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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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Infecções por Clostridium , Humanos , Infecções por Clostridium/terapia , Infecções por Clostridium/epidemiologia , Alemanha , Melhoria de Qualidade , Internacionalidade , Prova Pericial , Transplante de Microbiota Fecal , Medicina Baseada em Evidências , Avaliação das Necessidades , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/terapia , Guias de Prática Clínica como AssuntoRESUMO
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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Infecções por HIV , Humanos , Infecções por HIV/metabolismo , Mucosa Intestinal/metabolismo , Proteínas de Junções Íntimas/metabolismo , Duodeno/metabolismo , TranscitoseRESUMO
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 , Infecções por Clostridium , Infecção Hospitalar , Humanos , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Pandemias , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Alemanha/epidemiologiaRESUMO
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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Gastroenterite , Tropheryma , Humanos , Tropheryma/fisiologia , Actinas/metabolismo , Macrófagos/microbiologia , Mucosa Intestinal/metabolismo , Gastroenterite/microbiologiaRESUMO
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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Hemostase Endoscópica , Hemostáticos , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/cirurgia , Hemostase Endoscópica/métodos , Hemostáticos/uso terapêutico , Humanos , Projetos Piloto , Estudos Prospectivos , Resultado do TratamentoRESUMO
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 terapêutico , Colangite/tratamento farmacológico , Colangite/microbiologia , Tomada de Decisão Clínica , Testes de Sensibilidade Microbiana , Doença Aguda , Bile/microbiologia , Hemocultura , Farmacorresistência Bacteriana , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Enterococcus/efeitos dos fármacos , Enterococcus/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
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.
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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).
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Brachyspira/classificação , Brachyspira/isolamento & purificação , Variação Genética , Infecções por Bactérias Gram-Negativas/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brachyspira/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Feminino , Genes de RNAr , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Adulto JovemRESUMO
AIMS: Hepatitis C virus (HCV) has been associated with cardiomyopathies. Former anti-HCV therapies employing interferon could have serious side effects in patients with advanced heart failure since interferon may adversely impact upon cardiac function. We, therefore, examined whether the novel, interferon-free and highly virus-selective anti-HCV combination therapy might be applicable even in advanced or end-stage heart failure. METHODS AND RESULTS: In a retrospective series of HCV-positive patients admitted to our institution with suspected cardiac disease, coronary, valvular or hypertensive heart disease was diagnosed in 70/146 (47.9%). Among the others, 36/76 (47.4%) had myocardial disease: LV (32.9%)/RV (13.2%) hypertrophy, RV dysfunction (13.2%)/dilation (6.6%), severe diastolic dysfunction (7.9%), pulmonary hypertension (22.4%). One critically ill patient listed for heart transplantation (HTX) had previously not tolerated an interferon-based protocol. To still improve her chance of enduring transplant survival, we attempted an interferon-free virus-selective antiviral combination drug protocol under careful monitoring of possible side effects. Regarding clinical status she tolerated this treatment well, with the exception of transient severe hyponatremia requiring substitution. Her NYHA functional class improved from II-IV before to class II immediately after successful complete HCV elimination. CONCLUSIONS: Whereas prevalence of cardiac dysfunction and potential benefit from antiviral treatment was reported previously, there is lack of data regarding the response of patients with advanced heart failure. Since the highly HCV-selective drugs used above do not eliminate other cardiotropic viruses and have no direct effect on inflammation, massive improvement in such critically ill patients indicates a causal role of HCV in their cardiac failure, and of HCV elimination in their functional recovery.
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Implantes Absorvíveis , Antivirais/uso terapêutico , Doença da Artéria Coronariana/cirurgia , Hepatite C Crônica/tratamento farmacológico , Alicerces Teciduais , Idoso , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/etiologia , DNA Viral/análise , Hepacivirus/genética , Hepatite C Crônica/complicações , Hepatite C Crônica/virologia , Humanos , Incidência , Imagem Cinética por Ressonância Magnética , Masculino , Estudos RetrospectivosRESUMO
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.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Soropositividade para HIV/imunologia , Mucosa Intestinal/imunologia , Ativação Linfocitária/imunologia , Adulto , Duodeno/imunologia , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
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.
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Hemorragia Gastrointestinal/terapia , Polissacarídeos/administração & dosagem , Idoso , Feminino , Alemanha , Hemostase Endoscópica , Humanos , Masculino , Projetos Piloto , Complicações Pós-Operatórias , Estudos Prospectivos , Resultado do TratamentoRESUMO
We present the case of a herpes simplex virus-1 [HSV-1] sepsis with severe herpes hepatitis in a young female treated with triple immunosuppressive therapy [adalimumab, azathioprine, prednisolone] for refractory Crohn's disease [CD]. The patient presented with high fever, generalised abdominal tenderness, strongly elevated transaminases, coagulopathy, and pancytopenia. Comprehensive diagnostics including blood HSV-1 polymerase chain reaction [PCR], liver biopsy, and immunohistochemistry revealed the diagnosis of fulminant herpes hepatitis. HSV-1 positivity of cutaneous lesions proved the disseminated nature of the infection. Early treatment with intravenous acyclovir led to a rapid improvement of the patient's condition and resulted in a full recovery of her liver function. This is the first reported case of HSV-sepsis in a patient with CD. Physicians treating inflammatory bowel disease [IBD] patients with combined immunosuppressive therapy should be aware of the possibility of herpes hepatitis, and early empirical antiviral therapy should be considered in immunosuppressed patients presenting with fever and severe anicteric hepatitis.
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Doença de Crohn/tratamento farmacológico , Hepatite Viral Humana/diagnóstico , Herpes Simples/diagnóstico , Herpesvirus Humano 1/isolamento & purificação , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Sepse/diagnóstico , Doença de Crohn/imunologia , Doença de Crohn/virologia , Quimioterapia Combinada , Feminino , Hepatite Viral Humana/imunologia , Herpes Simples/imunologia , Humanos , Imunossupressores/uso terapêutico , Sepse/imunologia , Sepse/virologia , Adulto JovemAssuntos
Antibacterianos/uso terapêutico , Vacina BCG/imunologia , Glucocorticoides/administração & dosagem , Síndrome Inflamatória da Reconstituição Imune/diagnóstico , Síndrome Inflamatória da Reconstituição Imune/tratamento farmacológico , Pulmão/diagnóstico por imagem , Estreptomicina/uso terapêutico , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Tomografia Computadorizada por Raios XRESUMO
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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Colo Transverso/patologia , Doenças do Colo/etiologia , Doença de Depósito de Glicogênio Tipo I/complicações , Doenças Inflamatórias Intestinais/complicações , Pancitopenia/tratamento farmacológico , Adulto , Colo Transverso/cirurgia , Doenças do Colo/cirurgia , Colonoscopia , Constrição Patológica/etiologia , Constrição Patológica/cirurgia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Humanos , Contagem de Leucócitos , Masculino , Pancitopenia/etiologiaRESUMO
BACKGROUND: Knowledge about HIV infection in older persons is becoming increasingly important. CD4⺠T cells are essential for protective immunity, but little is known about the effect of age on the CD4⺠T-cell impairment in HIV infection. METHODS: Treatment-naive patients aged older than 50 or younger than 40 years were studied for absolute and relative frequencies of CD31⺠naive and CD31â» naive CD4⺠T cells, central memory, effector memory, and terminally differentiated CD4⺠T cells, and compared with age-matched controls. In addition, cellular proliferation and cytokine secretion properties were determined. CD4⺠T-cell reconstitution was analyzed in older and younger patients with <350 or ≥ 350 CD4⺠T cells per microliter at initiation of combination antiretroviral therapy (cART). RESULTS: CD4⺠T cells of older but not younger HIV-infected patients showed age-inappropriate low levels of CD31â» naive cells, increased levels of effector memory cells, and enhanced interferonγ and interleukin-17 secretion. Impaired CD4⺠T-cell composition persisted in patients who initiated cART at <350 CD4⺠T cells per microliter. In patients with CD4⺠T cells ≥ 350 per microliter, alterations were less pronounced and were reversible with cART. Compared with age-matched controls, total CD4⺠T-cell counts did not differ between treated younger and older HIV-infected patients. CONCLUSIONS: These data demonstrate that aging enhances the CD4⺠T-cell impairment in HIV-infected persons mainly by a loss of CD31â» naive cells, accumulation of effector memory cells, and increased pro-inflammatory effector functions. Age-related changes in CD4⺠T-cell composition can be prevented by an early initiation of cART.
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Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , Subpopulações de Linfócitos T/imunologia , Adulto , Fatores Etários , Idoso , Antirretrovirais/uso terapêutico , Proliferação de Células , Citocinas/metabolismo , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Adulto JovemRESUMO
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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Trato Gastrointestinal/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Mucosa Intestinal/imunologia , Macrófagos/imunologia , Adulto , Idoso , Quimiocina CCL2/imunologia , Quimiocina CCL5/imunologia , Quimiocina CXCL10/imunologia , Quimiocina CXCL9/imunologia , Duodeno/imunologia , Duodeno/virologia , Feminino , Trato Gastrointestinal/virologia , Infecções por HIV/virologia , Humanos , Cadeias beta de Integrinas/imunologia , Interleucina-1beta/imunologia , Mucosa Intestinal/virologia , Macrófagos/virologia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/virologia , Fagocitose/imunologia , Receptores CCR2/imunologia , Adulto JovemRESUMO
HIV infection induces a barrier defect of the intestinal mucosa, which is closely linked to immune activation and CD4 T cell depletion. The HIV-induced barrier defect is initiated in early acute and maintained through chronic infection. In acute infection, increased epithelial permeability is associated with increased epithelial apoptosis possibly caused by perforin-expressing cytotoxic T cells. In chronic infection, mucosal production of inflammatory cytokines is associated with increased epithelial permeability, epithelial apoptosis, and alterations of epithelial tight junctions. In addition to HIV-induced immune-mediated effects, viral proteins have the potential to directly affect epithelial barrier function. After prolonged viral suppression by antiretroviral therapy, there is, at least partial, restoration of the HIV-associated intestinal mucosal barrier defect despite persisting alterations of the mucosal immune system.
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Infecções por HIV/patologia , Mucosa Intestinal/patologia , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Apoptose/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Humanos , Mucosa Intestinal/efeitos dos fármacos , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/fisiologiaRESUMO
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.