Single Dose Of Rifampicin Research Articles

The Leprosy Post-Exposure Prophylaxis (LPEP) programme: update and interim analysis.

Innovative approaches are required to further enhance leprosy control, reduce the number of people developing leprosy, and curb transmission. Early case detection, contact screening, and chemoprophylaxis currently is the most promising approach to achieve this goal. The Leprosy Post-Exposure Prophylaxis (LPEP) programme generates evidence on the feasibility of integrating contact tracing and single-dose rifampicin (SDR) administration into routine leprosy control activities in different settings. The LPEP programme is implemented within the leprosy control programmes of Brazil, Cambodia, India, Indonesia, Myanmar, Nepal, Sri Lanka and Tanzania. Focus is on three key interventions: tracing the contacts of newly diagnosed leprosy patients; screening the contacts for leprosy; and administering SDR to eligible contacts. Country-specific protocol adaptations refer to contact definition, minimal age for SDR, and staff involved. Central coordination, detailed documentation and rigorous supervision ensure quality evidence. Around 2 years of field work had been completed in seven countries by July 2017. The 5,941 enrolled index patients (89·4% of the registered) identified a total of 123,311 contacts, of which 99·1% were traced and screened. Among them, 406 new leprosy patients were identified (329/100,000), and 10,883 (8·9%) were excluded from SDR for various reasons. Also, 785 contacts (0·7%) refused the prophylactic treatment with SDR. Overall, SDR was administered to 89·0% of the listed contacts. Post-exposure prophylaxis with SDR is safe; can be integrated into the routines of different leprosy control programmes; and is generally well accepted by index patients, their contacts and the health workforce. The programme has also invigorated local leprosy control.

Chemoprophylaxis of leprosy with rifampicin in contacts of multibacillary patients: study protocol for a randomized controlled trial

BackgroundThe annual new-case detection rate for leprosy, while generally stable over the last decade, shows that transmission rates have remained stagnant despite the successful worldwide administration of multidrug therapy since the 1980s. As such, novel control strategies are urgently needed. Focusing on managing leprosy patient contacts, the most susceptible to contracting the disease, has been seen as a potential strategy in limiting the spread of leprosy as shown by a number of recent epidemiological studies. Immunoprophylaxis with Bacillus Calmette-Guérin (BCG) has been seen as an effective preventive measure due to its ability to stimulate the development of cellular immunity which is essential in controlling the disease, especially in its multibacillary (MB) forms. The association of immunoprophylaxis with chemoprophylaxis in a single dose of rifampicin has been shown to be a promising preventive strategy, although a variety of studies have found instances of early case detection just a few months after BCG vaccination.Methods/designThe present study is a phase IV chemoprophylactic clinical trial consisting of administration of a single dose of rifampicin in MB leprosy patient contacts under care at the Souza Araújo Outpatient Clinic/FIOCRUZ as part of a randomized (2:1), double-blind, placebo-controlled study. It is comprised of two groups: 1) rifampicin + BCG; and 2) placebo + BCG.DiscussionThe aim is to evaluate whether the use of chemoprophylaxis with a single dose of rifampicin in MB leprosy patient contacts prior to the BCG vaccine would be able to prevent the onset of leprosy in those cases that may occur just a few months after vaccination. Contact subclinical infections (polymerase chain reaction) and the immunological parameters (anti-PGL-1, anti-LID-1, and IFN-γ) will be evaluated and the results will be compared after 12 months of follow-up.Trial registrationThe Brazilian Registry of Clinical Trials (ReBEC), RBR-69QK5P. Retrospectively registered on 1 June 2017.

Minimal essential data to document contact tracing and single dose rifampicin (SDR) for leprosy control in routine settings: a practical guide

In leprosy control there is a renewed interest in active case finding, which is increasingly being combined with chemoprophylactic interventions to try and reduce M. leprae transmission. The Leprosy Post-Exposure Prophylaxis (LPEP) programme, currently ongoing in eight endemic countries, pilots the provision of single-dose rifampicin (SDR) to eligible contacts of leprosy patients. LPEP has developed a surveillance system including data collection, reporting and regular monitoring for every participating country. This system is still largely programme- specific to LPEP. To facilitate continuity after completion of the project phase and start-up in other interested countries, we aim at identifying the minimal set of data required to appropriately document contact tracing activities and SDR administration for leprosy control in a routine setting. We describe four indicators for the index case (plus four already routinely collected) and seven indicators for household/neighbour screening, and community surveys. We propose two generic forms to capture all relevant information required at field and district level to follow-up on individuals or data if needed, provide guidance on the sequence of tasks, provide quality control by listing key questions to assess SDR eligibility, and facilitate reporting. These generic forms have to be adapted to local requirements in terms of layout, language, and additional operational indicators.

Retrospective active case finding in Cambodia: An innovative approach to leprosy control in a low-endemic country

Currently, leprosy control relies on the clinical diagnosis of leprosy and the subsequent administration of multidrug therapy (MDT). However, many health workers are not familiar with the cardinal signs of leprosy, particularly in low-endemic settings including Cambodia. In response, a new approach to early diagnosis was developed in the country, namely retrospective active case finding (RACF) through small mobile teams. In the frame of RACF, previously diagnosed leprosy patients are traced and their contacts screened through “drives”.According to the available records, 984 of the 1,463 (67.3%) index patients diagnosed between 2001 and 2010 and registered in the national leprosy database were successfully traced in the period 2012–2015. Migration (8.4%), death (6.7%), operational issues (1.6%) and unidentified other issues (16.0%) were the main reasons for non-traceability. A total of 17,134 contacts of traced index patients (average: 2.2 household members and 15.2 neighbors) and another 7,469 contacts of the untraced index patients could be screened. Among them, 264 new leprosy patients were diagnosed. In the same period, 1,097 patients were diagnosed through the routine passive case detection system. No change was observed in the relation between the rate at which new patients were identified and the number of years since the diagnosis of the index patient. Similar to leprosy patients diagnosed through passive case detection, the leprosy patients detected through RACF were predominantly adult males. However, the fraction of PB leprosy patients was higher among the patients diagnosed through RACF, suggesting relatively earlier diagnosis.It appears that RACF is a feasible option and effective in detecting new leprosy patients among contacts of previously registered patients. However, a well-maintained national leprosy database is essential for successful contact tracing. Hence, passive case detection in the frame of routine leprosy surveillance is a precondition for efficient RACF as the two systems are mutually enhancing. Together, the two approaches may offer an interesting option for countries with low numbers of leprosy patients but evidence of ongoing transmission. The impact on leprosy transmission could be further increased by the administration of single dose rifampicin as post-exposure prophylaxis to eligible contacts.

Introducing leprosy post-exposure prophylaxis into the health systems of India, Nepal and Indonesia: a case study

BackgroundLeprosy has a wide range of clinical and socio-economic consequences. India, Indonesia and Nepal contribute significantly to the global leprosy burden. After integration, the health systems are pivotal in leprosy service delivery. The Leprosy Post Exposure Prophylaxis (LPEP) program is ongoing to investigate the feasibility of providing single dose rifampicin (SDR) as post-exposure prophylaxis (PEP) to the contacts of leprosy cases in various health systems. We aim to compare national leprosy control programs, and adapted LPEP strategies in India, Nepal and Indonesia. The purpose is to establish a baseline of the health system’s situation and document the subsequent adjustment of LPEP, which will provide the context for interpreting the LPEP results in future.MethodsThe study followed the multiple-case study design with single units of analysis. The data collection methods were direct observation, in-depth interviews and desk review. The study was divided into two phases, i.e. review of national leprosy programs and description of the LPEP program. The comparative analysis was performed using the WHO health system frameworks (2007).ResultsIn all countries leprosy services including contact tracing is integrated into the health systems. The LPEP program is fully integrated into the established national leprosy programs, with SDR and increased documentation, which need major additions to standard procedures. PEP administration was widely perceived as well manageable, but the additional LPEP data collection was reported to increase workload in the first year.ConclusionsThe findings of our study led to the recommendation that field-based leprosy research programs should keep health systems in focus. The national leprosy programs are diverse in terms of organizational hierarchy, human resource quantity and capacity. We conclude that PEP can be integrated into different health systems without major structural and personal changes, but provisions are necessary for the additional monitoring requirements.

Transporter-Mediated Hepatic Uptake Plays an Important Role in the Pharmacokinetics and Drug-Drug Interactions of Montelukast.

Montelukast, a leukotriene receptor antagonist commonly prescribed for treatment of asthma, is primarily metabolized by cytochrome P450 (CYP)2C8, and has been suggested as a probe substrate for investigating CYP2C8 activity in vivo. We evaluated the quantitative role of hepatic uptake transport in its pharmacokinetics and drug-drug interactions (DDIs). Montelukast was characterized with significant active uptake in human hepatocytes, and showed affinity towards organic anion transporting polypeptides (OATPs) in transfected cell systems. Single-dose rifampicin, an OATP inhibitor, decreased montelukast clearance in rats and monkeys. Clinical DDIs of montelukast were evaluated using physiologically based pharmacokinetic modeling; and simulation of the interactions with gemfibrozil-CYP2C8 and OATP1B1/1B3 inhibitor, clarithromycin-CYP3A and OATP1B1/1B3 inhibitor, and itraconazole-CYP3A inhibitor, implicated OATPs-CYP2C8-CYP2C8 interplay as the primary determinant of montelukast pharmacokinetics. In conclusion, hepatic uptake plays a key role in the pharmacokinetics of montelukast, which should be taken into account when interpreting clinical interactions.

Leprosy Post-Exposure Prophylaxis (LPEP) programme: study protocol for evaluating the feasibility and impact on case detection rates of contact tracing and single dose rifampicin

IntroductionThe reported number of new leprosy patients has barely changed in recent years. Thus, additional approaches or modifications to the current standard of passive case detection are needed to interrupt...

Negligible risk of inducing resistance in Mycobacterium tuberculosis with single-dose rifampicin as post-exposure prophylaxis for leprosy.

Post-exposure prophylaxis (PEP) for leprosy is administered as one single dose of rifampicin (SDR) to the contacts of newly diagnosed leprosy patients. SDR reduces the risk of developing leprosy among contacts by around 60 % in the first 2–3 years after receiving SDR. In countries where SDR is currently being implemented under routine programme conditions in defined areas, questions were raised by health authorities and professional bodies about the possible risk of inducing rifampicin resistance among the M. tuberculosis strains circulating in these areas. This issue has not been addressed in scientific literature to date. To produce an authoritative consensus statement about the risk that SDR would induce rifampicin-resistant tuberculosis, a meeting was convened with tuberculosis (TB) and leprosy experts. The experts carefully reviewed and discussed the available evidence regarding the mechanisms and risk factors for the development of (multi) drug-resistance in M. tuberculosis with a view to the special situation of the use of SDR as PEP for leprosy. They concluded that SDR given to contacts of leprosy patients, in the absence of symptoms of active TB, poses a negligible risk of generating resistance in M. tuberculosis in individuals and at the population level. Thus, the benefits of SDR prophylaxis in reducing the risk of developing leprosy in contacts of new leprosy patients far outweigh the risks of generating drug resistance in M. tuberculosis.Electronic supplementary materialThe online version of this article (doi:10.1186/s40249-016-0140-y) contains supplementary material, which is available to authorized users.

Leprosy is definitely not a disease of the past

In this review we present a synthesis of the current knowledge of leprosy based on the epidemiological studies and the latest data obtained in basic research and the strategies undertaken to fight out this pathology. The significant progress in the genomic study of the leprosy bacillus, and in understanding the basic mechanisms governing the individual susceptibility to the disease, together with the stagnation in the incidence of the new cases observed for ten years, represent focus of interest. If the efficiency of the recommended treatments is actually confirmed by a low relapse rate, however the drying up of new cases, which could be expected by reducing the infectiousness of the treated cases, is nonetheless slow in coming. Recent studies support the effectiveness of prophylaxis based on a single dose of rifampicin and/or a BCG vaccination of patient contacts. This could allow an increased reduction of the incidence of the disease. However, no official position validates such strategies. Because of an ambiguity in the expression of the objectives for managing the disease, i.e. « elimination of a disease considered as a public health problem », which should not to be confused with « eradication of the disease », which, in fact, has no relevance today, demobilization in fighting against leprosy is to be feared.

Clinical manifestations of leprosy after BCG vaccination: An observational study in Bangladesh

BackgroundAlthough BCG is used as a vaccine against tuberculosis, it also protects against leprosy. Previous evaluation over 18 years of an intervention of two doses BCG for 3536 household contacts of leprosy patients showed that 28 (23%) out of 122 contacts diagnosed with leprosy, developed symptoms 2–10 months after vaccination. This study describes contacts of leprosy patients in Bangladesh who developed leprosy within 12 weeks after receiving a single BCG dose. MethodsA cluster RCT in Bangladesh aims to study the effectiveness of the BCG vaccine versus BCG in combination with single dose rifampicin (SDR) given 2 to 3 months after BCG, in the prevention of leprosy among contacts of newly diagnosed leprosy patients. During the first 1,5 years of this ongoing trial we identified contacts who developed leprosy within the first 12 weeks after receiving BCG vaccination, the timeframe before SDR is given. ResultsWe identified 21 contacts who developed leprosy within 12 weeks after BCG vaccination among 5196 vaccinated contacts (0.40%). All 21 cases presented with paucibacillary (PB) leprosy, including children and adults. About half of these cases had previously received BCG vaccination as indicated by the presence of a BCG scar; 43% presented with signs of nerve function impairment and/or Type 1 (reversal) reaction, and 56% of the index patients had multibacillary (MB) leprosy. ConclusionAn unexpectedly high proportion of healthy contacts of leprosy patients presented with PB leprosy within 12 weeks after receiving BCG vaccination, possibly as a result of boosted cell-mediated immunity by homologues of Mycobacterium leprae antigens in BCG. Various immunological mechanisms could underlie this phenomenon, including an immune reconstitution inflammatory syndrome (IRIS). Further studies are required to determine whether BCG vaccination merely altered the incubation period or actually changed the course of the infection from self-limiting, subclinical infection to manifest disease.

Protecting people against leprosy: Chemoprophylaxis and immunoprophylaxis

Elimination of leprosy cannot be achieved by multidrug therapy alone, and new tools are needed to prevent leprosy. A randomized controlled trial with chemoprophylaxis for contacts of leprosy patients using a single dose of rifampicin (SDR) has shown an overall protective effect of approximately 60%, effective in the first 2 years after the intervention. When a contact who previously received bacillus Calmette-Guérin (BCG) vaccination also receives SDR, the protective effect is additive, approximating 80%. Vaccine trials have been conducted with BCG, often in combination with Mycobacterium leprae or related Mycobacterium vaccines as immunoprophylaxis for contacts of leprosy patients, with BCG giving the best results. Meta-analysis shows that the protective effect of BCG vaccination is larger in observational studies than in trials, 60% versus 41%, and is higher among contacts of leprosy patients than among the general population, 68% versus 53%. We believe that a future leprosy control strategy should include contact management, consisting of a contact survey, at which time preventive interventions could be added, such as chemoprophylaxis and immunoprophylaxis. Modeling studies have shown that both interventions will lower the incidence of leprosy in the population. Implementation studies of such contact-based strategy are now called for.

Role of contact tracing and prevention strategies in the interruption of leprosy transmission

The global prevalence of leprosy has declined from 5.2 million in the 1980 s to 200,000 today. However, the new case detection rate remains high: over the last 8 years, around 220,000-250,000 people have been diagnosed with leprosy each year. In June 2013, an international meeting was organised by the Novartis Foundation for Sustainable Development in Geneva, Switzerland,2 with the objective of discussing the feasibility of interrupting the transmission of leprosy. The group of physicians, epidemiologists and public health professionals concluded that a successful programme would require early diagnosis and prompt multidrug therapy (MDT) for all patients, tracing and post-exposure prophylaxis (PEP) for contacts of patients newly diagnosed with leprosy, improvements in diagnostic tools, as well as strict epidemiological surveillance and response systems to monitor progress. As a follow-up, a second expert group meeting was convened by the Novartis Foundation in January 2014 in Zurich, Switzerland, with the objective of reviewing the evidence for chemoprophylaxis in contacts and high-risk communities. The meeting also considered the definitions of 'contacts' and 'contact tracing', discussed alternative prophylaxis regimens, preliminary findings of operational pilot projects on PEP in Indonesia, as well as the development of diagnostic tools, and identified the priority questions for operational research in leprosy transmission. The meeting outlined how contact tracing and chemoprophylaxis programmes can be implemented to interrupt leprosy transmission. The expert panel reached the following conclusions: Chemoprophylaxis with single-dose rifampicin (SDR) is efficacious in reducing the risk of developing leprosy, although the protective effect appears to be smaller in contacts closer to the index patient than in more distant contacts.3 SDR can be targeted to contacts or implemented as community mass prophylaxis in certain circumstances; the preferred approach depends on local factors, such as the case detection rate, the level of community stigma against leprosy, and the degree of access to healthcare for patients and contacts. Alternative prophylaxis regimens and the role of post-exposure immunoprophylaxis need to be further investigated. Contact tracing combined with PEP across very diverse settings offers protection rates similar to those reported in controlled trials. For high-incidence pockets ('hotspots') or remote or confined high-incidence populations ('hotpops'), blanket administration of PEP may be a better option. Implementation of contact-tracing programmes is feasible and cost-effective, particularly in high-risk groups, but it should be integrated into local healthcare services to ensure their long-term sustainability. Funding and support must be maintained after an initial pilot has finished. New programmes for contact tracing need effective surveillance systems to enable appropriate follow-up and outcome evaluation. The Novartis Foundation and Netherlands Leprosy Relief (NLR) are currently developing and implementing a large international programme to demonstrate the feasibility, acceptability, cost-effectiveness and real-world efficacy of PEP as a strategy to interrupt leprosy transmission, in six pilot projects in Asia, Africa and South America. These new pilot projects will be developed together with the local health authorities, healthcare workers, communities and patients, in order to create local ownership from the outset. The pilots should aim to be scalable and sustainable, and should therefore include an objective outcome assessment. Local ownership ensures that locally appropriate language and definitions of contacts are used in each of the pilots. A test to identify subclinical disease and distinguish M. leprae exposure from infection would facilitate early and appropriate therapy (with PEP or MDT). The identification and validation of new, sensitive biomarkers for M. leprae infection and exposure may allow better targeting of PEP to those contacts at highest risk of developing leprosy.

The combined effect of chemoprophylaxis with single dose rifampicin and immunoprophylaxis with BCG to prevent leprosy in contacts of newly diagnosed leprosy cases: a cluster randomized controlled trial (MALTALEP study)

BackgroundDespite almost 30 years of effective chemotherapy with MDT, the global new case detection rate of leprosy has remained quite constant over the past years. New tools and methodologies are necessary to interrupt the transmission of M. leprae. Single-dose rifampicin (SDR) has been shown to prevent 57% of incident cases of leprosy in the first two years, when given to contacts of newly diagnosed cases. Immunization of contacts with BCG has been less well documented, but appears to have a preventive effect lasting up to 9 years. However, one major disadvantage is the occurrence of excess cases within the first year after immunization. The objective of this study is to examine the effect of chemoprophylaxis with SDR and immunoprophylaxis with BCG on the clinical outcome as well as on host immune responses and gene expression profiles in contacts of newly diagnosed leprosy patients. We hypothesize that the effects of both interventions may be complementary, causing the combined preventive outcome to be significant and long-lasting.Methods/designThrough a cluster randomized controlled trial we compare immunization with BCG alone with BCG plus SDR in contacts of new leprosy cases. Contact groups of around 15 persons will be established for each of the 1300 leprosy patients included in the trial, resulting in approximately 20,000 contacts in total. BCG will be administered to the intervention group followed by SDR, 2 months later. The control group will receive BCG only. In total 10,000 contacts will be included in both intervention arms over a 2-year period. Follow-up will take place one year as well as two years after intake. The primary outcome is the occurrence of clinical leprosy within two years. Simultaneously with vaccination and SDR, blood samples for in vitro analyses will be obtained from 300 contacts participating in the trial to determine the effect of these chemo- and immunoprophylactic interventions on immune and genetic host parameters.DiscussionCombined chemoprophylaxis and immunoprophylaxis is potentially a very powerful and innovative tool aimed at contacts of leprosy patients that could reduce the transmission of M. leprae markedly. The trial intends to substantiate this potential preventive effect. Evaluation of immune and genetic biomarker profiles will allow identification of pathogenic versus (BCG-induced) protective host biomarkers and could lead to effective prophylactic interventions for leprosy using optimized tools for identification of individuals who are most at risk of developing disease.Trial registrationNetherlands Trial Register: NTR3087

Patient-related factors predicting the effectiveness of rifampicin chemoprophylaxis in contacts: 6 year follow up of the COLEP cohort in Bangladesh

The COLEP trial in Bangladesh showed a 57% reduction in leprosy incidence among contacts of newly diagnosed patients in the first 2 years after chemoprophylaxis with single dose rifampicin (SDR). We assessed the impact of this intervention after 6 years and identified characteristics of the leprosy index patients predicting the effectiveness of this intervention. The cohort of 1037 patients and their 28 092 contacts that participated in the randomised placebo controlled field trial with single dose rifampicin was followed for 6 years. The leprosy status of contacts was established at 2, 4 and 6 years after the intervention. We assessed the association between characteristics of the index leprosy patients and the development of clinical leprosy among their contacts using logistic regression. The protective effect of SDR was seen only in the first 2 years, with no additional effect after 4 and 6 years. However, the total impact of the intervention was still statistically significant (P = 0.025) after 6 years and no excess cases were observed in the SDR arm at a later stage. The intervention prevented leprosy in contacts that actually received SDR, but did not offer protection to members of the same contact group who did not take chemoprophylaxis. The intervention was most effective in contact groups of female index patients, an enhanced effect was also observed in contact groups of patients belonging to a cluster of two or more leprosy patients at intake as well. These easy to recognise patient characteristics indicate a possible enhanced risk of transmission of Mycobacterium leprae to contacts in the vicinity of patients and are useful for deciding about preventive measures, such as early detection or chemoprophylaxis.

Clinical, bacteriological and histopathological study of 62 referral relapse cases between Jan 2004 and Dec 2009 at the Foundation for Medical Research, Mumbai

Sixty two patients with relapsed leprosy seen between Jan 2004 and Dec 2009 were studied using clinical, bacteriological and histopathological parameters. The findings thus obtained were correlated to parameters such as trend and source of referral, clinical characteristics at diagnosis, treatment received, other events during or after RFT and duration between cessation of treatment and relapse. Referrals per year have doubled since 2006. Most patients were referred by NGOs (58%), followed by Govt. hospitals (16%) and then by GPs (25%); 76% had received one of the WHO - MDT regimens including 16 treated with 24 months or more MB - MDT, 23 with 12 months MB - MDT and eight with 6 months PB - MDT. Of the remaining 14 cases, four had received DDS mono-therapy, seven had single dose of Rifampicin, Ofloxacin and Minocycline (ROM) and four Rifampicin and Ofloxacin (RO) daily for 28 days. The average incubation time of relapse, defined as duration between cessation of treatment and relapse was (SD) + 6-4 years. 59% of patients had positive slit skin smears on relapse. Relapse for the second time occurred in six BL cases including five from group 2 and one RO treated patient and 11/23 cases from group 2 conferred to BT-BB leprosy. Clinical features at diagnosis and on relapse were comparable in 47% of cases. All leprosy patients, regardless of their type and MDT regime, carry 'risk of relapse'. A shorter treatment duration reduces the incubation time to relapse. In group 2 (treated with 12 months MB-MDT regime) 11/23 were BT-BB cases and 5/23 (21%) were relapse for the second time, which further supports our earlier documented findings and maybe the efficacy of WHO-MDT regime is poor in a small subset of patients.

Acceptability of chemoprophylaxis for household contacts of leprosy patients in Bangladesh: a qualitative study

Chemoprophylaxis with single dose rifampicin is a promising intervention to prevent leprosy in close contacts of patients. However, application in control programmes often requires disclosure of the leprosy diagnosis, which is still a stigmatised disease in many countries. Promoting control and treatment of stigmatised diseases without contributing towards stigma of the individuals involved can be very difficult. The objective of this study was to assess the social acceptability of disclosure of the diagnosis and the attitude towards taking prophylactic medicines in a leprosy endemic area in Bangladesh. Qualitative study through focus group discussions with 136 healthy men and women from different age groups and religions, coming from two rural villages and an urban area in northwest Bangladesh, and 14 health workers with extensive experience with leprosy patients. The participants would not object to disclosure of the diagnosis to household members and nearby family if they were diagnosed with leprosy. However, many participants were not willing to share this information with their neighbours and other social contacts due to stigma of the disease. All healthy participants were willing to take chemoprophylaxis if any of their close contacts were diagnosed with leprosy, even after explaining that full protection against leprosy was not guaranteed. It can be concluded that chemoprophylaxis for household contacts of leprosy patients is an effective and socially acceptable addition to the current leprosy control programme. Chemoprophylaxis for other categories of contacts likely to benefit would only be feasible, without disclosure of patient information, if given in the form of mass campaigns for the whole population in the area.

Cost-effectiveness of a chemoprophylactic intervention with single dose rifampicin in contacts of new leprosy patients.

BackgroundWith 249,007 new leprosy patients detected globally in 2008, it remains necessary to develop new and effective interventions to interrupt the transmission of M. leprae. We assessed the economic benefits of single dose rifampicin (SDR) for contacts as chemoprophylactic intervention in the control of leprosy.MethodsWe conducted a single centre, double blind, cluster randomised, placebo controlled trial in northwest Bangladesh between 2002 and 2007, including 21,711 close contacts of 1,037 patients with newly diagnosed leprosy. We gave a single dose of rifampicin or placebo to close contacts, with follow-up for four years. The main outcome measure was the development of clinical leprosy. We assessed the cost effectiveness by calculating the incremental cost effectiveness ratio (ICER) between the standard multidrug therapy (MDT) program with the additional chemoprophylaxis intervention versus the standard MDT program only. The ICER was expressed in US dollars per prevented leprosy case.FindingsChemoprophylaxis with SDR for preventing leprosy among contacts of leprosy patients is cost-effective at all contact levels and thereby a cost-effective prevention strategy. In total, $6,009 incremental cost was invested and 38 incremental leprosy cases were prevented, resulting in an ICER of $158 per one additional prevented leprosy case. It was the most cost-effective in neighbours of neighbours and social contacts (ICER $214), slightly less cost-effective in next door neighbours (ICER $497) and least cost-effective among household contacts (ICER $856).ConclusionChemoprophylaxis with single dose rifampicin given to contacts of newly diagnosed leprosy patients is a cost-effective intervention strategy. Implementation studies are necessary to establish whether this intervention is acceptable and feasible in other leprosy endemic areas of the world.

Chemoprophylaxis in contacts of patients with leprosy: systematic review and meta-analysis

To identify and summarize randomized clinical trials (RCTs) that assessed the effectiveness of chemoprophylaxis to prevent leprosy in contacts of patients newly diagnosed with the disease. All studies were extracted from Medline (PubMed 1966 to November 2008), the Cochrane Controlled Trials Register (number 3 2008), LILACS (1982 to November 2008), and Scirus (November 2008). Manual searches and searches of crossed references of assessed articles were also done. RCTs' risk of bias was assessed according to the methodology proposed by the Cochrane Collaboration. The main outcome measure was diagnosis of leprosy (secondary cases) in contacts of patients with the disease (primary cases). The search identified 320 references, from which 7 RCTs with a total of 66 311 participants were included and evaluated. The combined results from the RCTs favored chemoprophylaxis to placebo with 2-4 years of follow-up (6 RCTs, 66 107 participants, relative risk (RR) 0.59, 95% confidence interval (CI) 0.50-0.70, I(2) = 0 (I(2) describes percent total variation across studies caused by heterogeneity)). Single-dose rifampicin (21 711 participants, RR 0.43, 95% CI 0.28-0.67, number needed to treat 285), dapsone once or twice weekly for at least 2 years (3 RCTs, 43 137 participants, RR 0.60, 95% CI 0.48-0.76, I(2) = 0), and acedapsone every 10 weeks for 7 months (2 RCTs, 1 259 participants, RR 0.49, 95% CI 0.33-0.72, I(2) = 0) were significantly superior to placebo in preventing secondary cases of leprosy. Chemoprophylaxis is effective in lowering the incidence of leprosy in contacts of patients diagnosed with the disease.

Altered integrity and decreased expression of hepatocyte tight junctions in rifampicin-induced cholestasis in mice

Rifampicin is a well-known hepatotoxicant, but little is known about the mechanism of rifampicin-induced hepatotoxicity. The aim of this study was to characterize the expression and localization of hepatocyte tight junctions in rifampicin-induced cholestasis in mice. Cholestasis was induced by administration of rifampicin (200 mg/kg) for 7 consecutive days or treatment with a single dose of rifampicin (200 mg/kg) by gastric intubation. The expression of mRNA for hepatic zonula occludens (ZO)-1, ZO-2, ZO-3, occludin and claudin-1 was determined using RT-PCR. Localization of ZO-1 and occludin was detected using immunofluorescence. Results showed that there was an 82-fold increase in the conjugated bilirubin in serum in rifampicin-treated mice. In addition, an 8-fold increase in total bile acid in serum was observed after a seven-day administration of rifampicin. The integrity of hepatocyte ZO-1 and occludin was altered by a seven-day administration of rifampicin. Importantly, the integrity and intensity of hepatocyte tight junctions were altered as early as 30 min after a single dose of rifampicin. The expression of hepatic ZO-1 and ZO-2 mRNA was significantly decreased, beginning as early as 30 min and remaining a lower level 12 h after a single dose of rifampicin. Taken together, these results suggest that the altered integrity and internalization of hepatocyte tight junctions are associated with rifampicin-induced cholestasis.

Effectiveness of single dose rifampicin in preventing leprosy in close contacts of patients with newly diagnosed leprosy: cluster randomised controlled trial

Effectiveness of single dose rifampicin in preventing leprosy in close contacts of patients with newly diagnosed leprosy: cluster randomised controlled trial