ISSN:0891-3668    

出版商:OVID    

年代:2001

数据来源: OVID

ISSN:0891-3668    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Background.Pneumococcal surface adhesin A (PsaA) and pneumolysin (Ply) are common to virtually allStreptococcus pneumoniaeisolates, and they are immunogenic and protective against pneumococcal challenge in experimental animals. We have recently shown production of antibodies to PsaA and Ply in young children, but data on the immune response to these antigens during culture-confirmed pneumococcal infection are lacking.Objectives.To evaluate whether young children respond toS. pneumoniaeby producing antibodies to PsaA and Ply during acute otitis media (AOM).Subjects and methods.A cohort of 329 children was followed prospectively from the age of 2 months to the age of 2 years. Paired sera were obtained during episodes of AOM and used to measure antibodies to PsaA and Ply by enzyme-linked immunosorbent assay.S. pneumoniaecultured from the middle ear fluid was taken as evidence of pneumococcal AOM. The presence ofS. pneumoniaein the nasopharyngeal aspirate collected in connection of AOM or any other respiratory infection or in the nasopharyngeal swab collected at scheduled visits was taken to indicate pneumococcal carriage and thus a history of previous contact withS. pneumoniae.Results.Children with previous pneumococcal contacts had high anti-PsaA and anti-Ply concentrations in the acute phase sera regardless of the nature (AOM or carriage) of the current pneumococcal contact. Of the children with no previous pneumococcal contact, those with current pneumococcal AOM had lower antibody concentrations than those with current pneumococcal carriage only. Anti-PsaA and anti-Ply responses were found in children with current pneumococcal contact. The antibody response was strongly associated with low acute phase antibody concentration, but not significantly with age and the nature of the current pneumococcal contact.Conclusions.We showed that infants are capable of developing a specific antibody response to the pneumococcal proteins PsaA and Ply during AOM.

ISSN:0891-3668    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Objective.To determine the safety, tolerance, pharmacokinetics and efficacy of linezolid, a new oxazolidinone antibiotic in the treatment of community-acquired pneumonia in hospitalized children.Design.A Phase II, open label multicenter study of intravenous linezolid followed by oral linezolid suspension, both at a dose of 10 mg/kg every 12 h. Efficacy was assessed at 7 to 14 days after the last dose of linezolid.Patients.Children 12 months to 17 years old with community-acquired pneumonia admitted to the hospital of 14 participating centers.Results.From July 21, 1998, through May 14, 1999, 79 children were enrolled and 78 received linezolid. Sixty-six children completed treatment and follow-up and were evaluable for clinical outcome. The median age of the evaluable patients was 3 years (range, 1 to 12 years); 47 were 2 to 6 years old. Pathogens were isolated from blood or pleural fluid cultures in 8 children:Streptococcus pneumoniae,6 (2 penicillin-resistant); Group AStreptococcus,1; methicillin-resistantStaphylococcus aureus,1. Chest tubes were placed in 9 patients. The mean total duration of intravenous and oral administration was 12.2 ± 6.2 days (range, 6 to 41 days). The mean peak and trough plasma concentrations of linezolid were 9.5 ± 4.8 and 0.8 ± 1.2 &mgr;g/ml, respectively. At the follow-up visit 7 to 14 days after the last dose of linezolid, 61 patients (92.4%) were considered cured including all the patients with proven pneumococcal pneumonia, one failed (methicillin-resistantStaphylococcus aureus) and 4 were considered indeterminate. The most common adverse effects in the intent to treat group were diarrhea (10.3%), neutropenia (6.4%) and elevation in alanine aminotransferase (6.4%).Conclusions.Linezolid was well-tolerated and could be considered an alternative to vancomycin for treating serious infections caused by antibiotic-resistant Gram-positive cocci in children pending results of additional studies.

ISSN:0891-3668    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Background.Respiratory syncytial virus (RSV) is the major viral cause of severe respiratory infections in children younger than 2 years of age. Nevertheless there are not enough epidemiologic data about the role of RSV as a cause of infantile mortality from pneumonia, mainly in young children from developing countriesAim.To determine the frequency of RSV infection in lung tissue samples from Mexican children deceased with pneumonia, by reverse transcription (RT) and PCR.Methods.Postmortem lung tissue samples from 98 children younger than 2 years of age who died of pneumonia during the period of 1989 to 1997 were studied. Paraffin was removed with xylene from 10-&mgr;m lung sections, the total RNA was extracted and complementary DNA was obtained by RT reaction. A nested PCR with the use of oligonucleotides specific for the F glycoprotein gene was developed. Samples negatives for RSV were tested for the absence of polymerase inhibitors and for complementary DNA integrity.Results.Twenty-nine of the 98 (30%) children deceased with pneumonia were positive for RSV by RT-PCR; 8 were detected from 13 (62%) children with histopathologic diagnosis of viral pneumonia and 21 from 85 (25%) children with histopathologic diagnosis of bacterial pneumonia (P= 0.018). There was no significant difference in RSV infection according to age groups or seasonal pattern.Conclusions.RSV infection is frequent in Mexican children younger than 2 years of age who died of pneumonia. Although RSV was more common in viral pneumonia, mixed infections with RSV and bacterial pneumonia were also common.

ISSN:0891-3668    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Background.Acute otitis media (AOM) is a main cause for antimicrobial prescription in Latin America. Pathogen diversity in different geographic regions underscores the need for updated knowledge on AOM microbiology.Aim.To prospectively determine the role of bacteria and viruses in Chilean children with AOM.Methods.Between July, 1998, and June, 1999, children >3 months with a presumptive diagnosis of AOM were referred to the study ear, nose and throat physician. Middle ear fluid and nasopharyngeal aspirates were obtained from children with confirmed AOM and processed for common bacteria,Mycoplasma pneumoniae,Chlamydia pneumoniaeand viruses. Antimicrobial susceptibility patterns and serotypes ofStreptococcus pneumoniaestrains were determined.Results.An ear, nose and throat physician confirmed diagnoses for 222 (42%) of 529 children referred with diagnosis of AOM, and 170 children met eligibility criteria for the study. One or more pathogens were detected in140 of 170 (82%) children. Predominant bacteria wereS. pneumoniae(37%),Haemophilus influenzae(24%) andStreptococcus pyogenes(13%).M. catarrhaliswas detected in 2 children,C. pneumoniaewas found in 1 andM. pneumoniaewas not detected. Viruses were detected in 22 children (13%) from nasopharyngeal aspirates, and in 6 of them the same virus was detected in middle ear fluid. Penicillin-resistant (intermediate and high)S. pneumoniaerepresented 40% of isolates and 10% ofH. influenzaewere beta-lactamase producers. All 10 penicillin-resistantS. pneumoniaestrains were resistant to cefuroxime. EighteenS. pneumoniaeserotypes were detected and 19F was associated with high level penicillin resistance.Conclusion.This study can impact local management of AOM, and it should encourage continuous surveillance of AOM microbiology in Chile and other developing countries.

ISSN:0891-3668    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Background.Urinary tract infection (UTI) is a common problem in children. Because clinical findings and commonly used blood indices are nonspecific, the distinction between lower and upper urinary tract infection cannot be made easily in this population. However, this distinction is important because renal infection can induce parenchymal scarring. The objective of this study was to determine the accuracy of procalcitonin (PCT) compared with C-reactive protein (CRP) rapid tests to predict renal involvement in children with febrile UTI.Methods.PCT and CRP were measured in the blood of children admitted to the emergency room with fever, signs and symptoms of urinary tract infection and/or a positive urine dipstick analysis. Renal parenchymal involvement was assessed by a99mTc-labeled dimercaptosuccinic acid renal scan in the acute phase of infection in all children. Sensitivity, specificity and likelihood ratios were determined for both tests.Results.Fifty-four children with a proven urinary tract infection were enrolled: 63% had renal involvement; and 37% had infection restricted to the lower urinary tract. No difference was found for age, sex and total white blood cell count between the groups. The calculated likelihood ratios of procalcitonin and C-reactive protein rapid tests were between 3.8 and 7 and 1.5 and 2.8, respectively. A positive PCT value predicted renal involvement in 87 to 92% of children with febrile UTI, compared with 44 to 83% using CRP values.Conclusions.A rapid determination of procalcitonin concentration could be useful for the management of children with febrile UTI in the emergency room.

ISSN:0891-3668    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Background.New York City (NYC) pediatricians are now caring for fewer HIV-infected infants and more school age children and adolescents than earlier in the epidemic.Methods.Clinical, laboratory and demographic data were abstracted from medical records at 10 NYC centers participating in the CDC Pediatric Spectrum of HIV Disease project. Pediatric AIDS cases and HIV-related deaths reported to the NYC Department of Health were examined.Results.Median age of HIV-infected children in care increased from 3 years in 1989 to 1991 to 6 years in 1995 to 1998. The number of HIV-infected women giving birth in NYC declined 50% from 1990 to 1997 (1630 to 831); increasing numbers were identified prenatally (14% in 1989; 78% after 1995); and most received prenatal zidovudine prophylaxis (73% in 1997). Estimated perinatal transmission decreased to 10% by 1997. Improved identification of seropositive status in infants was associated with an increased proportion of infected infants receivingPneumocystis cariniipneumonia (PCP) prophylaxis, 84% in 1997. AIDS free survival was longer for children born 1995 to 1998 than for those born before 1995,P= 0.004. In 1998 among children with advanced immunosuppression (CDC category 3), 66% were prescribed 3 or more antiretroviral medicines and 88% received PCP prophylaxis. Citywide AIDS cases and HIV-related deaths fell precipitously beginning in 1996.Conclusions.Based on the observations of this study, the cohort of NYC HIV-infected children in care is aging, associated with a decline in new HIV infections, high rates of PCP prophylaxis and increased time to AIDS. Falling HIV-related deaths citywide support these observations.

ISSN:0891-3668    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Background.With the onset of AIDS increased frequency of Kaposi’s sarcoma (KS) has been reported. However, there is no case-based comparison of childhood (<14 years) KS before and during the HIV pandemic in sub-Saharan Africa. Here we report on the Tanzanian cancer registry data of pediatric KS in Tanzania and implications with regard to pathogenic factors.Methods.One hundred fifty histologically confirmed pediatric KS (PKS) cases registered during 1968 through 1995 (28 years) were analyzed with regard to demographic and clinical characteristics before and during the AIDS epidemic. Statistical analysis was done with the Epi-Info program and chi square test.Results.Of children with PKS 126 (84%) were male and 24 (16%) were female. The gender ratio was 5.1:1 and 5.4:1 during the endemic and epidemic periods, respectively. The highest occurrence of PKS was observed in the 0- to 5-years age group. Overall 73 (4.9/year) of these cases were registered during the pre and 77 (5.9/year) during the AIDS period. Over time a significant increase in anatomically disseminated KS cases was evident during the AIDS epidemic (P= 0.003).Conclusions.These observations indicate that children younger than 5 years are at high risk for developing KS, possibly reflecting low resistance to human herpesvirus (HHV) 8 infection. It is also likely that an increased susceptibility to HHV8 infection and morbidity is related to progressive immunodeficiency. The increase in AIDS PKS incidence appears to reflect a direct or indirect promoting effect of HIV on the development of KS lesions. Recognition of the high KS risk in small children warrants considerations of possible prevention measures including HIV/HHV8 vaccination and therapeutic options.

ISSN:0891-3668    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Objective.To describe the age-specific distribution of typhoid fever including the degree ofSalmonella typhibacteremia among patients evaluated at a large private diagnostic center in Bangladesh, a highly endemic area.Methods.We conducted a prospective-, passive- and laboratory-based study to identify patients withS. typhibacteremia. Subjects (n= 4650) from whom blood cultures were obtained during 16-month period were enrolled from private clinics and hospitals throughout Dhaka. Isolation and quantification ofS. typhifrom blood cultures were performed by the lysis direct plating/centrifugation method.Results.Bacterial pathogens were recovered from blood of 538 of 4650 patients (11.6%) evaluated.S. typhiwas the single most common pathogen recovered, comprising nearly three-fourths of isolates (72.7%; 391 of 538). Isolation rate ofS. typhiwas highest in monsoon and summer seasons and lowest in winter months. The majority (54.5%; 213 of 391) ofS. typhiisolates were from children who were younger than 5 years, and 27% (105 of 391) were from children in the first 2 years of life. The isolation rate was highest (17.4%, 68 of 486) in the second year of life. The number of bacteria in blood on the basis of colony-forming units per ml of blood by age group was inversely related to age.Conclusions.Detection ofS. typhibacteremia in young children in Dhaka, Bangladesh, was considerably higher than previously appreciated, with a peak detection rate in children ≤2 years of age, indicating the need to reassess the age-specific burden of typhoid fever in the community on a regional basis. Contrary to current recommendations this study suggests that development of new vaccines should target infants and young children.

ISSN:0891-3668    

出版商:OVID    

年代:2001

数据来源: OVID