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Biomedical subjects

Richard E Chaisson

Publications and source records attributed to Richard E Chaisson.

45 records · Page 3Linked to original sources
PubMed2002

Hepatotoxicity associated with nevirapine or efavirenz-containing antiretroviral therapy: role of hepatitis C and B infections.

Hepatologists are frequently asked to evaluate human immunodeficiency virus (HIV)-infected patients with abnormal liver enzymes and to assess the causal role of medications, such as antiretroviral drugs. Recently, the use of HIV-1 specific non-nucleoside reverse transcriptase inhibitors (NNRTIs), including nevirapine (NVP) and efavirenz (EFV), has been associated with severe hepatic injury. We prospectively studied the incidence of severe hepatotoxicity (grade 3 or 4 change in alanine or aspartate transaminase levels) among 568 patients receiving NNRTI-containing antiretroviral therapy, including 312 and 256 patients prescribed EFV and NVP, respectively. Hepatitis C virus (HCV) and hepatitis B virus (HBV) were detected in 43% and 7.7% of patients, respectively. Severe hepatotoxicity was observed in 15.6% of patients prescribed NVP and 8.0% of those prescribed EFV, but only 32% of NVP and 50% of EFV-associated episodes were detected during the first 12-weeks of therapy. The risk was significantly greater among persons with chronic viral hepatitis (69% of cases) and those prescribed concurrent protease inhibitors (PIs) (82% of cases). Nonetheless, 84% of patients with chronic HCV or HBV did not experience severe hepatotoxicity. Severe hepatotoxicity occurs throughout the course of NNRTI therapy and is more common among patients prescribed nevirapine, those coinfected with HCV or HBV, and those coadministered protease inhibitors.

Adult↗
PubMed2002

Characteristics of injection drug users who utilize tuberculosis services at sites of the Baltimore city needle exchange program.

OBJECTIVE: To describe characteristics of needle-exchange program (NEP) participants who utilized tuberculosis services from an NEP site. METHODS: Between June 1998 and May 1999, tuberculosis services were advertised and offered to Baltimore, Maryland, NEP participants. Demographic and tuberculosis-specific data were collected on participants who self-selected into services. Analyses were based on being tuberculin skin tested, returning for a skin test reading, and testing tuberculin positive. RESULTS: Among 691 contacts with NEP participants, this service performed 296 tuberculin tests, with an 84% return rate for skin test reading. Participants were 32% female, 87% African American, and 11% employed. Higher frequency of NEP visits was positively associated with requesting tuberculosis services and returning for skin test reading. Among those who returned for skin test reading, longer smoking duration and problems getting food in the past year due to a lack of money were associated with a positive test. CONCLUSIONS: Utilization of a tuberculosis service and high return rates can be achieved among NEP participants without formal recruitment strategies. Frequent exchange appears to facilitate return visits for NEP-based tuberculosis screening, which may imply accessibility for frequent exchangers. More extensive health services at sites of the Baltimore NEP appear to be warranted, with particular attention paid to effectiveness for frequent exchangers.

Adult↗
PubMed2002

Performance of the microscopic observation drug susceptibility assay in drug susceptibility testing for Mycobacterium tuberculosis.

The drug susceptibility testing performance of a broth-based method with microscopic reading of bacillary growth, the microscopic observation drug susceptibility (MODS) assay, was compared to that of the reference 7H10 agar method of proportion by using 53 isolates of Mycobacterium tuberculosis from persons at risk for multidrug-resistant TB. For isoniazid (0.1 micro g/ml) and rifampin (2.0 micro g/ml), there was 100% agreement between MODS results read at day 11 and the reference method. Levels of agreement for ethambutol tested at 2.5 and 7.5 micro g/ml were 70 and 58%, respectively. Levels of agreement for streptomycin tested at 2.0 and 6.0 micro g/ml were 77 and 51%, respectively. For isoniazid and rifampin drug susceptibility testing, MODS is as accurate as and more rapid than the reference method.

Antitubercular Agents↗
PubMed2002

Field evaluation of a rapid immunochromatographic test for tuberculosis.

Rapid diagnostic tests for tuberculosis (TB) are needed to facilitate early treatment of TB and prevention of Mycobacterium tuberculosis transmission. The ICT Tuberculosis test is a rapid, card-based immunochromatographic test for detection of antibodies directed against M. tuberculosis antigens. The objective of the study was to evaluate the performance of the ICT Tuberculosis test for the diagnosis of active pulmonary TB (PTB) with whole blood, plasma, and serum from patients suspected of having PTB and from asymptomatic controls in a setting with a high prevalence of PTB. Seventy patients suspected of having PTB (and who were later confirmed to have or not to have PTB by use of M. tuberculosis culture as the "gold standard") and 42 controls were studied. Twenty-one controls were neither vaccinated with Mycobacterium bovis bacillus Calmette-Guérin (BCG) nor tuberculin skin test (TST) positive (group A controls), and 21 controls were TST positive and/or had previously been vaccinated with BCG (group B controls). Study subjects were drawn from one hospital and one primary health care unit in Rio de Janeiro City, Brazil. One version of the test (ICT-1) was evaluated by using whole blood, plasma, and serum samples. Sera obtained for this study were frozen and later tested with a manufacturer-modified version of the test (ICT-2). Among the patients suspected of having PTB, the sensitivities of the ICT-1 with whole blood, serum, and plasma were 83, 65, and 70%, respectively, and the specificities were 46, 67, and 56%, respectively. Among the group A controls, the specificities of ICT-1 with the three specimen types were 95, 100, and 95%, respectively. Among the group B controls, the specificities of ICT-1 with the three specimen types were 71, 86, and 86%, respectively. Among the patients suspected of having PTB, the sensitivity of ICT-2 was 70% and the specificity was 65%. Among the group A controls, the specificity of ICT-2 was 95%, and among the group B controls, the specificity of ICT-2 was 81%. With a 29% observed prevalence of PTB among patients suspected of having PTB, the positive predictive values of the ICT tests ranged from 39 to 50% and the negative predictive values ranged from 82 to 87%. The ICT Tuberculosis tests were not sufficiently predictive to warrant their widespread use as routine diagnostic tests for PTB in this setting. However, further evaluation of these tests in specific epidemiologic settings may be warranted.

Adult↗
PubMed2002

Comparison of C(18)-carboxypropylbetaine and standard N-acetyl-L-cysteine-NaOH processing of respiratory specimens for increasing tuberculosis smear sensitivity in Brazil.

Techniques to improve the sensitivity of smear microscopy would facilitate early tuberculosis (TB) diagnosis and disease control, especially in low-income countries where the positive predictive value is high. C(18)-carboxypropylbetaine (CB-18) is a zwitterionic detergent that helps to compensate for the innate buoyancy of mycobacteria, potentially enhancing recovery by centrifugation. Previous data suggest that CB-18 may increase the sensitivity of smear, culture, and molecular amplification diagnostic testing. The goal of the present study was to evaluate if the sensitivity of the smear technique using light microscopy could be improved by treating respiratory samples with CB-18. In the first phase, respiratory specimens were collected consecutively from patients with suspected pulmonary tuberculosis in a tertiary-care hospital in Rio de Janeiro, Brazil (236 specimens were analyzed). After protocol modifications, another 120 respiratory specimens were evaluated. The standard technique was N-acetyl-L-cysteine with sodium hydroxide (NALC-NaOH) treatment, smear concentration with centrifugation, and Ziehl-Neelsen staining. Culture on Löwenstein-Jensen slants was performed on all specimens for use as the "gold standard." No specimens from patients undergoing active TB treatment were included. The initial protocol for CB-18 processing resulted in a sensitivity of 59.6% and specificity of 96.8% compared to standard processing with a sensitivity of 66.0% and specificity of 96.8%. Using the modified protocol, the sensitivity of CB-18 increased to 71.4% with a specificity of 97.0% versus standard processing with a sensitivity of 61.9% and a specificity of 99.0%. The diagnostic yield of acid-fast bacillus smear with CB-18 in the absence of fluorescence microscopy and PCR compared to standard processing with NALC-NaOH was not significantly different, although the power to detect a difference by the modified assay was low.

Acetylcysteine↗
PubMed2002

Tuberculosis screening in an at-risk immigrant Hispanic population in Baltimore city: an academic health center/local health department partnership.

Tuberculosis (TB) is endemic and epidemic throughout the world. More people will die of TB this year then in any previous year in modern history. However, in the United States successful TB control programs have resulted in low morbidity and low mortality here. Globalization and immigration threatens this control potentially bringing the infection to a here-to-fore complacent United States. This article describes a unique partnership between a community health program of a School of Nursing and a local health department chest clinic to find, screen and treat a population of Hispanic immigrants otherwise difficult to reach because of legal, language, cultural and socioeconomic barriers. Working through community organizations and limiting, and/or eliminating cultural barriers accomplished a high level of screening and treatment in a population with a significant incidence of latent tuberculosis infection. The program was of great satisfaction to the students and faculty involved; the personnel of a seriously under-financed health department and the community participants involved.

Adolescent↗
PubMedDate not supplied

Gender differences in indices of opioid dependency and medical comorbidity in a population of hospitalized HIV-infected African-Americans.

We examined gender differences in drug use patterns and in medical presentation among 520 hospitalized, HIV-infected African-Americans. Substance abuse history was self-reported, and medical data were obtained by chart review. Overall, 321 (65%) reported ever having used heroin, with equivalent rates in men and women. Women were more likely to report current use, to have sought treatment, and tended to feel more dependent on heroin than men. Among heroin users, women were more likely to be admitted for conditions related to drug use, rather than AIDS, and to have CD4 counts > 200/mm3. These gender differences in opioid dependency and medical comorbidity may indicate a need for alternative treatment approaches for men and women.

Adult↗