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PURPOSE: The spectrum of causative organisms in infective endocarditis (IE) has changed significantly in the last decades. Reliable pathogen detection is crucial for appropriate antimicrobial therapy for IE. The aim of the study was to evaluate the diagnostic value of microbiological methods for detecting the causative microorganism of IE and to analyze the spectrum of pathogens. METHODS: A total of 224 cases (211 unique patients, some with multiple surgeries) were included into this retrospective study. Patients were diagnosed with IE according to the modified Duke criteria from January 2016 to July 2021 and underwent heart valve surgery in a tertiary hospital. Pathogen detection was performed by blood culture, microbiological culture and 16S rDNA PCR of explanted heart valve material. RESULTS: A causative pathogen of IE was detected in 95.5% (n = 214) of cases. Blood cultures were positive in 83.3%, while a pathogen in the examined heart valve samples was identified in 32.6% by culture and in 88.2% by 16S rDNA PCR. A microorganism was identified by 16S rDNA PCR in 61.1% of blood culture negative cases but only in 19.4% by heart valve culture. The most common pathogens were Staphylococcus aureus (27%), viridans group streptococci (20%), enterococci (19%) and coagulase-negative staphylococci (CoNS 8%). Cutibacterium acnes (7%) was detected in prosthetic valve IE cases only. CONCLUSION: Blood culture as a comparatively non-invasive and straightforward technique remains an important and reliable method for initial detection of the causative organism in IE. Diagnostic stewardship programs should broadly emphasize proper collection of blood cultures, particularly sampling prior to any antibiotic treatment. Additionally, molecular testing using 16S rDNA tissue PCR can be used with culture techniques to increase the diagnostic yield, especially in the case of a negative blood culture.
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Endocarditis Bacteriana , Endocarditis , Humanos , Estudios Retrospectivos , Bacterias/genética , ARN Ribosómico 16S/genética , Endocarditis Bacteriana/diagnóstico , Endocarditis Bacteriana/tratamiento farmacológico , Endocarditis Bacteriana/microbiología , Endocarditis/diagnóstico , Endocarditis/cirugía , Endocarditis/microbiología , ADN Ribosómico/genéticaRESUMEN
Quantitative PCR (qPCR) assays are the gold standard for diagnosis of Pneumocystis jirovecii pneumonia (PCP). However, they are laborious and require skilled personnel. Therefore, execution outside regular working hours of the molecular biology laboratory is limited. The eazyplex P. jirovecii assay (PJA) uses loop-mediated isothermal amplification for detection of P. jirovecii It is performed directly with respiratory specimens, without the need for special skills, and delivers a result within 3 to 25 min. The goal of our study was to compare the performance of the eazyplex PJA with that of established P. jirovecii qPCR assays. All archived bronchoalveolar lavage fluid (BALF) samples that had previously tested positive for P. jirovecii by qPCR assay and 50 control samples (retrospective part), as well as all BALF samples received for P. jirovecii analysis over a period of 4 months (prospective part), were tested. Forty-nine patients with proven PCP and 126 patients without PCP were included. The sensitivity and specificity of the eazyplex PJA (95.7% and 96.5%, respectively) were comparable to those for three different P. jirovecii qPCR assays. The detection limit of the eazyplex PJA was analogous to 103 copies of the major surface glycoprotein gene per 25 µl of BALF, corresponding to 10 to 20 P. jirovecii cells. The eazyplex PJA reliably discriminated patients with PCP from patients with P. jirovecii colonization. It delivered a positive result within a mean of 9 min 38 s and required a hands-on time of 2 min 45 s. In summary, the eazyplex PJA showed identical performance for the diagnosis of PCP, compared to qPCR assays. However, in terms of time to result, practicability, and robustness, the eazyplex PJA is clearly superior and allows for around-the-clock molecular testing.
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Pneumocystis carinii , Neumonía por Pneumocystis , Líquido del Lavado Bronquioalveolar , Humanos , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Pneumocystis carinii/genética , Neumonía por Pneumocystis/diagnóstico , Estudios Prospectivos , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
The genus Corynebacterium includes species of biotechnological, medical and veterinary importance. An atypical C. ulcerans strain, W25, was recently isolated from a case of necrotizing lymphadenitis in a wild boar. In this study, we have analysed the genome sequence of this strain and compared the phenotypic and virulence properties with other corynebacterial pathogens. Phylogenomic analyses revealed that strain W25 belongs to a novel species along with PO100/5 and KL1196. The latter strains were isolated from a pig and a roe deer, respectively; hence, this species appears to be associated to animals. The isolate W25 is likely a non-toxigenic tox gene bearing strain and may have compromised abilities to adhere to pharyngeal and laryngeal epithelial cells due to potential loss of the gene functions in spaBC and spaDEF pilus gene clusters. A number of corynebacterial virulence genes are present including pld encoding phospholipase D. Therefore, this strain may be able to cause severe invasive infections in animals and zoonotic infections in humans.
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Infecciones por Corynebacterium/microbiología , Infecciones por Corynebacterium/veterinaria , Corynebacterium/clasificación , Corynebacterium/aislamiento & purificación , Filogenia , Animales , Toxinas Bacterianas/genética , Corynebacterium/genética , Corynebacterium/patogenicidad , Ciervos , Fimbrias Bacterianas/genética , Genoma Bacteriano , Humanos , Familia de Multigenes , Porcinos , Virulencia/genética , Factores de Virulencia/genética , Zoonosis/microbiologíaRESUMEN
Boron-doped diamond electrodes can be used to generate reactive oxygen species directly at the electrode's surface. This property was used in this study for in-situ electrochemical oxidation to eliminate different bacteria, i.e. Escherichia coli, Pseudomonas fluorescens and Pseudomonas aeruginosa, as well as Bacillus subtilis spores from water samples. Application of low voltages in the rage from 4 to 10 V and short incubation times in the range of minutes allowed a complete disinfection of water contaminated with enterobacteria and freshwater microbes including nosocomial pathogens as well as a significant reduction of spores. A pilot reactor was constructed, which allowed to decrease microbial contamination of sewage plant effluent drastically. Boron-doped diamond electrodes allow efficient reduction of bacterial contaminations in water samples.
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Boro/química , Diamante/química , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Electrodos , Microbiología del Agua , Purificación del Agua/instrumentación , Purificación del Agua/métodos , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/crecimiento & desarrollo , Desinfección/instrumentación , Desinfección/métodos , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Agua Dulce/microbiología , Oxidación-Reducción , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/crecimiento & desarrollo , Pseudomonas fluorescens/efectos de los fármacos , Pseudomonas fluorescens/crecimiento & desarrollo , Especies Reactivas de Oxígeno/metabolismo , Especies Reactivas de Oxígeno/farmacología , Aguas del Alcantarillado , Esporas Bacterianas/efectos de los fármacos , Esporas Bacterianas/crecimiento & desarrollo , Contaminantes del AguaRESUMEN
Nucleic acid amplification techniques (NATs), such as PCR, are highly sensitive and specific methods that have become valuable supplements to culture and serology in the diagnosis of infectious disorders. However, especially when using formalin-fixed and paraffin-embedded tissue, these techniques are associated with both false-negative and false-positive results, a pitfall that is frequently misjudged. Representatives of the German Society of Hygiene and Microbiology (DGHM) and the German Society of Dermatology (DDG) therefore set out to develop a consensus - in the form of a review article - on the appropriate indications for NATs using paraffin-embedded tissue, its contraindications, and the key points to be considered in the pre- and post-analytical phase. Given that fresh, naive tissue is preferably to be used in the workup of a suspected infection, PCR analysis on paraffin sections represents an exception. The latter may be considered if an infection is suspected at a later point in time and fresh tissue has not been preserved or can no longer be obtained. Potential indications include confirmation of histologically suspected infections with Leishmania spp., Bartonella spp., Rickettsia spp., or in case of ecthyma contagiosum. Infections with, for example, mycobacteria or RNA viruses, on the other hand, are not considered useful indications for NATs using paraffin sections. In order to avoid misinterpretation of test results, it is essential that laboratory reports on NATs using paraffin-embedded tissue contain information on the indication/diagnostic circumstances, the required and chosen pre-analytical steps, the limitations of the method, and on diagnostic alternatives.
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Técnicas de Amplificación de Ácido Nucleico/métodos , Adhesión en Parafina , Enfermedades Cutáneas Infecciosas/diagnóstico , Bartonella/genética , Infecciones por Bartonella/diagnóstico , Ectima Contagioso/diagnóstico , Humanos , Leishmania/genética , Leishmaniasis Cutánea/diagnóstico , Técnicas de Diagnóstico Molecular , Virus del Orf/genética , Rickettsia/genética , Fiebre Maculosa de las Montañas Rocosas/diagnóstico , Enfermedades Cutáneas Infecciosas/microbiologíaRESUMEN
Nukleinsäure-Amplifikations-Techniken (NAT), wie die PCR, sind hochsensitiv sowie selektiv und stellen in der mikrobiologischen Diagnostik wertvolle Ergänzungen zur kulturellen Anzucht und Serologie dar. Sie bergen aber gerade bei formalinfixiertem und in Paraffin eingebettetem Gewebe ein Risiko für sowohl falsch negative als auch falsch positive Resultate, welches nicht immer richtig eingeschätzt wird. Daher haben Vertreter der Deutschen Gesellschaft für Hygiene und Mikrobiologie (DGHM) und der Deutschen Dermatologischen Gesellschaft (DDG) einen Konsensus in Form einer Übersichtsarbeit erarbeitet, wann eine NAT am Paraffinschnitt angezeigt und sinnvoll ist und welche Punkte dabei in der Präanalytik und Befundinterpretation beachtet werden müssen. Da bei Verdacht auf eine Infektion grundsätzlich Nativgewebe genutzt werden soll, ist die PCR am Paraffinschnitt ein Sonderfall, wenn beispielsweise bei erst nachträglichaufgekommenem Verdacht auf eine Infektion kein Nativmaterial zur Verfügung steht und nicht mehr gewonnen werden kann. Mögliche Indikationen sind der histologisch erhobene Verdacht auf eine Leishmaniose, eine Infektion durch Bartonellen oder Rickettsien, oder ein Ecthyma contagiosum. Nicht sinnvoll ist oder kritisch gesehen wird eine NAT am Paraffinschnitt zum Beispiel bei Infektionen mit Mykobakterien oder RNA-Viren. Die Konstellation für eine NAT aus Paraffingewebe sollte jeweils benannt werden, die erforderliche Prä-Analytik, die jeweiligen Grenzen des Verfahrens und die diagnostischen Alternativen bekannt sein. Der PCR-Befund sollte entsprechend kommentiert werden, um Fehleinschätzungen zu vermeiden.
RESUMEN
Human guanylate binding protein-1 (GBP-1) belongs to the family of large GTPases. The expression of GBP-1 is inducible by inflammatory cytokines, and the protein is involved in inflammatory processes and host defence against cellular pathogens. GBP-1 is the first GTPase which was described to be secreted by eukaryotic cells. Here, we report that precipitation of GBP-1 with GMP-agarose from cell culture supernatants co-purified a 47-kD fragment of GBP-1 (p47-GBP-1) in addition to the 67-kD full-length form. MALDI-TOF sequencing revealed that p47-GBP-1 corresponds to the C-terminal helical part of GBP-1 and lacks most of the globular GTPase domain. In silico analyses of protease target sites, together with cleavage experiments in vitro and in vivo, showed that p67-GBP-1 is cleaved by the inflammatory caspases 1 and 5, leading to the formation of p47-GBP-1. Furthermore, the secretion of p47-GBP-1 was found to occur via a non-classical secretion pathway and to be dependent on caspase-1 activity but independent of inflammasome activation. Finally, we showed that p47-GBP-1 represents the predominant form of secreted GBP-1, both in cell culture supernatants and, in vivo, in the cerebrospinal fluid of patients with bacterial meningitis, indicating that it may represent the biologically active form of extracellular GBP-1. These findings confirm the involvement of caspase-1 in non-classical secretion mechanisms and open novel perspectives for the extracellular function of secreted GBP-1.
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Proteínas de Unión al GTP/metabolismo , Inflamación/metabolismo , Inflamación/patología , Procesamiento Proteico-Postraduccional , Adolescente , Adulto , Anciano , Secuencia de Aminoácidos , Caspasa 1/metabolismo , Femenino , Proteínas de Unión al GTP/líquido cefalorraquídeo , Proteínas de Unión al GTP/química , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Inflamasomas/metabolismo , Interferón gamma/farmacología , Masculino , Meningitis Bacterianas/líquido cefalorraquídeo , Meningitis Bacterianas/metabolismo , Persona de Mediana Edad , Peso Molecular , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Adulto JovenRESUMEN
"Candidatus Neoehrlichia mikurensis" is the tick-borne agent of neoehrlichiosis, an infectious disease that primarily affects immunocompromised patients. So far, the genetic variability of "Ca. Neoehrlichia" has been studied only by comparing 16S rRNA genes and groEL operon sequences. We describe the development and use of a multilocus sequence analysis (MLSA) protocol to characterize the genetic diversity of clinical "Ca. Neoehrlichia" strains in Europe and their relatedness to other species within the Anaplasmataceae family. Six genes were selected: ftsZ, clpB, gatB, lipA, groEL, and 16S rRNA. Each MLSA locus was amplified by real-time PCR, and the PCR products were sequenced. Phylogenetic trees of MLSA locus relatedness were constructed from aligned sequences. Blood samples from 12 patients with confirmed "Ca. Neoehrlichia" infection from Sweden (n = 9), the Czech Republic (n = 2), and Germany (n = 1) were analyzed with the MLSA protocol. Three of the Swedish strains exhibited identical lipA sequences, while the lipA sequences of the strains from the other nine patients were identical to each other. One of the Czech strains had one differing nucleotide in the clpB sequence from the sequences of the other 11 strains. All 12 strains had identical sequences for the genes 16S rRNA, ftsZ, gatB, and groEL. According to the MLSA, among the Anaplasmataceae, "Ca. Neoehrlichia" is most closely related to Ehrlichia ruminantium, less so to Anaplasma phagocytophilum, and least to Wolbachia endosymbionts. To conclude, three sequence types of infectious "Ca. Neoehrlichia" were identified: one in the west of Sweden, one in the Czech Republic, and one spread throughout Europe.
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Infecciones por Anaplasmataceae/microbiología , Anaplasmataceae/clasificación , Anaplasmataceae/genética , Variación Genética , Genotipo , Tipificación de Secuencias Multilocus/métodos , Anciano , Anaplasmataceae/aislamiento & purificación , Infecciones por Anaplasmataceae/epidemiología , Análisis por Conglomerados , República Checa/epidemiología , Femenino , Genes Esenciales , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular/métodos , Filogenia , ARN Ribosómico 16S/genética , Suecia/epidemiologíaRESUMEN
Infective endocarditis (IE) is still a life-threatening disease with high morbidity and mortality. While usually caused by a single bacterium, poly-microbial infective endocarditis (IE) is rare. Here, we report a (blood-culture-negative) dual pathogen mitral valve IE caused by Coxiella burnetii and Streptococcus gordonii: A 53-year-old woman was presented to an internal medicine department with abdominal pain for further evaluation. Within the diagnostic work up, transthoracic echocardiography (TTE) revealed an irregularly shaped echogenic mass (5 × 13 mm) adherent to the edge of the posterior mitral valve leaflet and protruding into the left atrium. As infected endocarditis was suspected, blood cultures were initially obtained, but they remained negative. Chronic Q fever infection was diagnosed using serologic testing. After the occurrence of cerebral thromboembolic events, the patient was admitted for mitral valve surgery. Intraoperatively, a massively destructed mitral valve with adhering vegetations was noted. Examination of the mitral valve by broad-range bacterial polymerase chain reaction (PCR) and amplicon sequencing confirmed Coxiella burnetii infection and yielded Streptococcus gordonii as the second pathogen. Based on the detailed diagnosis, appropriate antibiotic therapy of both pathogens was initiated, and the patient could be discharged uneventfully on the 11th postoperative day after a successful minimal-invasive mitral valve replacement.
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"Classical" Whipple's disease (cWD) is caused by Tropheryma whipplei and is characterized by arthropathy, weight loss, and diarrhea. T. whipplei infectious endocarditis (TWIE) is rarely reported, either in the context of cWD or as isolated TWIE without signs of systemic infection. The frequency of TWIE is unknown, and systematic studies are lacking. Here, we performed an observational cohort study on the incidence of T. whipplei infection in explanted heart valves in two German university centers. Cardiac valves from 1,135 patients were analyzed for bacterial infection using conventional culture techniques, PCR amplification of the bacterial 16S rRNA gene, and subsequent sequencing. T. whipplei-positive heart valves were confirmed by specific PCR, fluorescence in situ hybridization, immunohistochemistry, histological examination, and culture for T. whipplei. Bacterial endocarditis was diagnosed in 255 patients, with streptococci, staphylococci, and enterococci being the main pathogens. T. whipplei was the fourth most frequent pathogen, found in 16 (6.3%) cases, and clearly outnumbered Bartonella quintana, Coxiella burnetii, and members of the HACEK group (Haemophilus species, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae). In this cohort, T. whipplei was the most commonly found pathogen associated with culture-negative infective endocarditis.
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Infecciones por Actinomycetales/epidemiología , Infecciones por Actinomycetales/microbiología , Endocarditis Bacteriana/epidemiología , Endocarditis Bacteriana/microbiología , Tropheryma/aislamiento & purificación , Centros Médicos Académicos , Infecciones por Actinomycetales/patología , Anciano , Técnicas Bacteriológicas , Estudios de Cohortes , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Endocarditis Bacteriana/patología , Femenino , Alemania/epidemiología , Válvulas Cardíacas/microbiología , Válvulas Cardíacas/patología , Histocitoquímica , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Incidencia , Masculino , Microscopía , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
Recently, a new genus of Anaplasmataceae termed "Candidatus Neoehrlichia" was discovered in ticks and rodents. Here, we report on two patients who suffered from febrile bacteremia due to "Candidatus Neoehrlichia mikurensis" associated with thrombotic or hemorrhagic events. 16S rRNA and groEL gene sequencing provided evidence of three groups of sequence variants.
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Infecciones por Anaplasmataceae/microbiología , Anaplasmataceae/aislamiento & purificación , Fiebre/microbiología , Anciano , Anaplasmataceae/genética , Infecciones por Anaplasmataceae/diagnóstico , Infecciones por Anaplasmataceae/tratamiento farmacológico , Antibacterianos/uso terapéutico , Bacteriemia/diagnóstico , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Médula Ósea/microbiología , ADN Bacteriano/química , Europa (Continente) , Resultado Fatal , Genes Bacterianos/genética , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Enfermedades por Picaduras de Garrapatas/diagnóstico , Enfermedades por Picaduras de Garrapatas/tratamiento farmacológico , Enfermedades por Picaduras de Garrapatas/microbiologíaRESUMEN
No proper treatment option for peri-implantitis exists yet. Based on previous studies showing the in vitro effectiveness of electrochemical disinfection using boron-doped diamond electrodes, novel double diamond electrodes (DDE) were tested here. Using a ceramic carrier and a laser structuring process, a clinically applicable electrode array was manufactured. Roughened metal discs (n = 24) made from Ti-Zr alloy were exposed to the oral cavities of six volunteers for 24 h in order to generate biofilm. Then, biofilm removal was carried out either using plastic curettes and chlorhexidine digluconate or electrochemical disinfection. In addition, dental implants were contaminated with ex vivo multispecies biofilm and disinfected using DDE treatment. Bacterial growth and the formation of biofilm polymer were determined as outcome measures. Chemo-mechanical treatment could not eliminate bacteria from roughened surfaces, while in most cases, a massive reduction of bacteria and biofilm polymer was observed following DDE treatment. Electrochemical disinfection was charge- and time-dependent and could also not reach complete disinfection in all instances. Implant threads had no negative effect on DDE treatment. Bacteria exhibit varying resistance to electrochemical disinfection with Bacillus subtilis, Neisseria sp., Rothiamucilaginosa, Staphylococcus haemolyticus, and Streptococcus mitis surviving 5 min of DDE application at 6 V. Electrochemical disinfection is promising but requires further optimization with respect to charge quantity and application time in order to achieve disinfection without harming host tissue.
RESUMEN
Colistin (polymyxin E) is a membrane-destabilizing antibiotic used against Gram-negative bacteria. We have recently reported that the outer membrane prevents the uptake of antibacterial chlorophyllin into Gram-negative cells. In this study, we used sub-toxic concentrations of colistin to weaken this barrier for a combination treatment of Escherichia coli and Salmonella enterica serovar Typhimurium with chlorophyllin. In the presence of 0.25 µg/mL colistin, chlorophyllin was able to inactivate both bacteria strains at concentrations of 5-10 mg/L for E. coli and 0.5-1 mg/L for S. Typhimurium, which showed a higher overall susceptibility to chlorophyllin treatment. In accordance with a previous study, chlorophyllin has proven antibacterial activity both as a photosensitizer, illuminated with 12 mW/cm2, and in darkness. Our data clearly confirmed the relevance of the outer membrane in protection against xenobiotics. Combination treatment with colistin broadens chlorophyllin's application spectrum against Gram-negatives and gives rise to the assumption that chlorophyllin together with cell membrane-destabilizing substances may become a promising approach in bacteria control. Furthermore, we demonstrated that colistin acts as a door opener even for the photodynamic inactivation of colistin-resistant (mcr-1-positive) E. coli cells by chlorophyllin, which could help us to overcome this antimicrobial resistance.
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A 38-year-old patient developed meningitis after a complicated kidney transplantation and organ rejection. Ureaplasma urealyticum was identified as the etiological agent by molecular and microbiological analyses of the cerebrospinal fluid. The patient was successfully treated with doxycycline and chloramphenicol. This is the first report of Ureaplasma urealyticum meningitis in an adult.
Asunto(s)
Trasplante de Riñón/efectos adversos , Meningitis Bacterianas/microbiología , Infecciones por Ureaplasma/microbiología , Ureaplasma urealyticum/aislamiento & purificación , Adulto , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Líquido Cefalorraquídeo/microbiología , Cloranfenicol/uso terapéutico , Girasa de ADN/genética , Topoisomerasa de ADN IV/genética , Doxiciclina/uso terapéutico , Farmacorresistencia Bacteriana/genética , Humanos , Masculino , Meningitis Bacterianas/tratamiento farmacológico , Datos de Secuencia Molecular , Quinolonas/farmacología , Análisis de Secuencia de ADN , Resultado del Tratamiento , Infecciones por Ureaplasma/tratamiento farmacológico , Ureaplasma urealyticum/clasificación , Ureaplasma urealyticum/efectos de los fármacos , Ureaplasma urealyticum/genéticaRESUMEN
PURPOSE: First report of a patient with Borrelia-associated crystalline keratopathy with intracorneal evidence of Borrelia garinii by polymerase chain reaction (PCR) and electron microscopy (EM). METHODS: Report of a 67-year-old patient with medical history of recurrent iridocyclitis and arthritis presented with a bilateral, progressive, asymmetric crystalline keratopathy, which was particularly pronounced in the peripheral temporal superior cornea. After penetrating keratoplasty, crystalline keratopathy with stromal haziness recurred. Corneal regrafting was performed. The corneal specimen from the penetrating keratoplasty was examined by light and EM as well as by PCR. RESULTS: In the explanted corneal graft, as well as retrospectively in the corneal specimen from the first keratoplasty, spirochetelike bodies and fragments were detected by light and EM. Borrelia burgdorferi sensu lato DNA was demonstrated by broad-range (16S rDNA) PCR. A more precise identification as Borrelia garinii serotype 5 was possible by analyses of the flaB and ospA gene sequences. Borrelia-specific serological tests showed borderline titers in immunofluorescence and weak reaction in immunoblot, respectively. CONCLUSIONS: This case illustrates that borreliae must be considered as a cause of crystalline keratopathy; Borrelia-specific serological tests can be false negative; explanted cornea specimens of etiologically unclear crystalline keratopathy should be analyzed by EM or PCR for detection of pathogens; and prolonged antibiotic treatment might be effective to prevent progression or recurrence of the disease.
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Grupo Borrelia Burgdorferi/genética , Grupo Borrelia Burgdorferi/ultraestructura , Enfermedades de la Córnea/microbiología , Infecciones Bacterianas del Ojo/microbiología , Enfermedad de Lyme/microbiología , Anciano , Artritis/diagnóstico , Artritis/microbiología , Técnicas de Tipificación Bacteriana , Grupo Borrelia Burgdorferi/aislamiento & purificación , Enfermedades de la Córnea/diagnóstico , Enfermedades de la Córnea/cirugía , ADN Bacteriano/análisis , Infecciones Bacterianas del Ojo/diagnóstico , Infecciones Bacterianas del Ojo/cirugía , Humanos , Iridociclitis/diagnóstico , Iridociclitis/microbiología , Queratoplastia Penetrante , Enfermedad de Lyme/diagnóstico , Enfermedad de Lyme/cirugía , Masculino , Microscopía Electrónica , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Recurrencia , ReoperaciónRESUMEN
A 29-year-old woman presented with unilateral, chronic follicular conjunctivitis since 6 weeks. While the conjunctival swab taken from the patient's eye was negative in a Chlamydia (C.) trachomatis-specific PCR, C. felis was identified as etiological agent using a pan-Chlamydia TaqMan-PCR followed by sequence analysis. A pet kitten of the patient was found to be the source of infection, as its conjunctival and pharyngeal swabs were also positive for C. felis. The patient was successfully treated with systemic doxycycline. This report, which presents one of the few documented cases of human C. felis infection, illustrates that standard PCR tests are designed to detect the most frequently seen species of a bacterial genus but might fail to be reactive with less common species. We developed a modified pan-Chlamydia/C. felis duplex TaqMan-PCR assay that detects C. felis without the need of subsequent sequencing. The role of chlamydiae-specific serum antibody titers for the diagnosis of follicular conjunctivitis is discussed.
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OBJECTIVE: The genus Roseomonas comprises a group of pink-pigmented, slow-growing, aerobic, non-fermentative Gram-negative bacteria, which have been isolated from environmental sources such as water and soil, but are also associated with human infections. In the study presented here, Roseomonas mucosa was identified for the first time as part of the endodontic microbiota of an infected root canal and characterised in respect to growth, antibiotic susceptibility and biofilm formation. RESULTS: The isolated R. mucosa strain showed strong slime formation and was resistant to most ß-lactam antibiotics, while it was susceptible to aminoglycosides, carbapenemes, fluorochinolones, polymyxines, sulfonamides and tetracyclines. Biofilm formation on artificial surfaces (glass, polystyrene, gutta-percha) and on teeth was tested using colorimetric and fluorescence microscopic assays. While solid biofilms were formed on glass surfaces, on the hydrophobic surface of gutta-percha points, no confluent but localised, spotty biofilms were observed. Furthermore, R. mucosa was able form biofilms on dentin. The data obtained indicate that R. mucosa can support establishment of endodontic biofilms and furthermore, infected root canals might serve as an entrance pathway for blood stream infections by this emerging pathogen.
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Acetobacteraceae/aislamiento & purificación , Cavidad Pulpar/microbiología , Enfermedades de la Pulpa Dental/microbiología , Infecciones por Bacterias Gramnegativas/microbiología , Acetobacteraceae/efectos de los fármacos , Acetobacteraceae/patogenicidad , Acetobacteraceae/fisiología , Antibacterianos/farmacología , Biopelículas/crecimiento & desarrollo , Humanos , Pruebas de Sensibilidad Microbiana , MicrobiotaRESUMEN
Although generally rising in incidence, intestinal tuberculosis is still rare in western countries and due to unspecific manifestations mainly as ulcerations on endoscopy, diagnosis of intestinal tuberculosis is challenging. Within this report, we describe a case of severe intestinal tuberculosis radiologically and endoscopically masquerading as colorectal cancer with peritoneal carcinomatosis. Our case exemplifies that intestinal tuberculosis needs to be considered as a differential diagnosis in patients at risk and that undelayed and sensitive diagnosis of intestinal tuberculosis is of central importance for avoiding unfavorable disease outcome.
RESUMEN
BACKGROUND: The emergence of multidrug-resistant bacterial microorganisms is a particular challenge for the health care systems. Little is known about the occurrence of methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Gram-negative bacteria (MDRGNB) in patients of palliative care units (PCU). AIM: The primary aim of this study was to determine the carriage of MRSA among patients of a PCU at a German University Hospital and to assess whether the positive cases would have been detected by a risk-factor-based screening-approach. DESIGN: Between February 2014 and January 2015 patients from our PCU were tested for MRSA carriage within 48 hours following admission irrespective of pre-existing risk factors. In addition, risk factors for MRSA colonization were assessed. Samples from the nostrils and, if applicable, from pre-existing wounds were analysed by standardized culture-based laboratory techniques for the presence of MRSA and of other bacteria and fungi. Results from swabs taken prior to admission were also recorded if available. RESULTS: 297 out of 317 patients (93.7%) fulfilled one or more MRSA screening criteria. Swabs from 299 patients were tested. The detection rate was 2.1% for MRSA. All MRSA cases would have been detected by a risk-factor-based screening-approach. Considering the detected cases and the results from swabs taken prior to admission, 4.1% of the patients (n = 13) were diagnosed with MRSA and 4.1% with MDRGNB (n = 13), including two patients with MRSA and MDRGNB (0.6%). The rate of MRSA carriage in PCU patients (4.1%) was elevated compared to the rate seen in the general cohort of patients admitted to our University Hospital (2.7%). CONCLUSIONS: PCU patients have an increased risk to carry MRSA compared to other hospitalized patients. Although a risk factor-based screening is likely to detect all MRSA carriers amongst PCU patients, we rather recommend a universal screening to avoid the extra effort to identify the few risk factor-negative patients (<7%). As we did not perform a systematic MDRGNB screening, further studies are needed to determine the true prevalence of MDRGNB amongst PCU patients.
Asunto(s)
Unidades Hospitalarias , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Cavidad Nasal/microbiología , Cuidados Paliativos , Adulto , Anciano , Anciano de 80 o más Años , Portador Sano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de RiesgoRESUMEN
The authors describe the case of a 40-year-old man suffering from an epidural abscess in the thoracic spine due to a rarely isolated pathogen, Streptobacillus moniliformis, the causative agent of rat bite fever. Besides diffuse abdominal pain, ataxia, paresthesia, hypesthesia, and enhanced reflexes of the lower extremities, the patient suffered from a decreased sensation of bladder filling. His history was also positive for a rat bite 6 weeks earlier. Magnetic resonance imaging showed an epidural, space-occupying lesion compressing the spinal cord at the vertebral levels of T6-8. Neurosurgery revealed an epidural abscess, which was drained via laminectomy (T-7) and excision of the ligamentum flavum (T6-8). The etiological agent S. moniliformis was identified by 16S rRNA-based polymerase chain reaction and sequencing as well as by culture and mass spectrometry. Treatment with penicillin G led to complete resolution of the abscess and clinical recovery of the patient, who regained his bladder-filling sensation and free walking ability. This case demonstrates that careful attention to the patient's history is essential in suspecting unusual bacterial pathogens as the cause of an epidural abscess and initiating the optimal diagnostic procedure and antimicrobial therapy.