Invasive pneumococcal disease in patients infected with HIV: still a threat in the era of highly active antiretroviral therapy

Microbiomes Detected by Bronchoalveolar Lavage Fluid Metagenomic Next-Generation Sequencing among HIV-Infected and Uninfected Patients with Pulmonary Infection

Comparison of lung microbiomes between HIV-infected and uninfected patients with pulmonary infection by metagenomic next-generation sequencing (mNGS) has not been described in China. The lung microbiomes detected in bronchoalveolar fluid (BALF) by mNGS among HIV-infected and uninfected patients with pulmonary infection were reviewed in the First Hospital of Changsha between January 2019 and June 2022. In total, 476 HIV-infected and 280 uninfected patients with pulmonary infection were enrolled. Compared with HIV-uninfected patients, the proportions of Mycobacterium (P = 0.011), fungi (P < 0.001), and viruses (P < 0.001) were significantly higher in HIV-infected patients. The higher positive rate of Mycobacterium tuberculosis (MTB; P = 0.018), higher positive rates of Pneumocystis jirovecii and Talaromyces marneffei (all P < 0.001), and higher positive rate of cytomegalovirus (P < 0.001) contributed to the increased proportions of Mycobacterium, fungi, and viruses among HIV-infected patients, respectively. The constituent ratios of Streptococcus pneumoniae (P = 0.007) and Tropheryma whipplei (P = 0.002) in the bacteria spectrum were significantly higher, while the constituent ratio of Klebsiella pneumoniae (P = 0.005) was significantly lower in HIV-infected patients than in HIV-uninfected patients. Compared with HIV-uninfected patients, the constituent ratios of P. jirovecii and T. marneffei (all P < 0.001) in the fungal spectrum were significantly higher, while the constituent ratios of Candida and Aspergillus (all P < 0.001) were significantly lower in HIV-infected patients. In comparison to HIV-infected patients without antiretroviral therapy (ART), the proportions of T. whipplei (P = 0.001), MTB (P = 0.024), P. jirovecii (P < 0.001), T. marneffei (P < 0.001), and cytomegalovirus (P = 0.008) were significantly lower in HIV-infected patients on ART. Significant differences in lung microbiomes exist between HIV-infected and uninfected patients with pulmonary infection, and ART influences the lung microbiomes among HIV-infected patients with pulmonary infection. IMPORTANCE A better understanding of lung microorganisms is conducive to early diagnosis and treatment and will improve the prognosis of HIV-infected patients with pulmonary infection. Currently, few studies have systematically described the spectrum of pulmonary infection among HIV-infected patients. This study is the first to provide comprehensive information on the lung microbiomes of HIV-infected patients with pulmonary infection (as assessed by more sensitive metagenomic next-generation sequencing of bronchoalveolar fluid) compared with those from HIV-uninfected patients, which could provide a reference for the etiology of pulmonary infection among HIV-infected patients.

Living with HIV and Getting Vaccinated: A Narrative Review

After 40 years of its appearance, human immunodeficiency virus (HIV) infection remains a leading public health challenge worldwide. Since the introduction of antiretroviral treatment (ART), HIV infection has become a chronic condition, and people living with HIV could have life expectancies close to those of the general population. People with HIV often have an increased risk of infection or experience more severe morbidity following exposure to vaccine-preventable diseases. Nowadays, several vaccines are available against bacteria and viruses. However, national and international vaccination guidelines for people with HIV are heterogeneous, and not every vaccine is included. For these reasons, we aimed to perform a narrative review about the vaccinations available for adults living with HIV, reporting the most updated studies performed for each vaccine among this population. We performed a comprehensive literature search through electronic databases (Pubmed-MEDLINE and Embase) and search engines (Google Scholar). We included English peer-reviewed publications (articles and reviews) on HIV and vaccination. Despite widespread use and guideline recommendations, few vaccine trials have been conducted in people with HIV. In addition, not all vaccines are recommended for people with HIV, especially for those with low CD4 cells count. Clinicians should carefully collect the history of vaccinations and patients' acceptance and preferences and regularly check the presence of antibodies for vaccine-preventable pathogens.

Risk Factors for Severe Coronavirus Disease 2019 Among Human Immunodeficiency Virus-Infected and -Uninfected Individuals in South Africa, April 2020-March 2022: Data From Sentinel Surveillance

Background

Data on risk factors for coronavirus disease 2019 (COVID-19)-associated hospitalization and mortality in high human immunodeficiency virus (HIV) prevalence settings are limited.

Methods

Using existing syndromic surveillance programs for influenza-like-illness and severe respiratory illness at sentinel sites in South Africa, we identified factors associated with COVID-19 hospitalization and mortality.

Results

From April 2020 through March 2022, severe acute respiratory syndrome coronavirus 2 was detected in 24.0% (660 of 2746) of outpatient and 32.5% (2282 of 7025) of inpatient cases. Factors associated with COVID-19-associated hospitalization included the following: older age (25-44 [adjusted odds ratio {aOR}= 1.8, 95% confidence interval (CI) = 1.1-2.9], 45-64 [aOR = 6.8, 95% CI = 4.2-11.0] and ≥65 years [aOR = 26.6, 95% CI = 14.4-49.1] vs 15-24 years); black race (aOR, 3.3; 95% CI, 2.2-5.0); obesity (aOR, 2.3; 95% CI, 1.4-3.9); asthma (aOR, 3.5; 95% CI, 1.4-8.9); diabetes mellitus (aOR, 5.3; 95% CI, 3.1-9.3); HIV with CD4 ≥200/mm³ (aOR, 1.5; 95% CI, 1.1-2.2) and CD4 <200/mm³ (aOR, 10.5; 95% CI, 5.1-21.6) or tuberculosis (aOR, 12.8; 95% CI, 2.8-58.5). Infection with Beta (aOR, 0.5; 95% CI, .3-.7) vs Delta variant and being fully vaccinated (aOR, 0.1; 95% CI, .1-.3) were less associated with COVID-19 hospitalization. In-hospital mortality was increased in older age (45-64 years [aOR, 2.2; 95% CI, 1.6-3.2] and ≥65 years [aOR, 4.0; 95% CI, 2.8-5.8] vs 25-44 years) and male sex (aOR, 1.3; 95% CI, 1.0-1.6) and was lower in Omicron-infected (aOR, 0.3; 95% CI, .2-.6) vs Delta-infected individuals.

Conclusions

Active syndromic surveillance encompassing clinical, laboratory, and genomic data identified setting-specific risk factors associated with COVID-19 severity that will inform prioritization of COVID-19 vaccine distribution. Elderly people with tuberculosis or people with HIV, especially severely immunosuppressed, should be prioritized for vaccination.

Trends in the Epidemiology and Outcomes of Pneumocystis Pneumonia among Human Immunodeficiency Virus (HIV) Hospitalizations

Introduction: Pneumocystis Pneumonia (PCP) is a common opportunistic infection among people living with the human immunodeficiency virus (HIV). This study’s objective was to assess temporal trends in PCP epidemiology among hospitalized patients with HIV/AIDS in the US and to compare data for hospitalizations with HIV with PCP to those without PCP. Methods: The national inpatient sample (NIS) data were analyzed from 2002−2014. The discharge coding identified hospitalized patients with HIV or AIDS and with or without PCP. Results: We identified 3,011,725 hospitalizations with HIV/AIDS during the study period; PCP was present in 5% of the patients with a diagnosis of HIV. The rates of PCP progressively declined from 6.7% in 2002 to 3.5 % in 2014 (p < 0.001). Overall mortality in patients with HIV was 3.3% and was significantly higher in those with PCP than without PCP (9.9% vs. 2.9%; p < 0.001). After adjusting for demographics and other comorbidities, PCP had higher odds of hospital mortality 3.082 (OR 3.082; 95% CI, 3.007 to 3.159; p < 0.001). Conclusion: From 2002 to 2014, the rate of PCP in HIV patients has decreased significantly in the United States but is associated with substantially higher mortality.

Evaluation of effectiveness, safety and cost-benefit of the 23- valent pneumococcal capsular polysaccharide vaccine for HIV-Infected patients

INTRODUCTION

Due to the lack of understanding of the protective effects and safety of 23-valent pneumococcal polysaccharide vaccine (PPV23) in immune-deficient populations, the vaccination rate of PPV23 among HIV-infected patients is still very low in China. The main objectives of this study were to determine whether the efforts to assess measures for the prevention of pneumococcal pneumonia are still worthwhile, and provide designated vaccination program of HIV-infected persons for government policy based on.

METHODS

60 HIV-infected adults in Lanshan county who had never been vaccinated with any pneumococcal vaccine were enrolled in this study, voluntary vaccination of PPV23 and One-year follow-up after vaccination can be completed.

RESULT

76.67% patients (46/60) had serologic response at 12 months after vaccine, CD4 count(≤500 cells/ul or > 500 cells/ul) and Month from diagnosis to first antiviral therapy (≤1 month or > 1 month) were related to antibody responses (p < 0.05).In this study, PPV23 was well tolerated, no adversereaction was reported.11 Streptococcus pneumoniae pneumonia (9.17%,11/120) occurred in the Unvaccinated group and 1 case(1.67%,1/60)in the vaccination group within one year after vaccination(Fisher's exact probability, P = 0.225). The VE was 81.79%. The per capita benefit was 39.32 dollars, thebenefit-costratio = 1.19. There are significant statistical differences between the vaccinated group and the non-vaccinated group in outpatient costs (p < 0.05, 95 %CI: 9.29-32.11), Medicine costs (p = 0.017, 95 %CI: 2.47-24.44), and disease related indirect costs (p = 0.038, 95 %CI: 0.93-33.63) within one year of vaccination.

CONCLUSION

Our study results showed that PPV23 can be safely and effectively administered to HIV-1 infected individuals and effectively preventing Streptococcal pneumonia. Considering the cost-benefit of vaccination among HIV-infected persons, as it has been reported in our study, it is necessary to promote the widespread use of the vaccine among HIV-infected persons in the future.

Burden of pneumococcal disease among adults in Southern Europe (Spain, Portugal, Italy, and Greece): a systematic review and meta-analysis

The aim was to summarize pneumococcal disease burden data among adults in Southern Europe and the potential impact of vaccines on epidemiology. Of 4779 identified studies, 272 were selected. Invasive pneumococcal disease (IPD) incidence was 15.08 (95% CI 11.01-20.65) in Spain versus 2.56 (95% CI 1.54-4.24) per 100,000 population in Italy. Pneumococcal pneumonia incidence was 19.59 (95% CI 10.74-35.74) in Spain versus 2.19 (95% CI 1.36-3.54) per 100,000 population in Italy. Analysis of IPD incidence in Spain comparing pre-and post- PCV7 and PCV13 periods unveiled a declining trend in vaccine-type IPD incidence (larger and statistically significant for the elderly), suggesting indirect effects of childhood vaccination programme. Data from Portugal, Greece and, to a lesser extent, Italy were sparse, thus improved surveillance is needed. Pneumococcal vaccination uptake, particularly among the elderly and adults with chronic and immunosuppressing conditions, should be improved, including shift to a higher-valency pneumococcal conjugate vaccine when available.

Pneumococcal endocarditis involving the pulmonic valve in a patient with HIV

Infective endocarditis in drug users commonly targets the tricuspid valves, whereas pulmonic valve endocarditis is a rare occurrence. Staphylococcus aureus rather than Streptococcus species is the culprit organism. Streptococcal pneumonia is also not commonly seen as an etiological agent for endocarditis. Here we present a case of a 57-year-old man with a history of HIV infection on antiretroviral therapy who was admitted for sepsis and found to have pneumococcal bacteremia with vegetation on a pulmonic valve. He had been vaccinated with both pneumococcal conjugate vaccine 13 and pneumococcal polysaccharide vaccine 23 at the time of his HIV diagnosis. Pulmonic valve endocarditis is unusual in the setting of pneumococcal bacteremia in HIV patients previously vaccinated for pneumococcal disease.

Invasive Pneumococcal Disease in People With Human Immunodeficiency Virus in England, 1999-2017

BACKGROUND

The 7-valent and 13-valent pneumococcal conjugate vaccines (PCVs) were introduced into the UK childhood immunization program in 2006 and 2010, respectively, with high effectiveness and resulting in both direct and indirect protection. We describe the epidemiology of invasive pneumococcal disease (IPD) in adults with human immunodeficiency virus (HIV) in England following the introduction of both PCVs.

METHODS

Data on a national cohort of people with HIV were linked to confirmed IPD cases in adults aged ≥ 15 years during 1999-2017. Date of HIV infection was estimated using a CD4 slope decline algorithm.

RESULTS

Among 133 994 adults with HIV, 1453 developed IPD during 1999-2017, with 70% (1016/1453) developing IPD ≥ 3 months after their HIV diagnosis. IPD and HIV were codiagnosed within 90 days in 345 (24%) individuals. A missed opportunity for earlier HIV diagnosis was identified in 6% (89/1453), mostly in earlier years. IPD incidence in people with HIV increased from 147/100 000 in 1999 to 284/100 000 in 2007 before declining and stabilizing between 92 and 113/100 000 during 2014-2017. Mean annual IPD incidence was lower among those receiving antiretroviral therapy during 2014-17 (68 vs 720/100 000; incidence rate ratio [IRR] 9.3; 95% confidence interval [CI], 7.3-11.8; P < .001) and was markedly lower in those with a suppressed viral load (50 vs 523/100 000; IRR 10.4; 95% CI, 7.6-14.1; P < .001). The latter group still had 4.5-fold higher (95% CI, 3.8-5.3; P < .001) IPD incidence compared to the general population (11.2/100 000).

CONCLUSIONS

IPD incidence among people with HIV reduced after PCV13 introduction and has remained stable. Adults presenting with IPD should continue to be tested for HIV infection.

Residual immune dysfunction under antiretroviral therapy

The usage of combination antiretroviral therapy in people with HIV (PWH) has incited profound improvement in morbidity and mortality. Yet, PWH may not experience full restoration of immune function which can manifest with non-AIDS comorbidities that frequently associate with residual inflammation and can imperil quality of life or longevity. In this review, we discuss the pathogenesis underlying chronic inflammation and residual immune dysfunction in PWH, as well as potential therapeutic interventions to ameliorate them and prevent incidence or progression of non-AIDS comorbidities. Current evidence advocates that early diagnosis and prompt initiation of therapy at high CD4 counts may represent the best available approach for an improved immune recovery in PWH.

Does cotrimoxazole prophylaxis in HIV patients increase the drug resistance of pneumococci? A comparative cross-sectional study in southern Ethiopia

BACKGROUND

Infections caused by antibiotic-resistant bacteria results in high rates of morbidity and mortality. Although the prolonged cotrimoxazole (CTX) prophylaxis is arguably associated with the risk of increasing drug resistance in the common pathogens, information regarding its impact on Streptococci pneumoniae / pneumococcus is very limited.

OBJECTIVE

This study was conducted to investigate the effect of cotrimoxazole prophylaxis on nasopharyngeal colonization rate and antimicrobial resistance using Streptococci pneumoniae (pneumococcus) as an indicator organism among HIV patients in Arba Minch, Ethiopia.

MATERIALS AND METHODS

A comparative cross-sectional study was designed and conducted among HIV patients attending the Anti-Retroviral Treatment (ART) clinic of Arba Minch General Hospital (AMGH) from April 01 to August 31, 2018. A total of 252 participants were systematically selected and clustered into two study groups based on their CTX prophylaxis status, one taking CTX prophylaxis, and the second one, the control group (without prophylaxis). A structured questionnaire was used to collect socio-demographic and clinical data from patients. A nasopharyngeal swab was collected and cultured for pneumococcal isolation and identification in accordance with standard microbiological techniques. An antibiotics sensitivity test was performed according to the CLSI guidelines. Data were analyzed using the Statistical package for social science (SPSS) version 20. The primary outcome was determined using logistic regression analysis.

RESULTS

Of the 252 enrolled HIV patients (mean age (37.38± 9.03 years), 144 (57.14%) were males. The overall, nasopharyngeal colonization rate of S. pneumoniae was 13.5% (95% CI: 8.4-15.6). Asymptomatic pneumococcal carriage rates among patients on CTX prophylaxis and the control group were 16.3%, and 10.3% respectively (p-value = 0.03). Regarding the risk factors analyzed, CTX prophylaxis (AOR: 2.2; 95% CI: 1.05-4.9) and gender (AOR: 2.5; 95% CI: 1.09-5.93) were significantly associated with pneumococcal colonization, showing a male preponderance. Cotrimoxazole-resistant pneumococci were 85.7% vs. 47.4% in the prophylaxis group and the control group respectively and it was statistically significant (AOR: 6.7; 95% CI: 1.3-36). Percentages of multi-drug resistant isolates in these two groups were 38.09 and 15.38 respectively (p-value = 0.04). Among the CTX resistant pneumococci isolates, 85% were also found to be co-resistant towards penicillin and was statistically significant.

CONCLUSION

The percentage prevalence of nasopharyngeal pneumococci colonization was higher in patients taking CTX prophylaxis. It was noted that CTX prophylaxis eventually results in the selection of cotrimoxazole resistance and multi-drug resistance in pneumococci. There is evidence of existing cross-resistance between cotrimoxazole and penicillin antibiotics. Therefore, CTX prophylaxis must be administered judiciously. Surveillance for antimicrobial susceptibility is warranted where the prophylaxis is common.

Pneumococcal vaccination in adult people living with HIV on suppressive antiretroviral therapy: a case-control study

There is little information on the effectiveness of the pneumococcal vaccines (PVs), especially for the pneumococcal conjugate vaccines (PCVs), in HIV-infected patients in the modern antiretroviral era. This is a case–control study where cases were people living with HIV (PLWH) with confirmed pneumococcal infection (CPI) and controls were PLWH without CPI matched with cases by gender and year of HIV diagnosis. The selection process was blinded to the study factor (vaccination). Sample size estimation yielded 61 cases and 183 controls. We analyzed the effect of PV on CPI using Cox proportional-hazards regression model with time-dependent covariates. We included 256 subjects: 64 cases, and 192 controls. PVs had been administered to 115 (45%) patients. Only the modified Charlson Comorbidity Index (HR 1.16, 95%CI 1.06–1.27, P = 0.001) and the CD4 nadir (HR 0.99, 95% CI 0.98–0.99, P = 0.001) were independently associated with CPI. Receipt of PV was not associated with CPI after adjusting in the multivariate model with time protection as a dependent covariate (HR 0.65, 95% CI 0.35–1.32 P = 0.250). We also investigated the influence of different immunization schedules. In an adjusted model, we found no evidence of protection against CPI, including double immunization schedules (HR 0.42 95%CI 0.15–1.19 P = 0.102). In this case–control study, we could not show an association between pneumococcal vaccination and confirmed pneumococcal infection, although a protective effect of particular schedules of immunization cannot be ruled out.

Viro-immunological outcomes after 13-valent pneumococcal vaccination in HIV-1-infected individuals on stable virological suppression

BACKGROUND

Very limited data are available on the immunovirological outcomes after 13-valent pneumococcal conjugate vaccine (PCV13) in antiretroviral therapy (ART)-treated patients. The aim of this study was to assess the immune-virological outcomes in HIV-1-infected ART-treated patients on stable virological suppression who underwent pneumococcal conjugate vaccination.

METHODS

Retrospective, cohort study on ART-treated HIV-1-infected individuals, age at least 18 years, with three consecutive determinations of HIV-RNA less than 50 copies/ml before the administration of PCV13 (baseline) at San Raffaele Hospital and with at least two HIV-RNA values after vaccination.

RESULTS

Overall 1197 patients underwent PCV13 vaccination. During 6-month of follow-up (594 person-years of follow-up, PYFU), 12 confirmed virological failure and 35 viral blips were observed; the overall incidence rate of confirmed virological failure was 2.02 (95% confidence interval: 0.88-3.16) per 100-PYFU and the incidence rate of viral blips was 5.89 (95% confidence interval: 3.94-7.84) per 100-PYFU. Median CD4 cell count change from baseline at 6 months was +10 cells/μl (interquartile range -67, +111; P = 0.0002). Median change in CD4/CD8 ratio was +0.02 (interquartile range -0.06, +0.11; P < 0.001).

CONCLUSION

Viral blips and confirmed virological failures were rarely observed in patients on stable virological suppression in the first 6 months following vaccination with PCV13. In addition, no decrease of CD4 cell count and CD4/CD8 ratio was recorded.

HIV gp120 in the Lungs of Antiretroviral Therapy-treated Individuals Impairs Alveolar Macrophage Responses to Pneumococci

RATIONALE

People living with HIV are at significantly increased risk of invasive pneumococcal disease, despite long-term antiretroviral therapy (ART). The mechanism explaining this observation remains undefined.

OBJECTIVES

To determine if apoptosis-associated microbicidal mechanisms, required to clear intracellular pneumococci that survive initial phagolysosomal killing, are perturbed.

METHODS

Alveolar macrophages (AM) were obtained by BAL from healthy donors or HIV-1-seropositive donors on long-term ART with undetectable plasma viral load. Monocyte-derived macrophages (MDM) were obtained from healthy donors and infected with HIV-1_BaL or treated with gp120. Macrophages were challenged with opsonized serotype 2 Streptococcus pneumoniae and assessed for apoptosis, bactericidal activity, protein expression, and mitochondrial reactive oxygen species (mROS). AM phenotyping, ultrasensitive HIV-1 RNA quantification, and gp120 measurement were also performed in BAL.

MEASUREMENTS AND MAIN RESULTS

HIV-1_BaL infection impaired apoptosis, induction of mROS, and pneumococcal killing by MDM. Apoptosis-associated pneumococcal killing was also reduced in AM from ART-treated HIV-1-seropositive donors. BAL fluid from these individuals demonstrated persistent lung CD8⁺ T lymphocytosis, and gp120 or HIV-1 RNA was also detected. Despite this, transcriptional activity in AM freshly isolated from people living with HIV was broadly similar to healthy volunteers. Instead, gp120 phenocopied the defect in pneumococcal killing in healthy MDM through post-translational modification of Mcl-1, preventing apoptosis induction, caspase activation, and increased mROS generation. Moreover, gp120 also inhibited mROS-dependent pneumococcal killing in MDM.

CONCLUSIONS

Despite ART, HIV-1, via gp120, drives persisting innate immune defects in AM microbicidal mechanisms, enhancing susceptibility to pneumococcal disease.

Long-Term Serological Response to 13-Valent Pneumococcal Conjugate Vaccine Versus 23-Valent Polysaccharide Vaccine in HIV-Infected Adults

Introduction

Long-term comparative immunologic response to 13-valent pneumococcal conjugate vaccine (PCV13) versus 23-valent polysaccharide vaccine (PPV23) among HIV-infected adults has not yet been investigated.

Methods

In this prospective pilot study, we quantified in HIV-positive adults serotype-specific IgG concentrations of the 12 pneumococcal serotypes shared by both vaccines 5 years after vaccination with two doses of PCV13 8 weeks apart (group 1) or one dose of PPV23 (group 2) and compared them with those assessed prior to vaccination (BL) and after 1 year (T1). Comparison of immunogenicity was based on geometric mean concentration (GMC), proportion of individuals with ≥ twofold increase from BL in specific antibody concentration against ≥ 2 serotypes and percentage of individuals with serotype-specific IgG ≥ 0.35 μg/ml, ≥ 1 μg/ml and ≥ individual serotype-specific correlates of protection.

Results

We included 91 subjects (median CD4⁺ 650 cells/µl, > 90% with HIV-RNA < 50 copies/ml); patients in groups 1 (n = 42) and 2 (n = 49) were homogeneous for the main characteristics. GMCs were significantly higher in the PCV13 group than in the PPV23 group for serotype 19F (p = 0.003). Both vaccines revealed higher significant GMCs to most serotypes compared with BL, i.e., eight in group 1 vs. seven in group 2. With respect to T1, GMCs decreased significantly in the PCV13 group for eight vs. ten serotypes in the PPV23 group. More participants in the PCV13 group had ≥ 2 increase from BL in antibody levels to ≥ 2 serotypes compared with the PPV23 group (78.6% vs. 59.2%, p = 0.042). Overall, the percentage of subjects with serotype-specific IgG ≥ 0.35 μg/ml, ≥ 1 μg/ml and ≥ individual serotype-specific correlates of protection was similar between groups.

Conclusion

In this study with HIV-positive adults with a favorable viro-immunologic profile, both vaccines were shown to achieve a long-term durable serologic response. We found minor differences in immunogenicity between the two vaccines, which favored PCV13 over PPV23 5 years after immunization.

Trial Registration

ClinicalTrials.gov identifier, NCT02123433.

Electronic supplementary material

The online version of this article (10.1007/s40121-019-0256-z) contains supplementary material, which is available to authorized users.

Treating bacterial pneumonia in people living with HIV

Introduction: Bacterial pneumonia remains an important cause of morbidity and mortality in people living with HIV (PLWH) in the antiretroviral therapy (ART) era. In addition to being immunocompromised, as reflected by low CD4 cell counts and elevated HIV viral loads, PLWH often have other behaviors associated with an increased risk of pneumonia including smoking and injected drug use. As PLWH are aging, comorbid conditions such as chronic obstructive pulmonary disease (COPD), cancers, and cardiovascular, renal and liver diseases are emerging as additional risk factors for pneumonia. Pathogens are often similar to those in HIV-uninfected individuals; however, PLWH are at risk for unusual and/or multi-drug resistant organisms causing bacterial pneumonia based, in part, on their CD4 cell counts and other exposures. Areas covered: In this review, we focus on the recognition and management of bacterial community-acquired pneumonia (CAP) in PLWH. Along with antimicrobial treatment, we discuss prevention strategies such as vaccination and smoking cessation. Expert opinion: Early initiation of ART after HIV infection can decrease the risk of pneumonia. Improved efforts at vaccination, smoking cessation, and reduction of other substance use are urgently needed in PLWH to decrease the risk for bacterial pneumonia. As PLWH are aging, comorbidities are additional risk factors for bacterial CAP.

Incidence and risk factors for invasive pneumococcal disease in HIV-positive individuals in the era of highly active antiretroviral therapy

Invasive pneumococcal diseases (IPDs) remain a significant cause of morbidity and mortality in human immunodeficiency virus (HIV)-positive individuals despite the widespread use of highly active antiretroviral therapy (HAART) and availability of pneumococcal vaccines. The aim of this study was to measure temporal trends in incidence and risk factors for IPD (defined as culture of Streptococcus pneumoniae from blood, cerebrospinal fluid or both) in a cohort of HIV-positive patients attending an ambulatory HIV care centre in Dublin, Ireland over a 10-year period 2006-2015. Incidence of IPD was determined as events per 100,000 person-years' follow-up. Poisson regression was used to assess linear trend in incidence over time. A nested case-control study (four controls per case) was undertaken to assess risk factors for IPD. Forty-seven episodes of IPD were identified in 42 HIV-positive individuals (median [IQR] age 38 years [33-43], 69% male, 86% injecting drug users (IDUs), median CD4 T-cell count 213 cells/mm³) over 16,008 person-years' follow-up (overall incidence rate 293/100,000 person-years). Three patients had two episodes and one patient had three episodes of IPD during the study period. The overall case fatality rate was 15% (95% confidence interval [CI] 4-24%). The incidence of IPD per 100,000 person-years decreased from 728 (95% CI, 455-1002), to 242 (95% CI, 120-365) to 82 (95% CI, 40-154) in calendar periods 2006-2008, 2009-2012 and 2013-2015, respectively (p < 0.01 for linear trend). Older age (p = 0.02), male gender (p = 0.05), detectable HIV viral load (p < 0.01) and non-receipt of pneumococcal vaccine (p = 0.03) were associated with IPD while IDU as risk of acquisition of HIV was of borderline significance (p = 0.06). HIV-positive individuals remain at greater risk of IPD compared to the general population. Pneumococcal vaccine should be seen as a priority to ensure optimal protection for HIV-positive patients.

Incidence of invasive pneumococcal disease in immunocompromised patients: A systematic review and meta-analysis

BACKGROUND

Invasive pneumococcal disease (IPD) is associated with high morbidity and mortality, with immunocompromised patients (ICPs) at particular risk. Therefore, guidelines recommend pneumococcal vaccination for these patients. However, guidelines are scarcely underpinned with references to incidence studies of IPD in this population. This, potentially results in unawareness of the importance of vaccination and low vaccination rates. The objective of this systematic review and meta-analysis was to assess the incidence of IPD in ICPs.

METHODS

We systematically searched PubMed and Embase to identify studies in English published before December 6th, 2017 that included terms related to 'incidence', 'rate', 'pneumococcal', 'pneumoniae', 'meningitis', 'septicemia', or 'bacteremia'. We focused on patients with HIV, transplantation and chronic inflammatory diseases.

RESULTS

We included 45 studies in the systematic review reporting an incidence or rate of IPD, defined as isolation of Streptococcus pneumoniae from a normally sterile site. Random effects meta-analysis of 38 studies showed a pooled IPD incidence of 331/100,000 person years in patients with HIV in the late-antiretroviral treatment era in non-African countries, and 318/100,000 in African countries; 696 and 812/100,000 in patients who underwent an autologous or allogeneic stem cell transplantation, respectively; 465/100,000 in patients with a solid organ transplantation; and 65/100,000 in patients with chronic inflammatory diseases. In healthy control cohorts, the pooled incidence was 10/100,000.

DISCUSSION

ICPs are at increased risk of contracting IPD, especially those with HIV, and those who underwent transplantation. Based on our findings, we recommend pneumococcal vaccination in immunocompromised patients.

PROSPERO REGISTRATION

ID: CRD42016048438.

Burden of pneumococcal community-acquired pneumonia in adults across Europe: A literature review

BACKGROUND

The burden of community-acquired pneumonia (CAP) caused by Streptococcus pneumoniae (pneumococcus) among adults in Europe is poorly defined.

METHODS

Structured searches of PubMed were conducted to identify the incidence of pneumococcal CAP among adults across Europe.

RESULTS

The overall incidence rates for CAP was 68-7000 per 100,000 and the incidence in hospitalised CAP cases of all causes was 16-3581 per 100,000. In general the incidence of CAP increased consistently with age. Available data indicated higher burdens of pneumococcal CAP caused in groups with more comorbidities. Most cases of pneumococcal CAP (30%-78%) were caused by serotypes covered by PCV13 vaccine; the incidence of PCV13-related pneumonia decreased after the introduction of childhood vaccination.

CONCLUSIONS

We observed a high burden adult pneumococcal CAP in Europe despite use of the 23-valent pneumococcal polysaccharide vaccine, particularly in elderly patients with comorbidities. CAP surveillance presented wide variations across Europe. Pneumococcal CAP has to be monitored very carefully due to the possible effect of current vaccination strategies.

Invasive pneumococcal disease (IPD) in HIV infected patients in Israel since the introduction of pneumococcal conjugated vaccines (PCV): Analysis of a nationwide surveillance study, 2009-2014

STUDY AIM

to assess the incidence, risk factors and outcome of invasive pneumococcal disease (IPD) among the Israeli HIV population. A matched case-control study nested in a nationwide, prospective, population-based, cohort of adult IPD was performed. In addition, the HIV-IPD patients were compared to the general adult HIV population in Israel.

STUDY PERIOD

from the introduction of PCV into the national immunization program (NIP) in July 2009 to June 2014. Each HIV patient within the IPD cohort was matched to 4 non-HIV controls. Serotyping was performed by a central laboratory using the Quellung reaction. Thirty-five IPD episodes in 33 HIV patients were identified, with a median annual incidence of 128/100,000 HIV+ persons compared to 5.1/100,000 in the age-matched, non-HIV population. Compared to the general HIV population, HIV-IPD patients practiced intravenous drug use more frequently and originated from a country with generalized epidemic (OGE), mainly non-citizens lacking medical insurance. The proportion of men who have sex with men (MSM) was lower than in the general HIV population. Pneumonia was the most common clinical presentation (81%), while meningitis occurred in only one patient. Outcomes were similar to those of the IPD non-HIV population. Nineteen serotypes were identified, of which only 42% were covered by PCV13 vaccine. By 2014, none of the HIV-IPD cases belonged to serotypes covered by PCV13. In conclusion, most HIV IPD cases were from marginalized populations with poor access to health services. A decrease in IPD cases covered by PCV 13 was observed.

Dysregulation of Alveolar Macrophage PPARγ, NADPH Oxidases, and TGFβ1 in Otherwise Healthy HIV-Infected Individuals

Despite antiretroviral therapy (ART), respiratory infections increase mortality in individuals living with chronic human immunodeficiency virus (HIV) infection. In experimental and clinical studies of chronic HIV infection, alveolar macrophages (AMs) exhibit impaired phagocytosis and bacterial clearance. Peroxisome proliferator-activated receptor (PPAR)γ, NADPH oxidase (Nox) isoforms Nox1, Nox2, Nox4, and transforming growth factor-beta 1 (TGFβ₁) are critical mediators of AM oxidative stress and phagocytic dysfunction. Therefore, we hypothesized that HIV alters AM expression of these targets, resulting in chronic lung oxidative stress and subsequent immune dysfunction. A cross-sectional study of HIV-infected (n = 22) and HIV-uninfected (n = 6) subjects was conducted. Bronchoalveolar lavage (BAL) was performed, and AMs were isolated. Lung H₂O₂ generation was determined by measuring H₂O₂ in the BAL fluid. In AMs, PPARγ, Nox1, Nox2, Nox4, and TGFβ₁ mRNA (quantitative real-time polymerase chain reaction) and protein (fluorescent immunomicroscopy) levels were assessed. Compared with HIV-uninfected (control) subjects, HIV-infected subjects were relatively older and the majority were African American; ∼86% were on ART, and their median CD4 count was 445, with a median viral load of 0 log copies/ml. HIV infection was associated with increased H₂O₂ in the BAL, decreased AM mRNA and protein levels of PPARγ, and increased AM mRNA and protein levels of Nox1, Nox2, Nox4, and TGFβ₁. PPARγ attenuation and increases in Nox1, Nox2, Nox4, and TGFβ₁ contribute to AM oxidative stress and immune dysfunction in the AMs of otherwise healthy HIV-infected subjects. These findings provide novel insights into the molecular mechanisms by which HIV increases susceptibility to pulmonary infections.

Enhanced FCGR2A and FCGR3A signaling by HIV viremic controller IgG

HIV-1 viremic controllers (VC) spontaneously control infection without antiretroviral treatment. Several studies indicate that IgG Abs from VCs induce enhanced responses from immune effector cells. Since signaling through Fc-γ receptors (FCGRs) modulate these Ab-driven responses, here we examine if enhanced FCGR activation is a common feature of IgG from VCs. Using an infected cell-based system, we observed that VC IgG stimulated greater FCGR2A and FCGR3A activation as compared with noncontrollers, independent of the magnitude of HIV-specific Ab binding or virus neutralization activities. Multivariate regression analysis showed that enhanced FCGR signaling was a significant predictor of VC status as compared with chronically infected patients (CIP) on highly active antiretroviral therapy (HAART). Unsupervised hierarchical clustering of patient IgG functions primarily grouped VC IgG profiles by enhanced FCGR2A, FCGR3A, or dual signaling activity. Our findings demonstrate that enhanced FCGR signaling is a common and significant predictive feature of VC IgG, with VCs displaying a distinct spectrum of FCGR activation profiles. Thus, profiling FCGR activation may provide a useful method for screening and distinguishing protective anti-HIV IgG responses in HIV-infected patients and in monitoring HIV vaccination regimens.

HIV-related pneumococcal disease prevention in adults

INTRODUCTION

HIV-infected persons are particularly susceptible to the development of severe pneumococcal disease, even in the setting of combination antiretroviral therapy (cART), due to slow, incomplete recovery of anti-pneumococcal host defenses. This risk is increased by avoidable aspects of lifestyle, particularly smoking, which intensify immunosuppression. Clearly, more effective preventive measures are needed to counter this threat. Areas covered: This is a detailed review of the published literature focusing on currently available strategies for prevention of pneumococcal infection in HIV-infected patients, including cotrimoxazole prophylaxis, cART, pneumococcal vaccination, and smoking cessation strategies. This is preceded by a consideration of the epidemiology, clinical presentation, risk factors, and outcome of pneumococcal disease. Expert commentary: Cotrimoxazole prophylaxis has been shown to reduce morbidity and mortality in HIV-infected patients, although there is inconsistent data on the preventive efficacy against pneumococcal infections. Some recent studies have documented unchanged incidences of IPD in adult patients in the cART era. With regard to pneumococcal vaccination, routine acceptance of the efficacy of the PCV13/PPV23 sequential administration prime-boost strategy awaits the outcome of clinical trials in those with HIV infection. Smoking cessation, and discontinuation of excessive alcohol consumption and intravenous drug abuse, are priority strategies to prevent severe pneumococcal infection.

Immunization of HIV-infected adult patients - French recommendations

Human immunodeficiency virus (HIV)-infected patients remain at increased risk of infection including vaccine-preventable diseases. Vaccines are therefore critical components in the protection of HIV-infected patients from an increasing number of preventable diseases. However, missed opportunities for vaccination among HIV-infected patients persist and vaccine coverage in this population could be improved. This article presents the French recommendations regarding immunization of HIV-infected adults in the light of the evidence-based literature on the benefits and the potential risks of vaccines among this vulnerable population.

The Early Adaptive Immune Response in the Pathophysiological Process of Pneumococcal Meningitis

BACKGROUND

 The adaptive immune system has been considered to play a minimal role in the early host response during bacterial meningitis.

METHODS

 We investigated the progression and outcome of pneumococcal meningitis in Rag1^-/- mice lacking functional B and T cells by assessing overall and symptom-free survival, bacteriological and histological studies, as well as flow cytometry and measurements of proinflammatory mediators.

RESULTS

 The intracerebral injection of S. pneumoniae D39 induced the recruitment of B and T cells (CD4⁺, γδ and natural killer) into the brain of wild-type mice. Mice with no functional B and T cells developed clinical symptoms and succumbed to the infection earlier than the wild-type group. In the CNS, Rag1^-/- mice showed lower levels of interleukin 1β, reduced microglial proliferation, and impaired granulocyte recruitment with an earlier spread of pneumococci into the bloodstream, compared with wild-type mice. Lack of B and T cells resulted in a severe impairment of bacterial clearance in blood, spleen, and liver and an exaggerated systemic inflammatory response.

CONCLUSIONS

 B and T cells are important effector cells delaying the spread of pneumococci from the brain to the systemic circulation and shaping the immune response, thereby prolonging the survival of the host in the absence of antibiotic treatment.

Antiretroviral Therapy as Prevention of … Pneumococcal Infections?

BACKGROUND

Despite antiretroviral therapy, it is generally believed that the risk for pneumococcal infections (PnIs) is high among patients infected with human immunodeficiency virus (HIV). However, most studies in this field have been conducted before 2010, and the proportion of virologically suppressed patients has drastically increased in these latter years thanks to larger indications and more effective antiretroviral regimens. This study aimed to re-evaluate the current risk of PnI among adult patients infected with HIV.

METHODS

The incidence of PnI was evaluated between 1996 and 2014 in 2 French regional hospitals. The 80 most recent cases of PnI (2000-2014) were retrospectively compared with 160 controls (HIV patients without PnI) to analyze the residual risk factors of PnI.

RESULTS

Among a mean annual follow-up cohort of 1616 patients, 116 PnIs were observed over 18 years. The risk factors of PnI among patients infected with HIV were an uncontrolled HIV infection or "classic" risk factors of PnI shared by the general population such as addiction, renal or respiratory insufficiency, or hepatitis B or C coinfection. Pneumococcal vaccination coverage was low and poorly targeted, because only 5% of the cases had been previously vaccinated. The incidence of invasive PnIs among HIV patients with a nonvirologically suppressed infection or comorbidities was 12 times higher than that reported in the general population at the country level (107 vs 9/100000 patients), whereas the incidence among virologically suppressed HIV patients without comorbidities was lower (7.6/100000 patients).

CONCLUSIONS

Human immunodeficiency virus infection no longer per se seems to be a significant risk factor for PnI, suggesting a step-down from a systematic to an "at-risk patient" targeted pneumococcal vaccination strategy.

Immunological efficacy of pneumococcal vaccine strategies in HIV-infected adults: a randomized clinical trial

The aim of this study was to compare the immunologic response to a prime-boost immunization strategy combining the 13-valent conjugate pneumococcal vaccine (PCV13) with the 23-valent polysaccharide pneumococcal vaccine (PPSV23) versus the PPSV23 alone in HIV-infected adults. HIV-infected adults were randomized to receive PCV13 at week 0 followed by PPSV23 at week 4 (n = 31, prime-boost group) or PPSV23 alone at week 4 (n = 33, PPSV23-alone group). Serotype specific IgG geometric mean concentration (GMC) and functional oposonophagocytic (OPA) geometric mean titer (GMT) were compared for 12 pneumococcal serotypes shared by both vaccines at week 8 and week 28. The prime-boost vaccine group were more likely to achieve a ≥2-fold increase in IgG GMC and a GMC >1 ug/ml at week 8 (odds ratio (OR) 2.00, 95% confidence interval (CI) 1.46-2.74, p < 0.01) and week 28 (OR 1.95, 95% CI 1.40-2.70, p < 0.01). Similarly, the prime-boost vaccine group were more likely to achieve a ≥4-fold increase in GMT at week 8 (OR 1.71, 95% CI 1.22-2.39, p < 0.01) and week 28 (OR 1.6, 95% CI 1.15-2.3, p < 0.01). This study adds to evidence supporting current pneumococcal vaccination recommendations combining the conjugate and polysaccharide pneumococcal vaccines in the United States and Europe for HIV-infected individuals.

Immunogenicity and Safety of the 13-Valent Pneumococcal Conjugate Vaccine versus the 23-Valent Polysaccharide Vaccine in Unvaccinated HIV-Infected Adults: A Pilot, Prospective Controlled Study

Objectives

Definition of the optimal pneumococcal vaccine strategy in HIV-infected adults is still under evaluation. We aimed to compare immunogenicity and safety of the 13-valent pneumococcal conjugate vaccine (PCV13) versus the 23-valent polysaccharide vaccine (PPSV23) in HIV-infected adults.

Methods

We performed a pilot, prospective controlled study enrolling HIV-infected pneumococcal vaccine-naïve outpatients, aged 18–65 years with CD4 counts ≥200 cells/μL. Eligible subjects were recruited into two parallel groups: group 1 (n = 50) received two doses of PCV13 eight weeks apart, and group 2 (n = 50) received one dose of PPSV23, as part of their standard of care. Anti-pneumococcal capsular polysaccharide immunoglobulin G concentrations were quantified by ELISA at baseline, 8, 24 and 48 weeks. Clinical and viro-immunological follow-up was performed at the same time points. Unvaccinated, age-matched HIV-negative adults (n = 100) were also enrolled as baseline controls.

Results

Pre-vaccination specific IgG titers for each pneumococcal antigen did not differ between study groups but they were constantly lower than those from the HIV-negative controls. After immunization, significant increases in IgG titers were observed in both study groups at each time point compared to baseline, but response to serotype 3 was blunted in group 1. Antibody titers for each antigen did not differ between study groups at week 48. Overall, the proportion of subjects achieving seroprotection and seroconversion to all serotypes was comparable between groups. A marked decrease in IgG levels over time was observed with both vaccines. No relevant adverse reactions were reported in either group.

Conclusions

In this population with favorable immune profile, no relevant differences were observed in immunogenicity between PCV13 and PPSV23. Both vaccines were safe and well tolerated.

Trial Registration

ClinicalTrials.gov NCT02123433

Nasopharyngeal pneumococcal carriage rates among HIV-infected adults following widespread pediatric use of conjugate pneumococcal vaccine-13

BACKGROUND

Nasopharyngeal pneumococcal carriage rates among HIV-infected adults has not been described since conjugate pneumococcal vaccine-13 (PCV13) was added to the universal infant and childhood vaccination schedule in 2010.

METHODS

HIV-infected adults presenting for routine health care visits to the Designated AIDS Center in Syracuse, NY between December 2013 and June 2015 were eligible for enrollment. Demographic, medical, and social history were recorded after obtaining informed consent. Nasopharyngeal samples were collected and cultured for the presence of Streptococcus pneumoniae using standard microbiologic techniques. Antibiotic susceptibility testing was performed using E-test→.

RESULTS

707 nasopharyngeal samples were collected from 414 HIV-infected adults. 18 samples were culture positive for S. pneumoniae; 1 (6%) isolate was of vaccine-type, 9 (50%) were non-vaccine types, and 8 (44%) were non-typeable. The 18 isolates were recovered from 15 different patients (4% of those enrolled). Three patients were culture positive for pneumococcus isolated from 2 consecutive samples, with non-typeable pneumococci identified consecutively from 2 patients and serotype 35B identified consecutively from 1 patient. The most commonly identified non-vaccine serotypes were 35B and 15B/C. Identified pneumococci were penicillin and cefotaxime susceptible.

CONCLUSION

Four percent of HIV-infected adults in our study population were colonized with S. pneumoniae. The non-vaccine serotypes 35B and 15B/C predominated.

HIV Infection and the Epidemiology of Invasive Pneumococcal Disease (IPD) in South African Adults and Older Children Prior to the Introduction of a Pneumococcal Conjugate Vaccine (PCV)

INTRODUCTION

Streptococcus pneumoniae is the commonest cause of bacteremic pneumonia among HIV-infected persons. As more countries with high HIV prevalence are implementing infant pneumococcal conjugate vaccine (PCV) programs, we aimed to describe the baseline clinical characteristics of adult invasive pneumococcal disease (IPD) in the pre-PCV era in South Africa in order to interpret potential indirect effects following vaccine use.

METHODS

National, active, laboratory-based surveillance for IPD was conducted in South Africa from 1 January 2003 through 31 December 2008. At 25 enhanced surveillance (ES) hospital sites, clinical data, including HIV serostatus, were collected from IPD patients ≥ 5 years of age. We compared the clinical characteristics of individuals with IPD in those HIV-infected and -uninfected using multivariable analysis. PCV was introduced into the routine South African Expanded Program on Immunization (EPI) in 2009.

RESULTS

In South Africa, from 2003-2008, 17 604 cases of IPD occurred amongst persons ≥ 5 years of age, with an average incidence of 7 cases per 100 000 person-years. Against a national HIV-prevalence of 18%, 89% (4190/4734) of IPD patients from ES sites were HIV-infected. IPD incidence in HIV-infected individuals is 43 times higher than in HIV-uninfected persons (52 per 100 000 vs. 1.2 per 100 000), with a peak in the HIV-infected elderly population of 237 per 100 000 persons. Most HIV-infected individuals presented with bacteremia (74%, 3 091/4 190). HIV-uninfected individuals were older; and had more chronic conditions (excluding HIV) than HIV-infected persons (39% (210/544) vs. 19% (790/4190), p<0.001). During the pre-PCV immunization era in South Africa, 71% of serotypes amongst HIV-infected persons were covered by PCV13 vs. 73% amongst HIV-uninfected persons, p = 0.4, OR 0.9 (CI 0.7-1.1).

CONCLUSION

Seventy to eighty-five percent of adult IPD in the pre-PCV era were vaccine serotypes and 93% of cases had recognized risk factors (including HIV-infection) for pneumococcal vaccination. These data describe the epidemiology of IPD amongst HIV-infected and -uninfected adults during the pre-PCV era and provide a robust baseline to calculate the indirect effect of PCV in future studies.

Pneumococcal vaccination among HIV-infected adult patients in the era of combination antiretroviral therapy

HIV-infected patients remain at higher risk for pneumococcal disease than the general population despite immune reconstitution and suppression of HIV replication with combination antiretroviral therapy. Vaccination with 23-valent pneumococcal polysaccharide vaccine (PPV23) composed of T-cell-independent antigens has been recommended to reduce the risk of pneumococcal disease in HIV-infected adults. However, given the heterogeneity of study design, execution and subjects enrolled, studies examining serological responses to PPV23 yielded conflicting results and observational studies of clinical effectiveness only provided moderate evidence to support the routine use of PPV23 in HIV-infected adults. Pneumococcal conjugate vaccine (PCV), with conjugation of the capsular polysaccharide to a protein carrier, is more immunogenic than PPV23 and has been demonstrated to protect against pneumococcal disease in HIV-infected children and recurrent invasive pneumococcal disease in HIV-infected adolescents and adults. Guidelines have recently been revised to recommend that HIV-infected patients aged 19 y or older receive one dose of 13-valent pneumococcal conjugate vaccine (PCV13) followed by a booster vaccination with PPV23. In this paper, we review the studies using different vaccination strategies to improve immunogenicity among HIV-infected adult patients.

Persisting high prevalence of pneumococcal carriage among HIV-infected adults receiving antiretroviral therapy in Malawi: a cohort study

OBJECTIVE

HIV-infected adults have high rates of pneumococcal carriage and invasive disease. We investigated the effect of antiretroviral therapy (ART) on pneumococcal carriage in HIV-infected adults prior to infant pneumococcal conjugate vaccine (PCV) rollout.

DESIGN

Observational cohort study.

METHODS

We recruited HIV-infected adults newly attending a rural HIV clinic in northern Malawi between 2008 and 2010. Nasopharyngeal samples were taken at baseline and after 6, 12, 18 and 24 months. We compared pneumococcal carriage by ART status using generalized estimated equation models adjusted for CD4 cell count, sex, seasonality, and other potential confounders.

RESULTS

In total, 336 individuals were included, of which 223 individuals started ART during follow-up. Individuals receiving ART had higher pneumococcal carriage than individuals not receiving ART (25.9 vs. 19.8%, P = 0.03) particularly for serotypes not included in PCV13 (16.1 vs. 9.6% P = 0.003). Following adjustment, increased carriage of non-PCV13 serotypes was still observed for individuals on ART, but results for all serotypes were nonsignificant [all serotypes: adjusted risk ratio (aRR) 1.22 (0.95-1.56); non-PCV13 serotypes: aRR 1.72, 95% CI 1.13-2.62].

CONCLUSION

Pneumococcal carriage in HIV-infected adults in Malawi remained high despite use of ART, consistent with failure of mucosal immune reconstitution in the upper respiratory tract. There was evidence of increased carriage of non-PCV13 serotypes. HIV-infected adults on ART could remain an important reservoir for pneumococcal diversity post infant pneumococcal vaccine introduction. Control of pneumococcal disease in African HIV remains a priority.

Trends in hospital deaths among human immunodeficiency virus-infected patients during the antiretroviral therapy era, 1995 to 2011

OBJECTIVE

Mortality in hospitalized human immunodeficiency virus (HIV)-infected patients is not well described. We sought to characterize in-hospital deaths among HIV-infected patients in the antiretroviral (ART) era and identify factors associated with mortality.

METHODS

We reviewed the medical records of hospitalized HIV-infected patients who died from January 1, 1995 to December 31, 2011 at an urban teaching hospital. We evaluated trends in early and late ART use and deaths due to acquired immunodeficiency syndrome (AIDS) and non-AIDS, and identified clinical and demographic correlates of non-AIDS deaths.

RESULTS

In-hospital deaths declined significantly from 1995 to 2011 (P < 0.0001); those attributable to non-AIDS increased (43% to 70.5%, P < 0.0001). Non-AIDS deaths were most commonly caused by non-AIDS infection (20.3%), cardiovascular (11.3%) and liver disease (8.5%), and non-AIDS malignancy (7.8%). Patients with non-AIDS compared to AIDS-related deaths were older (median age 48 vs 40 years, P < 0.0001), more likely to be on ART (74.1% vs 55.8%, P = 0.0001), less likely to have a CD4 count of <200 cells/mm(3) (47.2% vs 97.1%, P < 0.0001), and more likely to have an HIV viral load of ≤400 copies/mL (38.1% vs 4.1%, P < 0.0001). Non-AIDS deaths were associated with 4.5 and 4.2 times greater likelihood of comorbid underlying liver and cardiovascular disease, respectively.

CONCLUSIONS

Non-AIDS deaths increased significantly during the ART era and are now the most common cause of in-hospital deaths; non-AIDS infection, cardiovascular and liver disease, and malignancies were major contributors to mortality. Higher CD4 cell count, liver, and cardiovascular comorbidities were most strongly associated with non-AIDS deaths. Interventions targeting non-AIDS-associated conditions are needed to reduce inpatient mortality among HIV-infected patients.

Multidrug-Resistant Streptococcus pneumoniae Isolates from Healthy Ghanaian Preschool Children

Streptococcus pneumoniae is the cause of high mortality among children worldwide. Antimicrobial treatment and vaccination are used to control pneumococcal infections. In Ghana, data on antimicrobial resistance and the prevalence of multidrug-resistant pneumococcal clones are scarce; hence, the aim of this study was to determine the antibiogram of S. pneumoniae recovered from Ghanaian children younger than six years of age and to what extent resistances were due to the spread of certain sero- and multilocus sequence typing (MLST) types. The susceptibility of 115 pneumococcal isolates, recovered in a previous study, to six antimicrobials was determined by disk diffusion test. Overall, 90.4% of isolates were intermediate penicillin resistant, 99.1% were trimethoprim resistant, 73.0% were tetracycline resistant, and 33.9% were sulfamethoxazole resistant. Low resistance was recorded for erythromycin (2.6%) and cefotaxime (5.2%). Overall, 72.2% of isolates were resistant to penicillin (I or R) and at least two other antimicrobials. MLST of 20 isolates showing resistance to at least four antimicrobials revealed a high diversity documented by 16 different clones, none of which had previously been associated with multidrug resistance. The resistances found may have emerged due to nonprudent antimicrobial use practices and there is a need to monitor and promote prudent antimicrobial usage in Ghana.

Quantitative and Qualitative Antibody Responses to Immunization With the Pneumococcal Polysaccharide Vaccine in HIV-Infected Patients After Initiation of Antiretroviral Treatment: Results From a Randomized Clinical Trial

BACKGROUND

Pneumococcal vaccination is recommended for human immunodeficiency virus-infected (HIV+) persons; the best timing for immunization with respect to initiation of antiretroviral therapy (ART) is unknown.

METHODS

Double-blind, placebo-controlled trial in HIV+ with CD4(+) T cells/µL (CD4) ≥ 200 randomized to receive the 23-valent pneumococcal polysaccharide vaccine (PPV23) or placebo at enrollment, followed by placebo or PPV23, respectively, 9-12 months later (after ≥6 months of ART). Capsular polysaccharide-specific immunoglobin (Ig) G and IgM levels to serotypes 1, 3, 4, 6B, and 23F, and opsonophagocytic killing activity (OPA) to serotypes 6B and 23F were evaluated 1 month postvaccination.

RESULTS

One hundred seven subjects were enrolled, 72 (67.3%) were evaluable (36/group). Both groups had significant increases in pre- to 1-month postvaccination IgG levels, but negligible to IgM, and significant increases in OPA titers to serotype 6B but not to 23F. There were no significant differences between groups in serotype-specific IgM or IgG levels or OPA titers. For the combined groups, there was a significant correlation between serotype-specific IgG and OPA titers to 23F but not to 6B. There was no correlation between CD4, viral load and IgG responses.

CONCLUSIONS

In HIV+ with CD4 ≥ 200, delaying PPV23 until ≥6 months of ART does not improve responses and may lead to missed opportunities for immunization.

Delayed reconstitution of B cell immunity to pneumococcus in HIV-infected Malawian children on antiretroviral therapy

OBJECTIVE

Despite CD4(+) count restoration and viral load suppression with antiretroviral therapy (ART), HIV-infected children remain at increased risk of life-threatening infections including invasive pneumococcal disease (IPD). We therefore investigated whether persistent susceptibility to IPD following ART is associated with incomplete recovery of B-cell function.

METHODS

41 HIV-infected Malawian children commencing ART were followed-up for a 1 year period during which time blood samples were collected at 0, 3, 6 and 12 months for comprehensive immunophenotyping and pneumomococcal-specific Memory B-cell Enzyme-Linked Immunospot assays. In addition, nasopharyngeal swab samples were cultured to determine pneumococcal carriage rates.

RESULTS

Normalization of major lymphocyte subsets such as CD4(+) percentages was evident following 3 months of ART. The proportions of mature naïve B cells (CD19(+) CD10(-) CD27(-) CD21(hi)) and resting memory B cells (CD19(+) CD27(+) CD21(hi)) increased and apoptosis-prone mature activated B cells (CD19(+) CD21(lo) CD10(-)) decreased markedly by 12 months. However, in the context of high nasopharyngeal pneumococcal carriage rates (83%), restoration of pneumococcal protein antigen-specific B-cell memory was more delayed.

CONCLUSIONS

These data show that, in chronically HIV-infected children receiving ART, improvement in B-cell memory profiles and function is slower than CD4(+) T-cells. This supports early initiation of ART and informs research into optimal timing of immunization with pneumococcal vaccines.

Antibody Response is More Likely to Pneumococcal Proteins Than to Polysaccharide After HIV-associated Invasive Pneumococcal Disease

BACKGROUND

Human immunodeficiency virus (HIV)-infected individuals are at increased risk of invasive pneumococcal disease (IPD). In order to assess the immunogenicity of pneumococcal proteins and polysaccharide, we investigated protein and serotype-specific antibody responses after HIV-associated IPD.

METHODS

Specific antipneumococcal immunoglobulin G to 27 pneumococcal protein antigens and 30 serotype polysaccharides was measured in plasma before and after IPD in HIV-infected individuals and compared to HIV-infected individuals without IPD.

RESULTS

Over time, 81% of IPD cases responded to at least 1 protein compared to 51% of non-IPD controls. HIV IPD cases responded to more proteins than non-IPD controls (8.6 ± 8.4 vs 4.2 ± 7.6 proteins; P = .01), and had a significantly higher probability of yielding an antibody response to the proteins PiaA, PsaA, and PcpA. Twenty-two percent of HIV-infected individuals with IPD had a serotype-specific antibody response. Younger age at the time of IPD was the only predictor of a serotype-specific pneumococcal antibody response, whereas we did not identify predictors of a protein-specific antibody response.

CONCLUSIONS

Antibody responses occurred more frequently to pneumococcal proteins than to polysaccharide, and protein antibodies persisted for longer than polysaccharide-specific antibodies. PcpA, PiaA, and PsaA were the most immunogenic proteins.

Bacterial Infections in Adult HIV-Infected Patients

PURPOSE

The purpose of this article is to critically review articles published from the pre-HAART era to the present on bacterial infections in adult HIV-infected patients.

METHOD

Literature search on bacterial infections in HIV-infected patients yields predominantly small case series from single centers, many of which are retrospectively collected.

RESULTS

Variations in case selection limit the utility of these articles for assessing the epidemiology and clinical features of a particular infection. Nonetheless, numerous articles indicate that certain bacterial infections occur most often when CD4 cell counts are < 200/mm3. In the pre-HAART era, others suggest that PcP prophylaxis with TMP/SMX and MAC prophylaxis with macrolides reduced rates of several bacterial infections. Since the advent of HAART, however, some articles suggest that the incidence of various infections has declined and that withdrawal of OI prophylaxis in patients who have had HAART restoration of CD4 cell counts has not led to an increase in certain bacterial infections.

CONCLUSION

This review suggests that bacterial infections may have declined in the HAART era, as multicenter cohort studies have shown to be the case with AIDS-associated OIs. Nonetheless, preventive measures such as pneumococcal vaccination and smoking cessation remain effective strategies.

Response to Pneumococcal Polysaccharide Vaccination in HIV-Positive Individuals on Long Term Highly Active Antiretroviral Therapy

Background and objectives

Streptococcus pneumoniae continues to cause serious infections in HIV-positive individuals in the era of highly active anti-retroviral therapy. This led to the recommendation to revaccinate HIV-positive individuals with PPV23 five years after primary vaccination. The benefits of revaccination and the impact of long term highly active anti-retroviral therapy (HAART) on antigen-specific B cell reconstitution have remained unclear thus far and were investigated.

Design and methods

We assessed antibody levels, opsonophagocytic activity and phenotype of pneumococcal polysaccharide (PPS) specific-B cells post-revaccination in long term HAART cohorts stratified according to CD4 count as group A (CD4>200) and group B (CD4<200). Anti-PPS IgG, IgM and functional antibody response against vaccine serotypes 14 and 23F were measured by ELISA and opsonophagocytic assay followed by phenotypic analysis of PPS14 and 23F-specific B cells using fluorescently labeled PPS.

Results

Significant increases in total and functional antibody titers were noted in groups A and B post-vaccination concomitant with significant rise in PPS-specific IgM memory B cells, a critical B cell subset required for protection against PPS although the overall response remained significantly diminished compared to HIV-negative volunteers.

Conclusion

Comparable increases in opsonophagocytic titers between study groups A and B concomitant with a comparable rise in PPS-specific IgM memory B cells indicate revaccination to be beneficial regardless of the degree of CD4 T cell reconstitution. These findings emphasize the importance of defining effective vaccination practices amongst high-risk individuals.

Healthy HIV-1-infected individuals on highly active antiretroviral therapy harbor HIV-1 in their alveolar macrophages

In a prospective cross-sectional study we quantified HIV viral load within the alveolar macrophage in a cohort of healthy HIV-infected subjects who did not have medical comorbidities or smoke cigarettes to determine if alveolar macrophage proviral DNA was associated with alveolar macrophage phagocytic immune dysfunction. We enrolled 23 subjects who underwent bronchoscopy and bronchoalveolar lavage. Alveolar macrophages were isolated and HIV-1 RNA was quantified in the cells using the Abbott RealTime HIV-1 Assay. Proviral DNA was qualitatively measured using a modified version of the HIV-1 RNA assay. Phagocytosis measured by incubating alveolar macrophages with FITC-labeled Staphylococcus aureus and determining fluorescence with a Zeiss inverted microscope. Phagocytic index was calculated as (% positive cells × mean channel fluorescence)/100. Sixteen subjects had (+) proviral DNA and seven had (-) proviral DNA in their alveolar macrophages. Of all subjects 100% in both groups were on highly active antiretroviral therapy (HAART). The median plasma viral load was 0 in both groups. HIV-1-infected subjects with (+) proviral DNA in their alveolar macrophages had a significantly lower median alveolar macrophage phagocytic index compared to those with (-) proviral DNA in their alveolar macrophages [11.8 (IQR 4.8-39.0) vs. 64.9 (IQR 14.0-166.0), p = 0.05]. Alveolar macrophages harbor HIV even in otherwise healthy subjects with undetectable plasma viral loads, representing a potential reservoir for the virus. In addition, HIV viral replication within the macrophage may impair phagocytosis and other immune functions in the lung, leading to an increased risk for lung infection.

The effect of HIV infection on the host response to bacterial sepsis

Bacterial sepsis is an important cause of morbidity and mortality in patients with HIV. HIV causes increased susceptibility to invasive infections and affects sepsis pathogenesis caused by pre-existing activation and exhaustion of the immune system. We review the effect of HIV on different components of immune responses implicated in bacterial sepsis, and possible mechanisms underlying the increased risk of invasive bacterial infections. We focus on pattern recognition receptors and innate cellular responses, cytokines, lymphocytes, coagulation, and the complement system. A combination of factors causes increased susceptibility to infection and can contribute to a disturbed immune response during a septic event in patients with HIV. HIV-induced perturbations of the immune system depend on stage of infection and are only in part restored by combination antiretroviral therapy. Immunomodulatory treatments currently under development for sepsis might be particularly beneficial to patients with HIV co-infection because many pathogenic mechanisms in HIV and sepsis overlap.

Incidence and risk factors for invasive pneumococcal disease in HIV-infected and non-HIV-infected individuals before and after the introduction of combination antiretroviral therapy: persistent high risk among HIV-infected injecting drug users

BACKGROUND

Invasive pneumococcal disease (IPD) is an important cause of morbidity among individuals infected with human immunodeficiency virus (HIV). We described incidence and risk factors for IPD in HIV-infected and uninfected individuals.

METHODS

Nationwide population-based cohort study of HIV-infected adults treated at all Danish HIV treatment centers during 1995-2012. Nineteen population-matched controls per HIV-infected individual were retrieved. The risk of IPD was assessed using Poisson regression.

RESULTS

The incidence of IPD was 304.7 cases per 100 000 person-years of follow-up (PYFU) in HIV-infected and 12.8 per 100 000 PYFU in HIV-uninfected individuals. After adjusting for confounders, HIV infection (relative risk [RR], 24.4 [95% confidence interval [CI], 23.7-25.1]), male sex (RR, 1.20 [95% CI, 1.16-1.24]), increasing age (per year) (RR, 1.03 [95% CI, 1.03-1.04]), and calendar period (pre-cART RR, 2.80 [95% CI, 2.70-2.91] compared with late cART) were significantly associated with an increased risk of IPD. Among HIV-infected individuals, male sex (RR, 1.57 [95% CI, 1.49-1.66]), smoking (RR, 1.34 [95% CI, 1.26-1.42]), and injecting drug use (RR, 2.51 [95% CI, 2.26-2.67]) were associated with an increased risk of IPD. Detectable viral loads (RR, 1.88 [95% CI, 1.79-1.98]) and a relative fall in CD4 T-cell counts were also associated with an increased risk (≥500 to 350-500 CD4 T cells/µL: RR, 1.29 [95% CI, 1.21-1.37] and <100 cells/µL: RR, 7.4 [95% CI, 6.87-8.02]). The risk of IPD declined over time, although this was not the case for IDUs where the risk remained unchanged.

CONCLUSIONS

The incidence of IPD in HIV-infected individuals remained significantly higher than the incidence observed in non-HIV-infected subjects, despite the widespread use of cART. IDUs have a persistently high risk of IPD. Injecting drug use, smoking, and the receipt of cART are suitable targets for preventive measures in the future.

Vaccination coverage against hepatitis A and B viruses, Streptococcus pneumoniae, seasonal flu, and A(H1N1)2009 pandemic influenza in HIV-infected patients

BACKGROUND

Several vaccines are recommended in HIV-infected patients due to an increased risk of vaccine-preventable infections, severe forms of the disease, or shared transmission routes. Few data are available regarding vaccination coverage and its determinants in this population.

METHODS

A cross-sectional study was performed in HIV-infected patients included in a hospital-based cohort in 2011. Vaccination coverage against hepatitis A virus (HAV), hepatitis B virus (HBV), seasonal and A(H1N1)2009 pandemic influenza, and invasive pneumococcal diseases (IPD) were recorded. Factors associated with vaccination were assessed by multivariate logistic regression.

RESULTS

2467 patients were included (median age: 47 years; male gender 71.5%; men having sex with men (MSM): 43.9%; CDC stage C: 24.3%; HBV and/or hepatitis C virus co-infection: 14.4%). Median duration of HIV infection was 10 years and 93.1% of patients received combination antiretroviral therapy. At baseline, the median CD4 count was 527 cells/mm(3) and HIV viral load was <50 copies/mL in 83.3% of cases. Vaccination coverage for HBV, HAV, seasonal influenza, A(H1N1)2009 pandemic influenza, and IPD were 61.9%, 47.4%, 30.9, 48.3%, and 64.6%, respectively. Factors independently associated with vaccination were a younger (HBV) or an older age (influenza), male gender (HBV, HAV), MSM (HBV), CD4 count >200/mm(3) and HIV-RNA <50 copies/mL (IPD, influenza), longer duration of HIV infection (IPD, influenza), and follow-up by an experienced physician (HBV, IPD).

CONCLUSIONS

Vaccination coverage remained insufficient for all vaccine-preventable infections investigated in this study. Determinants for vaccination were largely not evidence-based, and efforts should be focused on improving physicians' knowledge about guidelines.

A review of the evidence to inform pneumococcal vaccine recommendations for risk groups aged 2 years and older

For decades, vaccination with the 23-valent polysaccharide pneumococcal vaccine (PPV23) has been available for risk groups aged ⩾2 years to prevent invasive pneumococcal disease (IPD). Recently, a 13-valent pneumococcal conjugated vaccine (PCV13) has been licensed for use in all age groups. PCV13 may induce better protection than PPV23 because of different immunogenic properties. This called for a revision of vaccine recommendations for risk groups. We therefore reviewed literature on risk groups for IPD, and effectiveness and safety of pneumococcal vaccines and supplemented that with information from public health institutes, expert consultations and data on IPD epidemiology. We included 187 articles. We discuss the implications of the heterogenic vulnerability for IPD within and between risk groups, large indirect effects of childhood immunization, and limited knowledge on additional clinical benefits of PCV13 in combination with PPV23 for the Norwegian recommendations. These are now step-wise and consider the need for vaccination, choice of pneumococcal vaccines, and re-vaccination interval by risk group.

Metabolomics of bronchoalveolar lavage differentiate healthy HIV-1-infected subjects from controls

Despite antiretroviral therapy, pneumonias from pathogens such as pneumococcus continue to cause significant morbidity and mortality in HIV-1-infected individuals. Respiratory infections occur despite high CD4 counts and low viral loads; therefore, better understanding of lung immunity and infection predictors is necessary. We tested whether metabolomics, an integrated biosystems approach to molecular fingerprinting, could differentiate such individual characteristics. Bronchoalveolar lavage fluid (BALf ) was collected from otherwise healthy HIV-1-infected individuals and healthy controls. A liquid chromatography-high-resolution mass spectrometry method was used to detect metabolites in BALf. Statistical and bioinformatic analyses used false discovery rate (FDR) and orthogonally corrected partial least-squares discriminant analysis (OPLS-DA) to identify groupwise discriminatory factors as the top 5% of metabolites contributing to 95% separation of HIV-1 and control. We enrolled 24 subjects with HIV-1 (median CD4=432) and 24 controls. A total of 115 accurate mass m/z features from C18 and AE analysis were significantly different between HIV-1 subjects and controls (FDR=0.05). Hierarchical cluster analysis revealed clusters of metabolites, which discriminated the samples according to HIV-1 status (FDR=0.05). Several of these did not match any metabolites in metabolomics databases; mass-to-charge 325.065 ([M+H](+)) was significantly higher (FDR=0.05) in the BAL of HIV-1-infected subjects and matched pyochelin, a siderophore-produced Pseudomonas aeruginosa. Metabolic profiles in BALf differentiated healthy HIV-1-infected subjects and controls. The lack of association with known human metabolites and inclusion of a match to a bacterial metabolite suggest that the differences could reflect the host's lung microbiome and/or be related to subclinical infection in HIV-1-infected patients.