Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004610 (bacteremia)
 13,199 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two children in a day care facility developed Haemophilus influenzae type b meningitis. The second child was enrolled in the facility after rifampin had been administered to the other attendees. The isolate from the first child was susceptible to rifampin, but the isolate from the second was resistant. Both isolates had identical outer membrane protein PAGE profiles. To investigate the virulence of these isolates, we inoculated infant rats intranasally with either the rifampin-resistant or rifampin-susceptible CSF isolate. The rates of nasal colonization (14 of 20 and eight of eight animals inoculated with the rifampin-resistant and rifampin-susceptible isolates, respectively) did not differ significantly. However, bacteremia occurred less frequently in pups inoculated with the rifampin-resistant strain than in animals inoculated with the susceptible strain (four of 20 vs eight of eight, P less than 0.0001). Nasal washings, blood, and CSF obtained from animals inoculated with the rifampin-resistant isolate were divided and plated on media containing rifampin (1 microgram/ml) or without rifampin. Except for those from one animal, organisms isolated from blood and CSF grew only on medium lacking rifampin, whereas H. influenzae type b growing from nasal washings was frequently found on both media. We conclude that mutation of H. influenzae to rifampin resistance is a hazard of rifampin chemoprophylaxis. Rifampin-resistant isolates have the potential to cause disease in patients and experimental animals, although they may be relatively less pathogenic than the parent, susceptible organism.
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PMID:Pathogenicity of a rifampin-resistant cerebrospinal fluid isolate of Haemophilus influenzae type b. 348 83

The charts of 104 white and 52 black children with bacteremia caused by Streptococcus pneumoniae or Haemophilus influenzae type b were reviewed to determine each patient's white blood cell (WBC) and absolute polymorphonuclear cell (PMN) counts at the time of presentation to the emergency room. Mean WBC and PMN counts were virtually identical for the racial groups, 18,300 vs. 18,700/microliter and 12,900 vs. 13,000/microliter, respectively. Examination of subgroups of white and black children with or without meningitis or other focal infection also revealed no significant differences between races, although significantly lower mean WBC and PMN counts were found in children with, compared to those without, meningitis regardless of race. As an aid to the identification of children at high risk for S. pneumoniae or H. influenzae type b bacteremia, it appears that WBC and PMN counts may be interpreted without regard to race.
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PMID:Similarity in white blood cell counts between white and black children with bacteremia. 349 78

A 2-year-old boy had occult bacteremia with nontypeable Haemophilus influenzae 6 weeks after receiving H. influenzae type b polysaccharide vaccine. Evaluation of his host defense was normal. As determined by outer membrane protein electrophoresis and Southern hybridization analysis, this strain was not related to type b strains. Its virulence in rats was similar to that of another nontypeable strain and less than that of a type b strain.
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PMID:Occult bacteremia with nontypeable Haemophilus influenzae. 349 72

In a multicenter randomized trial, 107 children with bacterial meningitis were initially given either cefuroxime or ampicillin plus chloramphenicol. Patients were alternately assigned to 7- or 10-day courses of the designated antimicrobial regimen. CSF isolates included Haemophilus influenzae type b (89, of which 25% were beta-lactamase positive), Streptococcus pneumoniae, and Neisseria meningitidis. Although mean CSF bactericidal titers against Haemophilus isolates were 1:6 in each treatment group, H. influenzae was cultured from CSF in four of 39 patients receiving cefuroxime, 24 to 48 hours after initiation of therapy, compared with none of 40 patients given ampicillin plus chloramphenicol (P = 0.11). Clinical cure rates were similar (95%); one death occurred in each group. One child given cefuroxime had persistent meningitis after 5 days of therapy, and mastoiditis with secondary bacteremia developed in one on day 10. Three patients had relapse or reinfection. One patient who received cefuroxime for 10 days had a relapse of epiglottitis 17 days later, and of the patients given ampicillin plus chloramphenicol, one had a relapse of meningitis 1 week after 7 days of therapy, and bacteremia developed in one 42 days after completion of 10 days of therapy. No increase in either in-hospital complications or relapses occurred with a 7-day treatment course. Proof of the equivalence of the antibiotic regimens and the efficacy of 7-day courses of treatment, as well as the consequences of delayed CSF sterilization, will require additional investigation.
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PMID:Cefuroxime versus ampicillin plus chloramphenicol in childhood bacterial meningitis: a multicenter randomized controlled trial. 352 32

The authors determined the time required for blood cultures to be detected as positive for the common bacterial pathogens in immunocompetent infants and children with fever who had no apparent source of infection. Records of the bacteriology laboratory were reviewed retrospectively from 1981 to 1984 for blood cultures that were positive for Haemophilus influenzae type b, Streptococcus pneumoniae, Neisseria meningitidis, Salmonella species, and group B streptococcus. Blood culturing by a conventional technique and a radiometric method were compared sequentially. Only four (1.5%) of 268 specimens were detected as positive after the second day of incubation; in each case that detection of bacteremia was delayed there was an identified source of infection. For H. influenzae, but not S. pneumoniae, significantly more bacteremias were detected earlier by the radiometric method. Discontinuation of empiric antibiotic therapy in immunocompetent children with suspected bacteremia and without focal infection appears warranted when blood cultures have been sterile for at least 48 hours.
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PMID:The incubation period necessary for detection of bacteremia in immunocompetent children with fever. Implications for the clinician. 375 93

Fever is one of the most common complaints presented to the child's pediatrician or health provider. Some 20% of children seen in the office or clinic are there because of fever. The first decision the physician faces is over the phone: who should be seen immediately and who can be managed over the phone. The purpose of the consultation and the visit is to separate those with inconsequential febrile illness from those who have serious illnesses, bacterial illnesses in particular, since these could be life-threatening and are amenable to antimicrobial therapy. Many studies performed over the past 10 years are essentially in agreement that high fever in children younger than 2 years includes a subset of about 6 to 10% with bacteremia caused principally by S. pneumoniae and H. influenzae. The higher the fever (particularly over 40%) the higher the risk of bacteremia. Examination of the young child elicits two sets of findings. These are traditional physical clues to a specific diagnosis, such as tachypnea, crepitant rales, stiff neck, swollen joints and others. Additionally there are general observational clues dealing with how sick the child really is. The physician then needs to decide which of several possible laboratory tests need to be done in order to further refine a subset of children at high risk. The white count (less than 5000 or greater than 15,000), the band count (greater than 1500) and the sedimentation rate (greater than 30 mm/hour) have proved useful in various studies, as has examination of the urine.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Management of the febrile patient. 379 16

Conventionally prepared immune serum globulin frequently produces severe side effects when administered intravenously. A modified preparation in which 4 to 5 interchain disulfide bonds have been reduced and alkylated has been made for intravenous use. However, reduction and alkylation may affect Fc-mediated functions of immunoglobulin G, particularly its ability to fix complement by the classical pathway. To determine whether reduction and alkylation alters the protective activity of immune serum globulin in vivo we compared it with two less harshly prepared globulins (pH 4 treated or ultrafiltered) in an infant rat model of Haemophilus influenzae b infection. Antibody binding to the capsular and noncapsular components of H. influenzae b and in vitro bactericidal activity were similar in the globulin preparations. Infant rats were treated with various doses of globulins adjusted to provide identical concentrations of anticapsular antibodies as measured by the Farr radioactive antigen binding assay. At high doses of anticapsular antibody (greater than 1,500 ng per pup), all preparations protected well. At marginal doses (750 ng per pup), however, rats given reduced and alkylated globulin had a significantly greater incidence of bacteremia (P less than 0.05), meningitis (P less than 0.01), and death (P less than 0.05) and a higher magnitude of bacteremia (P less than 0.02) than rats who received pH4-treated or ultrafiltered globulins. These differences were not due to differences in anticapsular antibody concentrations achieved in the serum. The 50% protective serum concentrations of anticapsular antibody in this model were 200 to 300 ng/ml for reduced and alkylated globulin and 100 to 200 ng/ml for acid-treated globulin. Absorption of the globulins with purified H. influenzae b capsule reduced in vitro bactericidal activity and rat protective activity. However, the magnitude of bacteremia was lower in rats receiving absorbed pH 4-treated globulin than in those receiving absorbed reduced and alkylated globulin (P less than 0.05). We conclude that reduced and alkylated immunoglobulin G provides significantly less protective activity against H. influenzae b infection in this model than globulins not so modified, and we suggest that the altered Fc function of the immunoglobulin G, such as the decreased ability to fix complement by the classical pathway or decreased Fc-mediated opsonization, may be responsible for this impairment.
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PMID:Decreased protective efficacy of reduced and alkylated human immune serum globulin in experimental infection with Haemophilus influenzae type b. 387 Nov 95

Nasopharyngeal colonization of infant rats with Haemophilus influenzae type b was investigated by two methods of intranasal inoculation. After traumatic instillation of the bacteria, 100% of the animals became colonized, compared with 75.5% of animals after atraumatic instillation. Among colonized rats, significantly more animals in the traumatic group developed bacteremia compared with those in the atraumatic group. Rats in the traumatic group had an onset of bacteremia at a mean of 2.6 days after inoculation compared with 7.3 days in the atraumatic group. The duration of colonization and bacteremia was the same in both groups. The majority of heavily colonized rats developed bacteremia compared with none of the lightly colonized rats. Thus, the development of bacteremia appeared to be related independently to both heavy colonization and traumatic instillation. Protection against intraperitoneal bacterial challenge with H. influenzae type b developed in rats that had been bacteremic; in the majority of animals, this correlated with the development of serum bactericidal activity. Protection and bactericidal activity were only rarely observed in nonbacteremic rats that had been either heavily or lightly colonized. The development of serum bactericidal activity was not related to either the duration or peak level of bacteremia. Thus, in this rat model, H. influenzae type b nasopharyngeal colonization without bacteremia did not appear to stimulate circulating antibodies that protected the animals against challenge.
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PMID:Role of nasopharyngeal colonization with and without bacteremia in the protection of infant rats against Haemophilus influenzae type b challenge. 387 34

The potential role of extravascular and intravascular replication was studied in initiation of sustained bacteremia in experimental infection due to Haemophilus influenzae type b. When organs and fluid from rats were cultured after intranasal inoculation of the rats with H. influenzae type b, the organism was not recovered from any putative extravascular focus before development of bacteremia. To evaluate the potential contribution of intravascular replication in initiation of bacteremia due to H. influenzae type b, we obtained serial blood cultures after intravenous or intranasal inoculation. Bacterial counts increased exponentially immediately after intravenous and 12-18 hr after intranasal inoculation. Using the same model system, we observed bacteremia due to Streptococcus pneumoniae after intraperitoneal but not intravenous inoculation. After intraperitoneal inoculation, the magnitude of bacteremia in individual rats did not regularly increase exponentially over time. These findings are consistent with extravascular replication leading to bacteremia due to S. pneumoniae and efficient intravascular replication leading to sustained bacteremia due to H. influenzae type b.
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PMID:Role of intravascular replication in the pathogenesis of experimental bacteremia due to Haemophilus influenzae type b. 387 63

The isolator 1.5 Microbial Tube (E. I. du Pont de Nemours & Co., Inc., Wilmington, Del.) is a new blood culture system for detection of bacteremia in children which involves lysis of blood cells and direct plating of blood lysate on agar media. Haemophilus influenzae type b is a major pediatric pathogen and may be associated with low-density bacteremia (less than or equal to 50 CFU per ml), yet the clinical data on the efficacy of this system for recovery of H. influenzae b are limited. We used a rat model of H. influenzae b bacteremia and fresh, whole human blood inoculated in vitro with H. influenzae b to compare the 1.5 Microbial Tube and conventional Trypticase soy broth (BBL Microbiology Systems, Cockeysville, Md.) for the detection of low-density H. influenzae b bacteremia. There was a significantly lower recovery of H. influenzae b from blood of bacteremic rats and from in vitro-inoculated human blood by using the 1.5 Microbial Tube than by using Trypticase soy broth. Studies on the mechanism of this lower recovery suggested that the contents of the 1.5 Microbial Tube are toxic to H. influenzae b in the presence of human blood. Additional clinical data are necessary before the 1.5 Microbial Tube can be recommended for detection of low-density H. influenzae b bacteremia.
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PMID:Comparison of the Du Pont Isolator 1.5 Microbial Tube and Trypticase soy broth for the recovery of Haemophilus influenzae type b in experimental bacteremia. 387 76


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