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1.
Mycobacterium tuberculosis (MTb) is the leading cause of death in the setting of AIDS. MTb enhances the pathogenicity and accelerates the course of HIV disease and, furthermore, infection with HIV-1 increases the risk of reactivation or reinfection with MTb. In this study, we show that host-specific recall responses to one pathogen, MTb, has a direct effect upon the regulation of a second pathogen, HIV-1. Using cells from immunocompetent former tuberculosis (TB) patients who displayed either a persistently positive (responsive) or negative (anergic), delayed-type hypersensitivity (DTH) reaction to intradermal injection of purified protein derivative (PPD), we investigated the effect of recall Ags to MTb upon the replication of HIV-1 primary isolates in vitro. We show that HIV-1 replication of a T cell-tropic isolate was significantly impaired in MTb-stimulated PBMC from PPD-anergic donors. Furthermore, these donors displayed a significant increase in CD8(+) T cells and IL-10 levels and lower levels of IL-2 and TNF-alpha relative to PPD-responsive donors in response to PPD stimulation. Strikingly, CD8(+) T cell depletion and blocking of IL-10 significantly increased HIV-1 replication in these PPD-anergic donors, indicating that an immunosuppressive response to MTb recall Ags inhibits HIV-1 replication in PPD-anergic individuals. Therefore, immunotherapeutic approaches aimed at recapitulating Ag-specific MTb anergy in vivo could result in novel and effective approaches to inhibit HIV-1 disease progression in MTb/HIV-1 coinfection.  相似文献   

2.
The factors that contribute to the exceptionally high incidence of Mycobacterium tuberculosis (MTb) disease in HIV(+) persons are poorly understood. Macrophage apoptosis represents a critical innate host cell response to control MTb infection and limit disease. In the current study, virulent live or irradiated MTb (iMTbRv) induced apoptosis of differentiated human U937 macrophages in vitro, in part dependent on TNF-alpha. In contrast, apoptosis of differentiated HIV(+) human U1 macrophages (HIV(+) U937 subclone) was markedly reduced in response to iMTbRv and associated with significantly reduced TNF-alpha release, whereas apoptosis and TNF-alpha release were intact to TLR-independent stimuli. Furthermore, reduced macrophage apoptosis and TNF-alpha release were independent of MTb phagocytosis. Whereas surface expression of macrophage TLR2 and TLR4 was preserved, IL-1 receptor associated kinase-1 phosphorylation and NF-kappaB nuclear translocation were reduced in HIV(+) U1 macrophages in response to iMTbRv. These findings were confirmed using clinically relevant human alveolar macrophages (AM) from healthy persons and asymptomatic HIV(+) persons at clinical risk for MTb infection. Furthermore, in vitro HIV infection of AM from healthy persons reduced both TNF-alpha release and AM apoptosis in response to iMTbRv. These data identify an intrinsic specific defect in a critical macrophage cellular response to MTb that may contribute to disease pathogenesis in HIV(+) persons.  相似文献   

3.
OBJECTIVE: To review the clinical features, treatment and outcome of all known cases of tuberculosis in patients with human immunodeficiency virus (HIV) infection in British Columbia between 1984 and 1990. DESIGN: Retrospective case review. SETTING: Provincial tuberculosis registry and university-affiliated HIV clinic. PATIENTS: All people with HIV infection in whom active tuberculosis was diagnosed during the study period. RESULTS: All 40 patients identified were men; their mean age was 38 years. Of the subjects 30 (75%) were homosexual, 6 (15%) were homosexual and used intravenous drugs, 2 (5%) just used intravenous drugs, and 1 (2%) had had heterosexual contact with prostitutes; for the remaining subject the risk factor for HIV infection was not established. In all cases cultures of specimens from 15 body sources yielded Mycobacterium tuberculosis. Thirty-five of the patients had acquired immunodeficiency syndrome (AIDS), and five had HIV infection uncomplicated except for tuberculosis. In 28 (70%) of the cases no AIDS-defining disease had previously been diagnosed, and in 23 (58%) extrapulmonary tuberculosis represented the AIDS-defining disease. Symptoms at presentation included weight loss (in 80% of the cases), fever (in 75%), cough (in 70%) and night sweats (in 55%). The mean CD4 lymphocyte count was 0.2 x 10(9)/L (in 15 cases). Tuberculin skin test results were positive in 8 of 16 cases. The most striking radiologic finding was intrathoracic adenopathy. All except one of the 36 patients who received appropriate treatment responded favourably at first. Adverse reactions necessitating changes in treatment occurred in 12 (33%) of the cases. Relapse occurred after completion of therapy in two cases (one at 3 weeks and the other at 9 months after treatment was stopped). Tuberculosis was the cause of death in five cases. CONCLUSIONS: Tuberculosis in people with HIV infection commonly presents as extrapulmonary disease and precedes or coincides with other AIDS-defining opportunistic infections. In most cases tuberculosis is the AIDS-defining disease. Even though radiologic findings are often unusual physicians should suspect tuberculosis. A careful examination for evidence of disease at multiple sites should be done. The duration and choice of therapy must be adequate to avoid relapse.  相似文献   

4.
A case of pulmonary infection with Mycobacterium tuberculosis in a patient with the acquired immune deficiency syndrome (AIDS) was studied. Diagnosis of AIDS was confirmed by the finding of pulmonary M tuberculosis with oral and oesophageal candidiasis accompanied by characteristic immunological changes with evidence of infection with human T cell lymphotropic virus III. Treatment of this patient was complicated by an unusual drug interaction between rifampicin and ketoconazole, leading to subtherapeutic serum concentrations and poor clinical response to treatment. Intravenous treatment was more effective than oral treatment. This drug interaction should be studied in greater detail as ketoconazole and rifampicin may be used together to treat patients with candidiasis and infection with M tuberculosis.  相似文献   

5.
Bacterial glutamine synthetases (GSs) are complex dodecameric oligomers that play a critical role in nitrogen metabolism, converting ammonia and glutamate to glutamine. Recently published reports suggest that GS from Mycobacterium tuberculosis (MTb) may be a therapeutic target (Harth, G., and Horwitz, M. A. (2003) Infect. Immun. 71, 456-464). In some bacteria, GS is regulated via adenylylation of some or all of the subunits within the aggregate; catalytic activity is inversely proportional to the extent of adenylylation. The adenylylation and deadenylylation of GS are catalyzed by adenylyl transferase (ATase). Here, we demonstrate via electrospray ionization mass spectrometry that GS from pathogenic M. tuberculosis is adenylylated by the Escherichia coli ATase. The adenylyl group can be hydrolyzed by snake venom phosphodiesterase to afford the unmodified enzyme. The site of adenylylation of MTb GS by the E. coli ATase is Tyr-406, as indicated by the lack of adenylylation of the Y406F mutant, and, as expected, is based on amino acid sequence alignments. Using electrospray ionization mass spectroscopy methodology, we found that GS is not adenylylated when obtained directly from MTb cultures that are not supplemented with glutamine. Under these conditions, the highly related but non-pathogenic Mycobacterium bovis BCG yields partially ( approximately 25%) adenylylated enzyme. Upon the addition of glutamine to the cultures, the MTb GS becomes significantly adenylylated ( approximately 30%), whereas the adenylylation of M. bovis BCG GS does not change. Collectively, the results demonstrate that MTb GS is a substrate for E. coli ATase, but only low adenylylation states are accessible. This parallels the low adenylylation states observed for GS from mycobacteria and suggests the intriguing possibility that adenylylation in the pathogenic versus non-pathogenic mycobacteria is differentially regulated.  相似文献   

6.
BACKGROUND: The gross appearance and cytologic findings in synovial fluid in tuberculous infections are similar to those in other types of chronic synovial effusion. Demonstration of acid-fast bacilli (AFB) is required for a definitive diagnosis of tuberculous effusion; it is reported in only 20% of cases. The presence of frank caseous necrotic material and epithelioid cell granulomas in synovial fluid samples is unusual but strongly indicative of tuberculous infection. CASE: A 28-year-old man, on treatment for pulmonary tuberculosis, presented with a history of right ankle swelling, which was clinically interpreted as nonspecific synovitis. The synovial fluid was yellowish, with fluffy, whitish material. Cytologic smears showed abundant, caseous, necrotic material; a few histiocytic aggregates; and occasional epithelioid cell granulomas. Although stain for AFB was negative, considering the clinical presentation, a diagnosis of tuberculous synovitis could be rendered. CONCLUSION: Caseous, necrotic material and epithelioid granulomas in synovial fluid are highly unusual but, when present, can be considered definitive evidence of tuberculous effusion, particularly in a known case of pulmonary tuberculosis.  相似文献   

7.
8.
Pulmonary cavitation is vital to the persistence and spread of Mycobacterium tuberculosis (MTb), but mechanisms underlying this lung destruction are poorly understood. Fibrillar type I collagen provides the lung's tensile strength, and only matrix metalloproteinases (MMPs) can degrade it at neutral pH. We investigated MTb-infected lung tissue and found that airway epithelial cells adjacent to tuberculosis (Tb) granulomas expressed a high level of MMP-1 (interstitial collagenase). Conditioned media from MTb-infected monocytes (CoMTb) up-regulated epithelial cell MMP-1 promoter activity, gene expression, and secretion, whereas direct MTb infection did not. CoMTb concurrently suppressed tissue inhibitor of metalloprotease-1 (TIMP-1) secretion, further promoting matrix degradation, and in Tb patients very low TIMP-1 expression was detected. MMP-1 up-regulation required synergy between TNF-alpha and G protein-coupled receptor signaling pathways. CoMTb stimulated p38 MAPK phosphorylation, and this is the point of TNF-alpha synergy with G protein-coupled receptor activation. Furthermore, p38 phosphorylation was the switch up-regulating MMP-1 activity and decreasing TIMP-1 secretion. Activated p38 localized to MMP-1-secreting airway epithelial cells in Tb patients. These data reveal a monocyte-epithelial cell network whereby MTb may drive tissue destruction, and they demonstrate that p38 phosphorylation is a key regulatory point in the generation of a matrix-degrading phenotype.  相似文献   

9.
OBJECTIVE--To assess the impact of tuberculosis on mortality in patients with AIDS. DESIGN--Community based cohort study. SETTING--52 centres in 17 countries (AIDS in Europe study). SUBJECTS--5249 patients who were alive and free of tuberculosis one month after the diagnosis of AIDS, enrolled between 1979 and 1989, and followed up until 1992. MAIN OUTCOME MEASURES--Onset of clinically active tuberculosis or death, or both. RESULTS--During a mean follow up period of 15 months 201 (4%) patients developed tuberculosis and 3889 (74%) died. Patients who developed tuberculosis survived significantly longer (median 22 months) than those who did not (median 16 months). This apparent survival advantage was due to patients who survived longer having more opportunity to develop tuberculosis (or any other disease). In models that took into account the time at which tuberculosis was diagnosed, the onset of tuberculosis was associated with a significant increase in mortality (adjusted relative hazard of death 1.34; 95% confidence interval 1.12 to 1.60). CONCLUSIONS--The onset of tuberculosis in patients with AIDS predicts a substantial increase in mortality. Whether this increased mortality is directly attributable to the tuberculosis remains uncertain. If the association is causal preventive chemotherapy and aggressive treatment of tuberculosis could improve survival in AIDS.  相似文献   

10.
Background Histoplasma capsulatum is the causative agent of American histoplasmosis. The relationship between disseminated histoplasmosis and AIDS has been well established. Widespread hematogenous dissemination of Histoplasma capsulatum in HIV positive patients can cause a plethora of clinical manifestations; virtually any organic system can be affected. However, genital ulceration by H. capsulatum in patients with AIDS is a real challenge during investigation of the infection due to the great variety of differential diagnoses that are involved. Method The diagnosis was performed by histopathologic study; H. capsulatum was detected by silver staining (Grocott staining) and confirmed by immunocytochemistry. Results We report three cases of histoplasmosis in patients with AIDS, in which we observed genital ulcers, an unusual form of presentation of this disease. In one of these cases, the treatment resulted in total cure. Conclusion The cases reported herein are to illustrate the plurality of pathologies and clinical manifestations, which may affect immunocompromised patients. The correct diagnosis of fungal diseases in these patients following well established treatment will improve the prognosis.  相似文献   

11.
12.

Background

We studied the incidence of tuberculosis, AIDS, AIDS deaths and AIDS-TB co-infection at the population level in Rio de Janeiro, Brazil where universal and free access to combination antiretroviral therapy has been available since 1997.

Methodology/Principal Findings

This was a retrospective surveillance database match of Rio de Janeiro databases from 1995–2004. Proportions of tuberculosis occurring within 30 days and between 30 days and 1 year after AIDS diagnosis were determined. Generalized additive models fitted with cubic splines with appropriate estimating methods were used to describe rates and proportions over time. Overall, 90,806 tuberculosis cases and 16,891 AIDS cases were reported; 3,125 tuberculosis cases within 1 year of AIDS diagnosis were detected. Tuberculosis notification rates decreased after 1997 from a fitted rate (fR per 100,000) of 166.5 to 138.8 in 2004. AIDS incidence rates increased 26% between 1995 and 1998 (30.7 to 38.7) followed by a 33.3% decrease to 25.8 in 2004. AIDS mortality rates decreased dramatically after antiretroviral therapy was introduced between 1995 (27.5) and 1999 (13.4). The fitted proportion (fP) of patients with tuberculosis diagnosed within one year of AIDS decreased from 1995 (24.4%) to1998 (15.2%), remaining stable since. Seventy-five percent of tuberculosis diagnoses after an AIDS diagnosis occurred within 30 days of AIDS diagnosis.

Conclusions/Significance

Our results suggest that while combination ART should be considered an essential component of the response to the HIV and HIV/tuberculosis epidemics, it may not be sufficient alone to prevent progression from latent TB to active disease among HIV-infected populations. When tuberculosis is diagnosed prior to or at the same time as AIDS and ART has not yet been initiated, then ART is ineffective as a tuberculosis prevention strategy for these patients. Earlier HIV/AIDS diagnosis and ART initiation may reduce TB incidence in HIV/AIDS patients. More specific interventions will be required if HIV-related tuberculosis incidence is to continue to decline.  相似文献   

13.
OBJECTIVE--To examine the contribution of HIV infection to the apparently increasing incidence of tuberculosis in central Africa. DESIGN--Cross sectional study. SETTING--Outpatient clinic in teaching hospital, Lusaka, Zambia. PATIENTS--346 Adult patients with tuberculosis. RESULTS--Overall, 206 patients (60%; 95% confidence interval 54% to 65%) were positive for HIV--in one or both assays used. The peaks for both tuberculosis and HIV infection were among men aged 25-34 years and women aged 14-24 years. Of patients with confirmed pulmonary tuberculosis, 73/149 (49%; 41% to 57%) were positive for HIV; 67/83 (81%; 70% to 89%) patients with pleural disease and 16/19 (84%; 60% to 97%) patients with pericardial disease were positive. HIV positive patients with positive sputum culture were less likely to have had a positive sputum smear, and their chest x ray films less often showed classic upper zone disease or cavitation. Of 72 patients who fulfilled clinical criteria for AIDS, 17 were negative for HIV. CONCLUSIONS--The high prevalence of HIV in patients with tuberculosis suggests that an epidemic of reactivating tuberculosis is arising in those who are infected with HIV. The redirection of public health priorities towards tuberculosis would focus on a major treatable and preventable complication of the AIDS epidemic.  相似文献   

14.
Tuberculosis is a frequent complication of human immunodeficiency virus (HIV)-induced immunosuppression. The diagnosis of extrapulmonary tuberculosis in patients with evidence of HIV infection qualifies as a criterion of the acquired immunodeficiency syndrome. Demographic characteristics of patients with tuberculosis and HIV infection vary by region and reflect the degree to which patients with Mycobacterium tuberculosis infection adopt behaviors that put them at risk for HIV infection. The clinical features of tuberculosis in patients with HIV infection are atypical. Extrapulmonary disease, tuberculin anergy, and unusual findings on chest radiographs occur most frequently when tuberculosis afflicts patients with other clinical evidence of HIV infection at the time tuberculosis is diagnosed. Treatment is effective for tuberculosis in HIV-seropositive patients, and isoniazid prophylaxis is recommended for HIV-infected patients with positive tuberculin skin tests.  相似文献   

15.

Background

Extrapulmonary manifestations of tuberculosis have become increasingly important in the era of HIV/AIDS.

Case presentation

We describe a case of tuberculosis (TB) dactylitis in a patient with AIDS who originated from the Ivory Coast. The diagnosis was established by direct visualization of acid-fast bacilli on joint fluid and bone biopsy of the proximal phalanx. Imaging of the chest revealed multiple bilateral nodules. Confirmation of the diagnosis was made by isolation of Mycobacterium tuberculosis from sputum and bone cultures.

Conclusion

Tuberculosis should be considered in patients with unusual soft tissue or skeletal lesions, especially when an immunosuppressive condition is present. Ziehl-Neelsen staining and culture of tissue obtained via surgical biopsy offer the most direct approach to diagnosis.  相似文献   

16.
17.
为探讨利福平耐药结核分枝杆菌实时荧光定量核酸扩增检测技术(Xpert Mycobacterium tuberculosis/rifampicin,Xpert MTB/RIF)在人类免疫缺陷病毒感染/艾滋病(human immunodeficiency virus infection/acquired immunodeficiency syndrome,HIV/AIDS)患者中诊断结核病的价值,本研究回顾性分析了2018年1月1日—2020年12月31日复旦大学附属公共卫生临床中心感染与免疫科收治的801例HIV/AIDS合并疑似结核病患者的临床资料。801例患者中,657例进行了Xpert MTB/RIF、外周血结核感染T细胞斑点试验(tuberculosis T cell spot test,T-SPOT.TB)、抗酸染色涂片镜检和BACTEC MGIT 960液体培养等检测。以液体培养及菌型鉴定结果作为结核病诊断的“金标准”,确诊结核病92例,Xpert MTB/RIF、T-SPOT.TB、抗酸染色涂片镜检在HIV/AIDS患者中诊断结核病(包括肺结核和肺外结核)的灵敏度分别为72.8%、55.4%和69.6%,特异度分别为96.8%、90.3%和84.4%,与“金标准”行一致性检验,Kappa值分别为0.719 (P<0.01)、0.430(P<0.01)和0.424(P<0.01)。Xpert MTB/RIF检测502份呼吸道样本,结果显示其诊断肺结核的灵敏度和特异度分别为66.7%和96.0%;在痰涂片阳性和阴性的患者中,Xpert MTB/RIF诊断肺结核的灵敏度分别为77.4%和35.2%,特异度分别为87.7%和 97.8%。采用Xpert MTB/RIF检测343份肺外标本,结果显示其诊断肺外结核的灵敏度和特异度分别为63.3%和95.2%。以上结果提示,Xpert MTB/RIF在HIV/AIDS患者中诊断结核病(包括肺结核和肺外结核)具有较高的灵敏度和特异度,诊断肺结核的灵敏度高于肺外结核,因此推荐将其作为HIV/AIDS患者疑似结核病的首选检测方法。  相似文献   

18.
HIV-associated nephropathy (HIVAN) is a clinicopathologic entity characterized by heavy proteinuria, absence of edema and an irreversible decline in renal function. Findings on renal biopsy include: collapsed glomerular capillaries; visceral glomerular epitheliosis; microcystic tubules; mesangial prominence; and endothelial tubuloreticular inclusions. Early in the AIDS epidemic, HIVAN was the predominant glomerular lesion observed in HIV-infected patients. It is being increasingly recognized, especially in Caucasian populations, that a variety of immune complex-mediated lesions such as membranoproliferative glomerulonephritis, proliferative glomerulonephritis and IgA nephropathy are associated with HIV infection. In this review we present two cases: one patient whose first presentation of AIDS was end-stage renal disease, who on biopsy was found to have HIVAN, and the second, who was infected with HIV, and on biopsy was found to have hepatitis C-related hepatitis C related membranoproliferative glomerulonephritis. We also review the current literature on HIVAN and HIV-associated immune complex diseases (HIVICDs). Each case illustrates an important clinical point. The first that renal disease can be the first manifestation of HIV infection and the second that HIV-infected patients may develop immune complex related renal diseases, some of which may be potentially treatable.  相似文献   

19.
Cryptococcosis is reported in adults and is often acquired immune deficiency syndrome (AIDS)-associated; however, its frequency in children is low. Based on the National Survey on Cryptococcosis conducted in Colombia, an epidemiological and clinical analysis was performed on cases of the disease observed in children less than 16 years old between 1993-2010. We found 41 affected children (2.6% prevalence) from the 1,578 surveys received. The country mean annual incidence rate was 0.017 cases/100,000 children under 16 years, while in Norte de Santander the incidence rate was 0.122 cases/100,000 (p < 0.0001). The average age of infected children was 8.4 and 58.5% were male. In 46.3% of cases, a risk factor was not identified, while 24.4% had AIDS. The most frequent clinical manifestations were headache (78.1%), fever (68.8%), nausea and vomiting (65.6%), confusion (50%) and meningeal signs (37.5%). Meningitis was the most frequent clinical presentation (87.8%). Amphotericin B was given to 93.5% of patients as an initial treatment. Positive microbiological identification was accomplished by India ink (94.7%), latex in cerebrospinal fluid (100%) and culture (89.5%). Out of 34 isolates studied, Cryptococcus neoformans var. grubii (VNI 85.3%, VNII 8.8%) was isolated in 94.1% of cases and Cryptococcus gattii (VGII) was isolated in 5.9% of cases. These data are complemented by a literature review, which overall suggests that cryptococcosis in children is an unusual event worldwide.  相似文献   

20.
A very unusual presentation of Mycobacterium tuberculosis in the parotid gland substance is described to suggest reexamination of the place of tuberculosis in the differential diagnosis of a parotid mass. In this patient, diagnosis was made postoperatively only by histologic examination of the excised specimen. When M. tuberculosis etiology is suspected, either clinically or at operation, culture confirmation should be tried, and a Mantoux test should be performed to complete the investigation.  相似文献   

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