Biomedical subjects

Richard E Chaisson

Publications and source records attributed to Richard E Chaisson.

At least 19 recordsLinked to original sources

PubMed2006

Moxifloxacin versus ethambutol in the first 2 months of treatment for pulmonary tuberculosis.

RATIONALE: Moxifloxacin has promising preclinical activity against Mycobacterium tuberculosis, but has not been evaluated in multidrug treatment of tuberculosis in humans. OBJECTIVE: To compare the impact of moxifloxacin versus ethambutol, both in combination with isoniazid, rifampin, and pyrazinamide, on sputum culture conversion at 2 mo as a measure of the potential sterilizing activity of alternate induction regimens. METHODS: Adults with smear-positive pulmonary tuberculosis were randomized in a factorial design to receive moxifloxacin (400 mg) versus ethambutol given 5 d/wk versus 3 d/wk (after 2 wk of daily therapy). All doses were directly observed. MEASUREMENTS: The primary endpoint was sputum culture status at 2 mo of treatment. RESULTS: Of 336 patients enrolled, 277 (82%) were eligible for the efficacy analysis, 186 (67%) were male, 175 (63%) were enrolled at African sites, 206 (74%) had cavitation on chest radiograph, and 60 (22%) had HIV infection. Two-month cultures were negative in 71% of patients (99 of 139) treated with moxifloxacin versus 71% (98 of 138) treated with ethambutol (p = 0.97). Patients receiving moxifloxacin, however, more often had negative cultures after 4 wk of treatment. Patients treated with moxifloxacin more often reported nausea (22 vs. 9%, p = 0.002), but similar proportions completed study treatment (88 vs. 89%). Dosing frequency had little effect on 2-mo culture status or tolerability of therapy. CONCLUSIONS: The addition of moxifloxacin to isoniazid, rifampin, and pyrazinamide did not affect 2-mo sputum culture status but did show increased activity at earlier time points.

Adult↗

PubMed2006

The potential impact of enhanced diagnostic techniques for tuberculosis driven by HIV: a mathematical model.

OBJECTIVE: To explore the potential impact of enhanced tuberculosis (TB) diagnostic techniques as a TB control strategy in an adult population with high HIV prevalence. DESIGN: A compartmental difference-equation model of TB/HIV was developed using parameter estimates from the literature. METHODS: The impact of five TB control interventions (rapid molecular testing, mycobacterial culture, community-wide and HIV-targeted active case finding, and highly active antiretroviral therapy) on TB incidence, prevalence, and mortality was modeled in a steady-state population with an HIV prevalence of 17% and annual TB incidence of 409 per 100 000. Sensitivity analyses assessed the influence of each model parameter on the interventions' mortality impact. RESULTS: Enhanced diagnostic techniques (rapid molecular testing or culture) are each projected to reduce TB prevalence and mortality by 20% or more, an impact similar to that of active case-finding in 33% of the general community and greater than the effect achievable by case-finding or antiretroviral treatment efforts in HIV-positive patients alone. The projected impact of enhanced diagnostics on TB incidence (< 10% reduction) is smaller. The impact of TB diagnostics is sensitive to the quality of existing diagnostic standards and the level of access to diagnostic services, but is robust across a wide range of population parameters including HIV and TB incidence. CONCLUSIONS: Enhanced TB diagnostic techniques may have substantial impact on TB morbidity and mortality in HIV-endemic regions. As TB rates continue to increase in these areas, enhanced diagnostic techniques merit further consideration as TB control strategies.

AIDS-Related Opportunistic Infections↗

PubMed2006

Predicting smear negative pulmonary tuberculosis with classification trees and logistic regression: a cross-sectional study.

BACKGROUND: Smear negative pulmonary tuberculosis (SNPT) accounts for 30% of pulmonary tuberculosis cases reported yearly in Brazil. This study aimed to develop a prediction model for SNPT for outpatients in areas with scarce resources. METHODS: The study enrolled 551 patients with clinical-radiological suspicion of SNPT, in Rio de Janeiro, Brazil. The original data was divided into two equivalent samples for generation and validation of the prediction models. Symptoms, physical signs and chest X-rays were used for constructing logistic regression and classification and regression tree models. From the logistic regression, we generated a clinical and radiological prediction score. The area under the receiver operator characteristic curve, sensitivity, and specificity were used to evaluate the model's performance in both generation and validation samples. RESULTS: It was possible to generate predictive models for SNPT with sensitivity ranging from 64% to 71% and specificity ranging from 58% to 76%. CONCLUSION: The results suggest that those models might be useful as screening tools for estimating the risk of SNPT, optimizing the utilization of more expensive tests, and avoiding costs of unnecessary anti-tuberculosis treatment. Those models might be cost-effective tools in a health care network with hierarchical distribution of scarce resources.

Adult↗

PubMed2006

Weekly rifapentine/isoniazid or daily rifampin/pyrazinamide for latent tuberculosis in household contacts.

RATIONALE: Treatment of latent tuberculosis (TB) infection with weekly rifapentine and isoniazid is a potentially effective alternative to current therapies. OBJECTIVES: To compare the efficacy of weekly rifapentine/isoniazid to daily rifampin/pyrazinamide in preventing TB in household contacts of patients with pulmonary TB in Brazil. METHODS: Contacts of patients with TB were randomized to rifapentine 900 mg/isoniazid 900 mg once weekly for 12 wk or rifampin 450-600 mg/pyrazinamide 750-1,500 mg daily for 8 wk and followed for at least 2 yr. MEASUREMENTS: TB rates, adverse events, and adherence to therapy. MAIN RESULTS: A total of 399 household contacts were enrolled, 206 in the rifapentine/isoniazid arm and 193 in the rifampin/pyrazinamide arm. The median age was 34 yr, median weight was 63 kg, 60% of participants were female, and only one patient was HIV infected. Rifapentine/isoniazid was well tolerated, but the trial was halted by the investigators before completion because of unanticipated hepatotoxicity in the rifampin/pyrazinamide arm. Twenty of 193 participants (10%) receiving rifampin/pyrazinamide experienced grade 3 or 4 hepatotoxicity, compared with 2 of 206 participants (1%) on rifapentine/isoniazid (p<0.001). There were no hospitalizations or deaths due to hepatotoxicity, and all participants' liver enzyme levels returned to normal during follow-up. During follow-up, four cases of active TB developed, three in the rifapentine/isoniazid group and one in the rifampin/pyrazinamide group (1.46 vs. 0.52%; difference, 0.94%; 95% confidence interval, -1.6 to 3.7%). CONCLUSIONS: Rifapentine/isoniazid was better tolerated than rifampin/pyrazinamide and was associated with good protection against TB. Rifapentine/isoniazid weekly for 12 wk is likely a promising therapy for latent TB infection.

Adult↗

PubMed2006

Illicit drug use and HIV-1 disease progression: a longitudinal study in the era of highly active antiretroviral therapy.

This study assessed the association between longitudinal patterns of illicit drug use and clinical progression of human immunodeficiency virus (HIV) disease. Confidential computer-based interviews, which addressed illicit drug use and other factors, were completed by HIV-infected participants in Baltimore, Maryland, at 6-month intervals from 1998 onward. To assess this association, the authors used a random-effects model in which clinically defined opportunistic conditions were linked to self-reported periods of drug use, enabling four categories of drug use to be distinguished: nonusers, intermittent users during abstinent periods, intermittent users during active periods, and persistent users. Included in the analysis were 1,851 participants who completed > or = 1 survey. For participants who used drugs intermittently over time, the risk of developing new opportunistic conditions during periods of abstinence was similar to that for those who never used drugs (odds ratio = 1.2, 95% confidence interval: 0.9, 1.7). In contrast, compared with that for nonusers, the risk of opportunistic infection was significantly higher for intermittent drug users during periods of active use (odds ratio = 2.2, 95% confidence interval: 1.4, 2.9) and for persistent drug users (odds ratio = 1.9, 95% confidence interval: 1.2, 2.8). Active drug use is temporally linked to HIV disease progression and mortality. Effectively targeting and treating active substance abuse in HIV treatment settings may provide a mechanism to improve clinical outcomes.

Adult↗

PubMed2006

Combining PMTCT with active case finding for tuberculosis.

Tuberculosis (TB) is the preeminent manifestation of HIV infection and has become a leading cause of maternal mortality and morbidity in high HIV-prevalence settings. Active TB in pregnant women has potentially serious consequences for fetuses and newborns. In Soweto, South Africa, there is a more than 90% uptake of voluntary counseling and HIV testing during routine antenatal care, and almost one third of pregnant women are HIV-infected. The posttest counseling session of the prevention of mother-to-child transmission program provides an opportunity to screen HIV-infected pregnant women for TB. In this study, 370 HIV-infected pregnant women were screened for symptoms of active TB by lay counselors at the posttest counseling session. If symptomatic, they were referred to nurses who investigated them further. Eight women were found to have previously undiagnosed, smear-negative, culture-confirmed TB (2160/100,000). The mean CD4 count in those with active TB compared to those without TB was 276 x 10(6) cells per liter vs 447 x 10(6) cells per liter (P = 0.051). Symptoms most associated with active TB were hemoptysis and fever. We conclude that rates of TB in HIV-infected pregnant women are high, and screening for TB during routine antenatal care should be implemented in high HIV-prevalence settings.

Adult↗

PubMed2005

Effect of routine isoniazid preventive therapy on tuberculosis incidence among HIV-infected men in South Africa: a novel randomized incremental recruitment study.

CONTEXT: Tuberculosis preventive therapy reduces tuberculosis incidence among human immunodeficiency virus (HIV)-infected individuals in clinical trials, but implementation has been limited and there are no data on effectiveness under routine conditions. OBJECTIVE: To determine the effect on tuberculosis incidence of a clinic providing isoniazid preventive therapy to HIV-infected adults under routine conditions. DESIGN, SETTING, AND PARTICIPANTS: Randomized intervention study with a novel incremental recruitment design. Between 1999 and 2001 (before antiretroviral therapy was available), 1655 HIV-infected male employees of a South African gold-mining company (median age, 37 years) were enrolled in the study. Median follow-up was 22.1 months. INTERVENTION: Employees were invited in random sequence to attend a workplace HIV clinic. Isoniazid, 300 mg/d, was self-administered for 6 months among attendees with no evidence of active tuberculosis. MAIN OUTCOME MEASURE: Incidence of tuberculosis (including both first and recurrent episodes) during the periods before and after clinic enrollment. RESULTS: A total of 1016 of 1655 men included in the analysis attended the clinic at least once. Six hundred seventy-nine (97%) of 702 men eligible to start primary isoniazid preventive therapy did so. The tuberculosis incidence rate before vs after clinic enrollment was 11.9 vs 9.0 per 100 person-years, respectively (incidence rate ratio [IRR] after adjustment for calendar period, 0.68; 95% confidence interval [CI], 0.48-0.96). In a multivariable analysis adjusting for calendar period, age, and silicosis grade, the tuberculosis IRR for clinic enrollment was 0.62 (95% CI, 0.43-0.89). In a further analysis excluding individuals with a history of tuberculosis (and, hence, ineligible for isoniazid preventive therapy), the adjusted IRR for clinic enrollment was 0.54 (95% CI, 0.35-0.83). CONCLUSIONS: Enrollment in a clinic offering primary isoniazid preventive therapy to HIV-infected adults reduced tuberculosis incidence by 38% overall and by 46% among individuals with no history of tuberculosis prior to the study. Tuberculosis incidence remained high despite isoniazid preventive therapy, and further work is needed to determine how to use additional interventions most effectively to reduce morbidity and mortality due to tuberculosis in HIV-infected persons.

AIDS-Related Opportunistic Infections↗

PubMed2005

HIV/AIDS and antiretroviral treatment knowledge, attitudes, beliefs, and practices in HIV-infected adults in Soweto, South Africa.

A cross-sectional study of knowledge, attitudes, beliefs, and practices (KABPs) toward HIV and antiretroviral therapy (ART) was conducted in Soweto, South Africa, using a standardized validated questionnaire. Of 105 HIV clinic patients evaluated, 70% of whom were not on ART, 89% had good knowledge about the cause of HIV infection and 83% knew about modes of transmission. Fifty-nine percent reported they were not worried about ART side effects. Sixty-five percent agreed that missing ART doses can lead to disease progression. Ninety percent had disclosed their HIV serostatus to 1 or more persons, but only 62% of those with a current sexual partner reported having told that partner. Approximately 80% reported that if they were taking ART, they would not be worried about family or friends finding out. Forty-nine percent believed that ART can cure HIV, a belief that was associated with a low level of education (P<0.001). Overall, knowledge of the cause of HIV/AIDS, modes of transmission, and importance of ART adherence was good in our study population. Further research is warranted to assess the extent to which this knowledge and attendant attitudes predict ART adherence levels. The low rate of HIV serostatus disclosure to sexual partners calls for multidimensional interventions to reduce HIV-related stigma.

Adult↗

PubMed2005

The effect of antiretroviral therapy on liver disease among adults with HIV and hepatitis C coinfection.

In the era of antiretroviral therapy (ART), liver disease has emerged as an important cause of death among persons with human immunodeficiency virus (HIV)/hepatitis C virus (HCV) coinfection. The objective of this study was to estimate the burden of liver disease and evaluate determinants of liver fibrosis and necroinflammatory activity among HIV/HCV coinfected patients receiving ART. We studied 112 randomly selected and 98 referred HCV-infected patients undergoing care in the Johns Hopkins University HIV clinic. Liver disease was characterized clinically and histologically. Of the 210 individuals studied--64% of whom had received ART within 2 years of liver disease assessment--33% had no fibrosis (F0), and 26% had bridging fibrosis or cirrhosis (> or =F3). The median necroinflammatory activity score was 3 (range, 0-9 of 18). ART was not associated with fibrosis; however, significantly less hepatic necroinflammatory activity was observed among persons who had received highly active antiretroviral therapy longer (P = .02) and more effectively (defined by HIV RNA suppression; P < .01). Twelve percent of individuals had previous ART-associated liver enzyme elevations (grades 3-4), but liver fibrosis was not more severe if the liver enzyme elevation resolved. On the other hand, liver fibrosis was more severe in persons with persistent liver enzyme elevations (grades 1-4). In conclusion, despite widespread exposure to ART and documented instances of ART-related hepatitis, we found no evidence that ART caused serious histological liver disease. Recognition of bridging fibrosis and cirrhosis in some but not most patients underscores the importance of identifying and treating liver disease in HIV/HCV coinfected persons.

Adult↗

PubMed2004

Hepatotoxicity associated with protease inhibitor-based antiretroviral regimens with or without concurrent ritonavir.

OBJECTIVE: To determine the incidence of significant liver enzyme elevations following the initiation of protease inhibitor (PI)-based antiretroviral therapy (ART) with or without pharmacokinetic boosting with ritonavir (RTV), and to define the role of chronic viral hepatitis in its development. DESIGN: Prospective, cohort analysis of 1161 PI-naive, HIV-infected patients receiving RTV-boosted (lopinavir, indinavir and saquinavir) and unboosted PI-based ART (indinavir, nelfinavir) that had at least one liver enzyme measurement before and during therapy. METHODS: The incidence of grade 3 and 4 liver enzyme elevations among persons with and without hepatitis B and/or C co-infection treated with PI-based ART were compared. Severe hepatotoxicity was defined as an increase in serum liver enzyme >/= 5-times the upper limit of the normal range or 3.5-times an elevated baseline level. RESULTS: The incidence of grade 3 or 4 elevations among PI-naive patients was: nelfinavir, 11%; lopinavir/RTV (200 mg/day), 9%; indinavir, 13%; indinavir/RTV (200-400 mg/day), 12.8%; and saquinavir/RTV (800 mg/day), 17.2%. The risk was significantly greater among persons with chronic viral hepatitis (63% of cases); however, the majority of hepatitis C virus (HCV)-infected patients treated with nelfinavir (84%), saquinavir/RTV (74%), indinavir, 86%, indinavir/RTV (90%) or lopinavir/RTV (87%) did not develop hepatotoxicity. CONCLUSIONS: Our data suggest that the lopinavir/RTV is not associated with a significantly increased risk of hepatotoxity among HCV-infected and uninfected patients compared with an alternative PI-based regimen, nelfinavir. Accordingly, other medication-related factors (e.g, efficacy and non-hepatic toxicity) should guide individual treatment decisions.

AIDS-Related Opportunistic Infections↗

PubMed2004

Does tuberculosis increase HIV load?

BACKGROUND: The effect that tuberculosis (TB) has on human immunodeficiency virus (HIV) disease progression is not clearly understood. METHODS: In an observational cohort study of HIV-infected adults in South Africa, baseline and final HIV load were compared between individuals who experienced an episode of TB (n=30) during follow-up and control subjects (n=56) matched by baseline CD4 cell count and follow-up time; linear regression modeling was used to control for confounding. RESULTS: Mean HIV load was higher in the TB group than in the non-TB control group for both baseline (4.73 vs. 4.24 log(10) copies/mL; P=.003) and final values (5.02 vs. 4.34 log(10) copies/mL; P<.001). After adjustment for baseline HIV load and World Health Organization HIV stage, the difference in final HIV load was 0.24 log(10) copies/mL (95% confidence interval, -0.01 to 0.50 log(10) copies/mL; P=.06). CONCLUSIONS: Poor prognosis for HIV-infected individuals after TB may be due to preexisting high HIV load rather than to the TB event itself. An episode of TB was associated with a small adjusted increase in HIV load at the end of the study--an increase that would not be regarded as clinically significant in an individual but could have some effect on HIV disease progression or HIV transmission at the population level. Prevention of TB is important for the reduction of HIV-related morbidity and mortality; however, antiretroviral therapy is required to have a major effect on survival in individuals with HIV disease.

AIDS-Related Opportunistic Infections↗

PubMed2004

Moxifloxacin-containing regimens of reduced duration produce a stable cure in murine tuberculosis.

In a recent experimental study using the mouse model of tuberculosis, treatment with a combination of rifampin, moxifloxacin, and pyrazinamide was able to shorten the time to negative lung cultures by up to 2 months compared with the standard regimen of rifampin, isoniazid, and pyrazinamide. To confirm that this substitution of moxifloxacin for isoniazid permits a shorter duration of treatment, a second study was performed in which mice were assessed for relapse after treatment with combination therapy for 3, 4, 5, or 6 months. Although no relapse was observed among mice treated for at least 4 months with rifampin, moxifloxacin, and pyrazinamide, mice treated with rifampin, isoniazid, and pyrazinamide required 6 months of treatment before no relapse could be detected. For mice treated with rifampin, moxifloxacin, and pyrazinamide, similar efficacy was noted whether pyrazinamide was administered for 1 month, 2 months, or the entire duration of therapy. These results suggest that the use of rifampin, moxifloxacin, and pyrazinamide may substantially shorten the duration of therapy needed to cure human tuberculosis and that the full benefit of pyrazinamide in this regimen may be realized after just 1 month of treatment.

Animals↗

PubMed2004

Hepatotoxicity of rifampin and pyrazinamide in the treatment of latent tuberculosis infection in HIV-infected persons: is it different than in HIV-uninfected persons?

BACKGROUND: In 2000, results of a multinational trial demonstrated that a 2-month course of rifampin and pyrazinamide (RZ) was as effective as isoniazid (INH) in reducing tuberculosis in human immunodeficiency virus (HIV)-infected individuals with latent tuberculosis infection (LTBI). After the release of new guidelines, the Centers for Disease Control and Prevention received reports of severe hepatotoxicity associated with the use of the RZ regimen for the treatment of LTBI in the general population. To better understand the occurrence of hepatotoxicity in an HIV-infected population, we conducted a more detailed analysis of the liver function test results obtained in the multinational trial of RZ. METHODS: At study entry, patients were required to have a bilirubin level of < or =2.5 mg/dL and both an aspartate aminotransferase (AST) level and an alkaline phosphatase level of < or =5 times the upper limit of normal. Patients with acute hepatitis were excluded. At months 1 and 2 of the study, all patients had bilirubin and AST levels measured. RESULTS: There was no difference between the RZ and INH groups with regard to AST level or bilirubin level at baseline. An increase in the AST level of > or =40 U/L was associated with the use of INH and older age; and an increase in the bilirubin level of > or =0.5 mg/dL was associated with the use of RZ, male sex, and nonwhite race (P<.05). An absolute AST level of >250 U/L occurred in 12 of 745 INH recipients and in 15 of 721 RZ recipients (P=.56), and an absolute bilirubin level of >2.5 mg/dL occurred in 5 of 743 INH recipients and 13 of 718 RZ recipients (P=.06). CONCLUSIONS: These data demonstrate very little liver injury associated with either INH or RZ in the HIV-infected subjects, leaving unclear the reasons for serious RZ-related liver damage in the general population.

Adolescent↗

PubMed2004

Differences in HIV disease progression by injecting drug use in HIV-infected persons in care.

BACKGROUND: In the United States and many Western countries, injecting drug use continues to be an important cause of HIV infection. This has important clinical and public health implications if injecting drug users (IDUs) have greater barriers to antiretroviral effectiveness than other risk groups. We assessed if there were differences between HIV-infected IDUs and non-IDU patients in the development of AIDS-defining illnesses (ADIs) from the time the patients started their first combination antiretroviral therapy (CART) regimen. METHODS: We compared clinical outcomes for IDU patients (n = 827) with those for non-IDU patients (n = 1314) after they started CART. We controlled for financial access, because all patients had access to CART through insurance or a drug assistance program. The incidence (number of ADI cases per 100 person-years) was compared for IDUs and non-IDUs from 1995 through 2002. Incidence ratios were calculated for IDUs compared with non-IDUs. Risk factors for development of ADIs were assessed using negative binomial regression. RESULTS: From 1995-1996 to 2001-2002, there was a decline in ADI incidence among IDUs from 31.9 to 16.2 cases per 100 person-years of follow-up. Over the same time, there was a decline in ADI incidence among non-IDUs from 37.0 to 9.7 cases per 100 person-years. The incidence ratio (incidence among IDUs compared with that among non-IDUs) increased from 0.87 (95% confidence interval [CI], 0.65-1.15) to 1.67 (95% CI, 1.25-2.18) from 1995-1996 to 2001-2002. By negative binomial regression, the incidence ratio for ADIs among IDUs versus non-IDUs increased to 1.45 (95% CI, 1.21-1.75), after 1998, adjusting for differences in demographic, clinical, and treatment factors. CONCLUSIONS: The relative incidence of ADIs among IDUs with access to treatment increased approximately 50% compared with non-IDUs since 1999. This suggests greater barriers to the effective use of CART for IDUs, resulting in a higher individual and public health burden of clinical HIV disease. It will be important to understand reasons for this growing difference and to implement appropriate interventions to improve the effective use of CART for IDUs.

Acquired Immunodeficiency Syndrome↗

PubMed2004

Mycobacterium avium complex in patients with HIV infection in the era of highly active antiretroviral therapy.

Disseminated Mycobacterium avium complex (MAC) infection is a common complication of late-stage HIV-1 infection. Since the advent of highly active antiretroviral therapy (HAART), the rate of MAC infection has declined substantially, but patients with low CD4 cell counts remain at risk. Among patients in the Johns Hopkins cohort with advanced HIV disease, the proportion developing MAC has fallen from 16% before 1996 to 4% after 1996, with a current rate of less than 1% per year. Factors associated with developing MAC include younger age, no use of HAART, and enrollment before 1996. Prophylaxis with azithromycin or clarithromycin is recommended for all patients with CD4 counts less than 50 cells/mL. Optimum treatment for disseminated MAC includes clarithromycin and ethambutol, and another investigation suggests that the addition of rifabutin might reduce mortality. Both prophylaxis and treatment of disseminated MAC can be discontinued in patients who have responded to HAART, and specific guidelines for withdrawing treatment have been published. Although HAART has altered the frequency and outcome of MAC infection, it remains an important complication of AIDS.

AIDS-Related Opportunistic Infections↗

PubMed2003

Improved outcomes with earlier initiation of highly active antiretroviral therapy among human immunodeficiency virus-infected patients who achieve durable virologic suppression: longer follow-up of an observational cohort study.

On the basis of studies with relatively short follow-up, treatment guidelines currently recommend that highly active antiretroviral therapy (HAART) be initiated in asymptomatic human immunodeficiency virus-infected patients when the CD4+ lymphocyte count is < or =200 cells/mm3. We assessed the development of a new opportunistic infection or death among 1173 patients initiating HAART. Durable virologic suppression was defined as having more undetectable (<400 copies/mL) than detectable virus loads after the initiation of therapy. The median durations of therapy and follow-up were 29 and 36 months, respectively. Among patients who achieved durable virologic suppression, those with baseline CD4+ lymphocyte counts of <200 cells/mm3 tended to progress faster than those with baseline CD4+ lymphocyte counts of 201-350 cells/mm3 (P=.09) and progressed faster than those with baseline CD4+ lymphocyte counts of >350 cells/mm3 (P=.01). Among those with durable virologic suppression, there was no difference in disease progression between those with baseline CD4+ lymphocyte counts of 201-350 cells/mm3 and those with durable virologic suppression with baseline CD4+ lymphocyte counts of >350 cells/mm3 (P=.40). Initiating HAART with a CD4+ lymphocyte count of <200 cells/mm3 was associated with a higher risk of disease progression, even with durable virologic suppression. HAART should be initiated at CD4+ lymphocyte counts of >200 cells/mm3.

Adult↗

PubMed2003

Moxifloxacin-containing regimen greatly reduces time to culture conversion in murine tuberculosis.

Tuberculosis continues to be a major cause of morbidity and mortality in the world. The expansion of tuberculosis control programs has been limited by the lengthy and cumbersome nature of current chemotherapeutic regimens. A new drug that improves the sterilizing activity of current regimens would reduce the duration of therapy without sacrificing efficacy, thereby enhancing treatment completion rates and preserving precious public health resources. The new 8-methoxyfluoroquinolone moxifloxacin has potent activity against both actively multiplying and nonactively multiplying tubercle bacilli. Using a murine model that is representative of chemotherapy for human tuberculosis, we show that the combination of moxifloxacin, rifampin, and pyrazinamide reduced the time needed to eradicate Mycobacterium tuberculosis from the lungs of infected mice by up to 2 months when compared with the standard regimen of isoniazid, rifampin, and pyrazinamide. The findings suggest that this regimen has the potential to substantially shorten the duration of therapy needed to cure human tuberculosis.

Analysis of Variance↗

PubMed2003

Efficacy of secondary isoniazid preventive therapy among HIV-infected Southern Africans: time to change policy?

OBJECTIVE: To determine the efficacy of secondary preventive therapy against tuberculosis (TB) among gold miners working in South Africa. DESIGN: An observational study. SETTING: Health service providing comprehensive care for gold miners. METHODS: The incidence of recurrent TB was compared between two cohorts of HIV-infected miners: one cohort (n = 338) had received secondary preventive therapy with isoniazid (IPT) and the other had not (n = 221). RESULTS: The overall incidence of recurrent TB was reduced by 55% among men who received IPT compared with those who did not (incidence rates 8.6 and 19.1 per 100 person-years, respectively; incidence rate ratio, 0.45; 95% confidence interval 0.26-0.78). The efficacy of isoniazid preventive therapy was unchanged after controlling for CD4 cell count and age. The number of person-years of IPT required to prevent one case of recurrent TB among individuals with a CD4 cell count < 200 x 106 cells/l, and > or = 200 x 106 cells/l was 5 and 19, respectively. CONCLUSION: Secondary preventive therapy reduces TB recurrence: the absolute impact appears to be greatest among individuals with low CD4 cell counts. International TB preventive therapy guidelines for HIV-infected individuals need to be expanded to include recommendations for secondary preventive therapy in settings where TB prevalence is high.

Adult↗