a case of multidrug resistant A.baumannii meningitis, treated with high dose of ampicillin-sulbactam (SAM) was presented. Rhinorrhea and confusion developed on the postoperative seventh day in a 67 years old male patient operated for macroadenoma of the hyphophysis gland. Since the cerebrospinal fluid (CSF) findings indicated a central nervous system infection, nosocomial meningitis was diagnosed and intravenous ceftazidime and vancomycin have started. Blood and CSF cultures of the patient revealed no growth and his general condition has improved. However, fever and confusion emerged again on the 21st day of therapy and the repeat CSF sample revealed increased pressure, purulent appearance, 510/mm3 leukocytes (90% PMNL), 58 mg/dl glucose (simultaneous blood glucose was 144 mg/dl) and 49 mg/dl protein. Direct microscopic examination of CSF revealed gram-negative coccobacilli and A.baumannii was identified in the culture. The isolate was resistant to piperacillin-tazobactam, third generation cephalosporins, aztreonam, ciprofloxacin, carbapenems and aminoglycosides, susceptible to sulbactam ampicillin and colistin. Ampicillin (12 gr) and sulbactam (6 gr) treatment was initiated and at the 72nd hour of the therapy the temperature and conciousness level of the patient returned to normal. Control CSF sample obtained on the 14th day of treatment revealed no leukocytes and no bacterial growth. The treatment was continued for 21 days and the patient recovered without any sequela. Since colistin which is one of the alternative antimicrobial treatment choices for resistant Acinetobacter infections, is not found in Turkey, sulbactam-ampicillin might be an effective and safe choice for the treatment of multi-resistant A. baumannii meningitis if the isolate was proven to be susceptible by antibiotic susceptibility tests.

Haemophilus influenzae type-b and non-b-type invasive diseases in urban children (<5years) of Bangladesh: implications for therapy and vaccination.

OBJECTIVE: To prospectively study the epidemiology and antibiotic resistance of Haemophilus infuenzae isolates from invasive infections in children. METHODS: Children (<5years) with pneumonia, meningitis and septicemia from three hospitals in Dhaka, Bangladesh were enrolled (1999-2003); clinical and laboratory data, and blood for cultures were collected. Cerebrospinal fluid (CSF) of meningitis cases was analyzed (Gram stain, culture and biochemical tests). Hib antigen was detected by latex agglutination (LA) in culture-negative pyogenic CSF and PCR was done for bexA gene in culture- and LA-negative pyogenic CSF. Antibiotic susceptibility was determined by E-Tests and beta-lactamase by nitrocefin stick. RESULTS: Seventy-three cases of H. influenzae infections (46 of 293 meningitis cases, 25 of 1493 pneumonia cases, 2 of 48 septicemia cases) were detected; 63%, 34% and 3% of them had meningitis, pneumonia and septicemia respectively. H. influenzae type b (Hib) caused infections in 80.8% of cases (60.3% meningitis, 20.5% pneumonia). Most (86%) infections clustered in 4-12month infants. The case-fatality in pneumonia was 8% compared to 19% in meningitis. H. influenzae isolates from pneumonia and meningitis children were equally resistant to antibiotics (46% vs 43%). Of 10 drugs tested, isolates were resistant to ampicillin (31%), chloramphenicol (42%), trimethoprim-sulfamethoxazole (44%) and azithromycin (1.4%). Multidrug-resistant (MDR) strains were equally prevalent in Hib (31%) and non-b-type (29%) isolates, and in pneumonia (31%) and meningitis (34%) cases. None was resistant to amoxicillin-clavulanate, ceftriaxone, ciprofloxacin, levofloxacin, moxifloxacin, and gatifloxacin. Of all H. influenzae infections, 40%, 4.4% and 100% of pneumonia, meningitis and septicemia cases were caused by other serotypes or non-typeable strains. All ampicillin-resistant-strains produced beta-lactamase without detection of beta-lactamase-negative-ampicillin-resistant (BLNAR) strains. CONCLUSION: Hib is a leading cause of invasive bacterial infections in infants. Multidrug-resistant H. influenzae is common and requires amoxicillin-clavulanate, ceftriaxone or azithromycin as empirical therapy with specific recommendation for use of ceftriaxone for treatment of meningitis particularly MDR cases. New fluoroquinolines has potential utility. An effective national Hib vaccination programme is essential in Bangladesh although non-Hib infections will remain an issue.

Direct detection of the multidrug resistance genome of Haemophilus influenzae in cerebrospinal fluid of children: implications for treatment of meningitis.

BACKGROUND: Multidrug resistance (MDR), specifically to ampicillin and chloramphenicol, has complicated the treatment of Haemophilus influenzae type b (Hib) meningitis. This is worsened by use of prior antibiotics, which limits identification of the causative agent by culture and increases reliance on antigen detection. OBJECTIVE: We aimed to develop a PCR assay for detecting the family of Haemophilus integrating and conjugative elements (ICEs) represented by ICEHin1056 among antibiotic resistant Hib, and then apply this directly to CSF to diagnose Hib meningitis and predict organism susceptibility, irrespective of culture results. STUDY DESIGN: Primers specific for orf 51 of ICEHin1056 were designed and multiplexed with Bex primers, specific for H. influenzae, and tested on culture positive and negative cases. RESULTS: Of 73 Hib isolates, orf 51 PCR amplicons, predicting the presence of ICEs, were found in all 33 MDR isolates while only in 1 of 33 sensitive strains. The remaining 7 ampicillin susceptible, chloramphenicol and tetracycline resistant strains did not produce a PCR product to orf 51. PCR amplification from CSF specimens of these culture positive cases produced identical results with 100% and 97% positive and negative predictive values, respectively. Multiplex PCR to detect Bex and orf 51 identified another 16 MDR Hib cases among 81 culture-negative CSF samples. CONCLUSIONS: Direct PCR for orf 51 in CSF identified resistance pattern of 51% more Hib strains than culture alone (110 versus 73). The ability to detect MDR, in culture negative Hib meningitis cases has significant implications for better directing antibiotic treatment of meningitis cases and thus for preventing disability and death.

Daptomycin produces an enhanced bactericidal activity compared to ceftriaxone, measured by [3H]choline release in the cerebrospinal fluid, in experimental meningitis due to a penicillin-resistant pneumococcal strain without lysing its cell wall.

Daptomycin monotherapy was superior to ceftriaxone monotherapy and was highly efficacious in experimental pneumococcal meningitis, sterilizing the cerebrospinal fluid (CSF) of three of three rabbits after 4 to 6 h. With daptomycin therapy only a negligible release of [(3)H]choline as marker of cell wall lysis was detectable in the CSF, peaking around 250 cpm/min after 4 h, compared to a peak of around 2,400 cpm/min after 4 to 6 h for the ceftriaxone-treated rabbits.

Genetic and phenotypic characterization of Haemophilus influenzae type b isolated from children with meningitis and their family members in Vietnam.

To investigate Haemophilus influenzae type b (Hib) infection in Vietnamese children under the age of 5 years, cerebrospinal fluid (CSF) samples from patients with meningitis were screened for Hib, and isolates were subjected to evaluation of susceptibility to 12 antibiotics, biotyping, and genotyping with pulsed-field gel electrophoresis (PFGE). The major biotype was type II (68.3%), followed by type I (22.8%). Among 79 Hib isolates, 45 (57%) were beta-lactamase-producing and ampicillin-resistant (44 and 1 isolates produced TEM-1- and ROB-1-type beta-lactamases, respectively), and 34 isolates (43%) were beta-lactamase-nonproducing and ampicillin-sensitive. No beta-lactamase-nonproducing and ampicillin-resistant isolates were found. The PFGE patterns of Hib isolates were highly divergent, but most could be classified into three clusters. We also investigated Hib colonization in household contacts of patients, and found that Hib isolates from the CSF of patients and from nasopharyngeal cavities of household contacts showed the same PFGE patterns. This observation suggested that household contacts of patients are a possible reservoir of Hib.