Soft tissue abscess and lymphadenitis due to Mycobacterium avium complex as an expression of immune reconstitution inflammatory syndrome after a second scheme of highly active antiretroviral therapy

Immune reconstitution inflammatory syndrome (IRIS) is an atypical and unexpected reaction related to highly active antiretroviral therapy (HAART) in human immunodeficiency virus (HIV) infected patients. IRIS includes an atypical response to an opportunistic pathogen (generally Mycobacterium tuberculosis, Mycobacterium avium complex, cytomegalovirus and herpes varicella-zoster), in patients responding to HAART with a reduction of plasma viral load and evidence of immune restoration based on increase of CD4+ T-cell count. We reported a case of a patient with AIDS which, after a first failure of HAART, developed a subcutaneous abscess and supraclavicular lymphadenitis as an expression of IRIS due to Mycobacterium avium complex after starting a second scheme of HAART.     

Up-regulation of TLR2 and TLR4 in dendritic cells in response to HIV type 1 and coinfection with opportunistic pathogens

The ability to trigger an innate immune response against opportunistic pathogens associated with HIV-1 infection is an important aspect of AIDS pathogenesis. Toll-like receptors (TLRs) play a critical role in innate immunity against pathogens, but in HIV-1 patients coinfected with opportunistic infections, the regulation of TLR expression has not been studied. In this context, we have evaluated the expression of TLR2 and TLR4 in monocytes, plasmacytoid dendritic cells, and myeloid dendritic cells of HIV-1 patients with or without opportunistic infections. Forty-nine HIV-1-infected individuals were classified according to viral load, highly active antiretroviral therapy (HAART), and the presence or absence of opportunistic infections, and 21 healthy subjects served as controls. Increased expression of TLR2 and TLR4 was observed in myeloid dendritic cells of HIV-1 patients coinfected with opportunistic infections (without HAART), while TLR4 increased in plasmacytoid dendritic cells, compared to both HIV-1 without opportunistic infections and healthy subjects. Moreover, TLR2 expression was higher in patients with opportunistic infections without HAART and up-regulation of TLR expression in HIV-1 patients coinfected with opportunistic infections was more pronounced in dendritic cells derived from individuals coinfected with Mycobacterium tuberculosis. The results indicate that TLR expression in innate immune cells is up-regulated in patients with a high HIV-1 load and coinfected with opportunistic pathogens. We suggest that modulation of TLRs expression represents a mechanism that promotes HIV-1 replication and AIDS pathogenesis in patients coinfected with opportunistic pathogens.     

AIDS-related Mycobacterium avium infection dissemination in a patient with endobronchial lesions associated with immune reconstitution inflammatory syndrome

Highly active antiretroviral therapy (HAART) has dramatically decreased the incidence of HIV-1-associated morbidity and mortality. During the initial months of HAART, immune reconstitution inflammatory syndrome (IRIS), an adverse consequence of restoration of the pathogen-specific immune response, often occurred in terminal-stage in patients, with MAC infection the most frequently implicated in IRIS. In August 2004, a 26-year-old Japanese woman with fever and general lymphadenopathy was diagnosed with AIDS (HIV-1 RNA 5.7 x 10(5) copies/mL, CD4+ T cell count 10/microL) and disseminated Mycobacterium avium (M. avium) infection, for which antimycobacterial treatment was initiated. The M. avium infection responded well to two months of this treatment, and HAART was begun. Despite good virologic response to HAART (HIV-1 RNA <50 copies/mL), she contracted pulmonary disease with parenchymal lung changes, endobronchial lesions, and localized supraclavicular lymphadenitis, which are M. avium-associated IRIS. Good immunological response (CD4+ T cell count 136/microL) and a stronger antimycobacterial treatment helped her overcoming M. avium-associated IRIS without systemic corticosteroids or the discontinuation of HAART. The possibility of IRIS should always be watched for when treating AIDS patients with HAART and an antimycobacterial treatment regimen formulated that considers potential drug interactions with HAART.     

Epidemiology of bloodstream infections and predictive factors of mortality among HIV-infected adult patients in Thailand in the era of highly active antiretroviral therapy

Few studies have described the pattern of bloodstream infections (BSI) among HIV-infected patients in the highly active antiretroviral therapy (HAART) era, particularly in resource-limited settings. A retrospective cohort study was conducted among 140 HIV-infected patients who had a positive blood culture from 2004-2008. Of the 140 patients, 91 (65%) were male with a mean (SD) age of 38 (9.1) years and a median (IQR) CD4 cell count of 32 (9-112) cells/mm(3). Community-acquired infection was detected in 89% of patients. The blood cultures contained Gram-negative bacteria, 40%; fungi, 24%; Mycobacterium spp., 20%; and Gram-positive bacteria, 16%. Common causative pathogens were Cryptococcus neoformans, 21%; Salmonella spp., 15%; and Mycobacterium tuberculosis, 12%. Common focal sites of infection were the central nervous system, 24%; respiratory tract, 20%; and gastrointestinal tract, 18%. CD4 cell count (OR, 0.61 per 50 cells/mm(3) increment; 95% CI, 0.39-0.96; P = 0.031) was the only factor associated with mycobacterial or fungal BSI. The crude mortality was 21%. HAART (OR, 0.23; 95% CI, 0.01-0.77; P = 0.017), focal infection (OR, 0.31; 95% CI, 0.10-0.97; P = 0.044), and complication (e.g., shock) (OR, 9.26; 95% CI, 3.25-26.42; P < 0.001) were the predictive factors of mortality. In conclusion, opportunistic infections are still the leading causes of BSI among HIV-infected patients in the HAART era.     

Immune reconstitution inflammatory syndrome associated with disseminated mycobacterial infection in patients with AIDS

Restoration of the immune system after highly active antiretroviral therapy (HAART) resulting from a quantitative and qualitative process of cell immune activity recovery may evolve with adverse clinical phenomena, known as the immune reconstitution inflammatory syndrome (IRIS). It can occur in association with several opportunist infections, although most reported cases have been related to mycobacterial infection caused by Mycobacterium tuberculosis and Mycobacterium avium. We describe three clinical cases of mycobacterial infection with different presentation patterns of IRIS after HAART. In each of these patients, immune reconstitution led to clinical manifestation of a latent infection, or clinical worsening of preexisting lesions, or manifestation of new lesions in the central nervous system. Clinical aspects of IRIS are presented in the paper and clinical management options for this event are carefully discussed.     

Immunopathology as a result of highly active antiretroviral therapy in HIV-1-infected patients

OBJECTIVE: Unusual clinical inflammatory syndromes associated with underlying previously unrecognized opportunistic infections are increasingly being noted shortly after starting highly active antiretroviral therapy (HAART). This study examined the possible relationship between such unexpected disease manifestations and in vitro parameters of microbial antigen-specific immune reactivity in patients infected with HIV-1 who had a Mycobacterium avium intracellulare or Mycobacterium xenopi infection. DESIGN: In vitro T-cell proliferation experiments were performed after specific stimulation of a patient's peripheral blood mononuclear cells (PBMC) with M. avium and M. xenopi antigen and non-specific stimulation with phytohaemagglutinin (PHA). The results were compared with appropriate controls. PATIENTS: Five patients who presented with unusual clinical syndromes associated with M. avium or M. xenopi infection within weeks of experiencing large rises in CD4+ cell counts following the initiation of antiretroviral therapy. RESULTS: In all patients except one, mycobacteria-specific lymphoproliferative responses rose significantly following HAART; this was temporally associated with elevations in CD4+ cell counts and the occurrence of clinical disease. The patient with M. xenopi infection appeared to clear his infection subsequently without antimycobacterial therapy. In three of the four patients with M. avium infection, antimycobacterial treatment could be stopped without recurrence of infection. CONCLUSION: Our findings support the hypothesis that HAART may lead to clinically relevant inflammation as a result of restoration of specific immune reactivity against microbial pathogens that are subclinically present at the time treatment is initiated. Continuation of HAART may subsequently result in protective immunity and clearance of infection.     

Acute peritonitis as presentations of tuberculosis-associated immune reconstitution inflammatory syndrome in an HIV-infected man

Immune reconstitution inflammatory syndrome (IRIS) is particularly observed after the start of therapy for pathogenic antigens in patients infected with human immunodeficiency virus (HIV) and receiving highly active antiretroviral therapy (HAART). Although tuberculosis (TB)-associated IRIS is the most common form, its presentation as a primary feature of acute peritonitis is extraordinarily rare. We report a 43-year-old man diagnosed with acquired immunodeficiency syndrome and pulmonary TB coinfection. His symptoms, sputum quantity, and chest radiologic appearance improved markedly after 3 weeks of antituberculous therapy, and HAART was initiated on the fourth week. However, acute abdomen with peritoneal signs resulting from the established tuberculous peritonitis developed on the seventh day of HAART. His clinical symptoms resolved after maintenance of HAART and antituberculous regimens. Tuberculous peritonitis must be considered in the differential diagnosis of acute abdomen in HIV-infected patients on antiviral therapy, especially in patients with known underlying TB. Early recognition of IRIS is important when managing HIV-infected patients with opportunistic infections.     

Impact of highly active antiretroviral therapy on organ-specific manifestations of HIV-1 infection

In the last 10 years, interesting results have been reported concerning the impact of highly active antiretroviral therapy (HAART) on the changing pattern of organ-specific manifestations of HIV-1 infection. There has been a clear step-wise reduction in the incidence of several opportunistic infections (OIs), particularly Pneumocystis carinii pneumonia, whereas a nonsignificant reduction in incidence has been observed for other organ-specific diseases, including invasive cervical cancer and Hodgkin disease. In addition, several organ-specific manifestations, including HIV-associated nephropathy, wasting syndrome and cardiomyopathy, are a direct consequence of damage by HIV-1, and so HAART may have a therapeutic effect in improving or preventing these manifestations. Finally, the introduction of HAART has seen the emergence of several complications, termed immune reconstitution inflammatory syndrome, which includes OIs such as cytomegalovirus vitritis, Mycobacterium avium complex lymphadenitis, paradoxical responses to treatment for tuberculosis, and exacerbation of cryptococcosis. Because not all HIV-1 organ-specific manifestations are decreasing in the HAART era, this review will analyse the influence of HAART on several organ-specific manifestations, and in particular OIs related to several organs, cerebral disorders and HIV-1-related neoplasia.     

Tuberculosis immune reconstitution inflammatory syndrome in countries with limited resources.

Mycobacterium tuberculosis infection accounts for probably one third of human immunodeficiency virus (HIV) related immune reconstitution inflammatory syndrome (IRIS) events, particularly in developing countries where HIV and tuberculosis (TB) co-infection is very common. Small cohort studies of HIV-positive patients with active TB treated with antiretroviral therapy (ART) suggest an incidence of TB IRIS varying between 11% and 45%. Risk factors for TB IRIS that have been suggested in certain studies but not in others include: starting ART within 6 weeks of starting TB treatment; extra-pulmonary or disseminated disease; a low CD4+ lymphocyte count and a high viral load at the start of ART; and a good immunological and virological response during highly active antiretroviral therapy (HAART). It is important to agree on a clinical case definition of TB IRIS that could be used in resource-limited settings. Such a case definition could be used to determine the exact incidence and consequences of TB IRIS and would be valuable worldwide in clinical trials that are needed to answer questions on how this phenomenon could be prevented and treated.     

HIV感染者并发鸟-胞内复合分枝杆菌感染的防治进展

艾滋病（AIDS）发展至艾滋病期可以出现多种机会性感染,鸟-胞内分枝杆菌是播散性细菌性感染的常见原因。自从高效抗反转录病毒治疗（HAART）应用以来,鸟-胞内分枝杆菌的发生率有了实质性的减少,但是对于CD4细胞计数较低的病人仍然有一定的风险。该文就近些年来AIDS病人并发鸟-胞内复合分枝杆菌感染的流行病学、临床表现、治疗和预防进展进行综述。     

Opportunistic infections as causes of death in HIV-infected patients in the HAART era in France

The objective of the study was to describe the underlying causes of death of HIV-infected patients in the HAART era and to focus on those related to opportunistic infection (OI), in a national multicentre study ('Mortalité 2000'). A total of 964 deaths were recorded and 924 cases were available for analysis. Underlying cause of death were AIDS-related (47%), viral hepatitis (11%), non-AIDS cancers (11%), cardiovascular diseases (7%) and others (11%). Among patients who died of AIDS events, 262 (27%) died of at least one OI. OIs reported at the time of death were Cytomegalovirus infection 67 times, Pneumocystis jiroveci pneumonia 56, disseminated Mycobacterium avium intracellulare infection 53 and cerebral toxoplasmosis 48. Compared to patients who died of other causes, patients who died of OIs were younger and more likely to be infected through heterosexual contact, in poor socioeconomic conditions, migrants, more recently diagnosed for HIV infection, and naive of antiretroviral therapy and OI prophylaxis. OIs are still a major cause of death in HIV-infected patient in the HAART era, especially among patients recently diagnosed for HIV infection and who do not have access to care, as well as in long term infected patients where prophylaxis should be revisited.     

Successful administration of aggressive chemotherapy concomitant to tuberculostatic and highly active antiretroviral therapy in a patient with AIDS-related Burkitt's lymphoma

Treatment of AIDS-related malignant lymphoma (ARL) remains a therapeutic challenge. There are concerns not only about infectious and haematological complications in HIV-infected patients during intensive chemotherapy, but also about potential interactions between chemotherapy and highly active antiretroviral therapy (HAART). Current data on patients treated concomitantly with intensive chemotherapy and HAART are limited, and no data exist on patients with ARL suffering from active opportunistic infections. We report the case of a 38-year-old man with advanced HIV-1 infection, pulmonary tuberculosis and Burkitt's lymphoma. Intensive chemotherapy was administered in parallel with tuberculostatic therapy and HAART. Six months later, the patient achieved not only a complete remission of Burkitt's lymphoma and sustained viral suppression, but also a full recovery from tuberculosis. This case report provides some useful observations on the successful application of intensive chemotherapy in addition to tuberculostatic therapy and HAART in HIV-infected patients.     

Can chemoprophylaxis against opportunistic infections be discontinued after an increase in CD4 cells induced by highly active antiretroviral therapy?

BACKGROUND: In the 'USPHS/IDSA Guidelines for Prevention of Opportunistic Infections in Persons Infected with Human Immunodeficiency Virus', the indications for chemoprophylaxis are based on nadir CD4 cell count. Many patients have, however, experienced an increase in CD4 cell count after the introduction of highly active antiretroviral therapy (HAART). OBJECTIVES: To assess incidences of opportunistic infections after discontinuation of chemoprophylaxis in HIV-infected patients, who have experienced a HAART-induced increase in CD4 cell count. METHODS: The Danish guidelines for chemoprophylaxis against opportunistic infections in HIV-infected patients were revised in late 1997, allowing discontinuation of chemoprophylaxis after initiation of HAART if the CD4 cell count remained above a specified limit for more than 6 months. Consecutive patients were followed, and incidences of opportunistic infections after discontinuation of chemoprophylaxis were assessed. RESULTS: A total of 219 patients discontinued Pneumocystis carinii pneumonia (PCP)-chemoprophylaxis (12% maintenance therapy). One case of PCP was diagnosed within 174 person-years (PY) of follow-up, resulting in an incidence of 0.6 cases/100 PY follow-up (95% confidence interval, 0.0-3.2). No cases of cerebral toxoplasmosis, cytomegalovirus chorioretinitis, or disseminated Mycobacterium avium infection were observed. Follow-up time for these was, however, limited. CONCLUSION: PCP-chemoprophylaxis can be safely discontinued after HAART-induced increase in CD4 cell count to more than 200 x 10(6) cells/l. Among consecutive patients who discontinue chemoprophylaxis according to well-defined guidelines, the observed incidence of PCP is below those reported earlier in patients with similar CD4 cell count.     

Pulmonary complications of immune reconstitution inflammatory syndromes in HIV-infected patients

Immune reconstitution inflammatory syndrome (IRIS) describes a paradoxical worsening of clinical status related to recovery of the immune system, as can occur after the initiation of highly active antiretroviral therapy (HAART) in HIV-infected patients. Most commonly, IRIS results from opportunistic infections that can unmask or develop paradoxical worsening following HAART. Cancers, autoimmune conditions and sarcoidosis have also been associated with IRIS. Pulmonary complications may be frequently encountered. This article reviews the types and clinical presentation of IRIS, with a focus on the pulmonary manifestations. Management and outcome of IRIS are considered.     

HIV/AIDS患者免疫重建炎性综合征的诊治

免疫重建炎性综合征（immune reconstitution inflammatory syndrome,IRIS）是部分HIV／AIDS患者在高效抗反转录病毒治疗后发生的一组疾病。IRIS主要与机体在免疫功能恢复过程中产生了针对残存活性／非活性抗原的过度免疫炎症反应以及免疫调节功能的缺失有关。临床多表现为抗病毒治疗后已有疾病的恶化或出现新发疾病。IRIS相关的感染原多见于分枝杆菌、新型隐球菌、巨细胞病毒等,临床上因特异性感染原的不同而表现各异。早期诊断、及时治疗IRIS,对更好地开展AIDS的抗病毒治疗非常重要。     

Tuberculosis in HIV-infected persons in the context of wide availability of highly active antiretroviral therapy.

Highly active antiretroviral therapy (HAART) greatly reduces the risk of developing tuberculosis for HIV-infected persons. Nonetheless, HIV-associated tuberculosis continues to occur in countries where HAART is widely used. To identify the characteristics of HIV-infected persons who develop tuberculosis in the context of the availability of HAART, the current authors analysed data taken from 271 patients diagnosed, in Italy, during 1999-2000. These patients represent 0.7% of the 40,413 HIV-infected patients cared for in the clinical units participating in this current study. From the data it was observed that 20 patients (7.4%) had a previous episode of tuberculosis whose treatment was not completed. Eighty-one patients (29.9%) were diagnosed with HIV at tuberculosis diagnosis, 108 (39.8%) were aware of their HIV status but were not on antiretroviral treatment and 82 (30.3%) were on antiretroviral treatment. Patients on antiretroviral treatment were significantly less immunosuppressed than patients with HIV diagnosed concurrently with tuberculosis, or other patients not on antiretrovirals (median CD4 lymphocytes count: 220 cells x mm(-3) versus 100 cells x mm(-3), and 109 cells x mm(-3), respectively). No significant differences in clinical presentation of tuberculosis according to antiretroviral therapy status were recorded. Failure of tuberculosis control interventions (e.g. noncompletion of treatment) and of HIV care (delayed diagnosis of HIV infection and suboptimal uptake of therapy) may contribute to continuing occurrence of HIV-associated tuberculosis in a country where highly active antiretroviral therapy is largely available. However, a significant proportion of cases occur in patients who are on antiretroviral treatment.     

Evolution of the incidence and aetiology of fever of unknown origin (FUO), and survival in HIV-infected patients after HAART (Highly Active Antiretroviral Therapy)

BackgroundFever of unknown origin (FUO) is common among HIV-infected patients with a CD4+ T-lymphocyte cell count below 200 cells/ml. The use of HAART has transformed the evolution of AIDS and related diseases.Design and methodCase-control study, nested on a historical cohort of 3777 HIV-infected patients who were attended at “12 de Octubre” University Hospital in Madrid, Spain, between 1994 and 2000.Results276 FUO episodes were recorded, 58 of which occurred in patients receiving HAART. The significant decrease on the accumulated FUO incidence along the study period of 7.3 episodes per 100 HIV-infected patients after 1997 corresponded with the introduction of HAART. FUO was more frequent in patients who did not receive HAART. The aetiological spectrum of FUO was transformed by the introduction of HAART: the incidence of tuberculosis decreased while that of leishmaniasis increased. The four year survival in the non-FUO group increased when compared to that of patients who had had FUO. Similarly, this four year survival increased in patients who received HAART at the time of FUO versus those not receiving it.ConclusionsOur results confirm that the incidence of FUO has significantly decreased with the introduction of HAART. HAART has also transformed the aetiological spectrum related to FUO considerably. The most frequent cause of FUO in non-HAART patients on this study was the disseminated infection by Mycobacterium avium intracellulare (MAI), followed by tuberculosis, while leishmaniasis was its most common cause in patients receiving HAART. Survival decreased in patients who developed FUO; however, patients who received HAART at the time of FUO had longer survival than patients who did not.     

HIV1 and the gut in the era of highly active antiretroviral therapy

The gut and its gut-associated lymphoid tissue serve as a preferential site for HIV1 entry, active viral replication, reservoir, and HIV-mediated CD4 cell apoptosis. The widespread use of highly active antiretroviral therapy (HAART) has resulted in a significant decrease in the incidence of opportunistic enteric pathogens as a consequence of immune recovery. Nonetheless, patients with advanced HIV1 disease who were recently diagnosed or have poor response to HAART can still suffer from opportunistic infections with pathogens such as Cryptosporidium, microsporidia, Isospora belli, Cyclospora cayetanensis, Mycobacterium avium complex, and cytomegalovirus, among others. This review describes the impact of HIV1 infection on gut immune function, the salient features of the most common opportunistic enteric pathogens and HIV-associated enteropathy, and the effects of immune reconstitution after introduction of HAART.     

Mycobacterium avium complex in patients with HIV infection in the era of highly active antiretroviral therapy

Disseminated Mycobacterium avium complex (MAC) infection is a common complication of late-stage HIV-1 infection. Since the advent of highly active antiretroviral therapy (HAART), the rate of MAC infection has declined substantially, but patients with low CD4 cell counts remain at risk. Among patients in the Johns Hopkins cohort with advanced HIV disease, the proportion developing MAC has fallen from 16% before 1996 to 4% after 1996, with a current rate of less than 1% per year. Factors associated with developing MAC include younger age, no use of HAART, and enrollment before 1996. Prophylaxis with azithromycin or clarithromycin is recommended for all patients with CD4 counts less than 50 cells/mL. Optimum treatment for disseminated MAC includes clarithromycin and ethambutol, and another investigation suggests that the addition of rifabutin might reduce mortality. Both prophylaxis and treatment of disseminated MAC can be discontinued in patients who have responded to HAART, and specific guidelines for withdrawing treatment have been published. Although HAART has altered the frequency and outcome of MAC infection, it remains an important complication of AIDS.