Pathogenesis and prevention of immune reconstitution disease during antiretroviral therapy

Integrase inhibitors: current protagonists in antiretroviral therapy

Since HIV was identified as the etiological agent of AIDS, there have been significant advances in antiretroviral therapy (ART) that has reduced morbidity/mortality. Still, the viral genome's high mutation rate, suboptimal ART regimens, incomplete adherence to therapy and poor control of the viral load generate variants resistant to multiple drugs. Licensing over 30 anti-HIV drugs worldwide, including integrase inhibitors, has marked a milestone since they are potent and well-tolerated drugs. In addition, they favor a faster recovery of CD4+ T cells. They also increase the diversity profile of the gut microbiota and reduce inflammatory markers. All of these highlight the importance of including them in different ART regimens.

Mesenchymal Stromal Cells: an Antimicrobial and Host-Directed Therapy for Complex Infectious Diseases

There is an urgent need for new antimicrobial strategies for treating complex infections and emerging pathogens. Human mesenchymal stromal cells (MSCs) are adult multipotent cells with antimicrobial properties, mediated through direct bactericidal activity and modulation of host innate and adaptive immune cells. More than 30 in vivo studies have reported on the use of human MSCs for the treatment of infectious diseases, with many more studies of animal MSCs in same-species models of infection. MSCs demonstrate potent antimicrobial effects against the major classes of human pathogens (bacteria, viruses, fungi, and parasites) across a wide range of infection models. Mechanistic studies have yielded important insight into their immunomodulatory and bactericidal activity, which can be enhanced through various forms of preconditioning. MSCs are being investigated in over 80 clinical trials for difficult-to-treat infectious diseases, including sepsis and pulmonary, intra-abdominal, cutaneous, and viral infections. Completed trials consistently report MSCs to be safe and well tolerated, with signals of efficacy against some infectious diseases. Although significant obstacles must be overcome to produce a standardized, affordable, clinical-grade cell therapy, these studies suggest that MSCs may have particular potential as an adjunct therapy in complex or resistant infections.

Association of CD4 T cell count and optimal timing of antiretroviral therapy initiation with immune reconstitution inflammatory syndrome and all-cause mortality for HIV-infected adults with newly diagnosed pulmonary tuberculosis: a systematic review and meta-analysis

AIMS

CD4 T cell count and optimal timing of antiretroviral therapy (ART) during tuberculosis (TB) treatment are challenging. We conducted a meta-analysis to assess the association of CD4 T cell count and timing of ART initiation with immune reconstitution inflammatory syndrome (IRIS) and all-cause mortality of patients co-infected with HIV/TB.

METHODS

We conducted an electronic search of clinical studies dated from January 1980 to December 2019 in PubMed and EMBASE. Randomized, controlled trials evaluating low-base CD4 T cell count (< 50 cells/μL) versus high-base CD4 T cell count (≥ 50 cells/μL), and/or early ART initiation (1 to 28 days after starting TB treatment) versus delayed ART initiation (≥ 28 days after starting TB treatment) were included. The primary endpoints were all-cause mortality and TB-related immune reconstitution inflammatory syndrome (IRIS-TB). The risk ratio (RR) was calculated as a measure of intervention effect. Mantel-Haenszel method was used to estimate the RR.

RESULTS

Ten trials (n = 5226) were conducted in North America, Africa, and Asia. We found that low-baseline CD4 T cell count increased the incidence of TB-associated IRIS (RR, 1.47; 95% CI, 1.24-1.75; I² = 58%) and all-cause mortality (RR, 2.42; 95% CI, 1.71-3.42; I² = 41%) compared with high baseline CD4 T cell count, and early ART initiation increased the incidence of TB-associated IRIS compared with delayed ART initiation (RR, 1.80; 95% CI, 1.57-2.07; I² = 74%). However, early ART initiation did not reduce all-cause mortality (RR, 0.91; 95% CI, 0.74-1.12; I² = 49%) compared with delayed ART initiation.

CONCLUSIONS

The present study demonstrates that low-baseline CD4 T cell count (< 50 cells/μL) in patients co-infected with TB-HIV increases the incidence of TB-associated IRIS and all-cause mortality. Early ART initiation (≤ 28 days) in patients co-infected with TB-HIV increases the incidence of TB-associated IRIS. However, evidence is insufficient to refute or support a survival benefit conferred by the comparison between early ART initiation (≤ 28 days) and delayed ART initiation.

Lack of elevated pre-ART elastase-ANCA levels in patients developing TB-IRIS

Background

Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) in HIV-TB co-infected patients receiving antiretroviral therapy (ART) has been linked to neutrophil activation. Anti-neutrophil cytoplasmic antibodies (ANCAs) are also associated with neutrophil activation. Since ANCAs are reportedly skewed in TB and HIV infections, we investigated plasma levels of 7 ANCAs in TB-IRIS patients.

Methods

We retrospectively compared 17 HIV-TB patients who developed TB-IRIS with controls of similar CD4 count, age and gender who did not (HIV⁺TB⁺ n = 17), HIV-infected patients without TB (HIV⁺TB^-, n = 17) and 10 HIV-negative (HIV^-TB^-) controls. Frozen plasma was collected before ART, at 3 and 9 months of ART, and examined by ELISA for levels of 7 ANCAs directed against; Proteinase 3 (PR3), Myeloperoxidase (MPO), Permeability-increasing protein (BPI), Elastase, Cathepsin, Lysozyme, and Lactoferrin.

Results

Compared to HIV⁺TB⁺ controls, pre-ART anti-elastase levels were lower in TB-IRIS patients (p = 0.026) and HIV^-TB^- controls (p = 0.044), whereas other ANCAs did not show significant differences between groups at any time point. A significant decrease over time could be observed in TB-IRIS patients during ART for anti -PR3 (p = 0.027), -lysozyme (p = 0.011), and -lactoferrin (p = 0.019). Conversely, HIV⁺TB⁺ controls showed a significant decrease over time for anti -MPO (p = 0.002), -lyzosyme (p = 0.002) and -elastase (p < 0.001).

Conclusion

The lack of elevated anti-elastase levels in TB-IRIS patients as opposed to HIV⁺TB⁺ controls correspond to previous findings of lowered immune capacity in patients that will develop TB-IRIS. This may suggest a specific role for anti-elastase, elastase or even matrix-metalloproteinases in TB-IRIS. The precise dynamics of neutrophil activation in HIV-TB merits further investigation and could provide more insight in the early mechanisms leading up to TB-IRIS.

Pathogenesis of Human Immunodeficiency Virus-Mycobacterium tuberculosis Co-Infection

Given that infection with Mycobacterium tuberculosis (Mtb) is the leading cause of death amongst individuals living with HIV, understanding the complex mechanisms by which Mtb exacerbates HIV infection may lead to improved treatment options or adjuvant therapies. While it is well-understood how HIV compromises the immune system and leaves the host vulnerable to opportunistic infections such as Mtb, less is known about the interplay of disease once active Mtb is established. This review explores how glutathione (GSH) depletion, T cell exhaustion, granuloma formation, and TNF-α upregulation, as a result of Mtb infection, leads to an increase in HIV disease severity. This review also examines the difficulties of treating coinfected patients and suggests further research on the clinical use of GSH supplementation.

TB-IRIS pathogenesis and new strategies for intervention: Insights from related inflammatory disorders

In almost one in five HIV/tuberculosis (TB) co-infected patients, initiation of antiretroviral therapy (ART) is complicated by TB immune reconstitution inflammatory syndrome (TB-IRIS). Corticosteroids have been suggested for treatment of severe cases, however no therapy is currently licensed for TB-IRIS. Hence, there is a strong need for more specific therapeutics, and therefore, a better understanding of TB-IRIS pathogenesis. Immune reconstitution following ART is a precariously balanced functional restoration of adaptive immunity. In those patients predisposed to disease, an incomplete activation of the innate immune system leads to a hyper-inflammatory response that comprises partially overlapping innate, adaptive and effector arms, eventually leading to clinical symptoms. Interestingly, many of these pathological mechanisms are shared by related inflammatory disorders. We here describe therapeutic strategies that originate from these other disciplines and discuss their potential application in TB-IRIS. These new avenues of interventions range from final-phase treatment of symptoms to early-phase prevention of disease onset. In conclusion, we propose a novel approach for the discovery and development of therapeutics, based on an updated model of TB-IRIS pathogenesis. Further experimental studies validating the causal relationships in the proposed model could greatly contribute to providing a solid immunological basis for future clinical trials on TB-IRIS therapeutics.

Effects of physical exercises on inflammatory biomarkers and cardiopulmonary function in patients living with HIV: a systematic review with meta-analysis

BACKGROUND

Pro-inflammatory cytokines expressed in human immune deficiency virus (HIV) infection, may induce oxidative stress likely to compromise the patency of the airways or damage the lung tissues/cardiac function. However, physical (aerobic and/or resistance) exercise-induced release of heat shock protein, immune function alteration or reduced tissue hypoxia, have been highlighted as possible mechanisms by which increasing physical activity may reduce plasma pro-inflammatory cytokines in uninfected individuals and should be appraised in the literature for evidence of similar benefits in people living with HIV (PLWH). Therefore, we evaluated the effects of physical exercises on 1) inflammatory biomarkers and 2) cardiopulmonary function (VO2 Max) in PLWH.

METHOD

A systematic review was conducted using the Cochrane Collaboration protocol. Searching databases, up to January 2018. Only randomized control trials investigating the effects of either aerobic or resistance or a combination of both exercise types with a control/other intervention(s) for a period of at least 4 weeks among adults living with HIV, were included. Two independent reviewers determined the eligibility of the studies. Data were extracted and risk of bias (ROB) was assessed with the Cochrane Collaboration ROB tool. Meta-analyses were conducted with random effect models using the Review Manager (RevMan) computer software.

RESULT

Twenty-three studies met inclusion criteria (n = 1073 participants at study completion) comprising male and female with age range 18-65 years. Three meta-analyses across three sub-groups comparisons were performed. The result showed no significant change in biomarkers of inflammation (IL-6 and IL-1β) unlike a significant (Z = 3.80, p < 0.0001) improvement in VO2 Max. Overall, the GRADE evidence for this review was of moderate quality.

CONCLUSION

There was evidence that engaging in either aerobic or resistance exercise, or a combination of both exercises, two to five times per week can lead to a significant improvement in cardiopulmonary function but not biomarkers of inflammation (IL-6 and IL-1β). However, this should not be interpreted as "No evidence of effect" because the individual trial studies did not attain sufficient power to detect treatment effects. The moderate grade evidence for this review suggests that further research may likely have an important impact on our confidence in the estimate of effects and may change the estimate.

Increased KLRG1 and PD-1 expression on CD8 T lymphocytes in TB-IRIS

Background

Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) is an inflammatory complication in HIV-TB co-infected patients receiving antiretroviral therapy (ART). The exact contribution of T cells, natural killer (NK) cells, and monocytes to TB-IRIS development remains unclear. Here, we studied the expression of exhaustion markers on lymphocytes at different intervals during ART.

Methods

We compared 13 HIV-TB patients who developed TB-IRIS with 13 patients who did not (HIV⁺TB⁺), 13 HIV-patients without TB (HIV⁺TB^-) and 9 HIV/TB-negative controls (HIV^-TB^-). Patients did not differ in age, gender, or CD4-count prior to ART. Frozen peripheral blood mononuclear cells, collected before ART and during 3 months and 9 months of ART, were analysed using flow cytometry. We examined expression of KLRG1, PD-1 and IL-27R on CD4⁺ and CD8^hi T cells, as well as CD3-negative CD8^lo lymphocytes as an approximate subset of NK cells. In addition, expression of TLR2, TLR4, IL1RL1, and TRAILR on CD14⁺ monocytes were investigated.

Results

Prior to ART, TB-IRIS patients had higher percentages of CD8^hi T cells that are KLRG1⁺PD-1⁺ compared to each control group (p≤0.034). Though PD-1 expression decreased during ART in all groups (p≤0.026), the percentage KLRG1⁺PD-1⁺CD8^hi T cells remained higher in TB-IRIS patients after 3 months of ART (p≤0.013). Though these patterns were less pronounced in CD3^-CD8^lo lymphocytes, the percentage of KLRG1⁺ cells was higher in TB-IRIS patients prior to ART (p≤0.043). In contrast, no clear differences could be observed for CD4⁺ T cells or monocytes.

Conclusion

TB-IRIS is preceded by a high level of exhausted (KLRG1⁺PD-1⁺) CD8^hi T cells, which persists during 3 months of ART. This trait is potentially mirrored in a subpopulation of NK cells, but not CD4⁺ T cells. Since a dysfunctional CD8⁺ lymphocyte compartment could predispose patients to TB-IRIS, the functional role of these cells prior to TB-IRIS development should be further explored.

Aberrant plasma MMP and TIMP dynamics in Schistosoma - Immune reconstitution inflammatory syndrome (IRIS)

Background

Among the different faces of immune reconstitution inflammatory syndrome (IRIS) developing in HIV-patients, no clinical definition has been reported for Schistosomiasis-IRIS (Schisto-IRIS). Although Schisto-IRIS remains largely uninvestigated, matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMP) have previously been associated with S. mansoni infection and tuberculosis-IRIS. Here, we aimed to investigate the relevance of these markers in Schisto-IRIS.

Methodology

Patients were diagnosed with IRIS related to S. mansoni within a cohort of patients with Schistosomiasis-HIV co-infection, using a clinical working definition of Schisto-IRIS. We compared 9 patients who developed Schisto-IRIS to 9 Schisto⁺HIV⁺ controls who did not, and 9 Schisto^-HIV⁺ controls. Plasma levels of MMP-1, MMP-7, MMP-10, TIMP-1, TIMP-2, sCD14, intestinal fatty-acid binding protein, C-reactive protein, and 8 anti-nuclear antibodies (ANA) were analyzed prior to and during 3 months of ART.

Principal findings

Although no differences were observed for MMP-1 and -7, MMP-10 levels decreased significantly in Schisto⁺HIV⁺ controls during 3 months of ART (p = 0.005) while persisting in Schisto-IRIS patients at significantly higher levels compared to Schisto^-HIV⁺ controls (p≤0.030). In contrast TIMP-1 levels only decreased significantly in Schisto-IRIS patients (p = 0.012), while TIMP-2 levels were lower compared to Schisto⁺HIV⁺ controls at 2 weeks (p = 0.007), 1 month (p = 0.005) and 3 months (p = 0.031) of ART. Five out of 8 ANAs studied decreased significantly in Schisto-IRIS patients after 1 month of ART(p≤0.039), whereas only 1 ANA decreased for Schisto⁺HIV⁺ controls (p = 0.027).

Conclusions/Significance

In this study, we propose a working definition for the diagnosis of Schisto-IRIS in resource limited settings. We report persistent plasma levels of MMP-10, along with a more pronounced decrease in TIMP-1 and ANA-levels, and low levels of TIMP-2 during 3 months of ART. Corresponding to the clinical symptoms, these data suggest that Schisto-IRIS is marked by unbalanced MMP/TIMP dynamics which favor inflammation.

A subset of HIV-patients starting antiretroviral therapy are at risk of developing immune-driven worsening symptoms of a previously treated opportunistic infection. This paradoxical immune reconstitution inflammatory syndrome (IRIS) has been abundantly described in common co-infections such as M. tuberculosis (TB-IRIS), whereas IRIS associated with Schistosoma mansoni (Schisto-IRIS) is less well studied. Nonetheless, HIV and S. mansoni are highly co-endemic in Sub-Saharan Africa and the considerable clinical burden of Schisto-IRIS in the field should not be underestimated. Moreover, no clinical definition exists to help diagnose this complication. Although little is known about the immune dysregulation in Schisto-IRIS, matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMPs) have been linked to schistosomiasis and TB-IRIS on account of their role in tissue-destructive inflammation. The current study is nested within a three-month case-control study in schistosomiasis/HIV co-infected fishermen starting ART in Kenya. We propose a clinical working definition for Schisto-IRIS, based on critical evaluation of symptoms developing during ART. Our study now links aberrant dynamics of MMPs and TIMPs to Schisto-IRIS as well. Given the role of MMPs and TIMPs in tissue remodeling and inflammation, our findings suggest that Schisto-IRIS is marked by unbalanced MMP/TIMP dynamics that favor inflammation.

Triad of the Ischemic Cardiovascular Disease in People Living with HIV? Association Between Risk Factors, HIV Infection, and Use of Antiretroviral Therapy

PURPOSE OF REVIEW

This review is focused on cardiovascular risk factors in HIV-infected people.

RECENT FINDINGS

Antiretroviral therapy (ART) has significantly increased the life expectancy of HIV-infected people. Thus, this population has experienced non-HIV-related diseases, mainly cardiovascular diseases. Thus, in our review, we intend to understand the cardiovascular risk factors that trigger this situation. We have demonstrated that both ART and traditional cardiovascular risk factors contribute to the development of cardiovascular disease in HIV-infected people. Thus, it becomes important to stratify the risk factors to reduce this scenario.

HIV-Associated Psoriasis

Human immunodeficiency virus (HIV) prevalence is increasing worldwide as people on antiretroviral therapy are living longer. These patients are often susceptible to debilitating inflammatory disorders that are frequently refractory to standard treatment. Psoriasis is a systemic inflammatory disorder, associated with both physical and psychological burden, and can be the presenting feature of HIV infection. In this population, psoriasis tends to be more severe, to have atypical presentations and higher failure rates with the usual prescribed treatments. Management of moderate and severe HIV-associated psoriasis is challenging. Systemic conventional and biologic agents may be considered, but patients should be carefully followed up for potential adverse events, like opportunist infections, and regular monitoring of CD4 counts and HIV viral loads.

Prior to Peripheral Tolerance, Newly Generated CD4 T Cells Maintain Dangerous Autoimmune Potential: Fas- and Perforin-Independent Autoimmunity Controlled by Programmed Death-1

Lymphopenia can result from various factors, including viral infections, clinical interventions, or as a normal property of the fetal/neonatal period. T cells in a lymphopenic environment undergo lymphopenia-induced proliferation (LIP) to fill the available “niche” as defined by peptide–MHC and homeostatic cytokine resources. We recently reported systemic autoimmunity following reconstitution of the lymphoid compartment of Rag1^−/− mice with PD-1^−/− hematopoietic stem cells or by transfer of thymocytes, but not splenocytes, suggesting that programmed death-1 (PD-1) plays a crucial role in controlling recent thymic emigrants (RTE) and preventing autoimmunity upon their LIP. However, it is unclear whether RTE residing within the periphery of a lymphoreplete host maintain enhanced autoimmune generating potential or if this property only manifests if RTE experience a lymphopenic periphery immediately after export from the thymus. Furthermore, it is unclear which of a variety of T cell effector mechanisms generate pathology when control of RTE by PD-1 is lacking. Herein, we determined that PD-1 is upregulated on CD4 T cells undergoing the natural LIP characteristic of the neonatal period. Newly generated T cells lacking PD-1 maintained an enhanced autoimmune potential even after residence in a lymphoreplete periphery, emphasizing the importance of PD-1 in the establishment of peripheral tolerance. Neither Fas nor perforin-dependent killing mechanisms were required for autoimmunity, while host MHC-II expression was critical, suggesting that LIP-driven autoimmunity in the absence of PD-1 may primarily result from a CD4 T cell-mediated systemic cytokinemia, a feature potentially shared by other autoimmune or inflammatory syndromes associated with immune reconstitution and LIP.

PD-1 Controls Tonic Signaling and Lymphopenia-Induced Proliferation of T Lymphocytes

Recovery of the T lymphocyte compartment within a lymphopenic host by lymphopenia-induced proliferation (LIP) is regulated by inter- and intraclonal competition for limited resources, including homeostatic cytokines and peptide:MHC (pMHC) complexes with which the TCR can interact at least weakly to yield a tonic signal. Importantly, the process of LIP can synergize with other factors that promote T cell activation to drive inflammatory disease. While reconstitution of the lymphoid compartment of immune deficient Rag^-/- mice by transfer of wild-type hematopoietic stem cells (HSC) does not generally result in an overt disease phenotype, transfer of HSC deficient in expression of the co-inhibitory molecule PD-1 results in severe systemic autoimmunity driven by newly generated T cells that emerge from the thymus into the periphery and undergo LIP. Importantly, autoimmunity does not appear to depend on a response to exogenous (i.e., gut flora-derived) antigens. PD-1 is well known to be upregulated during T cell activation in response to cognate antigens, but it is unclear whether PD-1 has a role in controlling LIP of T cells in the absence of cognate antigen, i.e., in response to tonic pMHC. We examined whether PD-1 controls LIP of newly generated T cells by controlling the response to tonic pMHC or the homeostatic cytokine IL-7. We found that PD-1-deficient T cells have a proliferative advantage over WT T cells during LIP and this effect is MHC-II dependent and independent of IL-7Rα signaling. Furthermore, our data suggest that signals through IL-7Rα can be dispensable for LIP and may instead be of increased importance for T cell survival in conditions of high competition for limited pMHC (e.g., post-LIP, in a lymphoreplete host). We hypothesize that autoimmunity post-PD-1^-/- HSC transplant is the result of an overzealous T cell response to normally tonic self-pMHC precipitated by the synergy of LIP and PD-1 deficiency. Furthermore, potentiation of TCR signals in response to normally tonic self-pMHC may contribute to the success of PD-1 blockade in cancer immunotherapy.

An HIV-positive Case of Obstructive Jaundice Caused by Immune Reconstitution Inflammatory Syndrome of Tuberculous Lymphadenitis Successfully Treated with Corticosteroids

A 60-year-old man was admitted to our hospital because of a persistent fever with enlargement of multiple lymph nodes in the mediastinum and around the pancreatic head. He was diagnosed with tuberculosis and human immunodeficiency virus infection. We started antiretroviral therapy three weeks after the initiation of anti-tuberculous therapy. Two weeks later, jaundice appeared with dilatation of the biliary tract due to further enlargement of the lymph nodes, which seemed to be immune reconstitution inflammatory syndrome (IRIS). The administration of corticosteroids resolved the obstructive jaundice without surgical treatment or endoscopic drainage. Obstructive jaundice caused by IRIS should first be treated with corticosteroids before invasive treatment.

Tuberculous Meningitis in Children and Adults: New Insights for an Ancient Foe

PURPOSE OF REVIEW

Tuberculous meningitis is the most devastating manifestation of infection with Mycobacterium tuberculosis and represents a medical emergency. Approximately one half of tuberculous meningitis patients die or suffer severe neurologic disability. The goal of this review will be to review the pathogenic, clinical, and radiologic features of tuberculous meningitis and to highlight recent advancements in translational and clinical science.

RECENT FINDINGS

Pharmacologic therapy includes combination anti-tuberculosis drug regimens and adjunctive corticosteroids. It is becoming clear that a successful treatment outcome depends on an immune response that is neither too weak nor overly robust, and genetic determinants of this immune response may identify which patients will benefit from adjunctive corticosteroids. Recent clinical trials of intensified anti-tuberculosis treatment regimens conducted in Indonesia and Vietnam, motivated by the pharmacologic challenges of treating M. tuberculosis infections of the central nervous system, have yielded conflicting results regarding the survival benefit of intensified treatment regimens. More consistent findings have been observed regarding the relationship between initial anti-tuberculosis drug resistance and mortality among tuberculous meningitis patients. Prompt initiation of anti-tuberculosis treatment for all suspected cases remains a key aspect of management. Priorities for research include the improvement of diagnostic testing strategies and the optimization of host-directed and anti-tuberculosis therapies.

Prevalence of cryptococcal infection among advanced HIV patients in Argentina using lateral flow immunoassay

BACKGROUND

Globally, Latin America ranks third among regions with most cases of AIDS related cryptococcal meningitis. In 2009, a lateral flow immunoassay (LFA) for the detection of cryptococcal antigen (CrAg) was developed as a potential point-of-care test for diagnosis of cryptococcal infection. In 2011 World Health Organizations recommended on CrAg screening for HIV positive persons with CD4 below 100 cells/μL, followed by preemptive fluconazole treatment. However, in Argentina no formal recommendations for CrAg screening have been issued.

METHODS

HIV positive patients > = 18 years with advanced immunosuppression (CD4 counts ≤100 cells/μL within 3 months or WHO stage III/IV), who visited the hospital between April 1, 2014 and January 31, 2015, were included. The LFA was performed according to the manufacturer's instructions on all serum samples. When CrAg detection was positive, a lumbar puncture was performed to rule out cryptococcal meningitis. Patients without evidence of meningeal involvement were treated with preemptive oral fluconazole in ambulatory care.

RESULTS

We included 123 patients. Prevalence of CrAg-positivity was 8.1%. Among the 10 CrAg-positive patients, 6 had meningeal involvement detected through the CSF analysis (CSF India-ink testing, CSF CrAg and culture). The remaining 4 patients with positive CrAg received targeted preemptive treatment with oral fluconazole and were free of cryptococcal disease during the follow-up period. None of the 113 patients with a negative CrAg test result developed cryptococcal disease.

CONCLUSIONS

This is the first study in Argentina, to our knowledge, describing the prevalence of cryptococcosis and usefulness of CrAg screening. LFA provided early diagnosis to determine a high prevalence of CrAg in our hospital, and that screening for subclinical infection with preemptive antifungal treatment, prevented a substantial proportion of meningeal disease.

Immune Reconstitution Inflammatory Syndrome (IRIS): What pathologists should know

Antiretroviral therapy has significantly improved the quality and length of life for those patients able to access effective and sustained treatment. The resulting restoration of the immune response is associated with a change in the clinical presentation of opportunistic infections, and the histologic reaction to pathogens. A complex combination of alterations in host response across the stages of HIV infection has been documented over the past 3 decades. The defects are seen in both acute and chronic phases of inflammation and involve innate and adaptive immunity. In advanced stages of HIV infection, the marked disruption of lymphoid tissue and loss of follicular dendritic cells limits the host's ability to process antigen and mount specific responses to pathogens. There are qualitative and quantitative defects in CD4 T cells due to HIV infection. The resulting indirect effects include loss of cytokine production, dysregulation of B-cell function, loss of cellular mediated immunity and "holes" in the immunologic repertoire that may not be restored with the use of antiretroviral therapy. Immune reconstitution allows the host to respond to and control infection, but a significant number of patients will have atypical inflammatory syndromes during the recovery period. We briefly discuss the impact of HIV infection on the immune system and give an overview of the spectrum of conditions attributed to the Immune Reconstitution Inflammatory syndrome (IRIS).

Current trends and intricacies in the management of HIV-associated pulmonary tuberculosis

Human immunodeficiency virus (HIV) epidemic has undoubtedly increased the incidence of tuberculosis (TB) globally, posing a formidable global health challenge affecting 1.2 million cases. Pulmonary TB assumes utmost significance in the programmatic perspective as it is readily transmissible as well as easily diagnosable. HIV complicates every aspect of pulmonary tuberculosis from diagnosis to treatment, demanding a different approach to effectively tackle both the diseases. In order to control these converging epidemics, it is important to diagnose early, initiate appropriate therapy for both infections, prevent transmission and administer preventive therapy. Liquid culture methods and nucleic acid amplification tests for TB confirmation have replaced conventional solid media, enabling quicker and simultaneous detection of mycobacterium and its drug sensitivity profile Unique problems posed by the syndemic include Acquired rifampicin resistance, drug-drug interactions, malabsorption of drugs and immune reconstitution inflammatory syndrome or paradoxical reaction that complicate dual and concomitant therapy. While the antiretroviral therapy armamentarium is constantly reinforced by discovery of newer and safer drugs every year, only a few drugs for anti tuberculosis treatment have successfully emerged. These include bedaquiline, delamanid and pretomanid which have entered phase III B trials and are also available through conditional access national programmes. The current guidelines by WHO to start Antiretroviral therapy irrespective of CD4+ cell count based on benefits cited by recent trials could go a long way in preventing various complications caused by the deadly duo. This review provides a consolidated gist of the advancements, concepts and updates that have emerged in the management of HIV-associated pulmonary TB for maximizing efficacy, offering latest solutions for tackling drug-drug interactions and remedial measures for immune reconstitution inflammatory syndrome.

A little-known relationship between immune recovery syndrome and herpes zoster

Following anti-retroviral therapy (ART) or highly active antiretroviral therapy, there is an increased response to latent infections such as herpes zoster, which may lead to their reactivation. This is a result of improved immunity brought about by ART, also termed immune recovery syndrome. A 75-year-old male patient arrived at our institute with widespread vesicles and scabs on the right half of his face and oral cavity, suggesting the involvement of the trigeminal nerve. The patient had a history of being on ART two months earlier and a history of tooth extraction eight days prior to his arrival at our institute. The incidence of human immunodeficiency virus (HIV)-positive cases amongst herpes zoster cases is high, and these patients become susceptible to infections following ART. Therefore, regardless of the presence of risk factors, every herpes zoster patient should be tested for HIV infection, and high anti-retroviral therapy should be commenced/reinstituted as soon as possible. In addition, the treating physician should maintain a high level of vigilance for the patient during the first few months of ART, the peak incidence of immune recovery inflammatory disease.

Non-linear resistance training reduces inflammatory biomarkers in persons living with HIV: A randomized controlled trial

The purpose of this study is to analyse the effect of 12 weeks of non-linear resistance training (NLRT) on anthropometry, muscle strength and inflammatory biomarkers in persons infected with human immunodeficiency virus (PIHIV). Thirty previously sedentary PIHIVs were randomized into the NLRT (n = 15) and control (CON, n = 15) groups. NLRT group were submitted to 12 weeks of training, whereas the CON group maintained their daily habits. At baseline and after 12 weeks, both groups underwent anthropometric evaluations and blood sampling for the analysis of inflammatory biomarkers. Analysis of covariance using preintervention values as covariate was performed to determine the effects of exercise on anthropometry, muscle strength, cytokines levels and T cells. Significance was set at p < 0.05. After 12 weeks of intervention, there was a decrease in subcutaneous body fat (p < .0001), neck, abdomen and waist circumferences (p < .05), waist-to-hip ratio (p = .009), blood levels of interleukin (IL)-1β (p = .029), IL-6 (p = .005), IL-8 (p = .010), and tumour necrosis factor (TNF)-α (p = .001) and an increase in muscle strength (p < .0001), IL-10 levels (p = .030) and CD4(+) (p = .004) and CD8(+) (p < .0001) counts in the NLRT compared to CON group. Twelve weeks of NLRT promoted positive changes in the body fat, body circumferences, muscular strength and inflammatory profile in PIHIV.

Laryngeal Kaposi's Sarcoma Complicated by the Immune Reconstitution Inflammatory Syndrome in an HIV-infected Patient

We herein report a case of laryngeal Kaposi's sarcoma (KS) complicated by immune reconstitution inflammatory syndrome in a human immunodeficiency virus (HIV)-infected patient. The patient initially presented with KS involving the larynx, which was successfully treated with pegylated liposomal doxorubicin (PLD) and antiretroviral therapy (ART). PLD was discontinued after 2 courses because of a marked clinical improvement; however, the patient experienced progressive odynophagia and dyspnea 2 months after the initiation of ART. Laryngoscopy revealed a severely swollen, inflamed epiglottis. The readministration of PLD was successful, and the patient was thereafter discharged without any subsequent complications.

Therapeutics targeting inflammation in the immune reconstitution inflammatory syndrome

Immune reconstitution inflammatory syndrome (IRIS) is characterized by improvement in a previously incompetent human immune system manifesting as worsening of clinical symptoms secondary to the ability of the immune system to now mount a vigorous inflammatory response. IRIS was first recognized in the setting of human immunodeficiency virus, and this clinical setting continues to be where it is most frequently encountered. Hallmarks of the pathogenesis of IRIS, independent of the clinical presentation and the underlying pathogen, include excessive activation of the immune system, with increased circulating effector memory T cells, and elevated levels of serum cytokines and inflammatory markers. Patients with undiagnosed opportunistic infections remain at risk for unmasking IRIS at the time of active antiretroviral therapy (ART) initiation. Systematic screening for opportunistic infections before starting ART is a key element to prevent this phenomenon. Appropriate management of IRIS requires prompt recognition of the syndrome and exclusion of alternative diagnoses, particularly underlying infections and drug resistance. Controlled studies supporting the use of pharmacologic interventions in IRIS are scare, and recommendations are based on case series and expert opinions. The only controlled trial published to date, showed reduction in morbidity in patients with paradoxical tuberculosis-related IRIS with the use of oral corticosteroids. There are currently limited data to recommend other anti-inflammatory or immunomodulatory therapies that are discussed in this review, and further research is needed. Ongoing research regarding the immune pathogenesis of IRIS will likely direct future rational therapeutic approaches and clinical trials.

Understanding and intervening in HIV-associated tuberculosis

HIV-associated tuberculosis can present as extremes, ranging from acute life-threatening disseminated disease to occult asymptomatic infection. Both ends of this spectrum have distinct pathological correlates and require specific diagnostic and treatment approaches. Novel therapeutics, targeting both pathogen and host, are needed to augment pathogen clearance. In latent tuberculosis infection, enhancement of immune activation could be desirable. Antiretroviral therapy augments the beneficial effects of antitubercular therapy. However, in the context of high bacillary burden, antiretroviral therapy can also result in pathology (tuberculosis immune reconstitution inflammatory syndrome). In the immune reconstituting patient, modulation of immune activation controls tissue destruction. Interventions should also be appropriate and sustainable within the programmatic setting.

To have and have not: dissecting protective and pathologic immune recovery in TB-IRIS

Paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) is a growing concern for advanced HIV/TB coinfected patients in an era where antiretroviral therapy (ART) is started shortly after TB treatment initiation. This perspective discusses potential mechanisms underlying TB-IRIS, focusing on recent studies that implicate coordinated recovery in adaptive and innate immune responses following ART initiation in TB-IRIS. More broadly, HIV/TB patients are probably a heterogeneous group whose outcomes are determined by the direction in which these immune responses change following ART initiation. Finally, in addition to treatment interventions that are in the pipeline for TB-IRIS, we highlight the need for holistic management of HIV/TB coinfected patients, which go beyond the current definition of TB-IRIS and take into consideration long-term consequences of robust immune recovery on ART.

Lower Pre-Treatment T Cell Activation in Early- and Late-Onset Tuberculosis-Associated Immune Reconstitution Inflammatory Syndrome

Background

Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) is an inflammatory complication in HIV-TB co-infected patients receiving antiretroviral therapy (ART). The role of disturbed T cell reconstitution in TB-IRIS is not well understood. We investigated T cell activation and maturation profiles in patients who developed TB-IRIS at different intervals during ART.

Methods

Twenty-two HIV-TB patients who developed early-onset TB-IRIS and 10 who developed late-onset TB-IRIS were matched for age, sex and CD4 count to equal numbers of HIV-TB patients who did not develop TB-IRIS. Flow cytometry analysis was performed on fresh blood, drawn before and after ART initiation and during TB-IRIS events. T cell activation and maturation was measured on CD4+ and CD8+ T cells using CD45RO, CD38, HLA-DR, CCR7 and CD27 antibodies.

Results

CD8+ T cell activation before ART was decreased in both early-onset (77% vs. 82%, p = 0.014) and late-onset (71% vs. 83%, p = 0.012) TB-IRIS patients compared to non-IRIS controls. After ART initiation, the observed differences in T cell activation disappeared. During late-onset, but not early-onset TB-IRIS, we observed a skewing from memory to terminal effector CD4+ and CD8+ T cell populations (p≤0.028).

Conclusion

Our data provide evidence of reduced CD8+ T cell activation before ART as a common predisposing factor of early- and late-onset TB-IRIS. The occurrence of TB-IRIS itself was not marked by an over-activated CD8+ T cell compartment. Late- but not early-onset TB-IRIS was characterized by a more terminally differentiated T cell phenotype.

Optimal Timing of Antiretroviral Therapy Initiation for HIV-Infected Adults With Newly Diagnosed Pulmonary Tuberculosis: A Systematic Review and Meta-analysis

BACKGROUND

Initiation of antiretroviral therapy (ART) during tuberculosis (TB) treatment remains challenging.

PURPOSE

To assess evidence from randomized, controlled trials of the timing of ART initiation in HIV-infected adults with newly diagnosed pulmonary TB.

DATA SOURCES

PubMed, EMBASE, Cochrane Central Register of Controlled Trials, conference abstracts, and ClinicalTrials.gov (from January 1980 to May 2015).

STUDY SELECTION

Randomized, controlled trials evaluating early versus delayed ART initiation (1 to 4 weeks vs. 8 to 12 weeks after initiation of TB treatment) or deferred ART initiation (after the end of TB treatment).

DATA EXTRACTION

Three reviewers independently extracted data and assessed risk of bias. The main outcome measures were all-cause mortality and the TB-associated immune reconstitution inflammatory syndrome (TB-IRIS).

DATA SYNTHESIS

The 8 included trials (n = 4568) were conducted in Africa, Asia, and the United States and were generally at low risk of bias for the assessed domains. Overall, early ART reduced mortality compared with delayed ART (relative risk [RR], 0.81 [95% CI, 0.66 to 0.99]; I2 = 0%). In a prespecified subgroup analysis, early ART reduced mortality compared with delayed ART among patients with baseline CD4+ T-cell counts less than 0.050 × 109 cells/L (RR, 0.71 [CI, 0.54 to 0.93]; I2 = 0%). However, a mortality benefit from early ART was not found among those with CD4+ T-cell counts greater than 0.050 × 109 cells/L (RR, 1.05 [CI, 0.68 to 1.61]; I2 = 56%). Early ART was associated with a higher incidence of TB-IRIS than delayed ART (RR, 2.31 [CI, 1.87 to 2.86]; I2 = 19%).

LIMITATION

Few trials provided sufficient data for subgroup analysis.

CONCLUSION

Early ART in HIV-infected adults with newly diagnosed TB improves survival in those with CD4+ T-cell counts less than 0.050 × 109 cells/L, although this is associated with a 2-fold higher frequency of TB-IRIS. In patients with CD4+ T-cell counts greater than 0.050 × 109 cells/L, evidence is insufficient to support or refute a survival benefit conferred by early versus delayed ART initiation.

PRIMARY FUNDING SOURCE

None. (PROSPERO registration: CRD42012001884).

Human immunodeficiency virus and coinfection with hepatitis B and C

In HIV-infected individuals, coinfection with HBV and/or HCV is common because of shared modes of transmission. It is known that HIV accelerates progression of liver disease and results in increased morbidity and mortality associated with viral hepatitis, but it is less clear if viral hepatitis has a direct effect on HIV. Treatment of viral hepatitis improves outcomes and should be considered in all HIV-infected patients. Treatment of HBV without concurrent treatment of HIV is risky because resistance can occur in both viruses if regimens are not carefully chosen.

Opportunistic infections and immune reconstitution inflammatory syndrome in HIV-1-infected adults in the combined antiretroviral therapy era: a comprehensive review

Despite the availability of effective combined antiretroviral treatment, many patients still present with advanced HIV infection, often accompanied by an AIDS-defining disease. A subgroup of patients starting antiretroviral treatment under these clinical conditions may experience paradoxical worsening of their disease as a result of an exaggerated immune response towards an active (but also subclinical) infectious agent, despite an appropriate virological and immunological response to the treatment. This clinical condition, known as immune reconstitution inflammatory syndrome, may cause significant morbidity and even mortality if it is not promptly recognized and treated. This review updates current knowledge about the incidence, diagnostic criteria, risk factors, clinical manifestations, and management of opportunistic infections and immune reconstitution inflammatory syndrome in the combined antiretroviral treatment era.

Inflammation and tuberculosis: host-directed therapies

Tuberculosis (TB) is an airborne infectious disease that kills almost two million individuals every year. Multidrug-resistant (MDR) TB is caused by strains of Mycobacterium tuberculosis (M. tb) resistant to isoniazid and rifampin, the backbone of first-line antitubercular treatment. MDR TB affects an estimated 500,000 new patients annually. Genetic analysis of drug-resistant MDR-TB showed that airborne transmission of undetected and untreated strains played a major role in disease outbreaks. The need for new TB vaccines and faster diagnostics, as well as the development of new drugs, has recently been highlighted. The major problem in terms of current TB research and clinical demands is the increasing number of cases of extensively drug-resistant and 'treatment-refractory' TB. An emerging scenario of adjunct host-directed therapies is intended to target pulmonary TB where inflammatory processes can be deleterious and lead to immune exhaustion. 'Target-organ-saving' strategies may be warranted to prevent damage to infected tissues and achieve focused, clinically relevant and long-lasting anti-M. tb cellular immune responses. Candidates for such interventions may be biological agents or already approved drugs that can be 're-purposed' to interfere with biologically relevant cellular checkpoints. Here, we review current concepts of inflammation in TB disease and discuss candidate pathways for host-directed therapies to achieve better clinical outcomes.

Immune reconstitution inflammatory syndrome in HIV-infected patients

Access to antiretroviral therapy (ART) is improving worldwide. Immune reconstitution inflammatory syndrome (IRIS) is a common complication of ART initiation. In this review, we provide an overview of clinical and epidemiological features of HIV-associated IRIS, current understanding of pathophysiological mechanisms, available therapy, and preventive strategies. The spectrum of HIV-associated IRIS is described, with a particular focus on three important pathogen-associated forms: tuberculosis-associated IRIS, cryptococcal IRIS, and Kaposi's sarcoma IRIS. While the clinical features and epidemiology are well described, there are major gaps in our understanding of pathophysiology and as a result therapeutic and preventative strategies are suboptimal. Timing of ART initiation is critical to reduce IRIS-associated morbidity. Improved understanding of the pathophysiology of IRIS will hopefully enable improved diagnostic modalities and better targeted treatments to be developed.

Effect of the CCR5 antagonist maraviroc on the occurrence of immune reconstitution inflammatory syndrome in HIV (CADIRIS): a double-blind, randomised, placebo-controlled trial

BACKGROUND

Immune reconstitution inflammatory syndrome (IRIS) is a common complication of antiretroviral therapy (ART) in patients with HIV. IRIS is associated with an increased risk of admission to hospital and death. We assessed whether CCR5 blockade with maraviroc reduces the risk of IRIS.

METHODS

The CADIRIS study was a double-blind, randomised, placebo-controlled trial that recruited participants from five clinical sites in Mexico and one in South Africa and followed them for 1 year. Patients were eligible if they were adults with HIV, who were naive to ART, had CD4 count lower than 100 cells per μL and HIV RNA greater than 1000 copies per mL. Participants were randomly assigned (1:1) by permuted block randomisation to receive either maraviroc (600 mg twice daily) or placebo in addition to an ART regimen that included tenofovir, emtricitabine, and efavirenz for 48 weeks. Patients, care providers, and members of the research team were masked to treatment allocation. Clinical and laboratory evaluations were done at baseline, and weeks 2, 4, 8, 12, 16, 24, 48, and 60. The primary outcome was time to an IRIS event by 24 weeks. All patients who were randomly assigned contributed to the primary time-to-event analysis from the date of ART initiation until week 24, the time of an IRIS event or death. This trial is registered with ClinicalTrials.gov, number NCT00988780.

FINDINGS

Between Dec 10, 2009, and Jan 17, 2012, we screened 362 patients; of whom 279 met the inclusion criteria and three refused to participate; thus 276 participants were randomly assigned (140 to receive maraviroc and 136 to receive placebo). 64 (23%) patients had IRIS events, 33 (24%) in the maraviroc group and 31 (23%) in the placebo group (p=0·74). No difference in the time to IRIS events was noted between the treatment groups (HR 1·08, 95% CI 0·66-1·77; log-rank test p=0·74). 37 participants (26%) in the maraviroc group had grade 3 or 4 adverse events compared with 24 (18%) in placebo group; p=0·072); 25 (18%) in the maraviroc group and 21 (15%) in the placebo group had serious treatment emergent adverse events (p=0·63).

INTERPRETATION

Maraviroc had no significant effect on development of IRIS after ART initiation. Inclusion of this CCR5 inhibitor in an initial treatment regimen does not confer a meaningful protection from the occurrence of IRIS in people with advanced HIV infection.

FUNDING

Pfizer.

A rare case of immune reconstitution inflammatory syndrome presenting as secondary syphilis

Immune reconstitution syndrome has rarely been reported in the context of syphilis infection. We report a patient with AIDS (CD4 42 cells/mm(3), viral load 344,000 cp/ml), treated previously for secondary syphilis and started on an integrase inhibitor-based single-tablet antiretroviral treatment regimen. After four weeks of antiretroviral treatment, he presented with non-tender, non-blanching erythematous nodules on his chest, an elevated rapid plasma reagin (1:1024) and immune reconstitution (CD4 154 cells/mm(3), HIV-RNA 130 cp/ml). A detailed workup to exclude opportunistic infections including secondary and neurosyphilis was performed. The patient was continued on antiretroviral treatment and treated empirically for neurosyphilis given cerebrospinal lymphocytosis and dermatopathology suggesting treponemal antigen-driven B-cell hyperplasia. We favour a diagnosis of immune reconstitution in association with prior syphilis infection attributable to rapid and potent immune restoration afforded by integrase inhibitors.

Mycobacterial antigen driven activation of CD14++CD16- monocytes is a predictor of tuberculosis-associated immune reconstitution inflammatory syndrome

Paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) is an aberrant inflammatory response occurring in a subset of TB-HIV co-infected patients initiating anti-retroviral therapy (ART). Here, we examined monocyte activation by prospectively quantitating pro-inflammatory plasma markers and monocyte subsets in TB-HIV co-infected patients from a South Indian cohort at baseline and following ART initiation at the time of IRIS, or at equivalent time points in non-IRIS controls. Pro-inflammatory biomarkers of innate and myeloid cell activation were increased in plasma of IRIS patients pre-ART and at the time of IRIS; this association was confirmed in a second cohort in South Africa. Increased expression of these markers correlated with elevated antigen load as measured by higher sputum culture grade and shorter duration of anti-TB therapy. Phenotypic analysis revealed the frequency of CD14⁺⁺CD16⁻ monocytes was an independent predictor of TB-IRIS, and was closely associated with plasma levels of CRP, TNF, IL-6 and tissue factor during IRIS. In addition, production of inflammatory cytokines by monocytes was higher in IRIS patients compared to controls pre-ART. These data point to a major role of mycobacterial antigen load and myeloid cell hyperactivation in the pathogenesis of TB-IRIS, and implicate monocytes and monocyte-derived cytokines as potential targets for TB-IRIS prevention or treatment.

Tuberculosis and HIV majorly impact host immune responses, resulting in immune deregulation and inflammation-driven tissue damage. Initiation of anti-retroviral therapy in patients with HIV-TB co-infection may result in immune reconstitution inflammatory syndrome (TB-IRIS), a disorder associated with increased immunopathology due to unfettered inflammation after CD4⁺ T-cell reconstitution. Monocytes are critical to the innate immune system and play an important role in several inflammatory conditions associated with chronic infections. Immunopathogenesis of TB-IRIS has been linked to activation of the adaptive immune response against opportunistic infection, yet the role of monocytes is still unknown. Here we investigated associations between soluble markers of monocyte activation, differential activation of monocyte subsets and TB-IRIS prospectively in two geographically distinct HIV-TB co-infected patient cohorts. Prior to ART initiation, patients who developed IRIS displayed a biosignature of elevated soluble monocyte activation markers, which were closely related to the mycobacterial antigen load in sputum samples. Amongst monocyte subsets, we observed that pre-ART circulating CD14⁺⁺CD16⁻ cell frequency independently predicted TB-IRIS and expanded during IRIS events. This monocyte subset was tightly associated with systemic markers of inflammation, and was found to produce inflammatory cytokines. Identification of this monocyte subset and its link with inflammation may lead to conception of novel therapies reducing immunopathology in TB-IRIS.

Prognostic evaluation of DNA index in HIV-HPV co-infected women cervical samples attending in reference centers for HIV-AIDS in Recife

INTRODUCTION

Persistence of cervical infection caused by human papillomavirus (HPV) types with high oncogenic risk may lead to cervical intraepithelial neoplasia (CIN). The aim of the present study was to evaluate whether, in HIV-positive women, the presence of aneuploidy in cervical cell samples is associated with presence and evolution of CIN.

METHODS

The present study had two stages. In the first stage, comprising a cross-sectional study, the association between the presence of aneuploidy seen via flow cytometry and sociodemographic characteristics, habits and characteristics relating to HPV and HIV infection was analyzed. In the second stage, comprising a cohort study, it was investigated whether aneuploidy was predictive of CIN evolution.

RESULTS

No association was observed between the presence of aneuploidy and HPV infection, or between its presence and alterations seen in oncotic cytological analysis. On the other hand, aneuploidy was associated with the presence of CIN (p = 0.030) in histological analysis and with nonuse of antiretroviral therapy (p = 0.001). Most of the HIV-positive women (234/272) presented normal CD4+ T lymphocyte counts (greater than 350 cells/mm3) and showed a greater aneuploidy regression rate (77.5%) than a progression rate (23.9%) over a follow-up of up to two years.

CONCLUSION

Although there was an association between the presence of cervical tissue lesions and the DNA index, the latter was not predictive of progression of the cervical lesion. This suggests that progression of the cervical lesion to cancer in HIV-positive women may also be changed through improvement of the immunological state enabled by using antiretroviral therapy.

HIV infection: epidemiology, pathogenesis, treatment, and prevention

HIV prevalence is increasing worldwide because people on antiretroviral therapy are living longer, although new infections decreased from 3.3 million in 2002, to 2.3 million in 2012. Global AIDS-related deaths peaked at 2.3 million in 2005, and decreased to 1.6 million by 2012. An estimated 9.7 million people in low-income and middle-income countries had started antiretroviral therapy by 2012. New insights into the mechanisms of latent infection and the importance of reservoirs of infection might eventually lead to a cure. The role of immune activation in the pathogenesis of non-AIDS clinical events (major causes of morbidity and mortality in people on antiretroviral therapy) is receiving increased recognition. Breakthroughs in the prevention of HIV important to public health include male medical circumcision, antiretrovirals to prevent mother-to-child transmission, antiretroviral therapy in people with HIV to prevent transmission, and antiretrovirals for pre-exposure prophylaxis. Research into other prevention interventions, notably vaccines and vaginal microbicides, is in progress.

Changes in biomarkers in HIV-1-infected treatment-naive patients treated with tenofovir DF/emtricitabine plus atazanavir/ritonavir or lopinavir/ritonavir for 96 weeks: the CASTLE biomarker substudy

BACKGROUND

The impact of boosted protease inhibitor therapy on inflammatory and cardiovascular biomarker levels in treatment-naive HIV-infected patients remains unclear and may differ between agents. Unconjugated bilirubin elevation, which favourably affects vascular biomarkers and cardiovascular disease risk in Gilbert's syndrome, occurs with atazanavir.

METHODS

CASTLE was a 96-week study comparing efficacy and safety in treatment-naive HIV-1-infected patients randomized to atazanavir/ritonavir (ATV/r) versus lopinavir/ritonavir (LPV/r), each in combination with tenofovir disoproxil fumarate/emtricitabine. In this substudy, fasting plasma tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), high sensitivity C-reactive protein (hs-CRP), plasminogen activator inhibitor-1 (PAI-1) and fibrinogen were assessed at baseline, week 12, 24, 48 and 96. Impact of grade 3-4 hyperbilirubinaemia on biomarkers was examined.

RESULTS

CASTLE demonstrated similar efficacy in both treatment arms with higher rates of hyperbilirubinaemia on ATV/r and elevated lipids on LPV/r. In this substudy (n=224), patterns of biomarker expression were similar between the ATV/r and LPV/r groups and between-group differences in biomarker percentage change from baseline were not significant at 48 and/or 96 weeks. Hyperbilirubinaemia did not influence fasting biomarker expression.

CONCLUSIONS

No significant differences were noted between ATV/r and LPV/r for biomarker percentage changes from baseline. Furthermore, no association was found between total bilirubin levels and biomarker expression.

Tuberculosis-immune reconstitution inflammatory syndrome in HIV: from pathogenesis to prediction

Tuberculosis-immune reconstitution inflammatory syndrome (TB-IRIS) is an exaggerated, dysregulated immune response against dead or viable antigens of Mycobacterium tuberculosis that frequently occurs after initiation of antiretroviral therapy despite an effective suppression of HIV viremia. Scientific advances in IRIS pathogenesis have led researchers and clinicians to postulate risk factors that could possibly predict this syndrome, in an attempt to reduce the incidence and the severity of IRIS, with appropriate anti-inflammatory therapy. This review is a summary of the available literature on pathogenic mechanisms involved from the macro to the micro level, the clinical spectrum, available predictors and the scope of these biomarkers to function as specific therapeutic targets, that could effectively modulate or ameliorate this syndrome in future.

Management of HIV-associated tuberculosis in resource-limited settings: a state-of-the-art review

The HIV-associated tuberculosis (TB) epidemic remains a huge challenge to public health in resource-limited settings. Reducing the nearly 0.5 million deaths that result each year has been identified as a key priority. Major progress has been made over the past 10 years in defining appropriate strategies and policy guidelines for early diagnosis and effective case management. Ascertainment of cases has been improved through a twofold strategy of provider-initiated HIV testing and counseling in TB patients and intensified TB case finding among those living with HIV. Outcomes of rifampicin-based TB treatment are greatly enhanced by concurrent co-trimoxazole prophylaxis and antiretroviral therapy (ART). ART reduces mortality across a spectrum of CD4 counts and randomized controlled trials have defined the optimum time to start ART. Good outcomes can be achieved when combining TB treatment with first-line ART, but use with second-line ART remains challenging due to pharmacokinetic drug interactions and cotoxicity. We review the frequency and spectrum of adverse drug reactions and immune reconstitution inflammatory syndrome (IRIS) resulting from combined treatment, and highlight the challenges of managing HIV-associated drug-resistant TB.

Incidence, clinical spectrum, diagnostic features, treatment and predictors of paradoxical reactions during antibiotic treatment of Mycobacterium ulcerans infections

Background

Paradoxical reactions from antibiotic treatment of Mycobacterium ulcerans have recently been recognized. Data is lacking regarding their incidence, clinical and diagnostic features, treatment, outcomes and risk factors in an Australian population.

Methods

Data was collected prospectively on all confirmed cases of M. ulcerans infection managed at Barwon Health Services, Australia, from 1/1/1998-31/12/2011. Paradoxical reactions were defined on clinical and histological criteria and cases were determined by retrospectively reviewing the clinical history and histology of excised lesions. A Poisson regression model was used to examine associations with paradoxical reactions.

Results

Thirty-two of 156 (21%) patients developed paradoxical reactions a median 39 days (IQR 20-73 days) from antibiotic initiation. Forty-two paradoxical episodes occurred with 26 (81%) patients experiencing one and 6 (19%) multiple episodes. Thirty-two (76%) episodes occurred during antibiotic treatment and 10 (24%) episodes occurred a median 37 days after antibiotic treatment. The reaction site involved the original lesion (wound) in 23 (55%), was separate to but within 3 cm of the original lesion (local) in 11 (26%) and was more than 3 cm from the original lesion (distant) in 8 (19%) episodes. Mycobacterial cultures were negative in 33/33 (100%) paradoxical episodes. Post-February 2009 treatment involved more cases with no antibiotic modifications (12/15 compared with 11/27, OR 5.82, 95% CI 1.12-34.07, p = 0.02) and no further surgery (9/15 compared with 2/27, OR 18.75, 95% CI 2.62-172.73, p < 0.001). Six severe cases received prednisone with marked clinical improvement. On multivariable analysis, age ≥ 60 years (RR 2.84, 95% CI 1.12-7.17, p = 0.03), an oedematous lesion (RR 3.44, 95% CI 1.11-10.70, p=0.03) and use of amikacin in the initial antibiotic regimen (RR 6.33, 95% CI 2.09-19.18, p < 0.01) were associated with an increased incidence of paradoxical reactions.

Conclusions

Paradoxical reactions occur frequently during or after antibiotic treatment of M. ulcerans infections in an Australian population and may be increased in older adults, oedematous disease forms, and in those treated with amikacin. Recognition of paradoxical reactions led to changes in management with less surgery, fewer antibiotic modifications and use of prednisolone for severe reactions.

Update on progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a severe, often fatal, opportunistic viral infection of the central nervous system that is mainly seen in the context of AIDS and certain monoclonal immune-suppressive therapies. The causative agent, a polyoma virus, named JC virus infects only humans and there is no animal model for PML. This update focuses on information gathered in recent years on the pathogenesis of the disorder, on several clinical aspects associated with diagnosis and therapy, and on the immune reconstitution inflammatory syndrome (IRIS), a complication associated with removal of immunosuppressive therapy in PML.

Critical care of persons infected with the human immunodeficiency virus

Antiretroviral therapy (ART) has transformed the prognosis for patients infected with the human immunodeficiency virus (HIV). With effective ART, these individuals can expect to live almost as long as their HIV-negative counterparts. Given that more than a million people infected with HIV currently live in the United States, the likelihood that the practicing intensivist will manage a patient infected with HIV is high. This review discusses the challenges associated with management of critically ill patients infected with HIV, including the immune reconstitution inflammatory syndrome (a complication associated with ART initiation), ART-related toxicities, and the management of some common opportunistic infections.

The immune reconstitution inflammatory syndrome: a clinical update

The immune reconstitution inflammatory syndrome (IRIS) is a well-described phenomenon in HIV-infected patients following initiation of antiretroviral therapy and can lead to significant morbidity and mortality in some patients. Risk for IRIS is enhanced in those with low CD4 counts and preexisting opportunistic infections. The development of pathogen-specific definitions of IRIS has aided classification of patients and has facilitated research. Newer data on optimal timing of ART initiation, with additional data in the setting of tuberculosis and cryptococcal meningitis, will help guide strategies to decrease the risk of IRIS but must balance the risks of HIV disease progression. Managing patients with IRIS can be challenging. Treatment options include pathogen-specific therapy, antiinflammatory therapies, and other novel approaches.