RESUMEN
BACKGROUND: Neonatal herpes simplex virus (HSV) infection and its implications have been well defined. Several methods are recommended to mitigate the risk of maternal transmission of HSV to the neonate, including CS, suppressive antiviral therapy for the mother, and prophylaxis for the infant. The utility of CS in women who present with a duration of rupture of membranes greater than 4 hours remains a question. CASE: We present a case of a woman who presented following 10 hours of rupture of membranes with HSV genital lesions, suspected to be the result of untreated recurrent infection. A CS was done. CONCLUSION: Extensive studies for the presence of HSV by PCR of the placenta and infant failed to detect the virus.
Asunto(s)
Cesárea , Rotura Prematura de Membranas Fetales , Herpes Genital/diagnóstico , Herpesvirus Cercopitecino 1/aislamiento & purificación , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Complicaciones Infecciosas del Embarazo/diagnóstico , Atención Prenatal , Diagnóstico Diferencial , Femenino , Herpes Genital/transmisión , Humanos , Recién Nacido , Embarazo , Recurrencia , Adulto JovenRESUMEN
OBJECTIVES: Emergence of plasmids harbouring bla(NDM-1) is a major public health concern due to their association with multidrug resistance and their potential mobility. METHODS: PCR was used to detect bla(NDM-1) from clinical isolates of Providencia rettgeri (PR) and Klebsiella pneumoniae (KP). Antimicrobial susceptibilities were determined using Vitek 2. The complete DNA sequence of two bla(NDM-1) plasmids (pPrY2001 and pKp11-42) was obtained using a 454-Genome Sequencer FLX. Contig assembly and gap closures were confirmed by PCR-based sequencing. Comparative analysis was done using BLASTn and BLASTp algorithms. RESULTS: Both clinical isolates were resistant to all ß-lactams, carbapenems, aminoglycosides, ciprofloxacin and trimethoprim/sulfamethoxazole, and susceptible to tigecycline. Plasmid pPrY2001 (113â295 bp) was isolated from PR. It did not show significant homology to any known plasmid backbone and contained a truncated repA and novel repB. Two bla(NDM-1)-harbouring plasmids from Acinetobacter lwoffii (JQ001791 and JQ060896) shared 100% similarity to a 15 kb region that contained bla(NDM-1). pPrY2001 also contained a type II toxin/antitoxin system. pKp11-42 (146â695 bp) was isolated from KP. It contained multiple repA genes. The plasmid backbone had the highest homology to the IncFIIk plasmid type (51% coverage, 100% nucleotide identity). The bla(NDM-1) region was unique in that it was flanked upstream by IS3000 and downstream by a novel transposon designated Tn6229. pKp11-42 also contained a number of mutagenesis and plasmid stability proteins. CONCLUSIONS: pPrY2001 differed from all known plasmids due to its novel backbone and repB. pKp11-42 was similar to IncFIIk plasmids and contained a number of genes that aid in plasmid persistence.
Asunto(s)
ADN Bacteriano/genética , Klebsiella pneumoniae/enzimología , Klebsiella pneumoniae/genética , Plásmidos , Providencia/enzimología , Providencia/genética , beta-Lactamasas/genética , Anciano , Canadá , ADN Bacteriano/química , Infecciones por Enterobacteriaceae/microbiología , Femenino , Humanos , Klebsiella pneumoniae/aislamiento & purificación , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Providencia/aislamiento & purificación , Análisis de Secuencia de ADNRESUMEN
OBJECTIVES: To investigate the occurrence and molecular mechanisms associated with carbapenemases in carbapenem-resistant Gram-negative isolates from Canadian cases. METHODS: Twenty hospital sites across Canada submitted isolates for a 1 year period starting 1 September 2009. All Enterobacteriaceae with MICs ≥ 2 mg/L and Acinetobacter baumannii and Pseudomonas aeruginosa with MICs ≥ 16 mg/L of carbapenems were submitted to the National Microbiology Laboratory (NML) where carbapenem MICs were confirmed by Etest and isolates were characterized by PCR for carbapenemase genes, antimicrobial susceptibilities, PFGE and plasmid isolation. RESULTS: A total of 444 isolates (298 P. aeruginosa, 134 Enterobacteriaceae and 12 A. baumannii) were submitted to the NML of which 274 (61.7%; 206 P. aeruginosa, 59 Enterobacteriaceae and 9 A. baumannii) met the inclusion criteria as determined by Etest. Carbapenemase genes were identified in 30 isolates: bla(GES-5) (n = 3; P. aeruginosa), bla(KPC-3) (n = 7; Enterobacteriaceae), bla(NDM-1) (n = 2; Enterobacteriaceae), bla(VIM-2) and bla(VIM-4) (n = 8; P. aeruginosa) bla(SME-2) (n = 1; Enterobacteriaceae) and bla(OXA-23) (n = m9; A. baumannii). PFGE identified a cluster in each of Enterobacteriaceae, P. aeruginosa and A. baumannii corresponding to isolates harbouring carbapenemase genes. Three KPC plasmid patterns (IncN and FllA) were identified where indistinguishable plasmid patterns were identified in unrelated clinical isolates. CONCLUSIONS: Carbapenemases were rare at the time of this study. Dissemination of carbapenemases was due to both dominant clones and common plasmid backbones.
Asunto(s)
Antibacterianos/farmacología , Carbapenémicos/farmacología , Infección Hospitalaria/epidemiología , Bacterias Gramnegativas/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/epidemiología , Resistencia betalactámica , Adulto , Anciano , Anciano de 80 o más Años , Proteínas Bacterianas/genética , Canadá/epidemiología , Infección Hospitalaria/microbiología , ADN Bacteriano/química , ADN Bacteriano/genética , Electroforesis en Gel de Campo Pulsado , Femenino , Bacterias Gramnegativas/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/microbiología , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Datos de Secuencia Molecular , Tipificación Molecular , Plásmidos/análisis , Reacción en Cadena de la Polimerasa , Prevalencia , Análisis de Secuencia de ADN , beta-Lactamasas/genéticaRESUMEN
BACKGROUND: Invasive pneumococcal disease due to Streptococcus pneumoniae can cause mortality and severe morbidity due to sepsis, meningitis and pneumonia, particularly in young children and the elderly. Recurrent invasive pneumococcal disease is rare yet serious sequelae of invasive pneumococcal disease that is associated with the immunocompromised and leads to a high mortality rate. METHOD: This retrospective study reviewed recurrent invasive pneumococcal disease cases from the Canadian Immunization Monitoring Program, ACTive (IMPACT) between 1991 and 2019, an active network for surveillance of vaccine-preventable diseases and adverse events following immunization for children ages 0-16 years. Data were collected from 12 pediatric tertiary care hospitals across all 3 eras of public pneumococcal conjugate vaccine implementation in Canada. RESULTS: The survival rate within our cohort of 180 recurrent invasive pneumococcal disease cases was 98.3%. A decrease of 26.4% in recurrent invasive pneumococcal disease due to vaccine serotypes was observed with pneumococcal vaccine introduction. There was also a 69.0% increase in the rate of vaccination in children with preexisting medical conditions compared with their healthy peers. CONCLUSION: The decrease in recurrent invasive pneumococcal disease due to vaccine-covered serotypes has been offset by an increase of non-vaccine serotypes in this sample of Canadian children.
Asunto(s)
Infecciones Neumocócicas , Adolescente , Anciano , Canadá/epidemiología , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Infecciones Neumocócicas/epidemiología , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas , Estudios Retrospectivos , Vacunación/efectos adversos , Vacunas ConjugadasRESUMEN
This paper describes the work of the National Advisory Committee on Infection Prevention and Control (NAC-IPC), previously Infection Prevention and Control Expert Working Group, a longstanding external advisory body that provides subject matter expertise and advice to the Public Health Agency of Canada (PHAC) on the prevention and control of infectious diseases in Canadian health care settings. Originally established by Health Canada as the Infection Control Guidelines Steering Committee in 1992, this advisory board has been providing expert advice on infection prevention and control (IPC) guideline development for over 25 years. The NAC-IPC provides advice to inform the development of comprehensive or concise guidelines, quick reference guides and interim guidelines (usually for emerging pathogens), working closely with PHAC's national Healthcare-Associated Infections (HAIs) surveillance programs for Canadian health care facilities. PHAC's HAI-IPC professionals conduct the necessary literature research, data extraction, evidence synthesis, evidence grading (where applicable) and scientific writing for the guidelines. Due to the paucity of clinical trials and high quality observational studies to inform recommendations for emerging pathogens, expert opinion is critical for interpreting available evidence. .
RESUMEN
We conducted a systematic review and meta-analysis analysing the existing data on transcutaneous electrical nerve stimulation (TENS) or interferential current (IFC) for chronic low back pain (CLBP) and/or neck pain (CNP) taking into account intensity and timing of stimulation, examining pain, function and disability. Seven electronic databases were searched for TENS or IFC treatment in non-specific CLBP or CNP. Four reviewers independently selected randomized controlled trials (RCTs) of TENS or IFC intervention in adult individuals with non-specific CLBP or CNP. Primary outcomes were for self-reported pain intensity and back-specific disability. Two reviewers performed quality assessment, and two reviewers extracted data using a standardized form. Nine RCTs were selected (eight CLBP; one CNP), and seven studies with complete data sets were included for meta-analysis (655 participants). For CLBP, meta-analysis shows TENS/IFC intervention, independent of time of assessment, was significantly different from placebo/control (p < 0.02). TENS/IFC intervention was better than placebo/control, during therapy (p = 0.02), but not immediately after therapy (p = 0.08), or 1-3 months after therapy (p = 0.99). Analysis for adequate stimulation parameters was not significantly different, and there was no effect on disability. This systematic review provides inconclusive evidence of TENS benefits in low back pain patients because the quality of the studies was low, and adequate parameters and timing of assessment were not uniformly used or reported. Without additional high-quality clinical trials using sufficient sample sizes and adequate parameters and outcome assessments, the outcomes of this review are likely to remain unchanged. SIGNIFICANCE: These data highlight the need for additional high-quality RCTs to examine the effects of TENS in CLBP. Trials should consider intensity of stimulation, timing of outcome assessment and assessment of pain, disability and function.
Asunto(s)
Dolor de la Región Lumbar/terapia , Dolor de Cuello/terapia , Estimulación Eléctrica Transcutánea del Nervio , Personas con Discapacidad , Humanos , Autoinforme , Resultado del TratamientoRESUMEN
A multi-country outbreak of Mycobacterium chimaera infection associated with contaminated heater-cooler devices (HCDs) has been reported, with more than 70 cases in Europe and the United States and two cases in Canada to date. The epidemiological and microbiological characteristics of this outbreak provide evidence for common-source transmission of M. chimaera from the exhaust air of intrinsically contaminated HCDs to patients during cardiac surgery. To date, all reported cases have been associated with Stöckert 3T HCDs manufactured at one plant by LivaNova prior to September 2014. Implantation of prosthetic material increases the risk of infection. Infections usually present as prosthetic valve endocarditis, vascular graft infection or disseminated infection. Reported mortality rates have varied, but were often over 40%. Several measures are recommended to facilitate case-finding and mitigate risk of exposure. The feasibility of some risk mitigation measures and their effectiveness in reducing the risk of exposure are yet to be determined. Until HCDs are redesigned in a manner that prevents water contamination and aerosolization, separating the HCD exhaust air from the operating room air during surgery may be the most effective risk mitigation strategy. However, possible unintended consequences of this approach should be considered. This overview summarizes findings from peer-reviewed and other relevant national documents on key features of the outbreak, including the source, identified risk factors for infection, signs and symptoms of infection, burden of disease, risk mitigation measures, management challenges and knowledge gaps.
RESUMEN
The transmission of sexually transmitted infection (STI) pathogens from an infected donor to the recipient of a semen donation in assisted conception may result not only in acute infection but also in long-term reproductive complications or adverse outcomes of pregnancy, including infection of the offspring. Screening for bacterial STI pathogens, Chlamydia trachomatis and Neisseria gonorrhoeae is strongly recommended because these pathogens can cause serious reproductive complications in the recipients of semen donations and infection in their offspring. Screening for these pathogens should be performed using the most sensitive methods, such as nucleic acid amplified tests. False-negative results due to inhibitory substances in the semen sample should be monitored using amplification controls. Where specimen transport is not a problem and culture facilities are available, N gonorrhoeae can also be detected by culture. Laboratories performing screening should subscribe to proficiency programs and have strict quality controls. Although Trichomonas vaginalis, group B streptococcus and genital mycoplasmas have been associated with adverse outcomes of pregnancy, the frequent finding of these organisms in healthy individuals brings into question the validity of mandatory inclusion of these organisms in the screening panel. Although viral STI pathogens and Treponema pallidum - the causative agent of syphilis - may be detected in semen, their presence may be more sensitively detected through antibody testing of the donor. Screening donors for HIV, hepatitis B and syphilis by serology is uniformly recommended in all of the guidelines, but the value of screening either donors or semen samples for cytomegalovirus, herpes simplex viruses and human papilloma viruses is less clear.
RESUMEN
OBJECTIVE: To identify factors affecting HIV-1 breastfeeding transmission. DESIGN: Longitudinal observational cohort study. METHODS: HIV-1 seropositive pregnant women and seronegative controls were enrolled at a maternity hospital in Nairobi. Women and their children were followed from birth, and data on HIV-1 transmission, breastfeeding, clinical illness, and growth were collected. Specimens for HIV-1 serology and/or polymerase chain reaction were obtained at birth, 2, 6, and 14 weeks, 6, 9, 12, and 18 months, and every 6 months thereafter. Children were classified as HIV-1 uninfected, perinatally, or postnatally infected. Potentially breastfeeding transmission related risk factors were compared between postnatally infected and uninfected children. RESULTS: Among children born to seropositive or seroconverting mothers, 317 were uninfected, 51 infected perinatally and 42 infected postnatally. Identified risk factors for postnatal transmission were maternal nipple lesions (OR = 2.3, CI 95% 1.1-5.0), mastitis (OR = 2.7, CI 95% 1.1-6.7), maternal CD4 cell count < 400 mm3 (OR = 4.4, CI 95% 1.9-9.9), maternal seroconversion while breastfeeding (OR = 6.0, CI 95% 1.8-19.8), infant oral thrush at < 6 months of age (OR = 2.8, CI 95% 1.3-6.2) and breastfeeding longer than 15 months (OR = 2.4, CI 95% 1.2-5.1). All factors, except maternal seroconversion due to its rarity, were independently associated with an increased postnatal transmission risk by multivariate logistic regression analysis. CONCLUSION: In addition perinatal antiretroviral therapies, public health strategies should address: (i) prevention of maternal nipple lesions, mastitis and infant thrush; (ii) reduction of breastfeeding duration by all HIV-1-infected mothers; (iii) absolute avoidance of breastfeeding by those at high risk, and (iv) prevention of HIV-1 transmission to breastfeeding mothers.
Asunto(s)
Lactancia Materna , Infecciones por VIH/prevención & control , Infecciones por VIH/transmisión , Transmisión Vertical de Enfermedad Infecciosa , Candidiasis Bucal/complicaciones , Femenino , VIH-1/fisiología , Humanos , Lactante , Recién Nacido , Mastitis/complicaciones , Factores de RiesgoRESUMEN
In a case-control study of 177 HIV-seropositive and 326 seronegative women and their newborns in Nairobi, Kenya, maternal HIV infection at term was independently associated with travel to other African countries [odds ratio (OR) 4.9, P less than 0.0001], history of a blood transfusion since 1980 (OR 3.5, P = 0.01), history of more than one sexual partner in the previous 5 years (OR 1.8, P = 0.02) and unmarried status (OR 1.8, P = 0.02). Neonates of HIV-positive and HIV-negative women differed little with respect to occurrence of congenital malformations, stillbirths, in-hospital mortality, sex, APGAR score, or gestational age. However, the mean birth weight of singleton neonates of HIV-positive women was significantly lower than that of controls (3090 versus 3220 g, P = 0.005), and birth weight was less than 2500 g in 9% of cases and 3% of controls (OR 3.0, P = 0.007). Among neonates of HIV-seropositive women, birth weight was less than 2500 g in 17% if mothers were symptomatic and 6% if mothers were asymptomatic (OR 3.4, P = 0.08).
Asunto(s)
Infecciones por VIH/fisiopatología , Complicaciones Infecciosas del Embarazo/fisiopatología , Resultado del Embarazo , Adulto , Peso al Nacer , Estudios de Casos y Controles , Anomalías Congénitas , Femenino , Muerte Fetal , Edad Gestacional , Infecciones por VIH/transmisión , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Kenia , Masculino , Embarazo , Factores de RiesgoRESUMEN
T cell responses against HIV-1 have been identified in a number of exposed uninfected populations. We hypothesized that the ability to mount an effective T cell response is partly determined by the human leucocyte antigens (HLA) phenotype of the individual. We examined whether certain HLA supertypes were associated with differential HIV-1 susceptibility in sexually exposed adults and in the setting of mother to child HIV-1 transmission. By multivariate analysis, decreased HIV-1 infection risk was strongly associated with possession of a cluster of closely related class I HLA alleles (A2/6802 supertype) in sexually exposed adults (Hazard ratio=0.42, 95% confidence intervals (CI): 0.22-0.81, P=0.009) and perinatally exposed infants (Odds ratio=0.12, 95% CI: 0.03-0.54, P=0.006). The alleles in this HLA supertype are known in some cases, to present the same peptide epitopes (termed 'supertopes'), for T cell recognition. The identification of HIV-1 supertopes, which are associated with protection from HIV-1 infection, has important implications for the application of epitope-based HIV-l vaccines in a variety of racial groups.
Asunto(s)
Vacunas contra el SIDA/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/prevención & control , VIH-1/inmunología , Antígenos HLA , Adulto , Alelos , Estudios de Cohortes , Femenino , Infecciones por VIH/genética , Infecciones por VIH/transmisión , Antígenos HLA/genética , Humanos , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Kenia , Análisis Multivariante , Embarazo , Factores de Riesgo , Trabajo Sexual , Linfocitos T/inmunologíaRESUMEN
Neonates are more susceptible to infection than adults and exhibit more intense or prolonged clinical symptoms. The extent to which deficiencies in T cell or antigen presenting cell (APC) function underlie hyporesponsiveness is incompletely understood. Here, immune function of cord blood mononuclear cells (CBMC), from healthy, full-term neonates was compared with adult PBMC. As widely reported, polyclonally-stimulated T cell proliferation was found to be equivalent, while IFN gamma responses were markedly lower amongst neonates. Reasoning that such stimuli may elicit responses qualitatively different from those that would be obtained following MHC-dependent, cognate T cell activation, alloantigen-specific responses were evaluated. Strikingly, neonates exhibited IFN gamma, IL-4 and IL-10 production equal to adults in short term primary culture. Both the frequency (Fisher's p < 0.0004) and intensity (< 7.5 vs 36.5 pg/ml; Wilcoxon P = 0.005) of alloantigen stimulated IL-5 responses were elevated among neonates, a finding equally evident using irradiated adult or neonatal cells as stimulators. Finally, the relative capacity of neonatal APC as stimulators of cytokine synthesis was assessed by a novel approach using CBMC as both responders and stimulators in MLR. Irradiated neonatal cells consistently stimulated similar proliferative but substantially lower IFN gamma responses than did adult APC, independent of responder origin. The data argue; (i) T cells are largely immunocompetent at birth, (ii) accessory cell function is not fully mature, and (iii) the widely observed hyporesponsiveness to pathogenes may be primarily due to immaturity of APC function or costimulator molecule expression.
Asunto(s)
Células Presentadoras de Antígenos/inmunología , Recién Nacido/fisiología , Leucocitos Mononucleares/inmunología , Linfocitos T/inmunología , Adulto , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , División Celular/inmunología , Citocinas/análisis , Citocinas/biosíntesis , Femenino , Sangre Fetal/inmunología , Humanos , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucina-10/inmunología , Interleucina-10/metabolismo , Interleucina-4/inmunología , Interleucina-4/metabolismo , Interleucina-5/inmunología , Interleucina-5/metabolismo , Isoantígenos/inmunología , Leucocitos Mononucleares/metabolismo , Activación de Linfocitos , Prueba de Cultivo Mixto de Linfocitos , Fitohemaglutininas/inmunología , Embarazo , Linfocitos T/citología , Linfocitos T/metabolismoRESUMEN
Searching for mechanisms of natural resistance to HIV infection with which to guide HIV vaccine design, we have examined antibody responses to HLA class I antigens in children of HIV-1-infected mothers. Anti-HLA antibodies are known to block HIV infectivity in vitro and can be protective against SIV challenge in macaques immunized with purified class I HLA. It was hypothesized that alloantibody to maternal HLA in children might contribute to the prevention of mother-to-child transmission of HIV-1. In fact, a surprisingly high proportion of the children examined, 22%, were found to have antibody against class I alloantigens. This alloantibody, however, did not correlate with the HIV status of the children and was found in a similar proportion of children of HIV-negative mothers. The HLA specificity of the antibody was not correlated with noninherited maternal HLA alleles and occurred with a higher frequency in older children. This result suggests environmental factors, rather than exposure to maternal cells, are involved in the formation of the alloantibody. The finding that anti-allo-class I HLA antibodies are not associated with a decreased risk of mother-to-child transmission indicates that this humoral immune response is unlikely to be the natural mechanism that accounts for the lack of transmission observed in many births. This result, however, does not preclude the further investigation of cellular alloimmune responses, or the use of alloimmunization as an artificial HIV immunization strategy.
Asunto(s)
Infecciones por VIH/inmunología , VIH-1/inmunología , Antígenos HLA-A/inmunología , Antígenos HLA-B/inmunología , Transmisión Vertical de Enfermedad Infecciosa , Isoanticuerpos/inmunología , Adulto , Factores de Edad , Especificidad de Anticuerpos , Transfusión Sanguínea , Estudios de Cohortes , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Infecciones por VIH/transmisión , Seropositividad para VIH , Humanos , Inmunidad Materno-Adquirida , Lactante , Recién Nacido , Programas Informáticos , Factores de TiempoRESUMEN
OBJECTIVE: To assess the suitability of vaginal washes as specimens for sexually transmitted disease diagnosis and determine the usefulness of PCR technology for Chlamydia trachomatis diagnosis in prepubertal girls. STUDY DESIGN: Paired sets of vaginal secretions were collected with swabs and by vaginal wash from 138 prepubertal girls for evaluation because of alleged sexual abuse. Detection by culture of Neisseria gonorrhoeae and C. trachomatis was compared between the two sampling techniques. PCR techniques were also used to test 29 vaginal wash specimens for C. trachomatis. RESULTS: In the prepubertal girls N. gonorrhoeae was detected in two wash specimens but in only one swab specimen; C. trachomatis was detected by culture in both paired specimens from two children and by PCR in vaginal washes from both of the two children positive by culture; PCR identified two other infected children. CONCLUSIONS: A vaginal wash technique coupled with newer molecular amplification technology may be useful in the assessment of sexually abused children.
Asunto(s)
Chlamydia trachomatis/aislamiento & purificación , Neisseria gonorrhoeae/aislamiento & purificación , Enfermedades Bacterianas de Transmisión Sexual/diagnóstico , Vagina/microbiología , Adolescente , Niño , Abuso Sexual Infantil , Infecciones por Chlamydia/diagnóstico , Femenino , Gonorrea/diagnóstico , Humanos , Reacción en Cadena de la Polimerasa , Pubertad , Sensibilidad y Especificidad , Vaginitis/microbiologíaRESUMEN
Breast-feeding plays a potentially significant role in mother to child transmission of human immunodeficiency virus type 1 (HIV-1). The additional transmission risk attributable to breast-feeding and the factors that enhance or inhibit transmission are presently unknown. One mechanism by which breast milk might inhibit HIV-1 transmission is the presence of specific antibodies directed against HIV-1 in breast milk of seropositive mothers. In this study serum and breast milk samples from women in Nairobi, Kenya, were tested to determine the prevalence of HIV-1 IgA antibodies. A Western blot test developed in our laboratory was used to detect anti-HIV-1 immunoglobulin A in serum and anti-HIV-1 secretory IgA (sIgA) in breast milk. Ninety-four percent of 63 HIV-1 seropositive women had anti-HIV-1 IgA in serum and 59% had anti-HIV-1 sIgA in their breast milk. No significant associations with maternal characteristics or serum anti-HIV-1 IgA or IgG banding patterns and the presence of anti-HIV-1 sIgA in breast milk were found. No protective effect of anti-HIV-1 sIgA was seen regarding mother to child transmission; however, further studies are necessary to determine the effect of these antibodies in maternal sera or in breast milk on the efficacy of HIV-1 transmission.
Asunto(s)
Anticuerpos Anti-VIH/biosíntesis , Seropositividad para VIH/transmisión , VIH-1/inmunología , Inmunoglobulina A/biosíntesis , Transmisión Vertical de Enfermedad Infecciosa , Leche Humana/inmunología , Serodiagnóstico del SIDA , Adulto , Lactancia Materna , Femenino , Anticuerpos Anti-VIH/análisis , Seropositividad para VIH/inmunología , Humanos , Inmunoglobulina A/análisis , Inmunoglobulina G/análisis , Inmunoglobulina G/biosíntesis , Lactante , Recién NacidoRESUMEN
BACKGROUND: Reference lymphocyte subset values for African children are lacking. This study documents these values as well as their alterations associated with perinatal and postnatal HIV-1 transmission and with protection from HIV-1 infection. METHODS: Lymphocyte subsets were determined for HIV-1-seronegative nonpregnant women and their children (controls) and for uninfected, perinatally infected and postnatally infected children born to HIV-1-seropositive mothers in Nairobi, Kenya. The mean, median and 5th and 95th percentile values for CD4+ and CD8+ lymphocyte counts and percentages were determined and compared at the age ranges birth to 3 months, 4 months to 1 year, yearly from 1 to 5 years and from 6 to 10 years of age. RESULTS: Among control children counts differed from published values of other populations. In all age ranges, whereas the absolute values were significantly higher than adult values, the percentages were significantly lower. Children perinatally infected with HIV-1 had clearly distinguishable differences in lymphocyte subset percentages by 3 months of age, when the median CD4+ percentage was 27.9% (5th to 95th percentile, 25.7 to 30.1%) for infected vs. 35.9% (33.3 to 38.7%) for uninfected and 39.9% (37.8 to 42.2%) for control children, P < 0.001; whereas the median CD8+ percentage was 37.0% (33.1 to 41.0%) for infected vs. 27.5% (24.2 to 30.8%) for uninfected and 27.5% (24.2 to 30.8%) for control children, P = 0.001. Differences between uninfected and control children disappeared after 1 year of age. CONCLUSIONS: Normal lymphocyte subset values among African children differ from those in other populations. Significant differences are detectable by 3 months of age in CD4+ and CD8+ lymphocyte percentages among perinatally infected infants, which may be useful as an adjunct in diagnosis. Transient differences observed among HIV-1-exposed but uninfected infants could reflect a successful immune response to HIV-1 challenge.
Asunto(s)
Infecciones por VIH/inmunología , Subgrupos de Linfocitos T , Recuento de Linfocito CD4 , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Niño , Preescolar , Infecciones por VIH/transmisión , VIH-1 , Humanos , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , KeniaRESUMEN
This study assessed maternal genital colonization and subsequent neonatal transmission rate of Ureaplasma urealyticum in pregnant women in an average socioeconomic population. In addition very low birth weight infants were assessed to determine whether the presence of U. urealyticum correlated with increased risk of developing respiratory problems. The study group consisted of 108 sequential full term mothers and 104 preterm mothers delivering in a tertiary care hospital in central Canada. The genital carriage rates (assessed using placental sampling) of ureaplasmas in term and preterm mothers were 25.9 and 19.2%, respectively (P = 0.3185). Acquisition of ureaplasmas in the neonatal respiratory tract of neonates occurred significantly (P = 0.0182) more often in preterm neonates (11 of 130; 8.5%) than in term neonates (2 of 110; 0.9%). Very low birth weight (VLBW) infants (< or = 1500 g) were at greater risk (P = 0.042) of acquiring ureaplasmas in their respiratory tracts (5 of 26; 19%) than larger preterm neonates (6 of 104; 5.8%). All VLBW infants with respiratory colonization by ureaplasmas (5 of 5) developed bronchopulmonary dysplasia compared with 33% (7 of 21) of VLBW neonates without ureaplasmas (P = 0.028). This difference in bronchopulmonary dysplasia development among VLBW infants was independent of further stratification by birth weight. These VLBW neonates with ureaplasmas also stayed significantly (P = 0.037) longer in the neonatal intensive care unit (43.6 +/- 10.4 days) than did other preterm neonates (22.1 +/- 20.8 days). Our results demonstrate that VLBW preterm neonates have increased risk of acquiring U. urealyticum.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Displasia Broncopulmonar/etiología , Enfermedades del Prematuro/etiología , Transmisión Vertical de Enfermedad Infecciosa , Complicaciones Infecciosas del Embarazo , Infecciones por Ureaplasma/transmisión , Ureaplasma urealyticum/aislamiento & purificación , Adulto , Displasia Broncopulmonar/epidemiología , Recuento de Colonia Microbiana , Femenino , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/epidemiología , Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Masculino , Embarazo , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/epidemiología , Factores de Riesgo , Factores Socioeconómicos , Infecciones por Ureaplasma/diagnóstico , Infecciones por Ureaplasma/epidemiologíaRESUMEN
A malformation syndrome has been proposed in infants with acquired immunodeficiency syndrome or acquired immunodeficiency syndrome-related complex secondary to congenital infection with human immunodeficiency virus (HIV) in the United States and Europe. To determine whether embryopathy is detectable in HIV-exposed African infants, 85 infants of HIV-seropositive mothers and 98 infants of HIV-seronegative mothers in Nairobi, Kenya, were examined for minor and major anomalous features shortly after birth. No mother used intravenous drugs. With the exception of growth failure no anomalous feature was associated with in utero HIV exposure. No increase in the number of anomalous features per infant was correlated with HIV, nor did any infant have the reported malformation syndrome. Thus in this population of African infants examination for anomalous features during the neonatal period failed to identify those infants with fetal exposure to HIV.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Anomalías Congénitas/etiología , Seropositividad para VIH , Complicaciones Infecciosas del Embarazo , Adolescente , Adulto , Estudios de Cohortes , Femenino , Trastornos del Crecimiento/etiología , Humanos , Lactante , Recién Nacido , Kenia , Masculino , Embarazo , Estudios ProspectivosRESUMEN
OBJECTIVES: To compare pneumococcal nasopharyngeal colonization rates among HIV-1-infected children with those of uninfected children born to seropositive mothers and those of seronegative controls. To determine the predominant serotypes and antimicrobial susceptibility among pneumococcal isolates in Kenya. METHODS: Nasopharyngeal pneumococcal colonization was examined in 207 children recruited from the Perinatal HIV-1 Transmission Study conducted in Nairobi, Kenya. Colonization was compared among HIV-1-infected children, uninfected children born to seropositive mothers and control seronegative children. Isolates were serotyped and tested for antibiotic susceptibility to penicillin, tetracycline, erythromycin, chloramphenicol, clindamycin and rifampin. RESULTS: Colonization was higher among HIV-1-infected and uninfected children than among controls only when associated with respiratory illnesses (86% of 7 and 60% of 20 vs. 29% of 31, P = 0.004). No differences were observed when children were asymptomatic (20% of 35, 35% of 94 and 22% of 101). Intermediate penicillin resistance was found in 60% of 94 isolates, 28% were resistant to tetracycline and all isolates were susceptible to the other antibiotics tested. Sixteen serotypes were identified, with 13, 15, 14, 6B and 19F comprising 73% of isolates. Serotype 13 was found in 31% of colonized children. This serotype and 2 others isolated are not found in the current 23-valent polysaccharide vaccine. Overall 41% of colonized children harbored nonvaccine strains. CONCLUSIONS: Although nasopharyngeal pneumococcal colonization was high among children with respiratory illness born to HIV-1-seropositive mothers, increased asymptomatic colonization did not explain the increased risk of invasive pneumococcal disease associated with HIV-1 infection. Intermediate penicillin resistance was common but high level penicillin and multiple antibiotic resistance were not seen. The prevalence of the unique strains circulating in this region will need to be considered in the design of effective pneumococcal vaccines for use in East Africa.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/microbiología , VIH-1 , Nasofaringe/microbiología , Streptococcus pneumoniae/aislamiento & purificación , Farmacorresistencia Microbiana , Femenino , Humanos , Lactante , Masculino , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/efectos de los fármacosRESUMEN
Although prevalence of M. hominis colonization during pregnancy varies from 12-50%, its role in infections of the mother and newborn infants is unclear. Definite correlations exist with chorioamnionitis and amniotic fluid infections, but as it is rarely isolated alone during these infections, its pathogenic role is uncertain. Its association with septic abortion is similarly questioned. Prevalence and antibody titers to M. hominis increase with increasing parity. Transient bacteremia occurs in approximately 2.5% of normal deliveries. M. hominis does have a significant role in postpartum fever. Women harboring the organism during labor with low predelivery antibody titers are at risk. Approximately 30% of exposed infants are colonized (4% of all infants) but there are only a few reports of neonatal meningitis, pneumonia, or skin abscesses due to M. hominis. Most recover without specific therapy. The role of antimicrobial therapy of M. hominis in pregnancy and the neonatal period is unclear. Further studies of these issues should simultaneously consider all potential genital tract pathogens.