Selection Of Candidates For Therapy Research Articles

Treatment of latent tuberculosis infection: An update

Isoniazid (INH) has been the mainstay of treatment of latent tuberculosis infection for almost 50 years. The currently recommended preferred regimen is 9 months daily self-administered INH (9H); this has efficacy of more than 90% if completed properly. Unfortunately, INH is associated with serious adverse events, including hepatotoxicity. Although risk factors for this complication are well established, allowing for better selection of candidates for therapy, this complication still occurs, and is occasionally fatal. Hence close follow up of patients is necessary, increasing the cost and complexity of treatment. This problem, plus the lengthy duration, results in poor acceptance by patients and providers, and poor adherence by patients. As a result, many preventable cases of tuberculosis continue to occur, and the public health impact of latent tuberculosis infection treatment is suboptimal. These problems have spurred interest in finding shorter, safer and cheaper alternative regimens, with similar efficacy. Of the many regimens that have been examined, 2 months of rifampin and pyrazinamide has excellent efficacy-in experimental studies in mice and randomized trials, largely in HIV-infected persons. However, while the safety of 2 months of rifampin and pyrazinamide appears acceptable in HIV-infected persons and children, in non-HIV-infected adults this regimen is associated with an unacceptably high rate of severe liver toxicity. Three to four months of INH and rifampin has had equivalent effectiveness as 6 months INH in several randomized trials. However, completion of therapy and toxicity has been the same as with INH-possibly because two drugs are taken rather than one. The fourth commonly studied regimen is 4 months rifampin. This has been found to have significantly better completion than 9H, with significantly less toxicity, especially hepatotoxicity. However, only one trial has evaluated efficacy and effectiveness of mono-rifampin therapy. In this trial, 3 months rifampin had somewhat better efficacy than either 3 months of isoniazid and rifampin (3HR) or 6 months isoniazid. Two large scale trials are ongoing; one is comparing efficacy and effectiveness of 9H with 4 months rifampin (both daily and self-administered), while the second, which is nearing completion, compares daily self-administered 9H with 3 months directly observed once weekly INH combined with rifapentine. The results of these two trials will likely shape future recommendations substantially.

A Personalized Approach to Optimize Hepatitis B Treatment in Treatment-naive Patients

In a treatment-naive patient with chronic hepatitis B, a personalized approach allows treatment efficacy to be optimized. Firstly, the selection of good candidates for therapy is crucial. Patients with chronic active hepatitis B--with relatively low levels of HBV DNA replication (<10(9) copies/ml) and relatively high alanine aminotransferase (ALT) levels--are good candidates for therapy. By contrast, patients with chronic hepatitis B in the immunotolerance phase, who have high levels of HBV DNA and persistently normal ALT levels, as well as inactive hepatitis B surface antigen (HBsAg) carriers with low HBV DNA and normal ALT levels do not have an indication for therapy as they are poor responders. Secondly, the characteristics of the patient (for example, gender, age, immune status, general health status and comorbidities), the characteristics of the liver disease (for example, presence of cirrhosis and liver function) and the characteristics of the virus (for example, genotype) are important when assessing the chance of success and when choosing the best therapeutic strategy (nucleoside/nucleotide analogue or interferon). Thirdly, during therapy, the antiviral effect--assessed by decrease in HBV DNA level--allows an individualized response-guided approach. In addition, quantification of HBsAg after 3-6 months of interferon therapy appears to be a good predictor of sustained virological response after treatment and HBsAg clearance. Continuing interferon therapy until week 48 is justified in patients with a significant decrease in HBsAg. Ongoing and future studies will provide useful information regarding prolonging interferon therapy beyond 48 weeks in some patients in order to increase efficacy, and also regarding the role of combination therapy with interferon and potent nucleoside/nucleotide analogues, such as entecavir or tenofovir disoproxil fumarate.

EPG therapy for children with long‐standing speech disorders: predictions and outcomes

This paper reports on a project using a series of single subjects to investigate the effectiveness of using electropalatography (EPG) in treating ten children with persisting speech difficulties of no known organic aetiology. The aims of the project were two‐fold, firstly to assess whether the subjects selected benefited from this treatment, and secondly to investigate whether it was possible to predict which children would make maximum improvement. A number of factors were identified as possible predictors for successful EPG therapy and subjects were then ranked according to these predictions. Baseline measures of each subject's speech were taken using word lists. Scores reflected the correct number of realizations of consonants produced by each subject. Subjects received the same number of therapy sessions and were then re‐tested. Scores before and after therapy were compared and found to be significantly different although the initial predictions as to the magnitude of improvement for each subject were not verified. The selection of appropriate candidates for therapy and the need for objective means of establishing effectiveness are discussed.