HIV post-treatment controllers have distinct immunological and virological features.

HIV post-treatment controllers (PTCs) are rare individuals who maintain low levels of viremia after stopping antiretroviral therapy (ART). Understanding the mechanisms of HIV post-treatment control will inform development of strategies aiming at achieving HIV functional cure. In this study, we evaluated 22 PTCs from 8 AIDS Clinical Trials Group (ACTG) analytical treatment interruption (ATI) studies who maintained viral loads ≤400 copies/mL for ≥24 wk. There were no significant differences in demographics or frequency of protective and susceptible human leukocyte antigen (HLA) alleles between PTCs and post-treatment noncontrollers (NCs, n = 37). Unlike NCs, PTCs demonstrated a stable HIV reservoir measured by cell-associated RNA (CA-RNA) and intact proviral DNA assay (IPDA) during analytical treatment interruption (ATI). Immunologically, PTCs demonstrated significantly lower CD4+ and CD8+ T cell activation, lower CD4+ T cell exhaustion, and more robust Gag-specific CD4+ T cell responses and natural killer (NK) cell responses. Sparse partial least squares discriminant analysis (sPLS-DA) identified a set of features enriched in PTCs, including a higher CD4+ T cell% and CD4+/CD8+ ratio, more functional NK cells, and a lower CD4+ T cell exhaustion level. These results provide insights into the key viral reservoir features and immunological profiles for HIV PTCs and have implications for future studies evaluating interventions to achieve an HIV functional cure.

Tocilizumab in Hospitalized Patients with Severe Covid-19 Pneumonia.

BACKGROUND: Coronavirus disease 2019 (Covid-19) is associated with immune dysregulation and hyperinflammation, including elevated interleukin-6 levels. The use of tocilizumab, a monoclonal antibody against the interleukin-6 receptor, has resulted in better outcomes in patients with severe Covid-19 pneumonia in case reports and retrospective observational cohort studies. Data are needed from randomized, placebo-controlled trials. METHODS: In this phase 3 trial, we randomly assigned patients who were hospitalized with severe Covid-19 pneumonia in a 2:1 ratio receive a single intravenous infusion of tocilizumab (at a dose of 8 mg per kilogram of body weight) or placebo. Approximately one quarter of the participants received a second dose of tocilizumab or placebo 8 to 24 hours after the first dose. The primary outcome was clinical status at day 28 on an ordinal scale ranging from 1 (discharged or ready for discharge) to 7 (death) in the modified intention-to-treat population, which included all the patients who had received at least one dose of tocilizumab or placebo. RESULTS: Of the 452 patients who underwent randomization, 438 (294 in the tocilizumab group and 144 in the placebo group) were included in the primary and secondary analyses. The median value for clinical status on the ordinal scale at day 28 was 1.0 (95% confidence interval [CI], 1.0 to 1.0) in the tocilizumab group and 2.0 (non-ICU hospitalization without supplemental oxygen) (95% CI, 1.0 to 4.0) in the placebo group (between-group difference, -1.0; 95% CI, -2.5 to 0; P = 0.31 by the van Elteren test). In the safety population, serious adverse events occurred in 103 of 295 patients (34.9%) in the tocilizumab group and in 55 of 143 patients (38.5%) in the placebo group. Mortality at day 28 was 19.7% in the tocilizumab group and 19.4% in the placebo group (weighted difference, 0.3 percentage points; 95% CI, -7.6 to 8.2; nominal P = 0.94). CONCLUSIONS: In this randomized trial involving hospitalized patients with severe Covid-19 pneumonia, the use of tocilizumab did not result in significantly better clinical status or lower mortality than placebo at 28 days. (Funded by F. Hoffmann-La Roche and the Department of Health and Human Services; COVACTA ClinicalTrials.gov number, NCT04320615.).

Transcriptomic Signatures of Human Immunodeficiency Virus Post-Treatment Control.

Posttreatment controllers (PTCs) are rare HIV-infected individuals who can limit viral rebound after antiretroviral therapy interruption (ATI), but the mechanisms of this remain unclear. To investigate these mechanisms, we quantified various HIV RNA transcripts (via reverse transcription droplet digital PCR [RT-ddPCR]) and cellular transcriptomes (via RNA-seq) in blood cells from PTCs and noncontrollers (NCs) before and two time points after ATI. HIV transcription initiation did not significantly increase after ATI in PTCs or in NCs, whereas completed HIV transcripts increased at early ATI in both groups and multiply-spliced HIV transcripts increased only in NCs. Compared to NCs, PTCs showed lower levels of HIV DNA, more cell-associated HIV transcripts per total RNA at all times, no increase in multiply-spliced HIV RNA at early or late ATI, and a reduction in the ratio of completed/elongated HIV RNA after early ATI. NCs expressed higher levels of the IL-7 pathway before ATI and expressed higher levels of multiple cytokine, inflammation, HIV transcription, and cell death pathways after ATI. Compared to the baseline, the NCs upregulated interferon and cytokine (especially TNF) pathways during early and late ATI, whereas PTCs upregulated interferon and p53 pathways only at early ATI and downregulated gene translation during early and late ATI. In NCs, viral rebound after ATI is associated with increases in HIV transcriptional completion and splicing, rather than initiation. Differences in HIV and cellular transcription may contribute to posttreatment control, including an early limitation of spliced HIV RNA, a delayed reduction in completed HIV transcripts, and the differential expression of the IL-7, p53, and TNF pathways. IMPORTANCE The findings presented here provide new insights into how HIV and cellular gene expression change after stopping ART in both noncontrollers and posttreatment controllers. Posttreatment control is associated with an early ability to limit increases in multiply-spliced HIV RNA, a delayed (and presumably immune-mediated) ability to reverse an initial rise in processive/completed HIV transcripts, and multiple differences in cellular gene expression pathways. These differences may represent correlates or mechanisms of posttreatment control and may provide insight into the development and/or monitoring of therapeutic strategies that are aimed at a functional HIV cure.

Myocardial Steatosis Among Antiretroviral Therapy-Treated People With Human Immunodeficiency Virus Participating in the REPRIEVE Trial.

BACKGROUND: People with human immunodeficiency virus (PWH) face increased risks for heart failure and adverse heart failure outcomes. Myocardial steatosis predisposes to diastolic dysfunction, a heart failure precursor. We aimed to characterize myocardial steatosis and associated potential risk factors among a subset of the Randomized Trial to Prevent Vascular Events in HIV (REPRIEVE) participants. METHODS: Eighty-two PWH without known heart failure successfully underwent cardiovascular magnetic resonance spectroscopy, yielding data on intramyocardial triglyceride (IMTG) content (a continuous marker for myocardial steatosis extent). Logistic regression models were applied to investigate associations between select clinical characteristics and odds of increased or markedly increased IMTG content. RESULTS: Median (Q1, Q3) IMTG content was 0.59% (0.28%, 1.15%). IMTG content was increased (> 0.5%) among 52% and markedly increased (> 1.5%) among 22% of participants. Parameters associated with increased IMTG content included age (P = .013), body mass index (BMI) ≥ 25 kg/m2 (P = .055), history of intravenous drug use (IVDU) (P = .033), and nadir CD4 count < 350 cells/mm³ (P = .055). Age and BMI ≥ 25 kg/m2 were additionally associated with increased odds of markedly increased IMTG content (P = .049 and P = .046, respectively). CONCLUSIONS: A substantial proportion of antiretroviral therapy-treated PWH exhibited myocardial steatosis. Age, BMI ≥ 25 kg/m2, low nadir CD4 count, and history of IVDU emerged as possible risk factors for myocardial steatosis in this group. CLINICAL TRIALS REGISTRATION: NCT02344290; NCT03238755.

Possible Prognostic Value of Serial Brain MRIs in Powassan Virus Encephalitis.

Powassan virus (POWV) encephalitis is a rare tickborne illness. We describe the clinical course, laboratory findings, and imaging for a patient with POWV in Massachusetts, USA. Clinical presentation and laboratory findings were nonspecific. Improvement on brain magnetic resonance imaging after 2 weeks preceded clinical improvement by months, suggesting possible prognostic value.

Effect of Short-Term Antiretroviral Therapy Interruption on Levels of Integrated HIV DNA.

Analytic treatment interruption (ATI) studies are required to evaluate strategies aimed at achieving ART-free HIV remission, but the impact of ATI on the viral reservoir remains unclear. We validated a DNA size selection-based assay for measuring levels of integrated HIV DNA and applied it to assess the effects of short-term ATI on the HIV reservoir. Samples from participants from four AIDS Clinical Trials Group ATI studies were assayed for integrated HIV DNA levels. Cryopreserved peripheral blood mononuclear cells (PBMCs) were obtained for 12 participants with available samples pre-ATI and approximately 6 months after ART resumption. Four participants also had samples available during the ATI. The median duration of ATI was 12 weeks. Validation of the HIV integrated DNA size-exclusion (HIDE) assay was performed using samples spiked with unintegrated HIV DNA, HIV-infected cell lines, and participant PBMCs. The HIDE assay eliminated 99% of unintegrated HIV DNA species and strongly correlated with the established Alu-gag assay. For the majority of individuals, integrated DNA levels increased during ATI and subsequently declined upon ART resumption. There was no significant difference in the levels of integrated HIV DNA between the pre- and post-ATI time points, with a median ratio of post- to pre-ATI HIV DNA levels of 0.95. Using a new integrated HIV DNA assay, we found minimal change in the levels of integrated HIV DNA in participants who underwent an ATI, followed by 6 months of ART. This suggests that short-term ATI can be conducted without a significant impact on the levels of integrated proviral DNA in the peripheral blood.IMPORTANCE Interventions aimed at achieving sustained antiretroviral therapy (ART)-free HIV remission require treatment interruption trials to assess their efficacy. However, these trials are accompanied by safety concerns related to the expansion of the viral reservoir. We validated an assay that uses an automated DNA size-selection platform for quantifying levels of integrated HIV DNA and is less sample- and labor-intensive than current assays. Using stored samples from AIDS Clinical Trials Group studies, we found that short-term ART discontinuation had minimal impact on integrated HIV DNA levels after ART resumption, providing reassurance about the reservoir effects of short-term treatment interruption trials.

The Control of HIV After Antiretroviral Medication Pause (CHAMP) Study: Posttreatment Controllers Identified From 14 Clinical Studies.

Background: HIV posttreatment controllers are rare individuals who start antiretroviral therapy (ART), but maintain HIV suppression after treatment interruption. The frequency of posttreatment control and posttreatment interruption viral dynamics have not been well characterized. Methods: Posttreatment controllers were identified from 14 studies and defined as individuals who underwent treatment interruption with viral loads ≤400 copies/mL at two-thirds or more of time points for ≥24 weeks. Viral load and CD4+ cell dynamics were compared between posttreatment controllers and noncontrollers. Results: Of the 67 posttreatment controllers identified, 38 initiated ART during early HIV infection. Posttreatment controllers were more frequently identified in those treated during early versus chronic infection (13% vs 4%, P < .001). In posttreatment controllers with weekly viral load monitoring, 45% had a peak posttreatment interruption viral load of ≥1000 copies/mL and 33% had a peak viral load ≥10000 copies/mL. Of posttreatment controllers, 55% maintained HIV control for 2 years, with approximately 20% maintaining control for ≥5 years. Conclusions: Posttreatment control was more commonly identified amongst early treated individuals, frequently characterized by early transient viral rebound and heterogeneous durability of HIV remission. These results may provide mechanistic insights and have implications for the design of trials aimed at achieving HIV remission.

Association Between Initial Route of Fluoroquinolone Administration and Outcomes in Patients Hospitalized for Community-acquired Pneumonia.

BACKGROUND: Fluoroquinolones have equivalent oral and intravenous bioavailability, but hospitalized patients with community-acquired pneumonia (CAP) generally are treated intravenously. Our objectives were to compare outcomes of hospitalized CAP patients initially receiving intravenous vs oral respiratory fluoroquinolones. METHODS: This was a retrospective cohort study utilizing data from 340 hospitals involving CAP patients admitted to a non-intensive care unit (ICU) setting from 2007 to 2010, who received intravenous or oral levofloxacin or moxifloxacin. The primary outcome was in-hospital mortality. Secondary outcomes included clinical deterioration (transfer to ICU, initiation of vasopressors, or invasive mechanical ventilation [IMV] initiated after the second hospital day), antibiotic escalation, length of stay (LOS), and cost. RESULTS: Of 36 405 patients who met inclusion criteria, 34 200 (94%) initially received intravenous treatment and 2205 (6%) received oral treatment. Patients who received oral fluoroquinolones had lower unadjusted mortality (1.4% vs 2.5%; P = .002), and shorter mean LOS (5.0 vs 5.3; P < .001). Multivariable models using stabilized inverse propensity treatment weighting revealed lower rates of antibiotic escalation for oral vs intravenous therapy (odds ratio [OR], 0.84; 95% confidence interval [CI], .74-.96) but no differences in hospital mortality (OR, 0.82; 95% CI, .58-1.15), LOS (difference in days 0.03; 95% CI, -.09-.15), cost (difference in $-7.7; 95% CI, -197.4-182.0), late ICU admission (OR, 1.04; 95% CI, .80-1.36), late IMV (OR, 1.17; 95% CI, .87-1.56), or late vasopressor use (OR, 0.94; 95% CI, .68-1.30). CONCLUSIONS: Among hospitalized patients who received fluoroquinolones for CAP, there was no association between initial route of administration and outcomes. More patients may be treated orally without worsening outcomes.

Immunogenicity and Safety of 13-Valent Pneumococcal Conjugate Vaccine in HIV-Infected Adults Previously Vaccinated With Pneumococcal Polysaccharide Vaccine.

BACKGROUND: Persons with human immunodeficiency virus (HIV) infection are at increased risk of pneumococcal disease. We evaluated the safety and immunogenicity of 13-valent pneumococcal conjugate vaccine (PCV13) in this population. METHODS: HIV-infected persons ≥ 18 years of age who were previously vaccinated with ≥ 1 dose of 23-valent pneumococcal polysaccharide vaccine (PPSV23) and had CD4 cell counts ≥ 200 cells/mm(3) and HIV viral loads <50 000 copies/mL were enrolled in this 3-dose PCV13 open-label study. RESULTS: A total of 329 subjects received ≥ 1 dose, and 279 received 3 doses administered at 6-month intervals. Increases in anticapsular polysaccharide immunoglobulin G concentrations and opsonophagocytic antibody titers were demonstrated 1 month after each of the 3 doses of PCV13. Antibody levels were generally similar after each dose. The responses were similar whether subjects had previously received 1 or ≥ 2 doses of PPSV23. Pain at the injection-site was the most common local reaction. Severe injection site or systemic events were uncommon. CONCLUSIONS: Vaccination with PCV13 induces anticapsular immunoglobulin G and opsonophagocytic antibody responses in HIV-infected adults with prior PPSV23 vaccination and CD4 cell counts ≥ 200 cells/mm(3). The observations support the use of PCV13 in this population. CLINICAL TRIALS REGISTRATION: NCT00963235.

Association of guideline-based antimicrobial therapy and outcomes in healthcare-associated pneumonia.

OBJECTIVES: Guidelines for treatment of healthcare-associated pneumonia (HCAP) recommend empirical therapy with broad-spectrum antimicrobials. Our objective was to examine the association between guideline-based therapy (GBT) and outcomes for patients with HCAP. PATIENTS AND METHODS: We conducted a pharmacoepidemiological cohort study at 346 US hospitals. We included adults hospitalized between July 2007 and June 2010 for HCAP, defined as patients admitted from a nursing home, with end-stage renal disease or immunosuppression, or discharged from a hospital in the previous 90 days. Outcome measures included in-hospital mortality, length of stay and costs. RESULTS: Of 85 097 patients at 346 hospitals, 31 949 (37.5%) received GBT (one agent against MRSA and at least one against Pseudomonas). Compared with patients who received non-GBT, those who received GBT had a heavier burden of chronic disease and more severe pneumonia. GBT was associated with higher mortality (17.1% versus 7.7%, P < 0.001). Adjustment for demographics, comorbidities, propensity for treatment with GBT and initial severity of disease decreased, but did not eliminate, the association (OR 1.39, 95% CI 1.32-1.47). Using an adaptation of an instrumental variable analysis, GBT was not associated with higher mortality (OR 0.93, 95% CI 0.75-1.16). Adjusted length of stay and costs were also higher with GBT. CONCLUSIONS: Among patients who met HCAP criteria, GBT was not associated with lower adjusted mortality, length of stay or costs in any analyses. Better criteria are needed to identify patients at risk for MDR infections who might benefit from broad-spectrum antimicrobial coverage.

Successful kidney transplantation from a hepatitis B surface antigen-positive donor to an antigen-negative recipient using a novel vaccination regimen.

Transplanting a kidney from a hepatitis B surface antigen (HBsAg)-positive donor to an HBsAg-negative recipient who is naturally immune has been successful in countries endemic for hepatitis B virus (HBV). However, in most of these cases, the donors were deceased. We present a report of a successful HBsAg-discordant kidney transplantation in the United States; in this case, a living donor kidney was transplanted to a vaccinated recipient. The wife of a 58-year-old HBsAg-negative man volunteered to donate a kidney to her husband. She had chronic hepatitis B but undetectable HBV DNA. She tested positive for HBsAg and antibody to hepatitis B core antigen, but hepatitis B e antigen was undetectable. The recipient failed to develop an antibody response to 3 doses of intramuscular recombinant HBV vaccine given in consecutive months. Immunity was induced by using biweekly intradermal vaccine. However, antibody titer tapered to <10 mIU/mL over 14 months. An intramuscular booster vaccine resulted in a prolonged anamnestic response, allowing for successful living unrelated donor transplantation. During the 10 years since transplantation, the patient has continued to have normal liver function, with undetectable HBsAg and HBV DNA. Antibody titers to HBsAg slowly decreased to 5.8 mIU/mL during the 10 years. Transplant function has been well preserved. This approach to inducing long-term immunity for transplantation merits further study in the United States.

Factors Associated With Fecal Microbiota Transplant Failure in the Treatment of Recurrent Clostridioides difficile Infection: A Single-Center Retrospective Study.

Background Clostridioides difficile infection (CDI) is a major cause of hospital-acquired diarrhea and is associated with substantial morbidity and mortality. Recurrences following treatment are common. Fecal microbiota transplantation (FMT) is a therapeutic intervention in which stool from a healthy donor is administered to a patient with recurrent CDI. Studies to date of predictors of FMT failure have primarily included inpatients. In this study, we aimed to describe FMT failure rates within one year of FMT and evaluate factors associated with FMT failure. Methodology We conducted an exploratory retrospective study of consecutive patients who underwent outpatient FMT at a single tertiary care center in Western Massachusetts from December 2014 through September 2018. We collected patient data including demographics, CDI-related factors, and FMT-related factors. FMT failure was defined as non-response or recurrence of diarrhea, associated with positive stool C. difficile toxin or polymerase chain reaction. Unadjusted relative risk (RR) and 95% confidence intervals for factors associated with FMT failure were estimated using log-binomial regression. Results A total of 92 patients were included with a mean age of 64 years. CDI severity was mild or moderate in 73% and severe or fulminant in 27%. The most common FMT indication was recurrent CDI in 76% of patients. FMT failure occurred in 25 of 92 (27%) patients, with half occurring within 11 days. Factors associated with FMT failure were active malignancy (RR = 2.56), prior hospitalizations (RR = 2.42), and receipt of non-CDI antibiotics within six months of FMT (RR = 2.80). We did not observe strong associations for risk of FMT failure with age ≥65, sex, use of proton pump inhibitors or H2 receptor agonists, history of colectomy, immunosuppression, history of malignancy, diabetes, appendectomy, CDI severity, or probiotic use. Conclusions Active malignancy, prior CDI hospitalizations, and non-CDI antibiotics within six months before FMT were associated with FMT failure in the outpatient setting. Knowledge of the above factors may help inform shared decision-making with patients at risk for FMT failure.

Genome sequence of Listeria monocytogenes 07PF0776, a cardiotropic serovar 4b strain.

Listeria monocytogenes is a food-borne bacterial pathogen commonly associated with serious invasive infections of the central nervous system or of the developing fetus. We present the genome sequence of Listeria monocytogenes 07PF0776, a serovar 4b isolate from a human myocardial abscess that exhibits enhanced invasion of cardiac tissue.

Tocilizumab in patients hospitalised with COVID-19 pneumonia: Efficacy, safety, viral clearance, and antibody response from a randomised controlled trial (COVACTA).

Background: In COVACTA, a randomised, placebo-controlled trial in patients hospitalised with coronavirus disease-19 (COVID-19), tocilizumab did not improve 28-day mortality, but shortened hospital and intensive care unit stay. Longer-term effects of tocilizumab in patients with COVID-19 are unknown. Therefore, the efficacy and safety of tocilizumab in COVID-19 beyond day 28 and its impact on Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) clearance and antibody response in COVACTA were investigated. Methods: Adults in Europe and North America hospitalised with COVID-19 (N = 452) between April 3, 2020 and May 28, 2020 were randomly assigned (2:1) to double-blind intravenous tocilizumab or placebo and assessed for efficacy and safety through day 60. Assessments included mortality, time to hospital discharge, SARS-CoV-2 viral load in nasopharyngeal swab and serum samples, and neutralising anti-SARS-CoV-2 antibodies in serum. ClinicalTrials.gov registration: NCT04320615. Findings: By day 60, 24·5% (72/294) of patients in the tocilizumab arm and 25·0% (36/144) in the placebo arm died (weighted difference -0·5% [95% CI -9·1 to 8·0]), and 67·0% (197/294) in the tocilizumab arm and 63·9% (92/144) in the placebo arm were discharged from the hospital. Serious infections occurred in 24·1% (71/295) of patients in the tocilizumab arm and 29·4% (42/143) in the placebo arm. Median time to negative reverse transcriptase-quantitative polymerase chain reaction result in nasopharyngeal/oropharyngeal samples was 15·0 days (95% CI 14·0 to 21·0) in the tocilizumab arm and 21·0 days (95% CI 14·0 to 28·0) in the placebo arm. All tested patients had positive test results for neutralising anti-SARS-CoV-2 antibodies at day 60. Interpretation: There was no mortality benefit with tocilizumab through day 60. Tocilizumab did not impair viral clearance or host immune response, and no new safety signals were observed. Future investigations may explore potential biomarkers to optimize patient selection for tocilizumab treatment and combination therapy with other treatments. Funding: F. Hoffmann-La Roche Ltd and the US Department of Health and Human Services, Office of the Assistant Secretary for Preparedness and Response, Biomedical Advanced Research and Development Authority, under OT number HHSO100201800036C.

Similar efficacy of raltegravir when used with or without a protease inhibitor in treatment-experienced patients.

BACKGROUND: Patients with multiclass-resistant HIV-1 have limited treatment options. Raltegravir, an inhibitor of integrase, has shown excellent efficacy when used with protease inhibitors (Pis) in patients with drug-resistant HIV-1. Limited data are available however about the outcomes when using raltegravir without Pis in this population. METHODS: Medical records of subjects who received raltegravir as part of the Merck EAP study 0518 were reviewed and abstracted at participating sites. Eligibility criteria included HIV positivity, age ≥ 16 years, limited or no treatment options due to resistance or intolerance to multiple antiretroviral regimens, detectable viremia on current treatment regimen, and documented resistance to at least one drug in each antiretroviral class (PI, NNRTI, and nucleoside analogue). Demographic, clinical, and laboratory data were collected locally using a standardized collection form. Genotypic susceptibility scores (GSS) were determined from the most recent genotypic resistance test available prior to the initiation of raltegravir. The main objective was to compare virologic results in patients who received raltegravir with a PI versus those who received raltegravir without a PI. RESULTS: Four hundred forty-two subjects were evaluated from the respective sites in the EAP trial, of whom 340 were evaluable. The baseline mean HIV RNA was 4.6 log copies/ mL, and the mean CD4 cell count was 159 cells/µL. The median number of total and new antiretroviral agents in the background regimen was 4 and 2, respectively. Among the 254 patients who received a PI, the most common PI used was darunavir (89%). Etravirine was commonly used in both groups: 39% of the PI group and 67% of the non-PI group. At week 12, 67% of PI patients and 64% of non-PI patients achieved HIV RNA <75 copies/mL and 85% and 86%, respectively, achieved HIV RNA <400 copies/mL GSS, which was similar in both groups at baseline, predicted achieving an HIV RNA of <400 and 75 copies/mL at week 12 (P < .05). CONCLUSIONS: In treatment-experienced patients, the combination of raltegravir with a regimen not containing a PI (used with etravirine in two-thirds of patients) had similar virologic activity when compared to more standard regimens using raltegravir with a PI. The main determinant of efficacy was the number of active drugs as measured by GSS. These data expand the potential utility of raltegravir in patients with multidrug-resistant HIV.

Frequency of post treatment control varies by antiretroviral therapy restart and viral load criteria.

Clinical trials including an analytical treatment interruption (ATI) are vital for evaluating the efficacy of novel strategies for HIV remissions. We briefly describe an interactive tool for predicting viral rebound timing in ATI trials and the impact of posttreatment controller (PTC) definitions on PTC frequency estimates. A 4-week viral load threshold of 1000 cps/ml provides both high specificity and sensitivity for PTC detection. PTC frequency varies greatly based on the definition of a PTC.

Low prevalence of primary HIV resistance in western Massachusetts.

Most studies of primary antiretroviral (ARV) resistance have been conducted in large metropolitan areas with reported rates of 8% to 25%. We collected data on 99 HIV-1-infected antiretroviral-naive patients from several sites in Springfield, MA, who underwent genotypic resistance assay between 2004 and 2008. Only major resistance mutations per International AIDS Society-USA (IAS-USA) drug resistance mutations list were considered. The prevalence of resistance was 5% (5 of 99). Three patients had one nonnucleoside reverse transcriptase inhibitor (NNRTI) mutation: 103N, 103N, and 190A, 1 patient had a protease inhibitor (PI) mutation: 90M; and 1 patient had 3-class resistance with NNRTI: 181C, 190A, PI: 90M, and nucleoside analogue reverse transcriptase inhibitor (NRTI): 41L, 210W. Mean time from HIV diagnosis to resistance testing was shorter in patients with resistance versus those without: 9 (range 0.3-42 months) versus 27 (range 0.1-418 months), P = .11. There was a trend to lower mean CD4 count in those with resistance, 170 versus 318 cells/mm(3), P = .06. No differences were noted in gender, age, HIV risk category, or HIV RNA level. The low prevalence of primary resistance may be explained by differences in demographic and risk factors or may reflect the time from infection to resistance testing. Our findings emphasize the importance of continued resistance surveillance.

Antibiotic therapy and treatment failure in patients hospitalized for acute exacerbations of chronic obstructive pulmonary disease.

CONTEXT: Guidelines recommend antibiotic therapy for acute exacerbations of chronic obstructive pulmonary disease (COPD), but the evidence is based on small, heterogeneous trials, few of which include hospitalized patients. OBJECTIVE: To compare the outcomes of patients treated with antibiotics in the first 2 hospital days with those treated later or not at all. DESIGN, SETTING, AND PATIENTS: Retrospective cohort of patients aged 40 years or older who were hospitalized from January 1, 2006, through December 31, 2007, for acute exacerbations of COPD at 413 acute care facilities throughout the United States. MAIN OUTCOME MEASURES: A composite measure of treatment failure, defined as the initiation of mechanical ventilation after the second hospital day, inpatient mortality, or readmission for acute exacerbations of COPD within 30 days of discharge; length of stay, and hospital costs. RESULTS: Of 84,621 patients, 79% received at least 2 consecutive days of antibiotic treatment. Treated patients were less likely than nontreated patients to receive mechanical ventilation after the second hospital day (1.07%; 95% confidence interval [CI], 1.06%-1.08% vs 1.80%; 95% CI, 1.78%-1.82%), had lower rates of inpatient mortality (1.04%; 95% CI, 1.03%-1.05% vs 1.59%; 95% CI, 1.57%-1.61%), and had lower rates of readmission for acute exacerbations of COPD (7.91%; 95% CI, 7.89%-7.94% vs 8.79%; 95% CI, 8.74%-8.83%). Patients treated with antibiotic agents had a higher rate of readmissions for Clostridium difficile (0.19%; 95% CI, 0.187%-0.193%) than those who were not treated (0.09%; 95% CI, 0.086%-0.094%). After multivariable adjustment, including the propensity for antibiotic treatment, the risk of treatment failure was lower in antibiotic-treated patients (odds ratio, 0.87; 95% CI, 0.82-0.92). A grouped treatment approach and hierarchical modeling to account for potential confounding of hospital effects yielded similar results. Analysis stratified by risk of treatment failure found similar magnitudes of benefit across all subgroups. CONCLUSION: Early antibiotic administration was associated with improved outcomes among patients hospitalized for acute exacerbations of COPD regardless of the risk of treatment failure.

Subacute onset of paralysis in a person with AIDS.

We report a case of subacute onset of paraparesis in a patient with AIDS. Empiric treatment for toxoplasmosis of the brain and the spinal cord resulted in resolution of the paraparesis. This case highlights the differential diagnosis of toxoplasmosis of the spinal cord and reviews its management in HIV-infected patients.

Detection of nonnucleoside reverse-transcriptase inhibitor-resistant HIV-1 after discontinuation of virologically suppressive antiretroviral therapy.

Using standard and ultrasensitive techniques, we detected nonnucleoside reverse-transcriptase inhibitor-associated resistance mutations in 11 (20%) of 54 subjects who discontinued virologically suppressive nonnucleoside reverse-transcriptase inhibitor-containing antiretroviral therapy. Resistance was detected in 45% and 14% of subjects with a baseline human immunodeficiency virus type 1 RNA level of 51-400 copies/mL and