The immunocompromised host: HIV infection

COVID-19 infection in a HIV positive health care worker: first case report from a tertiary care hospital of North India

People living with Human Immunodeficiency Virus (PLHIV) are at greater risk of developing prolonged illness due to COVID 19 leading to longer duration of virus shedding owing to their underlying immune defects. The present study compared SARS-CoV-2 infection developing at the same time among two health care workers living with and without a history of HIV and working in the same ward of a tertiary care hospital of North India. A higher viral load was reported in the SARS-CoV-2 infected worker who was immunocompromised as compared to immunocompetent patient (19,193 copies/µL vs 9.4 copies/µL). In this preliminary case report, no difference was observed in the clinical presentation of both patients at the time of diagnosis. Further studies are required to investigate the COVID-19 susceptibility and severity among HIV-infected patients.

Adverse events after vaccination among HIV-positive persons, 1990-2016

Human immunodeficiency virus (HIV) causes immune dysregulation, potentially affecting response to vaccines in infected persons. We investigated if unexpected adverse events (AEs) or unusual patterns of AEs after vaccination were reported among HIV-positive persons. We searched for domestic reports among HIV-positive persons to the Vaccine Adverse Event Reporting System (VAERS) during 1990–2016. We analyzed reports by age group (<19 and ≥19 years), sex, serious or non-serious status, live vaccine type (live versus inactivated), AEs reported, and CD4 counts. Of 532,235 reports received, 353 (0.07%) described HIV-positive persons, of whom 67% were aged ≥19 years, and 57% were male; most reports (75%) were non-serious. The most commonly reported inactivated vaccines were pneumococcal polysaccharide (27%) and inactivated influenza (27%); the mostly reported common live virus vaccines were combination measles, mumps, and rubella (8%) and varicella (6%). Injection site reactions were commonly reported (39%). Of 67 reports with CD4 counts available, 41 (61%) described persons immunocompromised at time of vaccination (CD4 count <500 cells/mm³), and differed from overall reports only in that varicella was the most common live virus vaccine (4 reports). Of 22 reports describing failure to protect against infection, 6 described persons immunocompromised at time of vaccination, among whom varicella vaccine was most common (3 reports). Of 66 reports describing live virus vaccines, 7 described persons with disseminated infection: 6 had disseminated varicella, 3 of whom had vaccine strain varicella-zoster virus. Of 18 reported deaths, 7 resulted from disseminated infection: 6 were among immunocompromised persons, 1 of whom had vaccine strain varicella-zoster virus. We identified no unexpected or unusual patterns of AEs among HIV-positive persons. These data reinforce current vaccine recommendations for this risk group. However, healthcare providers should know their HIV-positive patients’ immune status because immunocompromising conditions can potentially increase the risk of rare, but severe, AEs following vaccination with live virus vaccines.

The role of SAMHD1 expression and its relation to HIV-2 (Vpx) gene production

SAMHD1 (sterile alpha motif and HD domain 1) is a protein that is found in myeloid cells, which restricts HIV1 replication. It depletes the de-oxy-nucleoside tri-phosphate (dNTPs) pool needed for a viral cDNA synthesis leading to inhibition of viral replication inside the cells. However, it does not restrict HIV2 replication in myeloid cells due to the presence of viral Vpx protein. Vpx is a virion-associated protein which augments viral infectivity and it only exists in HIV2 and it has been recently shown in Simian Immunodeficiency Virus (SIV) and which can induce degradation of SAMHD1 protein. This increases the amount of dNTPs for viral reverse transcription in cytoplasm and HIV infection. HIV2 reverse transcription is believed to be less active than HIV1 and this could be the reason for the absence of Vpx from HIV1. Protein expression and interaction between Vpx and SAMHD1 remains unclear. The interaction of SAMHD1 and HIV2-VPx patients' cells can be considered as a first step to help in the development for more effective anti-HIV drugs and possible novel intervention therapy in the future. Present review article provides comprehensive insights on the above issue. We performed a comprehensive literature search in the bibliographic database “Pubmed,” looking at studies discussing the SAMHDI and Vpx interactions.

Correlation of CD4 counts with clinical and histopathological findings in disseminated histoplasmosis: a 10-year retrospective study

BACKGROUND

Disseminated cutaneous histoplasmosis (DCH) is one of the manifestations of systemic histoplasmosis infection in HIV-positive patients. Interaction between host immune status and histoplasmosis infection is still poorly understood. It is thought that immune status, represented by CD4 counts, may be correlated with clinical and histopathological findings.

OBJECTIVE

To correlate the CD4 counts with the different clinical and histopathological findings in cutaneous histoplasmosis.

METHODS

This was a serial case report of seven HAART-treated HIV positive patients with disseminated histoplasmosis observed within the period of January 2004 through December 2014 from the Dermatology and Venereology Department, Cipto Mangunkusumo Hospital, Jakarta, Indonesia. The patients came with different complaints and clinical findings. CD4 counts were recorded prior to lesion biopsy.

RESULTS

The CD4 counts were independent from clinical morphology and distribution of lesions. Lower CD4 counts were associated with the presence of intraepidermal yeast-like cells, whereas there is the ability of forming granulomas at higher CD4 counts.

CONCLUSION

CD4 count correlates to histopathological findings of cutaneous histoplasmosis.

Lower Respiratory Tract Infections

This review will focus on the infectious etiologies and more common noninfectious causes of lower respiratory tract syndromes among major immunosuppressed populations. The changing epidemiology of infections in the era of highly active antiretroviral therapy (HAART) in the case of HIV-positive patients and the impacts of both newer immune-suppressant therapies and anti-infective prophylaxis for other immunocompromised hosts will be discussed, with emphasis on diagnostic approaches and practice algorithms.

B cells as multi-functional players during Mycobacterium tuberculosis infection and disease

Immunity to tuberculosis is still understood to be driven and maintained by T-cell derived immune responses. With a steady influx of data, it is becoming clear that B cells, the mediators of humoral immunity, have the capacity to function in roles not previously appreciated within the traditional B cell dogma. In this review we aim to discuss B cells, from its generation through to its functioning as effectors in both the innate and adaptive immune response, within the tuberculosis domain.

Abnormalities in host defense associated with HIV infection

The broad variety of pulmonary infections encountered in human immunodeficiency virus (HIV)-infected individuals demonstrates that the host defense network is impaired. An improved understanding of these events in the lung can lead to specific interventions aimed at restoration of deficient function. This review summarizes the pulmonary host defense deficits in HIV-infected individuals, focusing on lymphocytes, alveolar macrophages, and neutrophils.

HIV-1 and bacterial pneumonia in the era of antiretroviral therapy

Community-acquired pneumonia affects approximately 4 million people in the United States, with 40,000 deaths per year. The incidence is increased about 35-fold in HIV-infected individuals, and this rate has decreased since the antiretroviral era has begun. Bacterial pneumonia has decreased from 5 to 20 cases per 100 person-years to less than 1 to 5 cases per 100 person-years in the era of antiretroviral therapy. HIV-1 infection impairs the function of neutrophils in the lung and infects CD4⁺ cells and alveolar macrophages. Opportunistic infections dramatically increase local HIV replication in the lung cells, especially alveolar macrophages and CD4⁺ cells. This enhanced replication increases viral mutations and provides opportunities for viral escape from latent reservoirs. Mortality is increased with more comorbidities in this highly susceptible population. Immunization with vaccines is recommended, especially pneumococcal vaccines, although the vaccine itself may stimulate viral replication. Recent studies show that the lower respiratory tract is a microbial reservoir in HIV-infected individuals rather than being a sterile environment, as originally thought. This may provide new opportunities for preventing opportunistic infections in HIV-infected subjects. Bacterial pneumonia presents an ongoing challenge in these high-risk individuals, particularly in studying the functions of the innate and acquired immune response.

HIV-associated lung infections and complications in the era of combination antiretroviral therapy

The spectrum of lung diseases associated with HIV is broad, and many infectious and noninfectious complications of HIV infection have been recognized. The nature and prevalence of lung complications have not been fully characterized since the Pulmonary Complications of HIV Infection Study more than 15 years ago, before antiretroviral therapy (ART) increased life expectancy. Our understanding of the global epidemiology of these diseases in the current ART era is limited, and the mechanisms for the increases in the noninfectious conditions, in particular, are not well understood. The Longitudinal Studies of HIV-Associated Lung Infections and Complications (Lung HIV) Study (ClinicalTrials.gov number NCT00933595) is a collaborative multi-R01 consortium of research projects established by the National Heart, Lung, and Blood Institute to examine a diverse range of infectious and noninfectious pulmonary diseases in HIV-infected persons. This article reviews our current state of knowledge of the impact of HIV on lung health and the development of pulmonary diseases, and highlights ongoing research within the Lung HIV Study.

An official ATS workshop report: Emerging issues and current controversies in HIV-associated pulmonary diseases

Pulmonary diseases are major causes of morbidity and death in persons with HIV infection. Millions of people with HIV/AIDS throughout the world are at risk of opportunistic pneumonias such as tuberculosis, bacterial pneumonia, and Pneumocystis pneumonia. However, the availability of combination antiretroviral therapy has turned HIV into a chronic disease, and noninfectious lung diseases such as lung cancer, chronic obstructive pulmonary disease, and pulmonary arterial hypertension are also emerging as important causes of illness. Despite the importance of these diseases and the rapidly evolving understanding of their pathogenesis and epidemiology, few avenues exist for the discussion and dissemination of new clinical and basic insights. In May of 2008, the American Thoracic Society sponsored a 1-day workshop, "Emerging Issues and Current Controversies in HIV-Associated Pulmonary Diseases," which brought together basic and clinical researchers in HIV-associated pulmonary disease. A review of the literature was performed by workshop participants, and the workshop included 18 presentations on diverse topics summarized in this article.

Epstein-Barr virus (EBV) gene expression in interstitial pneumonitis in Brazilian human immunodeficiency virus-1-infected children: is EBV associated or not?

To gain further knowledge on the subject we evaluated Epstein-Barr virus (EBV) gene expression and TCD4+, TCD8+, and B lymphocyte counts in lung tissue samples from 20 human immunodeficiency virus (HIV)-infected children with chronic lung disease. Twenty HIV-1 infected children with chronic pulmonary disease underwent open lung biopsy to define the diagnosis. Histological section of this material was submitted to nonisotopic in situ hybridization (ISH) using EBV-encoded RNA (EBER) 1/2 probes and TCD4+, TCD8+, and CD20+ B-cell counts by immunohistochemistry. The histology of 16 out of the 20 children (median age 53.5 months) proved to be examples of pulmonary lymphoid hyperplasia/lymphoid interstitial pneumonitis (PLH/LIP) complex, 13 of which were EBER positive, but no significant association was found (Fisher exact test P = 0.439). Four patients had non-LIP diseases (3, nonspecific interstitial pneumonia; 1, diffuse advanced alveolar damage), two being EBER negative. Nineteen children showed a predominant T-CD8+ cell response (CD4+/CD8+ <1) in lung tissue. The mean TCD4+ and theTCD4/TCD8 ratio in lung tissue were significantly higher in the sections with PLH/LIP complex, but without significant difference between EBER positive and EBER negative samples. EBV gene expression was detected in the majority of the lung samples but without significant association with PLH/LIP complex or with TCD4+, TCD8+, B cells and the TCD4+/TCD8+ ratio. Regarding the pattern of lung disease in HIV-1 infected children, associated or not to EBV, the findings are of importance concerning the possible role of EBV in the pathogenesis of PLH/LIP.

Vaccination in adults with auto-immune disease and/or drug related immune deficiency: results of the GEVACCIM Delphi survey

INTRODUCTION

There are insufficient data regarding the efficacy and safety of vaccination in patients with auto-immune disease (AID) and/or drug-related immune deficiency (DRID). The objective of this study was to obtain professional agreement on vaccine practices in these patients.

METHODS

A Delphi survey was carried out with physicians recognised for their expertise in vaccinology and/or the caring for adult patients with AID and/or DRID. For each proposed vaccination practice, the experts' opinion and level of agreement were evaluated.

RESULTS

The proposals relating to patients with AID specified: the absence of risk of AID relapse following vaccination; the possibility of administering live virus vaccines (LVV) to patients not receiving immunosuppressants; the pertinence of determining protective antibody titre before vaccination; the absence of need for specific monitoring following the vaccination. The proposals relating to patients with DRID specified that a 3-6 month delay is needed between the end of these treatments and the vaccination with LVV. There is no contraindication to administering LVV in patients receiving systemic corticosteroids prescribed for less than two weeks, regardless of their dose, or at a daily dose not exceeding 10mg of prednisone, if this involves prolonged treatment. Out of 14 proposals, the level of agreement between the experts was "very good" for eleven, and "good" for the remaining three.

CONCLUSION

Proposals for vaccine practices in patients with AID and/or DRID should aid with decision-making in daily medical practice and provide better vaccine coverage for these patients.

Changing global epidemiology of pulmonary manifestations of HIV/AIDS

Tremendous advances have occurred in the care of patients with HIV/AIDS resulting from the advent of highly active antiretroviral therapy (HAART). This has led to differences in the presentations of HIV-related pulmonary disease. Infections such as bacterial pneumonias, particularly Streptococcus pneumoniae, remain commonplace, while opportunistic agents such as Pneumocystis jirovecii remain a concern in patients without adequate access to optimal medical care. The tuberculosis epidemic, once thought to be slowing, has been re-energized by the spread of HIV, particularly in sub-Saharan Africa. Unusual inflammatory responses due to a phenomenon of immune reconstitution, are now recognized as a consequence of HAART, with a reported incidence of IRIS in this setting ranges from 7 to 45% in retrospective reviews. Noninfectious pulmonary conditions such as chronic obstructive lung disease and pulmonary malignancies are gaining prominence as patients are accessing antiretroviral care and enjoying significantly extended survival.

Comparison of the effects of pathogenic simian human immunodeficiency virus strains SHIV-89.6P and SHIV-KU2 in cynomolgus macaques

Factors explaining why human immunodeficiency virus (HIV) enhances the risk of reactivated tuberculosis (TB) are poorly understood. Unfortunately, experimental models of HIV-induced reactivated TB are lacking. We examined whether cynomolgus macaques, which accurately model latent TB in humans, could be used to model pathogenesis of HIV infection in the lungs and associated lymph nodes. These experiments precede studies modeling the effects of HIV infection on latent TB. We infected two groups of macaques with chimeric simian-human immunodeficiency viruses (SHIV-89.6P and SHIV-KU2) and followed viral titers and immunologic parameters including lymphocytes numbers and phenotype in the blood, bronchoalveolar lavage cells, and lymph nodes over the course of infection. Tissues from the lungs, liver, kidney, spleen, and lymph nodes were similarly examined at necropsy. Both strains produced dramatic CD4(+) T cell depletion. Plasma titers were not different between viruses, but we found more SHIV-89.6P in the lungs. Both viruses induced similar patterns of cell activation markers. SHIV-89.6P induced more IFN-gamma expression than SHIV-KU2. These results indicate SHIV-89.6P and SHIV-KU2 infect cynomolgus macaques and may be used to accurately model effects of HIV infection on latent TB.

Overexpression of Suppressor of Cytokine Signaling-5 in T Cells Augments Innate Immunity during Septic Peritonitis

Suppressors of cytokine signaling (SOCS) proteins are negative regulators of cytokine signaling by inhibiting the JAK-STAT signal transduction pathway, but their role in innate immunity remains to be investigated. In the present study, we demonstrate that overexpression of SOCS5 in T cells augments innate immunity during septic peritonitis induced by cecal ligation and puncture (CLP). Mice with a cell-specific overexpression of SOCS5 in T cells (SOCS5 transgenic (Tg)) were resistant to the lethality relative to the wild-type (WT) mice. This was most likely due to the enhanced innate immunity in SOCS5Tg mice, as bacterial burden in SOCS5Tg mice was significantly lower than WT mice. Accumulation of neutrophils and macrophages was augmented in SOCS5Tg mice, an event that was accompanied by increased peritoneal levels of IL-12, IFN-gamma, and TNF-alpha. In vitro bactericidal activities of macrophages and neutrophils were enhanced in SOCS5Tg mice. Both neutrophils and macrophages from WT mice adopted enhanced bacterial killing activity when cocultured with CD4+ T cells from SOCS5Tg mice, relative to CD4+ T cells from WT mice. Adoptive transfer of SOCS5Tg-CD4+ T cells into T- and B cell-deficient RAG-2(-/-) mice resulted in augmented leukocyte infiltration and increased peritoneal levels of IL-12, IFN-gamma, and TNF-alpha after CLP, as compared with the controls. Furthermore, CLP-induced bacterial burden in RAG-2(-/-) mice harboring SOCS5Tg-CD4+ T cells was significantly reduced relative to the controls. These findings provide evidence that intervention of SOCS5 expression in T cells affects innate immunity, which highlight a novel role of T cells during sepsis.