RESUMEN
INTRODUCTION: Clostridioides difficile infection (CDI), as a nosocomial disease, is associated with high morbidity and mortality. Even though the incidence of CDI has been declining in Germany in recent years, the individual infection may pose a medical challenge despite therapeutic advances. The aim here is to clarify which gaps practitioners consider to be particularly serious in care and in the existing evidence base. METHODS: In a moderated workshop of German CDI experts the topics considered as relevant were identified. A survey already conducted in five other countries (Australia, France, Great Britain, Canada, and Italy) was adapted and processed by 27 practitioners. During the evaluation, the topics perceived as particularly important were identified, the statements of the specialist groups were compared and changes in opinion were considered. RESULTS: 27 fully completed questionnaires were evaluated. The need for improvement was primarily seen in the prevention of CDI recurrences (74.1%) and the treatment of recurrences (55.6%). Evidence deficits were noted in the treatment of recurrences (55.6%) and identification of risk factors for recurrences (48.1%). Improving care via fecal microbiota transfer (FMT) was named by 70.4%. For guidelines, more clarity (48.1%) and more regular updates (40.7%) were desired. For patients, better education on appropriate antibiotic use (52.0%) and choice of FMT were desired (48.1%). SUMMARY: The German expert view and the international assessment is similar, when asked about the need for improvement in care and evidence gaps in the treatment of patients with CDI: The focus is on prevention and therapy of recurrent CDI. The problem of access to FMT is a German peculiarity that seems to need improvement.
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Infecciones por Clostridium , Humanos , Infecciones por Clostridium/terapia , Infecciones por Clostridium/epidemiología , Alemania , Mejoramiento de la Calidad , Internacionalidad , Testimonio de Experto , Trasplante de Microbiota Fecal , Medicina Basada en la Evidencia , Evaluación de Necesidades , Infección Hospitalaria/prevención & control , Infección Hospitalaria/epidemiología , Infección Hospitalaria/terapia , Guías de Práctica Clínica como AsuntoRESUMEN
PURPOSES: Despite reports of a declining incidence over the last decade, Clostridioides difficile infection (CDI) is still considered the most important healthcare-associated causes of diarrhea worldwide. In Germany, several measures have been taken to observe, report, and influence this development. This report aims to analyze the development of hospital coding for CDI in Germany over the last decade and to use it to estimate the public health burden caused by CDI. METHODS: Reports from the Institute for Hospital Remuneration Systems, German Federal Statistical Office (DESTATIS), the Robert-Koch-Institute (RKI), Saxonian authorities and hospital quality reports during 2010-2021 were examined for CDI coding and assessed in a structured expert consultation. Analysis was performed using 2019 versions of Microsoft Excel® and Microsoft Access®. RESULTS: Peaks of 32,203 cases with a primary diagnosis (PD) of CDI and 78,648 cases with a secondary diagnosis (SD) of CDI were observed in 2015. The number of cases had decreased to 15,412 PD cases (- 52.1%) and 40,188 SD cases (- 48.9%) by 2021. These results were paralleled by a similar decline in notifiable severe cases. However, average duration of hospitalization of the cases remained constant during this period. CONCLUSIONS: Hospital coding of CDI and notification to authorities has approximately halved from 2015 to 2021. Potential influential factors include hospital hygiene campaigns, implementation of antibiotic stewardship programs, social distancing due to the COVID-19 pandemic, and a decrease in more pathogenic subtypes of bacteria. Further research is necessary to validate the multiple possible drivers for this development.
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Clostridioides difficile , Infecciones por Clostridium , Infección Hospitalaria , Humanos , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Pandemias , Infecciones por Clostridium/epidemiología , Infecciones por Clostridium/microbiología , Alemania/epidemiologíaRESUMEN
BACKGROUND: Tropheryma whipplei (TW) can cause different pathologies, e.g., Whipple's disease and transient gastroenteritis. The mechanism by which the bacteria pass the intestinal epithelial barrier, and the mechanism of TW-induced gastroenteritis are currently unknown. METHODS: Using ex vivo disease models comprising human duodenal mucosa exposed to TW in Ussing chambers, various intestinal epithelial cell (IEC) cultures exposed to TW and a macrophage/IEC coculture model served to characterize endocytic uptake mechanisms and barrier function. RESULTS: TW exposed ex vivo to human small intestinal mucosae is capable of autonomously entering IECs, thereby invading the mucosa. Using dominant-negative mutants, TW uptake was shown to be dynamin- and caveolin-dependent but independent of clathrin-mediated endocytosis. Complementary inhibitor experiments suggested a role for the activation of the Ras/Rac1 pathway and actin polymerization. TW-invaded IECs underwent apoptosis, thereby causing an epithelial barrier defect, and were subsequently subject to phagocytosis by macrophages. CONCLUSIONS: TW enters epithelia via an actin-, dynamin-, caveolin-, and Ras-Rac1-dependent endocytosis mechanism and consecutively causes IEC apoptosis primarily in IECs invaded by multiple TW bacteria. This results in a barrier leak. Moreover, we propose that TW-packed IECs can be subject to phagocytic uptake by macrophages, thereby opening a potential entry point of TW into intestinal macrophages.
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Gastroenteritis , Tropheryma , Humanos , Tropheryma/fisiología , Actinas/metabolismo , Macrófagos/microbiología , Mucosa Intestinal/metabolismo , Gastroenteritis/microbiologíaRESUMEN
BACKGROUND: A recently developed haemostatic peptide gel for endoscopic application has been introduced to improve the management of gastrointestinal bleeding. The aim of this pilot study was to evaluate the feasibility, safety, efficacy and indication profiles of PuraStat in a clinical setting. METHODS: In this prospective observational multicentre pilot study, patients with acute non-variceal gastrointestinal bleeding (upper and lower) were included. Primary and secondary application of PuraStat was evaluated. Haemoglobin, prothrombin time, platelets and transfusion behaviour were documented before and after haemostasis. The efficacy of PuraStat was assessed during the procedure, at 3 days and 1 week after application. RESULTS: 111 patients with acute gastrointestinal bleeding were recruited into the study. 70 percent (78/111) of the patients had upper gastrointestinal bleeding and 30% (33/111) had lower gastrointestinal bleeding. After primary application of PuraStat, initial haemostatic success was achieved in 94% of patients (74/79, 95% CI 88-99%), and in 75% of the patients when used as a secondary haemostatic product, following failure of established techniques (24/32, 95% CI 59-91%). The therapeutic success rates (absence of rebleeding) after 3 and 7 days were 91% and 87% after primary use, and 87% and 81% in all study patients. Overall rebleeding rate at 30 day follow-up was 16% (18/111). In the 5 patients who finally required surgery (4.5%), PuraStat allowed temporary haemostasis and stabilisation. CONCLUSIONS: PuraStat expanded the therapeutic toolbox available for an effective treatment of gastrointestinal bleeding sources. It could be safely applied and administered without complications as a primary or secondary therapy. PuraStat may additionally serve as a bridge to surgery in order to achieve temporary haemostasis in case of refractory severe bleeding, possibly playing a role in preventing immediate emergency surgery.
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Hemostasis Endoscópica , Hemostáticos , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/cirugía , Hemostasis Endoscópica/métodos , Hemostáticos/uso terapéutico , Humanos , Proyectos Piloto , Estudios Prospectivos , Resultado del TratamientoRESUMEN
BACKGROUND: Ineffective antibiotic therapy increases mortality of acute cholangitis. The choice of antibiotics should reflect local resistance patterns and avoid the overuse of broad-spectrum agents. In this study, we analysed how results of bile and blood cultures and patient data can be used for selection of empirical antibiotic therapy in acute cholangits. METHODS: Pathogen frequencies and susceptibility rates were determined in 423 positive bile duct cultures and 197 corresponding blood cultures obtained from 348 consecutive patients with acute cholangitis. Patient data were retrieved from the medical records. Associations of patient and microbiological data were assessed using the Chi-2 test and multivariate binary logistic regression. RESULTS: In bile cultures, enterobacterales and enterococci were isolated with equal frequencies of approximately 30% whereas in blood cultures, enterobacterales predominated (56% compared to 21% enterococci). Antibiotic resistance rates of enterobacterales were > 20% for fluorochinolones, cephalosporines and acylureidopenicillins but not for carbapenems (< 2%). The efficacy of empirical therapy was poor with a coverage of bacterial bile and blood culture isolates in 51 and 69%, respectively. By multivariate analysis, predictors for pathogen species, antibiotic susceptibility and expected antibiotic coverage were identified. CONCLUSIONS: In unselected patients treated for acute cholangitis in a large tertiary refferential center, use of carbapenems seems necessary to achieve a high antibiotic coverage. However, by analysis of patient and microbiological data, subgroups for highly effective carbapenem-sparing therapy can be defined. For patients with community-acquired cholangitis without biliary prosthesis who do not need intensive care, piperacillin/tazobactam represents a regimen with an expected excellent antibiotic coverage.
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Antibacterianos/uso terapéutico , Colangitis/tratamiento farmacológico , Colangitis/microbiología , Toma de Decisiones Clínicas , Pruebas de Sensibilidad Microbiana , Enfermedad Aguda , Bilis/microbiología , Cultivo de Sangre , Farmacorresistencia Bacteriana , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/aislamiento & purificación , Enterococcus/efectos de los fármacos , Enterococcus/aislamiento & purificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de RiesgoRESUMEN
CD8+ T cells in the intestinal mucosa influence the HIV-associated pathogenesis, but little is known about the dynamics of mucosal CD8+ T cell counts and activation of these cells during the course of infection. In this study, mucosal CD8+ T cells in the duodenum were studied at different stages of HIV infection, starting from the seronegative phase. In seronegative acute HIV infection, CD8+ T cell counts increased in the epithelium, but not in the lamina propria. Infiltration of the lamina propria by peripherally expanded CD8+ T cells was observed after seroconversion. Highest increase in the expression of perforin, the rate-limiting molecule for cytotoxic CD8+ T cell activity, was evident in the lamina propria of seronegative acutely HIV-infected patients. The number of perforin-expressing cells in the lamina propria of acutely HIV-infected patients was positively associated with biomarkers of enterocyte damage and microbial translocation. After seroconversion, perforin expression was downregulated in the lamina propria, but not in the epithelium. In conclusion, our findings demonstrate that intraepithelial and lamina propria CD8+ T cells exhibit different dynamics of numerical alteration and cytotoxic activity in HIV-infected patients. Moreover, our results suggest that perforin-dependent cytotoxic mechanisms by CD8+ T cells could impair the intestinal mucosal barrier already in the seronegative phase of acute HIV infection, thereby inducing microbial translocation as one of the earliest pathological events in HIV infection.
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Linfocitos T CD8-positivos/inmunología , Infecciones por VIH/inmunología , Seropositividad para VIH/inmunología , Mucosa Intestinal/inmunología , Activación de Linfocitos/inmunología , Adulto , Duodeno/inmunología , Femenino , Citometría de Flujo , Humanos , Inmunohistoquímica , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
During six years as German National Consultant Laboratory for Spirochetes we investigated 149 intestinal biopsies from 91 patients, which were histopathologically diagnosed with human intestinal spirochetosis (HIS), using fluorescence in situ hybridization (FISH) combined with 16S rRNA gene PCR and sequencing. Aim of this study was to complement histopathological findings with FISH and PCR for definite diagnosis and species identification of the causative pathogens. HIS is characterized by colonization of the colonic mucosa of the human distal intestinal tract by Brachyspira spp. Microbiological diagnosis of HIS is not performed, because of the fastidious nature and slow growth of Brachyspira spp. in culture. In clinical practice, diagnosis of HIS relies solely on histopathology without differentiation of the spirochetes. We used a previously described FISH probe to detect and identify Brachyspira spp. in histological gut biopsies. FISH allowed rapid visualization and identification of Brachyspira spp. in 77 patients. In most cases, the bright FISH signal already allowed rapid localization of Brachyspira spp. at 400× magnification. By sequencing, 53 cases could be assigned to the B. aalborgi lineage including "B. ibaraki" and "B. hominis", and 23 cases to B. pilosicoli. One case showed mixed colonization. The cases reported here reaffirm all major HIS Brachyspira spp. clusters already described. However, the phylogenetic diversity seems to be even greater than previously reported. In 14 cases, we could not confirm HIS by either FISH or PCR, but found colonization of the epithelium by rods and cocci, indicating misdiagnosis by histopathology. FISH in combination with molecular identification by 16S rRNA gene sequencing has proved to be a valuable addition to histopathology. It provides definite diagnosis of HIS and allows insights into phylogeny and distribution of Brachyspira spp. HIS should be considered as a differential diagnosis in diarrhea of unknown origin, particularly in patients from risk groups (e.g. patients with colonic adenomas, inflammatory polyps, inflammatory bowel disease or HIV infection and in men who have sex with men).
Asunto(s)
Brachyspira/clasificación , Brachyspira/aislamiento & purificación , Variación Genética , Infecciones por Bacterias Gramnegativas/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brachyspira/genética , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Femenino , Genes de ARNr , Humanos , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana Edad , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Adulto JovenRESUMEN
BACKGROUND AND STUDY AIMS: Hemostatic powders have been introduced to improve the management of gastrointestinal (GI) bleeding and to extend the variety of tools available for emergency endoscopy. The aim of the present pilot study was to evaluate the indication profiles and the short-term outcome of EndoClot. PATIENTS, MATERIALS AND METHODS: In a prospective observational pilot study patients with acute nonvariceal GI bleeding were included. Primary or secondary application of EndoClot was assessed. Hemoglobin, prothrombine time and platelets were documented before and after hemostasis. The efficacy of EndoClot was assessed 72 hours and 1 week after application. RESULTS: Seventy patients with acute GI bleeding were recruited into the study. Eighty-three percent (58/70) of the patients had upper and 17% (12/70) had lower GI bleeding. In the upper GI tract treatment success was achieved in 64% (30/47, 95% confidence interval, 50%-76%) after primary use and in all patients, when used after established techniques had failed (95% confidence interval, 70%-100%). In lower GI bleeding hemostasis was achieved in 83% of cases (10/12, 95% confidence interval 54%-97%). Rebleeding occurred in 11% (8/70), in 10% EndoClot served as a bridge to surgery (7/70). CONCLUSIONS: EndoClot expanded the therapeutic options in the management of GI bleeding. It was applicable as a monotherapy or in combination with other techniques from oozing bleeding type or lower. It was most effective in diffuse or extensive bleeding activity or when access to the bleeding vessel was difficult. EndoClot can be applied as a bridge to surgery when classical methods of hemostasis have failed.
Asunto(s)
Hemorragia Gastrointestinal/terapia , Polisacáridos/administración & dosificación , Anciano , Femenino , Alemania , Hemostasis Endoscópica , Humanos , Masculino , Proyectos Piloto , Complicaciones Posoperatorias , Estudios Prospectivos , Resultado del TratamientoRESUMEN
BACKGROUND: Inflammatory bowel disease (IBD)-like conditions in glycogen storage disease (GSD) type Ib have been predominantly described in children. Signs and symptoms of GSD type Ib are hypoglycemia, pancytopenia and hepatosplenomegaly. Based on few published cases, there is evidence that granulocyte-colony stimulating factor (G-CSF) in patients with glycogenosis-related pancytopenia might ameliorate the IBD-like disease through leukocyte increase. CASE PRESENTATION: Here we firstly describe a case of an adult 33-year-old Caucasian male patient with GSD type Ib accompanied with IBD-like disease with persistent pancytopenia despite moderate-dose G-CSF treatment. Recent vomiting and abdominal discomfort were due to a high-grade stenosis in the transverse colon. A dose increase of the G-CSF successfully normalized his leukocyte count. However, the stenosis worsened and surgical therapy was needed. CONCLUSION: We suggest that symptomatic patients with GSD type Ib should undergo endoscopic examination in order to detect IBD-like disease and to initiate early treatment.
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Colon Transverso/patología , Enfermedades del Colon/etiología , Enfermedad del Almacenamiento de Glucógeno Tipo I/complicaciones , Enfermedades Inflamatorias del Intestino/complicaciones , Pancitopenia/tratamiento farmacológico , Adulto , Colon Transverso/cirugía , Enfermedades del Colon/cirugía , Colonoscopía , Constricción Patológica/etiología , Constricción Patológica/cirugía , Factor Estimulante de Colonias de Granulocitos y Macrófagos/administración & dosificación , Humanos , Recuento de Leucocitos , Masculino , Pancitopenia/etiologíaRESUMEN
BACKGROUND: Mucosal macrophages are involved in the maintenance of epithelial barrier integrity and the elimination of invading pathogens. Although an intestinal barrier defect and microbial translocation are hallmarks of human immunodeficiency virus (HIV) infection, recent data on gut mucosal macrophages in HIV infection are sparse. METHODS: Treatment-naive and treated HIV-infected patients and healthy controls were studied for frequencies and functional parameters of blood monocytes and macrophages in duodenal mucosa. RESULTS: We found mucosal enrichment of macrophages in untreated HIV infection associated with reduced monocyte counts in blood and increased monocyte expression of the gut-homing molecule integrin ß7. Increased CCR2 density on integrin ß7-expressing monocytes and mucosal secretion of CCL2 suggest that CCR2/CCL2-chemotaxis is involved in enhanced trafficking of blood monocytes to the gut. Secretion of macrophage-related proinflammatory molecules interleukin 1ß, CCL5, CXCL9, and CXCL10 was increased in the gut mucosa of untreated patients. Moreover, mucosal macrophages of untreated patients showed reduced phagocytic activity. CONCLUSIONS: These data suggest a role for gut mucosal macrophages in HIV immune pathogenesis: infiltrated macrophages in the intestinal mucosa may promote local inflammation and tissue injury, whereas their low phagocytic activity prevents the efficient elimination of luminal antigens that cross the damaged intestinal barrier.
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Tracto Gastrointestinal/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , Mucosa Intestinal/inmunología , Macrófagos/inmunología , Adulto , Anciano , Quimiocina CCL2/inmunología , Quimiocina CCL5/inmunología , Quimiocina CXCL10/inmunología , Quimiocina CXCL9/inmunología , Duodeno/inmunología , Duodeno/virología , Femenino , Tracto Gastrointestinal/virología , Infecciones por VIH/virología , Humanos , Cadenas beta de Integrinas/inmunología , Interleucina-1beta/inmunología , Mucosa Intestinal/virología , Macrófagos/virología , Masculino , Persona de Mediana Edad , Monocitos/inmunología , Monocitos/virología , Fagocitosis/inmunología , Receptores CCR2/inmunología , Adulto JovenRESUMEN
Based on indirect evidence, increased mucosal translocation of gut-derived microbial macromolecules has been proposed as an important pathomechanism in HIV infection. Here, we quantified macromolecule translocation across intestinal mucosa from treatment-naive HIV-infected patients, HIV-infected patients treated by combination antiretroviral therapy, and HIV-negative controls and analyzed the translocation pathways involved. Macromolecule permeability was quantified by FITC-Dextran 4000 (FD4) and horseradish peroxidase (HRP) flux measurements. Translocation pathways were addressed using cold inhibition experiments. Tight junction proteins were characterized by immunoblotting. Epithelial apoptosis was quantified and translocation pathways were further characterized by flux studies in T84 cell monolayers using inducers and inhibitors of apoptosis and endocytosis. In duodenal mucosa of untreated but not treated HIV-infected patients, FD4 and HRP permeabilities were more than a 4-fold increase compared to the HIV-negative controls. Duodenal macromolecule permeability was partially temperature-dependent and associated with epithelial apoptosis without altered expression of the analyzed tight junction proteins. In T84 monolayers, apoptosis induction increased, and both apoptosis and endocytosis inhibitors reduced macromolecule permeability. Using quantitative analysis, we demonstrate the increased macromolecule permeability of the intestinal mucosa in untreated HIV-infected patients. Combining structural and mechanistic studies, we identified two pathways of increased macromolecule translocation in HIV infection: transcytosis and passage through apoptotic leaks.
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Infecciones por VIH , Humanos , Infecciones por VIH/metabolismo , Mucosa Intestinal/metabolismo , Proteínas de Uniones Estrechas/metabolismo , Duodeno/metabolismo , TranscitosisRESUMEN
BACKGROUND: Aeromonads cause a variety of infections, including gastroenteritis, sepsis, and wound necrosis. Pathogenesis of Aeromonas hydrophila and its hemolysin has been characterized, but the mechanism of the epithelial barrier dysfunction is currently poorly understood. METHODS: Human colon epithelial monolayers HT-29/B6 were apically inoculated with clinical isolates of A. hydrophila or with the secreted pore-forming toxin aerolysin. Epithelial resistance and permeability for several markers were determined in Ussing chambers, using 2-path impedance spectroscopy. The subcellular distribution of tight junction (TJ) and cytoskeleton proteins was analyzed by Western blotting and confocal laser-scanning microscopy. RESULTS: A. hydrophila infection induces chloride secretion with a small decrease in transcellular resistance. However, the major effect of A. hydrophila, mediated by its toxin aerolysin, was a sustained reduction of paracellular resistance by retracting sealing TJ proteins from the TJ strands. Aerolysin-treated monolayers showed increased paracellular permeability to FITC-dextran-4000 (0.104 ± 0.014 vs 0.047 ± 0.001 10(-6) cm/s in control; P < .05). Moreover, restitution of epithelial lesions was impaired. The effects were myosin light chain kinase (MLCK) dependent and mediated by intracellular Ca(2+) signaling. CONCLUSIONS: During Aeromonas infection, pore formation by aerolysin impairs epithelial integrity by promoting TJ protein redistribution and consequently affecting wound closure. Thus, Aeromonas-induced diarrhea is mediated by 2 mechanisms, transcellular secretion and paracellular leak flux.
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Aeromonas hydrophila/fisiología , Permeabilidad de la Membrana Celular/fisiología , Diarrea/microbiología , Infecciones por Bacterias Gramnegativas/fisiopatología , Mucosa Intestinal/microbiología , Proteínas Citotóxicas Formadoras de Poros/fisiología , Uniones Estrechas/fisiología , Aeromonas hydrophila/metabolismo , Toxinas Bacterianas , Western Blotting , Calcio/fisiología , Diarrea/fisiopatología , Espectroscopía Dieléctrica , Infecciones por Bacterias Gramnegativas/microbiología , Células HT29 , Humanos , Mucosa Intestinal/fisiopatología , Microscopía Fluorescente , Quinasa de Cadena Ligera de Miosina/fisiologíaRESUMEN
BACKGROUND & AIMS: A barrier defect of the intestinal mucosa is thought to affect the progression of human immunodeficiency virus (HIV) infection. It is not clear whether the mucosal barrier impairment already is present in acute infection and what mechanisms cause this defect. We analyzed T-cell subsets, epithelial apoptosis, and barrier function of the duodenal mucosa in patients with acute HIV infection. METHODS: Mucosal T-cell subsets, epithelial apoptosis, and barrier function were assessed by immunohistochemistry, immunofluorescence, flow cytometry, and impedance spectroscopy in duodenal samples from 8 patients with early acute infection, 8 patients with chronic infection, and 9 HIV-negative individuals (controls). One patient was analyzed serially, before and during acute infection. RESULTS: Compared with controls, densities of mucosal CD8+ and, surprisingly, of mucosal CD4+ T cells too, increased in patients with acute infection. Most mucosal CD4+ T cells had an activated effector memory phenotype (CD45RA-CD45RO+CD62L-CD40L+CD38+) and did not proliferate. Perforin-expressing mucosal CD8+ T cells also were increased in acutely infected patients; their frequency correlated with epithelial apoptosis. The epithelial barrier was impaired significantly in patients with acute HIV infection. The patient analyzed serially developed increased densities of mucosal CD4+ and CD8+ T cells, increased apoptosis of epithelial cells, and mucosal barrier impairment during acute infection. CONCLUSIONS: Before depleting CD4+ T cells, acute HIV infection induces infiltration of the mucosa with activated effector memory CD4+ and CD8+ T cells. The HIV-induced barrier defect of the intestinal mucosa is evident already in acute infection; it might arise from increased epithelial apoptosis, induced by perforin-positive mucosal cytotoxic T cells.
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Apoptosis , Linfocitos T CD4-Positivos/fisiología , Linfocitos T CD8-positivos/fisiología , Infecciones por VIH/inmunología , Mucosa Intestinal/patología , Enfermedad Aguda , Adulto , Anciano , Duodeno/inmunología , Duodeno/metabolismo , Duodeno/patología , Femenino , Infecciones por VIH/patología , Humanos , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Masculino , Persona de Mediana Edad , Perforina/análisisRESUMEN
The gastrointestinal tract represents a major site for human and simian immunodeficiency virus (HIV and SIV) replication and CD4(+) T-cell depletion. Despite severe depletion of mucosal CD4(+) T cells, FOXP3(+) regulatory CD4(+) T cells (T(reg)) are highly increased in the gut mucosa of chronically HIV-infected individuals and may contribute to HIV pathogenesis, either by their immunosuppressive function or as a significant target cell population for virus production. Little is known about the susceptibility of mucosal T(reg) to viral infection and the longitudinal effect of HIV/SIV infection on T(reg) dynamics. In this study, we determined the level of SIV infection in T(reg) and nonregulatory CD4(+) T cells (non-T(reg)) isolated from the colon of SIV-infected rhesus macaques. The dynamics of mucosal T(reg) and alterations in the mucosal CD4(+) T-cell pool were examined longitudinally. Our findings indicate that mucosal T(reg) were less susceptible to productive SIV infection than non-T(reg) and thus were selectively spared from SIV-mediated cell death. In addition to improved survival, local expansion of T(reg) by SIV-induced proliferation of the mucosal CD4(+) T-cell pool facilitated the accumulation of mucosal T(reg) during the course of infection. High frequency of mucosal T(reg) in chronic SIV infection was strongly related to a reduction of perforin-expressing cells. In conclusion, this study suggests that mucosal T(reg) are less affected by productive SIV infection than non-T(reg) and therefore spared from depletion. Although SIV production is limited in mucosal T(reg), T(reg) accumulation may indirectly contribute to viral persistence by suppressing antiviral immune responses.
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Linfocitos T CD4-Positivos/virología , Factores de Transcripción Forkhead/análisis , Mucosa Intestinal/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Linfocitos T Reguladores/virología , Animales , Apoptosis , Linfocitos T CD4-Positivos/inmunología , Separación Celular , Activación de Linfocitos , Depleción Linfocítica , Macaca mulatta , ARN Viral/biosíntesis , Linfocitos T Reguladores/inmunologíaRESUMEN
Human intestinal spirochetosis (HIS) is associated with overgrowth of the large intestine by spirochetes of the genus Brachyspira. The microbiological diagnosis of HIS is hampered by the fastidious nature and slow growth of Brachyspira spp. In clinical practice, HIS is diagnosed histopathologically, and a significant portion of cases may be missed. Fluorescence in situ hybridization (FISH) is a molecular method that allows the visualization and identification of single bacteria within tissue sections. In this study, we analyzed intestinal biopsy samples from five patients with possible HIS. All specimens yielded positive results by histopathological techniques. PCR amplification and sequencing of the 16S rRNA gene were performed. Sequences of two isolates clustered in the group of Brachyspira aalborgi, whereas in three cases, the sequences were highly similar to that of Brachyspira pilosicoli. Three phylotypes showed mismatches at distinct nucleotide positions with Brachyspira sp. sequences published previously. In addition, culture for Brachyspira was successful in three cases. On the basis of these data, we designed and evaluated a Brachyspira genus-specific 16S rRNA-directed FISH probe that detects all of the Brachyspira spp. published to date. FISH of biopsy samples resulted in strong, unequivocal signals of brush-like formations at the crypt surfaces. This technique allowed simultaneous visualization of single spirochetes and their identification as Brachyspira spp. In conclusion, FISH provides a fast and accurate technique for the visualization and identification of intestinal spirochetes in tissue sections. It therefore represents a valuable tool for routine diagnosis of HIS.
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Brachyspira/genética , Enfermedades Gastrointestinales/microbiología , Infecciones por Bacterias Gramnegativas/diagnóstico , Hibridación Fluorescente in Situ/métodos , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Brachyspira/aislamiento & purificación , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Femenino , Humanos , Mucosa Intestinal/microbiología , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Sondas de Oligonucleótidos/genética , ARN Ribosómico 16S/genética , Sensibilidad y Especificidad , Análisis de Secuencia de ADNRESUMEN
BACKGROUND: Patients with inflammatory bowel disease (IBD) are susceptible to infections. RESULTS: Independently from immunomodulatory therapy, IBD predisposes to infectious complications. Thus, the incidence of Clostridium difficile infection is increased in IBD patients, and a significant proportion of these patients contracts C. difficile infection outside the hospital and without precedent antibiotic use. Cytomegalovirus infection has been reported in cortico- steroid-naive patients with ulcerative colitis, and infectious gastroenteritis has been linked to initiation and exacerbation of IBD. Finally, in Crohn's disease there is a substantial risk for abscess formation, and urinary tract infections occur more frequently than in a non-IBD control population. Apart from the disease process itself, factors that predispose to infectious complications in IBD are malnutrition, advanced age, immunosuppressive medications, leukopenia from immunosuppressive medications, and surgery. However, the main risk for infections is clearly related to the use of immunosuppressive agents such as corticosteroids, azathioprine, methotrexate, cyclosporine, and TNF-blocking biologicals. A wide spectrum of infectious complications has been reported in patients treated with these medications, including viral (e.g. CMV, VZV, EBV), bacterial (e.g. Mycobacteria, Listeria, staphylococci), fungal (e.g. Pneumocystis jiroveci, Aspergillus, Candida, Cryptococcus) and protozoal (Toxoplasma) pathogens. The greatest risks obviously relate to the combined use of immunomodulating agents rather than to individual drugs. The risk of infections is also aggravated by an insufficient immunization status as frequently observed in patients with IBD. CONCLUSION: Physicians treating patients with IBD must be aware of the risk for infectious complications in these patients as well as of strategies to minimize them.
Asunto(s)
Enfermedades Transmisibles/complicaciones , Enfermedades Inflamatorias del Intestino/complicaciones , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Humanos , Inmunosupresores/uso terapéuticoRESUMEN
High-level human immunodeficiency virus (HIV) replication and the rapid breakdown of the mucosal immune system are the hallmarks of HIV infection in the gut. Cytokine dysregulation may be related to both phenomena. Using real-time PCR we quantified the colonic mucosal mRNA expression of selected proinflammatory and regulatory (gamma interferon [IFN-gamma], tumor necrosis factor alpha [TNF-alpha], and interleukin-2 [IL-2], IL-4, IL-6, and IL-10) and HIV-inhibitory (IL-16, CCL3, and CCL5) cytokines for 10 HIV-infected patients before and during 9 months of highly active antiretroviral therapy (HAART). HIV RNA and T-cell dynamics were measured in the colonic mucosa and the blood. Seven HIV-negative individuals served as controls. The mucosal mRNA expression of TNF-alpha, IFN-gamma, IL-4, IL-6, and IL-10 was significantly higher in HIV-infected patients than in control patients and remained elevated during 9 months of HAART despite the decline in blood and mucosal HIV RNA levels and an increase in the level of CD4(+) T lymphocytes. The mRNA levels of CCL3 and CCL5, both of which were elevated before treatment, returned to nearly normal during therapy. Despite reductions in levels of mucosal HIV RNA and the restoration of mucosal CD4(+) T lymphocytes, antiretroviral therapy failed to restore the normal colonic immunologic environment.
Asunto(s)
Terapia Antirretroviral Altamente Activa , Colon/inmunología , Citocinas/metabolismo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Mucosa Intestinal/inmunología , Adulto , Anciano , Recuento de Linfocito CD4 , Citocinas/genética , Cartilla de ADN , Femenino , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Viral/sangre , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Resultado del Tratamiento , Carga ViralRESUMEN
Whereas statistical association of hepatitis C virus (HCV) infection with cardiomyopathy is long known, establishment of a causal relationship has not been achieved so far. Patients with advanced heart failure (HF) are mostly unable to tolerate interferon (IFN)-based treatment, resulting in limited experience regarding the possible pathogenic role of HCV in this patient group. HCV infection often triggers disease in a broad spectrum of extrahepatic organs, with innate immune and autoimmune pathogenic processes involved. The fact that worldwide more than 70 million patients are chronically infected with HCV illustrates the possible clinical impact arising if cardiomyopathies were induced or aggravated by HCV, resulting in progressive HF or severe arrhythmias. A novel path has been opened to finally resolve the long-standing question of cause-effect relationship between HCV infection and cardiac dysfunction, by the recent development of IFN-free, highly efficient, and well tolerable anti-HCV regimens. The new direct-acting antiviral (DAA) agents are highly virus-specific and lack unspecific side-effects upon cardiac function which have always confounded the interpretation of IFN treatment data. The actual frequency of unexplained HF in chronic HCV infection will be determined from a planned large-scale study. Whereas such patients probably constitute a rather small fraction of all those harboring HCV, they have major clinical relevance. It is not yet known which fraction of these patients will significantly benefit from HCV eradication, but this issue will be addressed now in a prospective study.