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OBJECTIVES: To describe the epidemiology of Klebsiella spp. meningitis in France with respect to clinical and bacteriological data. METHODS: We performed a four-year multicenter, retrospective, observational study. The primary objective was to provide a clinical description of patients with Klebsiella spp. meningitis. Secondary objectives were to compare community-acquired meningitis and healthcare-associated meningitis and to analyze factors associated with mortality. RESULTS: We enrolled 131 patients with Klebsiella spp. meningitis. Eighty-two (62.6%) infections were reported following neurosurgery. Twenty-eight strains (21.4%) were resistant to third-generation cephalosporins (3GC). The median [IQR] cellularity was 980/mm3 [116-5550], the median protein level was 5.67 [1.62-9] g/L and the median CSF glucose level was 2.5 [0-3.4] mmol/L. The in-hospital mortality rate was 23.6%. Community-acquired meningitis isolates were more frequently susceptible to 3GC than isolates from healthcare-associated meningitis (89.2% versus 72%; P=0.04). Comorbidities reported for patients with community-acquired meningitis were mainly diabetes mellitus and liver cirrhosis. In multivariate analysis, focal neurological disorder at the time of diagnosis was the only factor associated with in-hospital mortality (P=0.01). CONCLUSIONS: Purulent meningitis caused by Klebsiella spp. needs to be considered in patients with community-acquired meningitis and preexisting conditions, as well as in case of meningitis following neurosurgical procedures.
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Infecciones por Klebsiella , Meningitis Bacterianas , Francia/epidemiología , Humanos , Klebsiella , Infecciones por Klebsiella/complicaciones , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/epidemiología , Meningitis Bacterianas/complicaciones , Meningitis Bacterianas/tratamiento farmacológico , Meningitis Bacterianas/epidemiología , Estudios RetrospectivosRESUMEN
BACKGROUND: Stenotrophomonas maltophilia is an emerging opportunistic pathogen. The increasing incidence is of particular concern in patients with cystic fibrosis (CF). Since 2012, the Western France has witnessed high annual prevalence of S. maltophilia colonization/infection. This retrospective cohort study investigated the epidemiology of S. maltophilia emergence in the CF center of Roscoff, Western France, a region of high prevalence of CF in Europe. METHODS: All CF patients with S. maltophilia isolated in respiratory samples between December 2013 and February 2017 were included. For each patient the colonization status with S. maltophilia was determined. The epidemiological and microbiological characteristics collected were compared between colonization statuses. RESULTS: S. maltophilia was isolated in 90 patients (42 males, 48 females). Mean age at first colonization was 24.4±13.5 years. Annual prevalence since 2013 was high (16-17.9%), but stable. This high prevalence is mainly due to a high rate of intermittent colonization. Only 2.8% of CF patients showed chronic colonization, with significantly more frequent co-colonization by methicillin-susceptible Staphylococcus aureus (P<0.0001) and Pseudomonas aeruginosa (P<0.05). During chronic colonization, S. maltophilia acquired resistance to cotrimoxazole and ß-lactams. Interestingly, there were cases of decolonization. CONCLUSION: This is the first epidemiological report of S. maltophilia in a French CF center. Prevalence was stable but above the national average. Most cases were intermittent; chronic colonization was rare.
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Fibrosis Quística/epidemiología , Infecciones por Bacterias Gramnegativas/epidemiología , Stenotrophomonas maltophilia , Adolescente , Adulto , Niño , Estudios de Cohortes , Fibrosis Quística/complicaciones , Fibrosis Quística/microbiología , Femenino , Francia/epidemiología , Infecciones por Bacterias Gramnegativas/complicaciones , Humanos , Masculino , Prevalencia , Infecciones del Sistema Respiratorio/complicaciones , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/microbiología , Estudios Retrospectivos , Stenotrophomonas maltophilia/aislamiento & purificación , Adulto JovenRESUMEN
This article, written by a collective of international researchers and worldwide representatives of indigenous populations, is an open letter to the WHO, based on the latest elements from the scientific literature, and the latest climatological data. It takes stock of the health consequences of global warming, and urges research organizations to take an interest in infectious agents formerly stored in the layers of ground (frozen or not) and now mobilized, then released from a distance.
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Salud Global , Calentamiento Global , Pueblos Indígenas , Microbiología del Suelo , Cadáver , Epidemias , Humanos , Hielos Perennes , Organización Mundial de la SaludRESUMEN
BACKGROUND: A variety of microorganisms can cause infective endocarditis (IE), with Staphylococci and Streptococci accounting for the majority of cases. Streptococci are a common cause of community-acquired IE but few studies have focused on this subgroup of endocarditis. METHODS: A retrospective multicentre study was conducted between 2012 and 2017 in 12 hospital centres in France. Data were extracted from the local diagnosis-related group database and matched with microbiological results. After identification, the records were retrospectively analysed. RESULTS: A total of 414 patients with streptococcal endocarditis were included. The patients were predominantly male (72.8%) and the median age was 73.2 years (interquartile range [IQR] 61.3-80.9). The majority of patients (70.6%) had native valve endocarditis. Embolic complications were seen in 38.8% of patients. Viridans group Streptococci (VGS) and bovis-equinus group Streptococci (BGS) accounted for 52.4% and 34.5% of isolated strains, respectively. Minimum inhibitory concentrations (MICs) of amoxicillin were <0.125, 0.125-2 and >2 mg/L for 59.6%, 27% and 1% of isolates, respectively. In-hospital mortality for patients with Streptococci-related IE was 17.8%. In multivariate analysis, the only factor associated with in-hospital mortality was MIC for amoxicillin between 0.25 and 2 mg/L (P = 0.04; OR = 2.23 [95% confidence interval (CI) 1.03-4.88]) whereas performance of cardiac surgery for IE was a protective factor (P = 0.001, OR = 0.23 [95% CI 0.1-0.56]). CONCLUSIONS: IE remains a serious and deadly disease despite recent advances in diagnosis and treatment. Adaptation of antibiotic doses to MICs for amoxicillin and surgery may improve patient outcome.
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Amoxicilina/farmacología , Antibacterianos/farmacología , Endocarditis/microbiología , Infecciones Estreptocócicas/microbiología , Streptococcus/efectos de los fármacos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Endocarditis/epidemiología , Endocarditis/mortalidad , Femenino , Francia/epidemiología , Hospitales , Humanos , Masculino , Pruebas de Sensibilidad Microbiana/métodos , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/mortalidad , Streptococcus/clasificación , Streptococcus/aislamiento & purificación , Análisis de Supervivencia , Adulto JovenAsunto(s)
Infecciones por Helicobacter/diagnóstico , Helicobacter/aislamiento & purificación , Enfermedad de Raynaud/microbiología , Adulto , Antibacterianos/uso terapéutico , Femenino , Helicobacter/efectos de los fármacos , Infecciones por Helicobacter/tratamiento farmacológico , Humanos , Inmunocompetencia , Enfermedad de Raynaud/complicaciones , Resultado del TratamientoAsunto(s)
Capnocytophaga , Infecciones por Bacterias Gramnegativas , Meningitis Bacterianas/microbiología , Infecciones por Bacterias Gramnegativas/diagnóstico , Infecciones por Bacterias Gramnegativas/terapia , Humanos , Masculino , Meningitis Bacterianas/diagnóstico , Meningitis Bacterianas/terapia , Persona de Mediana EdadRESUMEN
BACKGROUND: The implementation of MALDI-TOF MS for microorganism identification has changed the routine of the microbiology laboratories as we knew it. Most microorganisms can now be reliably identified within minutes using this inexpensive, user-friendly methodology. However, its application in the identification of mycobacteria isolates has been hampered by the structure of their cell wall. Improvements in the sample processing method and in the available database have proved key factors for the rapid and reliable identification of non-tuberculous mycobacteria isolates using MALDI-TOF MS. AIMS: The main objective is to provide information about the proceedings for the identification of non-tuberculous isolates using MALDI-TOF MS and to review different sample processing methods, available databases, and the interpretation of the results. SOURCES: Results from relevant studies on the use of the available MALDI-TOF MS instruments, the implementation of innovative sample processing methods, or the implementation of improved databases are discussed. CONTENT: Insight about the methodology required for reliable identification of non-tuberculous mycobacteria and its implementation in the microbiology laboratory routine is provided. IMPLICATIONS: Microbiology laboratories where MALDI-TOF MS is available can benefit from its capacity to identify most clinically interesting non-tuberculous mycobacteria in a rapid, reliable, and inexpensive manner.
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Micobacterias no Tuberculosas/aislamiento & purificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Técnicas Bacteriológicas , Humanos , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Flujo de TrabajoRESUMEN
OBJECTIVES: Prosthetic joint infections (PJI) are responsible for significant morbidity and mortality and their number continues to rise. Their management remains complex, especially the microbiological diagnosis. Besides 'homemade' tests developed by several teams, new molecular biology methods are now available with different analytical performance and usability. METHODS: We studied the performances of one of these tests: ITI® multiplex PCR (mPCR) by the Curetis® company and compared it to either 'optimized' culture or 16S rRNA PCR. We performed a retrospective multicentre study to assess the contributions of mPCR in the diagnosis of PJI. We randomly selected 484 intraoperative specimens among 1252 of various types (biopsy, bone, tissue around the prosthesis, synovial fluid) from 251 patients in seven different hospitals. Each sample was treated according to the recommendations of the manufacturer. RESULTS: In all, 154 out of 164 (93.9%) samples negative in culture were negative with the mPCR. Among the 276 positive samples in culture, 251 (90.9%) were monomicrobial, of which 119 (47.4%) were positive with the mPCR, and 25 (9.1%) were polymicrobial, of which 12 (48%) were positive with the mPCR. The concordance rate of mPCR with culture was 58.1% (53.6%-62.7%) and the concordance rate with 16S rRNA PCR was 70.1% (65.5%-74.6%). CONCLUSION: This new standardized molecular test showed a lack of detection when the bacterial inoculum was low (number of positive media per sample and number of colonies per media) but can be useful when patients have received antibiotic therapy previously.
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Prótesis Articulares/microbiología , Staphylococcus aureus Resistente a Meticilina/genética , Reacción en Cadena de la Polimerasa Multiplex/métodos , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Estafilocócicas/diagnóstico , Proteínas Bacterianas/genética , Humanos , Resistencia a la Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Proteínas de Unión a las Penicilinas/genética , Infecciones Relacionadas con Prótesis/mortalidad , ARN Ribosómico 16S/genética , Estudios Retrospectivos , Infecciones Estafilocócicas/microbiologíaAsunto(s)
Absceso Pulmonar/microbiología , Infecciones por Pasteurellaceae/microbiología , Pasteurellaceae/aislamiento & purificación , Anciano , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Técnicas de Tipificación Bacteriana , Coinfección/tratamiento farmacológico , Coinfección/microbiología , Comorbilidad , Infecciones por Escherichia coli/complicaciones , Infecciones por Escherichia coli/tratamiento farmacológico , Humanos , Absceso Pulmonar/tratamiento farmacológico , Masculino , Desnutrición/complicaciones , Desnutrición/terapia , Nutrición Parenteral , Infecciones por Pasteurellaceae/complicaciones , Infecciones por Pasteurellaceae/tratamiento farmacológico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
OBJECTIVES: Early detection of Pseudomonas aeruginosa lung positivity is a key element in cystic fibrosis (CF) management. PCR has increased the accuracy of detection of many microorganisms. Clinical relevance of P. aeruginosa quantitative PCR (qPCR) in this context is unclear. Our aim was to determine P. aeruginosa qPCR sensitivity and specificity, and to assess the possible time saved by qPCR in comparison with standard practice (culture). METHODS: A multicentre cohort study was conducted over a 3-year period in 96 patients with CF without chronic P. aeruginosa colonization. Sputum samples were collected at each visit. Conventional culture and two-step qPCR (oprL qPCR and gyrB/ecfX qPCR) were performed for 707 samples. The positivity criteria were based on the qPCR results, defined in a previous study as follow: oprL qPCR positivity alone if bacterial density was <730 CFU/mL or oprL qPCR combined with gyrB/ecfX qPCR if bacterial density was ≥730 CFU/mL. RESULTS: During follow up, 36 of the 96 patients with CF were diagnosed on culture as colonized with P. aeruginosa. This two-step qPCR displayed a sensitivity of 94.3% (95% CI 79.7%-98.6%), and a specificity of 86.3% (95% CI 83.4%-88.7%). It enabled P. aeruginosa acquisition to be diagnosed earlier in 20 patients, providing a median detection time gain of 8 months (interquartile range 3.7-17.6) for them. CONCLUSIONS: Implementing oprL and gyrB/ecfX qPCR in the management of patients with CF allowed earlier detection of first P. aeruginosa lung positivity than culture alone.
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Fibrosis Quística/complicaciones , Diagnóstico Precoz , Técnicas de Diagnóstico Molecular/métodos , Infecciones por Pseudomonas/diagnóstico , Pseudomonas aeruginosa/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Adolescente , Técnicas Bacteriológicas/métodos , Niño , Femenino , Humanos , Masculino , Estudios Prospectivos , Sensibilidad y Especificidad , Esputo/microbiología , Factores de TiempoRESUMEN
INTRODUCTION: Infection with Mycobacterium abscessus sensu lato is uncommon in patients without cystic fibrosis. We are interested in these patients and have collected cases in Finistère between 2007 and 2011. CASE REPORTS: Four patients met the infection criteria recommended by the American Thoracic Society in 2007. Among them, all had Aspergillus spp. in sputum, 3 had gastroesophageal reflux and two had the criteria for allergic bronchopulmonary aspergillosis. We identified Mycobacterium massiliense in the single patient in our series whose therapeutic outcome was successful. CONCLUSION: By comparing these data with those in the literature, we believe that the search for allergic bronchopulmonary aspergillosis and gastroesophageal reflux is necessary in these patients and that species identification is essential for prognosis.
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Infecciones por Mycobacterium no Tuberculosas/microbiología , Micobacterias no Tuberculosas/aislamiento & purificación , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Aspergilosis Broncopulmonar Alérgica/complicaciones , Aspergilosis Broncopulmonar Alérgica/tratamiento farmacológico , Aspergilosis Broncopulmonar Alérgica/microbiología , Resultado Fatal , Femenino , Humanos , Masculino , Infecciones por Mycobacterium no Tuberculosas/complicaciones , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Insuficiencia Respiratoria/tratamiento farmacológico , Insuficiencia Respiratoria/microbiologíaRESUMEN
Bacterial infections are uncommon complications of the blood products transfusion but they are potentially serious. Many advances have been done over the past few years to guarantee the microbiological security of blood products as the donors selection with a medical talk, the derivation of the first 30 millilitres blood during the donation, the deleucocytation of blood products But in spite of these advances, cases of bacterial infection always remain. The purpose of this study was to point out the platelet concentrate's transfusion-transmitted bacterial infection with Streptococcus gallolyticus and the unusual consequence for the donor by uncovering an asymptomatic rectal neoplastic tumor. This study as raised as to whether the usefulness of systematic bacterial inactivation in the platelets concentrates.
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Bacteriemia/transmisión , Transfusión de Plaquetas/efectos adversos , Infecciones Estreptocócicas/transmisión , Streptococcus/aislamiento & purificación , Adenocarcinoma/complicaciones , Adenocarcinoma/diagnóstico , Anciano de 80 o más Años , Enfermedades Asintomáticas , Bacteriemia/complicaciones , Bacteriemia/microbiología , Donantes de Sangre , Seguridad de la Sangre , Escalofríos/etiología , ADN Bacteriano/sangre , Transfusión de Eritrocitos , Femenino , Fiebre/etiología , Humanos , Hallazgos Incidentales , Leucemia Mieloide Aguda/terapia , Plaquetoferesis , Neoplasias del Recto/complicaciones , Neoplasias del Recto/diagnóstico , Infecciones Estreptocócicas/complicaciones , Infecciones Estreptocócicas/microbiología , Streptococcus/genéticaRESUMEN
Antibiotics, of which Fleming has identified the first representative, penicillin, in 1928, allowed dramatical improvement of the treatment of patients presenting with infectious diseases. However, once an antibiotic is used, resistance may develop more or less rapidly in some bacteria. It is thus necessary to develop therapeutic alternatives, such as the use of probiotics, defined by the World Health Organization (WHO) as "micro-organisms which, administered live and in adequate amounts, confer a benefit to the health of the host". The scope of these micro-organisms is broad, concerning many areas including that of infectious diseases, especially respiratory infections. We describe the rational use of probiotics in respiratory tract infections and detail the results of various clinical studies describing the use of probiotics in the management of respiratory infections such as nosocomial or community acquired pneumonia, or on specific grounds such as cystic fibrosis. The results are sometimes contradictory, but the therapeutic potential of probiotics seems promising. Implementing research to understand their mechanisms of action is critical to conduct therapeutic tests based on a specific rational for the strains to be used, the dose, as well as the chosen mode and rhythm of administration.
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Neumonía Bacteriana/terapia , Probióticos/uso terapéutico , Animales , Infecciones Comunitarias Adquiridas/microbiología , Infecciones Comunitarias Adquiridas/terapia , Infección Hospitalaria/microbiología , Infección Hospitalaria/terapia , Fibrosis Quística/complicaciones , Susceptibilidad a Enfermedades , Método Doble Ciego , Humanos , Sistema Inmunológico/inmunología , Ratones , Microbiota , Neumonía Bacteriana/microbiología , Neumonía Asociada al Ventilador/microbiología , Neumonía Asociada al Ventilador/fisiopatología , Neumonía Asociada al Ventilador/terapia , Probióticos/efectos adversos , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Percepción de Quorum , Ensayos Clínicos Controlados Aleatorios como Asunto , Sistema Respiratorio/microbiología , Especificidad de la EspecieRESUMEN
Shewanella putrefaciens is rarely involved in human infectious disease. We report here a case of soft tissue infection with bacteremia on a patient with risk factors (liver cirrhosis, diabetes mellitus).
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Bacteriemia/etiología , Infecciones por Bacterias Gramnegativas/complicaciones , Shewanella putrefaciens/fisiología , Infecciones de los Tejidos Blandos/etiología , Anciano , Bacteriemia/diagnóstico , Complicaciones de la Diabetes/etiología , Complicaciones de la Diabetes/microbiología , Infecciones por Bacterias Gramnegativas/diagnóstico , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/microbiología , Masculino , Shewanella putrefaciens/aislamiento & purificación , Infecciones de los Tejidos Blandos/diagnósticoRESUMEN
OBJECTIVES: International adoption from developing countries has become an increasing phenomenon in recent years. Given the high prevalence of multidrug-resistant (MDR) bacteria in these countries, the adopted children represent a group at risk for both carriage and infection with MDR bacteria. The dynamics of intrafamilial transmission of MDR bacteria after adoption was studied in a prospective study from January 2002 to January 2005. METHODS: Stool samples, taken at the first visit to the outpatient adoption practice and subsequently every month, from the adopted children of an orphanage of Bamako (Mali) and from all the members of their adoptive families were screened for MDR bacteria and bacterial pathogens. Bacteria were characterized by standard biochemical methods, disc diffusion antibiograms, PFGE and plasmid analysis. beta-Lactamase genes were sought by PCR. RESULTS: Over the study period, 52 ESBL-producing Enterobacteriaceae (E-ESBL), with Escherichia coli (56%) being the most prevalent, were isolated from 24/25 adoptees at arrival in France. During follow-up, the transmission of ESBL-producing E. coli and Salmonella enterica Babelsberg between the adoptees and their adoptive family members has clearly been demonstrated for 5/22 families (23%). The mean duration of the carriage for the adopted children was 9 months (1-15 months). CTX-M-15 was the most prevalent resistance gene among the E-ESBLs (93%), while SHV-12 was found among the S. enterica Babelsberg studied. CONCLUSIONS: International travellers, transfer of patients and now adoption may contribute to the global emergence of MDR bacteria. Thus, in addition to the usual screening of adopted children for infectious diseases, additional screening for MDR bacteria should be recommended, at least for children coming from countries with a high prevalence of MDR bacteria.
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Adopción , Infecciones por Escherichia coli/transmisión , Escherichia coli/enzimología , Salud de la Familia , Infecciones por Salmonella/transmisión , Salmonella enterica/enzimología , beta-Lactamasas/biosíntesis , Técnicas de Tipificación Bacteriana , Portador Sano/microbiología , Portador Sano/transmisión , Niño , Preescolar , Análisis por Conglomerados , Dermatoglifia del ADN , Farmacorresistencia Bacteriana Múltiple , Electroforesis en Gel de Campo Pulsado , Escherichia coli/clasificación , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Heces/microbiología , Femenino , Francia , Genotipo , Humanos , Masculino , Malí , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Plásmidos/análisis , Infecciones por Salmonella/microbiología , Salmonella enterica/clasificación , Salmonella enterica/genética , Salmonella enterica/aislamiento & purificaciónRESUMEN
Congenital tuberculosis (TB) remains a rare disease but is fatal if untreated. Early detection is difficult because of the non-specific nature of the symptoms in TB during pregnancy and infancy. This report summarizes a case of congenital TB in a very premature infant, born at 25 weeks gestation. Miliary TB was diagnosed in the mother when the neonate was 20 days old. Antituberculous therapy allowed a rapid improvement in the mother. The infant died at 27 days old. A Beijing genotype strain of Mycobacterium tuberculosis was isolated both in the mother, from pulmonary and urine specimens, and in the infant, from peritoneal fluid.
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Líquido Ascítico/microbiología , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis/diagnóstico , Tuberculosis/microbiología , Adulto , Antituberculosos/uso terapéutico , Resultado Fatal , Femenino , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Embarazo , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Nacimiento Prematuro , Esputo/microbiología , Tuberculosis/transmisión , Orina/microbiologíaRESUMEN
Presented here are two cases of systemic Candida glabrata infection diagnosed in two expectant mothers and their fetuses at 34 and 22 weeks' gestation. The underlying risk factors in case 1 were in vitro fertilization and embryo transfer, recurrent yeast vaginitis and two intravenous injections of betamethasone. The risk factors in case 2 were in vitro fertilization and embryo transfer, recurrent yeast vaginitis, antibiotics for treatment of a urinary tract infection due to Morganella morganii and amniocentesis. In both cases, vaginal fluid yielded growth of a yeast that was not identified. Candida glabrata was isolated from samples obtained from the mothers and their babies. Since Candida glabrata lacks hyphae, membranitis and infection of the fetuses were demonstrated only on slides stained with Gomori Grocott and periodic acid-Schiff. Both cases suggest that for such pregnancies the follow-up of vaginal fluid should include the identification of any yeasts grown on selective Candida medium. In case of premature rupture of membranes, systematic sampling of mothers and their infants or fetuses should be associated with microscopic study of placentas, membranes and stillborn fetuses with Gomori Grocott and periodic acid-Schiff staining techniques.