Roger Bedimo

Osteoporotic fracture risk associated with cumulative exposure to tenofovir and other antiretroviral agents.

Background:Whereas tenofovir (TDF) exposure has been associated with decreased bone density, it remains unclear whether it is associated with increased risk of osteoporotic fractures. Methods:Patients with any osteoporotic fracture (defined as wrist, vertebral or hip fracture) occurring after HIV diagnosis were identified by International Classification of Diseases – 9th Revision (ICD-9) code in the Veterans Affairs’ Clinical Case Registry from 1988 to 2009. Osteoporotic fracture risk associated with cumulative exposure to TDF and other antiretrovirals was examined in univariate analysis and multivariate model 1 (MV1 – controlling for race, age, tobacco use, diabetes, body mass index, and hepatitis C status) and model 2 (MV2 – controlling for MV1 variables + concomitant antiretroviral exposures). Results:Among 56 660 patients evaluated, TDF exposure (total 46 062 person-years) was associated with an osteoporotic fracture hazard ratio of 1.080 [95% confidence interval (CI) 1.02–1.15, P < 0.001] in univariate analysis, 1.06 (0.99–1.12) in MV1 and 1.06 (0.99–1.14) in MV2. Among patients entering the cohort in the highly active antiretroviral therapy (HAART) era (n = 32 439), TDF exposure was associated with a yearly hazard ratio for osteoporotic fracture of 1.16 (95% CI 1.08–1.24, P < 0.001) in univariate model, 1.13 (1.05–1.21, P = 0.001) in MV1 and 1.12 (1.03–1.21, P = 0.011) in MV2. Boosted protease inhibitor exposure was associated with hazard ratio of 1.11 (1.05–1.18, P = 0.001) in univariate model, 1.08 (1.01–1.15, P = 0.026) in MV1 and 1.05 (0.97–1.13, P = 0.237) in MV2. Among protease inhibitors, lopinavir/ritonavir (LPV/RTV) had an osteoporotic fracture hazard ratio of 1.09 (CI 1.00–1.20, P = 0.051) in MV2. Conclusion:Cumulative exposure to TDF and, among protease inhibitors, LPV/RTV was independently predictive of increased risk of osteoporotic fracture in the HAART era.

A Multicenter, Double-Blind Trial of a High-Dose Caspofungin Treatment Regimen versus a Standard Caspofungin Treatment Regimen for Adult Patients with Invasive Candidiasis

BACKGROUND The standard caspofungin treatment regimen (50 mg/day after a 70-mg dose on day 1) is effective and well tolerated for the treatment of invasive candidiasis, but experience with higher doses of caspofungin is limited. We evaluated the safety and efficacy of caspofungin at 3 times the standard dosing regimen. METHODS Patients with proven invasive candidiasis were randomized to receive a standard or high-dose (150 mg/day) caspofungin treatment regimen. Safety was assessed in all patients as treated. Efficacy was assessed as a secondary objective in a full-analysis-set population. A favorable overall response was defined as symptom resolution and microbiological clearance at the end of caspofungin therapy. RESULTS A total of 204 patients were included in the safety analysis (104 received the standard regimen, and 100 received the high-dose regimen), and 197 were included in the efficacy analysis (102 and 95 in the standard and high-dose treatment groups, respectively). Patient demographic characteristics, neutropenia status (6.7% and 8.0% had neutropenia, respectively), and Acute Physiology and Chronic Health Evaluation II scores (mean, 16.5 and 17, respectively) were similar between treatment groups. Significant drug-related adverse events occurred in 1.9% of patients receiving the standard regimen and 3.0% of patients receiving the high-dose regimen (difference, 1.1%; 95% confidence interval, -4.1% to 6.8%). The most-common drug-related adverse events in the standard and high-dose treatment groups were phlebitis (3.8% and 2.0%, respectively), increased alkaline phosphatase level (6.9% and 2.0%, respectively), and increased aspartate transaminase level (4.0% and 2.0%, respectively). Overall, 71.6% of patients who received the standard regimen and 77.9% of patients who received the high-dose regimen had favorable overall responses (difference, 6.3%; 95% confidence interval, -5.9% to 18.4%; not statistically significant). Mortality at 8 weeks after therapy was similar between groups. CONCLUSIONS Both caspofungin dosing regimens were effective and well tolerated in patients with invasive candidiasis. No safety concerns were found for caspofungin at a dosage of 150 mg/day.

Incidence of Non-AIDS-Defining Malignancies in HIV-Infected Versus Noninfected Patients in the HAART Era: impact of Immunosuppression

Background:The incidence of non-AIDS-defining malignancies (non-ADMs) is reported as unchanged or increasing in the highly active antiretroviral therapy era. Whether incidence of non-ADM is significantly higher in HIV-infected than in HIV-uninfected patients remains unclear. Methods:Incidence rates of malignancies were calculated in a cohort of veterans in care for HIV-infected and age, race, and gender-matched uninfected patients from 1997 to 2004. For HIV-infected patients, CD4 counts closest to first observation date were compared between those with and without cancer. Results:Thirty three thousand four hundred twenty HIV-infected and 66,840 HIV-uninfected patients were followed for a median of 5.1 and 6.4 years. The incidence rate ratio of HIV infected to HIV uninfected was 1.6 (1260 vs. 841 per 100,000 person-years; 95% confidence interval: 1.5 to 1.7). Incidence rate ratio for individual cancers was highest for anal cancer (14.9; confidence interval: 10.1 to 22.1). Among HIV-infected patients, median CD4 counts were lower for those with non-ADM (249 vs. 270, P = 0.02), anal cancer (156 vs. 270; P < 0.001), and Hodgkin lymphoma (217 vs. 269; P = 0.03). Prostate cancer was associated with a higher CD4 count (311 vs. 266; P < 0.001). Conclusions:In the highly active antiretroviral therapy era, the incidence of non-ADMs is higher among HIV-infected than HIV-uninfected patients, adjusting for age, race, and gender. Some non-ADMs do not seem to be associated with significantly lower CD4 counts.

Escherichia coli Sequence Type 131 (ST131) Subclone H30 as an Emergent Multidrug-Resistant Pathogen Among US Veterans

BACKGROUND Escherichia coli sequence type 131 (ST131), typically fluoroquinolone-resistant (FQ-R) and/or extended-spectrum β-lactamase (ESBL)-producing, has emerged globally. We assessed its prevalence and characteristics among US veterans. METHODS In 2011, 595 de-identified E. coli clinical isolates were collected systematically within 3 resistance groups (FQ-susceptible [FQ-S], FQ-R, and ESBL-producing) from 24 nationally distributed Veterans Affairs Medical Centers (VAMCs). ST131 and its H30 subclone were detected by polymerase chain reaction and compared with other E. coli for molecular traits, source, and resistance profiles. RESULTS ST131 accounted for 78% (184/236) of FQ-R and 64.2% (79/123) of ESBL-producing isolates, but only 7.2% (17/236) of FQ-S isolates (P < .001). The H30 subclone accounted for ≥95% of FQ-R and ESBL-producing, but only 12.5% of FQ-S, ST131 isolates (P < .001). By back-calculation, 28% of VAMC E. coli isolates nationally represented ST131. Overall, ST131 varied minimally in prevalence by specimen type, inpatient/outpatient source, or locale; was the most prevalent ST, followed distantly by ST95 and ST12 (13% each); and accounted for ≥40% (β-lactams), >50% (trimethoprim-sulfamethoxazole , multidrug), or >70% (ciprofloxacin, gentamicin) of total antimicrobial resistance. FQ-R and ESBL-producing ST131 isolates had higher virulence scores than corresponding non-ST131 isolates. ST131 pulsotypes overlapped extensively among VAMCs. CONCLUSIONS Among US veterans, ST131, primarily its H30 subclone, accounts for most antimicrobial-resistant E. coli and is the dominant E. coli strain overall. Possible contributors include multidrug resistance, extensive virulence gene content, and ongoing transmission. Focused attention to ST131, especially its H30 subclone, could reduce infection-related morbidity, mortality, and costs among veterans.

Non-HACEK Gram-Negative Bacillus Endocarditis

Context Infective endocarditis due to non-HACEK organisms has been considered to be associated with injection drug use. Contribution Analysis of 2761 cases of patients with infective endocarditis from an international collaborative of 61 hospitals found that non-HACEK organisms account for fewer than 2% of the cases, and that most patients with non-HACEK endocarditis had infections associated with health care. Of patients with non-HACEK infections, 59% had implanted endovascular devices or prosthetic valves, but only 4% had injection drug use. More than one half of patients with non-HACEK infections required cardiac surgery and 24% died. Implication Infective endocarditis due to non-HACEK organisms is a rare but frequently fatal condition. It is much more frequently associated with implanted endovascular devices than with injection drug use. The Editors Infective endocarditis caused by non-HACEK (species other than Haemophilus species, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, or Kingella species) gram-negative bacilli is a rare and poorly characterized disease. The literature describing non-HACEK gram-negative bacillus endocarditis primarily consists of several small case series from the 1970s and 1980s of outbreaks in injection drug users in large urban areas, such as Detroit (1, 2), Cleveland (3), and San Francisco (4, 5). As a result, endocarditis due to non-HACEK gram-negative bacilli has been considered to be almost exclusively associated with injection drug use (6, 7). In contrast to this reporting bias, however, non-HACEK gram-negative bacillus endocarditis has been occasionally reported to be a nosocomial problem, particularly in patients with early endocarditis after cardiac surgery (811). The International Collaboration on Endocarditis Prospective Cohort Study (ICE-PCS) database was created in 1999. From 1 January 2000 to 31 August 2005, 2761 patients with definite endocarditis from 61 centers in 28 countries were prospectively enrolled. This resource offers a unique opportunity to evaluate the epidemiology, characteristics, and outcome of endocarditis due to non-HACEK gram-negative bacilli in a large, contemporary, and international cohort of well-characterized patients with endocarditis. Methods The International Collaboration on Endocarditis Prospective Cohort Study Hospitalized patients with endocarditis (12) were identified prospectively by using site-specific procedures to ensure consecutive enrollment. Informed consent (oral or written) was obtained from all patients according to local institutional review board or ethics committee instructions. A standard case report form containing 275 variables was completed for each patient on enrollment at the participating site. The ICE-PCS database is maintained at the Duke Clinical Research Institute, Durham, North Carolina, which serves as the coordinating center for the ICE studies, with approval from the institutional review board. We included all patients with endocarditis from sites that met performance criteria for participation. These site criteria included 1) minimum enrollment of 12 cases per year in a center with access to cardiac surgery, 2) the presence of patient identification procedures to ensure consecutive enrollment and to minimize ascertainment bias (as described elsewhere) (13, 14), 3) high-quality data with query resolution, and 4) institutional review board or ethics committee approval or waiver based on local standards. All patients from sites that did not meet these criteria (totaling 494 case-patients from 14 sites) were excluded. Sample We included patients who had both definite endocarditis according to the modified Duke criteria (12) and isolation of a pure culture of an aerobic gram-negative bacillus from the bloodstream or valve. To ensure that the diagnosis of gram-negative endocarditis was accurate, the following additional criteria were applied when interpreting the blood culture results: 1) the patients bacteremia had to meet the definition for persistently positive blood cultures when applying the modified Duke criteria; 2) a single blood culture positive for a gram-negative organism was not considered to constitute a minor microbiological criterion when applying the modified Duke criteria; and 3) patients with endocarditis due to anaerobes, Brucella species, HACEK organisms, or other fastidious gram-negative pathogens (for example, Pasteurella species) or polymicrobial infections were excluded. Definitions We used published definitions of health carerelated variables (15, 16). Nonnosocomial health careassociated infection was defined as a health careassociated infection that was not acquired as a hospital inpatient (for example, hemodialysis, outpatient cancer chemotherapy, or receipt of intravenous antibiotics at home) (16). A nosocomial infection was defined as a health careassociated infection that was acquired after at least 48 hours as a hospital inpatient. Prosthetic endocarditis was defined as endocarditis involving a prosthetic heart valve or implanted endovascular device, such as a permanent cardiac pacemaker, cardioverter defibrillator, or aortic stent. Statistical Analysis Patients with definite non-HACEK gram-negative bacillus endocarditis were compared with all other patients with definite endocarditis in the ICE-PCS database. Continuous variables are presented as medians and 25th and 75th percentiles. Categorical variables are presented as frequencies and percentages of the specified group. Univariable comparisons were made by using the Wilcoxon rank-sum test or the chi-square test as appropriate. For all tests, a P value of 0.05 or less was considered statistically significant. Missing data for each variable were excluded from the denominator as indicated in Table 1. All statistical analyses were performed by using SAS software (version 8.2, SAS Institute, Cary, North Carolina). Table 1. Frequency of Individual Duke Criteria among 49 Patients with Non-HACEK Gram-Negative Bacillus Endocarditis* Role of the Funding Source The study did not receive funding. Results Of the 2761 patients with definite endocarditis, 49 (1.8%) had endocarditis due to non-HACEK gram-negative bacilli. Twenty-six of these patients (53%) were enrolled from Europe; 11 (22%) from North America; and the remainder from South America, New Zealand, Australia, the Middle East, and Asia. Patient enrollment was constant throughout the study period. Characteristics of Non-HACEK Gram-Negative Bacillus Endocarditis Patients with non-HACEK gram-negative bacillus endocarditis were more likely to have had symptoms for more than 1 month than were patients infected with other pathogens (90% [95% CI, 82% to 98%] vs. 77% [CI, 75% to 79%], respectively; P= 0.035) (Table 2). Injection drug use was uncommon in patients with non-HACEK gram-negative bacillus endocarditis and in patients with endocarditis due to other organisms (4% [CI, 0% to 9%] vs. 10% [CI, 9% to 11%]; P= 0.20). In contrast, health care contact was a statistically significant risk factor for non-HACEK gram-negative bacillus endocarditis (57% [CI, 43% to 71%] vs. 30% [CI, 28% to 32%]; P< 0.001), largely because the proportion of nosocomial infections was higher in the non-HACEK gram-negative bacillus endocarditis group (39% [CI, 25% to 53%] vs. 14% [CI, 13% to 15%]; P< 0.001). The Figure shows the routes of acquisition of non-HACEK gram-negative bacillus endocarditis compared with Staphylococcus aureus endocarditis (15) and all other causes of endocarditis in the ICE-PCS database. Table 2. Characteristics of Patients with Non-HACEK Gram-Negative Bacillus Infective Endocarditis and Those with Other Causes of Endocarditis* Figure. Routes of acquisition among patients with definite endocarditis due to non-HACEK gram-negative bacilli, Staphylococcus aureus , and other pathogens. HACEK = Haemophilus species, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, or Kingella species. Implanted endovascular devices were more common in patients with non-HACEK gram-negative bacillus endocarditis than in patients with other pathogens (29% [CI, 16% to 42%] vs. 11% [CI, 10% to 12%]; P< 0.001). Patients with non-HACEK gram-negative bacillus endocarditis were also statistically significantly more likely than patients with other causes of endocarditis to have a presumed source of infection involving the genitourinary or nonoral gastrointestinal tract (35% [CI, 22% to 48%] vs. 12% [CI, 11% to 13%]; P< 0.001). A nondental invasive procedure within 60 days before symptom onset was more likely in patients with non-HACEK gram-negative bacillus endocarditis than in patients with other causes of endocarditis (38% [CI, 24% to 52%] vs. 19% [CI, 18% to 20%]; P= 0.002). Intracardiac abscesses were statistically significantly more common in patients with non-HACEK gram-negative bacillus endocarditis than in patients with endocarditis due to other organisms (25% [CI, 13% to 37%] vs. 14% [CI, 13% to 15%]; P= 0.034). The in-hospital mortality rate was 24% (CI, 12% to 36%) for patients with non-HACEK gram-negative bacillus endocarditis and 17% (CI, 16% to 18%) for patients with other causes of endocarditis (P= 0.190). Of the 49 patients with non-HACEK gram-negative bacillus endocarditis, 20 (41%) had native-valve endocarditis and 29 (59%) had prosthetic endocarditis. All 49 cases were confirmed as definite endocarditis by the modified Duke criteria: 22 (45%) were histopathologically (16 patients [33%]) or macroscopically (at surgery in 6 patients [12%]) confirmed (Table 1). Of the 16 patients with pathologic confirmation, 8 had valve cultures, 2 had device cultures, and 1 had an aortic aneurysm culture. Microbiology of Non-HACEK Gram-Negative Bacillus Endocarditis The most common pathogens in patients with non-HACEK gram-negative bacillus endocarditis were Escherichia coli (14 patients [29%]) and Pseudomonas aeruginosa (11 patients [22%]). Othe

Abacavir Use and Risk of Acute Myocardial Infarction and Cerebrovascular Events in the Highly Active Antiretroviral Therapy Era

BACKGROUND Some studies have suggested that exposure to antiretroviral therapy (ART) with abacavir is associated with an increased risk of acute myocardial infarction (AMI). METHODS Using the Veterans Health Administrations Clinical Case Registry we calculated the risk of AMI and cerebrovascular events (CVA) associated with the cumulative use of abacavir and other nucleoside combinations. We also evaluated the impact of pre-existing chronic kidney disease on the selection of abacavir versus tenofovir in the last recorded ART regimen, and on highly active antiretroviral therapy-associated AMI and CVA risks. RESULTS A total of 19,424 human immunodeficiency virus-infected patients contributed 76,376 patient-years of follow. After adjusting for age, hypercholesterolemia, hypertension, type 2 diabetes, and smoking, the hazard ratio (HR) for each year of abacavir use was 1.18 (95% confidence interval [CI], .92-1.50; P=.191) for AMI and 1.16 (95% CI, .98-1.37; P=.096) for CVA. Abacavir use was more common among patients with prior chronic kidney disease than was tenofovir use (12.46% versus 7.15%; P=.0001), and chronic kidney disease was associated with a significantly higher risk of AMI (HR, 2.41; 95% CI, 1.73-3.36), and CVA (HR, 1.80; 95% CI, 1.44-2.24). Compared with patients who received neither tenofovir nor abacavir, patients who received tenofovir had lower risk of AMI (HR, 0.16; 95% CI, .08-.33; P=.0001) and CVA (HR, 0.22; 95% CI, .15-.32; P=.001). Use of abacavir was associated with lower risk of CVA (HR, 0.60; 95% CI, .45-.79). CONCLUSIONS We observed no association between cumulative or current abacavir use and AMI or CVA. Abacavir use was more common than was tenofovir use among patients with prior chronic kidney disease, and chronic kidney disease independently predicted higher rates of AMI and CVA.

Prospective Randomized Trial of Empiric Therapy with Trimethoprim-Sulfamethoxazole or Doxycycline for Outpatient Skin and Soft Tissue Infections in an Area of High Prevalence of Methicillin-Resistant Staphylococcus aureus

ABSTRACT To evaluate empirical therapy with trimethoprim-sulfamethoxazole or doxycycline for outpatient skin and soft tissue infections in an area of high prevalence of methicillin-resistant Staphylococcus aureus, a randomized, prospective, open-label investigation was performed. The overall clinical failure rate was 9%, with all failures occurring in the trimethoprim-sulfamethoxazole group. However, there was no significant difference between the clinical failure rate of empirical trimethoprim-sulfamethoxazole therapy and that of doxycycline therapy.

Hepatitis C virus coinfection and the risk of cardiovascular disease among HIV-infected patients

Among HIV‐infected patients, hepatitis C virus (HCV) coinfection is associated with lower cholesterol levels, but it remains unclear how it affects cardiovascular outcomes.

HIV infection, cardiovascular disease risk factor profile, and risk for acute myocardial infarction

Background:Traditional cardiovascular disease risk factors (CVDRFs) increase the risk of acute myocardial infarction (AMI) among HIV-infected (HIV+) participants. We assessed the association between HIV and incident AMI within CVDRF strata. Methods:Cohort—81,322 participants (33% HIV+) without prevalent CVD from the Veterans Aging Cohort Study Virtual Cohort (prospective study of HIV+ and matched HIV− veterans) participated in this study. Veterans were followed from first clinical encounter on/after April 1, 2003, until AMI/death/last follow-up date (December 31, 2009). Predictors—HIV, CVDRFs (total cholesterol, cholesterol-lowering agents, blood pressure, blood pressure medication, smoking, diabetes) used to create 6 mutually exclusive profiles: all CVDRFs optimal, 1+ nonoptimal CVDRFs, 1+ elevated CVDRFs, and 1, 2, 3+ major CVDRFs. Outcome—Incident AMI [defined using enzyme, electrocardiogram (EKG) clinical data, 410 inpatient ICD-9 (Medicare), and/or death certificates]. Statistics—Cox models adjusted for demographics, comorbidity, and substance use. Results:Of note, 858 AMIs (42% HIV+) occurred over 5.9 years (median). Prevalence of optimal cardiac health was <2%. Optimal CVDRF profile was associated with the lowest adjusted AMI rates. Compared with HIV− veterans, AMI rates among HIV+ veterans with similar CVDRF profiles were higher. Compared with HIV− veterans without major CVDRFs, HIV+ veterans without major CVDRFs had a 2-fold increased risk of AMI (HR: 2.0; 95% confidence interval: 1.0 to 3.9; P = 0.044). Conclusions:The prevalence of optimal cardiac health is low in this cohort. Among those without major CVDRFs, HIV+ veterans have twice the AMI risk. Compared with HIV− veterans with high CVDRF burden, AMI rates were still higher in HIV+ veterans. Preventing/reducing CVDRF burden may reduce excess AMI risk among HIV+ people.

Multicenter Evaluation of Vancomycin Dosing – Emphasis on Obesity

BACKGROUND There is a paucity of data available regarding the dosing of antimicrobials in obesity. However, data are available demonstrating that vancomycin should be dosed on the basis of actual body weight. METHODS This study was conducted at 2 tertiary care medical centers that did not have pharmacy-guided vancomycin dosing programs or other institutional vancomycin dosing policies or protocols. Patients who received vancomycin between July 1, 2003, and June 30, 2006, were stratified by body mass index and randomly selected from the computer-generated queries. Patients >or=18 years of age with a creatinine clearance of at least 60 mL/min who received vancomycin for at least 36 hours were included. RESULTS Data were collected on a random sampling of 421 patients, stratified by body mass index, who met the inclusion criteria. Most patients in each body mass index category received a fixed dose of vancomycin 2 g daily divided into 2 doses (underweight 82%, normal weight 90%, overweight 86%, and obese 91%). Adequate initial dosing (>or=10 mg/kg/dose) was achieved for 100% of underweight, 99% of normal weight, 93.9% of overweight, and 27.7% of obese patients (P < .0001). Ninety-seven percent of underweight, 46% of normal weight, 1% of overweight, and 0.6% of obese patients received >or=15 mg/kg/dose recommended by several Infectious Diseases Society of America guidelines. Pharmacists also failed to correct inadequate dosing because only 3.3% of patients receiving less than 10 mg/kg/dose had their regimen changed in the first 24 hours of therapy. CONCLUSION In this multicenter pilot study, obese patients routinely received inadequate empiric vancomycin using a lenient assessment of dosing. Greater efforts should be undertaken to ensure patients receive weight-based dosing because inadequate dosing can lead to subtherapeutic concentrations and potentially worse clinical outcomes.