A single synthetic lipid antigen for improved serological diagnosis of Buruli ulcer.

SETTING: The diagnosis of Buruli ulcer (BU) is frequently made by experienced health workers in rural regions. This leads to long turnaround times to confirm the diagnosis as it requires specialised laboratory infrastructure to perform confirmatory testing. BACKGROUND: Given the lack of success with protein antigens to detect BU in human sera, the aim of this study was to evaluate a range of single synthetic lipid antigens using an enzyme-linked immunosorbent assay (ELISA). The ELISA system used was initially developed to detect TB using single synthetic lipid antigens. METHODS: Thirty polymerase chain reaction (PCR) positive BU samples and 30 PCR-negative healthy contact samples collected from Asante Akim North and Ahafo Ano North Districts, Ghana, that are endemic for BU between 2013 and 2016 were used to evaluate the synthetic lipid antigen ELISA. A Quantikine ELISA was also conducted on a randomly blinded sub-set of 30 samples. RESULTS: The synthetic lipid ELISA evaluated here outperforms all other ELISA tests using protein antigens to detect BU to date and has shown potential as a fast (2 h) test for BU which may be adapted for use at the point of care. A sensitivity of 63% and specificity of 80% was observed for 30 BU-positive and 30 BU-negative samples, with significantly reduced interleukin-8 (IL-8) levels in a subset of patients with BU. CONCLUSION: A single lipid was shown for the first time to have the ability to distinguish between PCR-positive BU and negative sera using ELISA. The low lipid antibody load detected may be a result of immune suppression caused by the presence of mycolactone in patients with BU, given that levels of IL-8 were significantly reduced in patients with BU compared to the control serum samples.

Cost minimization analysis of line probe assay for detection of multidrug-resistant tuberculosis in Arkhangelsk region of Russian Federation.

BACKGROUND: The development of new diagnostic tools allows for faster detection of both tuberculosis (TB) and multidrug-resistant (MDR) TB and should lead to reduced transmission by earlier initiation of anti TB therapy. The research conducted in the Arkhangelsk region of the Russian Federation in 2012-14 included economic evaluation of Line Probe Assay (LPA) implementation in MDR-TB diagnostics compared to existing culture-based diagnostics of Löwenstein Jensen (LJ) and BacTAlert. Clinical superiority of LPA was demonstrated and results were reported elsewhere. STUDY AIM: The PROVE-IT Russia study aimed to report the outcomes of the cost minimization analysis. METHODS: Costs of LPA-based diagnostic algorithm (smear positive (SSm+) and for smear negative (SSm-) culture confirmed TB patients by Bactec MGIT or LJ were compared with conventional culture-based algorithm (LJ-for SSm- and SSm+ patients and BacTAlert-for SSm+ patients). Cost minimization analysis was conducted from the healthcare system, patient and societal perspectives and included the direct and indirect costs to the healthcare system (microscopy and drug susceptibility test (DST), hospitalization, medications obtained from electronic medical records) and non-hospital direct costs (patient's travel cost, additional expenses associated with hospitalization, supplementary medicine and food) collected at the baseline and two subsequent interviews using the WHO-approved questionnaire. RESULTS: Over the period of treatment the LPA-based diagnostic corresponded to lesser direct and indirect costs comparing to the alternative algorithms. For SSm+ LPA-based diagnostics resulted in the costs 4.5 times less (808.21 US$) than LJ (3593.81 US$) and 2.5 times less than BacTAlert liquid culture (2009.61 US$). For SSm- LPA in combination with Bactec MGIT (1480.75 US$) vs LJ (1785.83 US$) showed the highest cost minimization compared to LJ (2566.09 US$). One-way sensitivity analyses of the key parameters and threshold analyses were conducted and demonstrated that the results were robust to variations in the cost of hospitalization, medications and length of stay. CONCLUSION: From the perspective of Russian Federation healthcare system, TB diagnostic algorithms incorporating LPA method proved to be both more clinically effective and less expensive due to reduction in the number of hospital days to the correct MDR-TB diagnosis and treatment initiation. LPA diagnostics comparing conventional culture diagnostic algorithm MDR-TB was a cost minimizing strategy for both patients and healthcare system.

The Ethiopian initiative to build sustainable capacity for operational research: overview and lessons learned.

SETTING: Programme-based operational research is instrumental for the enhancement of tuberculosis (TB) control. In 2012, the Ethiopian Federal Ministry of Health launched an initiative for capacity building in operational research (OR). OBJECTIVE: To develop sustainable capacity for OR in Ethiopia in a multiyear initiative. DESIGN: The initiative was developed in collaboration with regional, national and international experts. Teams representing regions in Ethiopia conducted OR addressing national and regional priorities. To make use of local expertise and increase sustainability, a domestic mentor training programme was included. Existing capacity was enhanced through a competitive grant scheme providing TB researchers with financial and technical support. The Ethiopian Tuberculosis Research Advisory Committee was also supported in its functions. Regional ethics review bodies were strengthened or established where they did not exist. RESULTS: Fifty-two people were trained and conducted 13 OR projects, of which six have been published to date. In addition, eight protocols were supported through grants. Ethics review bodies were strengthened in all regions. CONCLUSION: The initiative trained participants from all regions and succeeded in the completion of all stages of the OR process. The success of the programme can be attributed to the team approach, 'learning while doing', integrated mentorship programme and strong national ownership.

Contexte : La recherche opérationnelle programmatique joue un rôle majeur dans la lutte contre la tuberculose (TB). En 2012, le ministère éthiopien de la santé a lancé une initiative de renforcement des capacités en recherche opérationnelle (OR).Objectif : Développer des capacités pérennes d'OR en Ethiopie dans le cadre d'une initiative s'étalant sur plusieurs années.Schéma : L'initiative a été élaborée en collaboration avec des experts régionaux, nationaux et internationaux. Des équipes représentant les régions d'Ethiopie ont réalisé une OR relative aux priorités nationales et régionales. Un programme de formation de mentors domestiques a été inclus afin d'exploiter l'expertise locale et d'accroitre la pérennité. La capacité existante a été renforcée grâce à un financement compétitif offrant aux chercheurs du domaine de la TB un soutien financier et technique. Le fonctionnement du comité de concertation éthiopien sur la recherche relative à la TB a également bénéficié d'un soutien. Les comités d'éthique régionaux ont été renforcés ou créés lorsqu'ils n'existaient pas.Résultats : Cinquante-deux personnes ont été formées et ont réalisé 13 projets d'OR, dont six ont été publiés à ce jour. De plus, huit protocoles ont été soutenus par des subventions. Les comités d'éthique ont été renforcés dans toutes les régions.Conclusion: L'initiative a formé des participants de toutes les régions et ceux-ci ont terminé avec succès toutes les étapes du processus d'OR. Le succès de ce programme peut être attribué à une approche sous forme de travail d'équipe, à un apprentissage sur le tas, au programme intégré de mentors et à une forte appropriation nationale.

Marco de referencia: La práctica de investigación operativa dentro del marco programático es importante en el fortalecimiento del control de la tuberculosis (TB). En el 2012, el Ministerio Federal de Salud de Etiopía puso en marcha una iniciativa encaminada a crear capacidad de investigación operativa (OR).Objetivo: Desarrollar capacidad sostenible de OR en el país mediante una iniciativa plurianual.Método: La iniciativa se formuló en cooperación con expertos regionales, nacionales e internacionales. Varios equipos, en representación de las regiones de Etiopía, llevaron a cabo proyectos de OR que respondían a las prioridades nacionales y regionales. Con el propósito de aprovechar las competencias locales y mejorar la sostenibilidad se incorporó al proyecto un programa interno de capacitación de tutores. Se reforzó la capacidad existente mediante un plan de subvenciones otorgadas por concurso y destinado a suministrar ayuda económica y técnica a los investigadores en el campo de la TB. Asimismo, se prestó apoyo al funcionamiento del Comité Asesor de la Investigación sobre TB en Etiopía. Se reforzaron los comités de ética existentes y donde no existían se crearon nuevos comités.Resultados: Se capacitó a 52 personas y se llevaron a cabo 13 proyectos de OR, de los cuales seis han publicado sus resultados hasta la fecha. Se financiaron además ocho protocolos por conducto de las subvenciones. Se reforzaron los comités de ética en todas las regiones.Conclusión: Gracias a esta iniciativa se capacitó a los participantes provenientes de todas las regiones y se logró la compleción de todas las etapas del proceso de OR. El éxito del programa se puede atribuir a la estrategia de equipo, el aprendizaje en la acción, la integración del programa de tutoría y a una decidida apropiación nacional de la iniciativa.

Resistance to first-line tuberculosis drugs in three cities of Nigeria.

OBJECTIVES: To determine the levels of resistance to first-line tuberculosis drugs in three cities in three geopolitical zones in Nigeria. METHODS: A total of 527 smear-positive sputum samples from Abuja, Ibadan and Nnewi were cultured on BACTEC- MGIT 960. Drug susceptibility tests (DST) for streptomycin, isoniazid, rifampicin and ethambutol were performed on 428 culture-positive samples on BACTEC-MGIT960. RESULTS: Eight per cent of the specimens cultured were multi-drug-resistant Mycobacterium tuberculosis (MDR-TB) with varying levels of resistance to individual and multiple first-line drugs. MDR was strongly associated with previous treatment: 5% of new and 19% of previously treated patients had MDR-TB (OR 4.1 (95% CI 1.9-8.8), P = 0.001) and with young adult age: 63% of patients with and 38% without MDR-TB were 25-34 years old (P = 0.01). HIV status was documented in 71%. There was no association between MDR-TB and HIV coinfection (P = 0.9) and gender (P > 0.2 for both). CONCLUSIONS: MDR-TB is an emerging problem in Nigeria. Developing good quality drug susceptibility test facilities, routine monitoring of drug susceptibility and improved health systems for the delivery of and adherence to first- and second-line treatment are imperative to solve this problem.

Married to M. tuberculosis: risk of infection and disease in spouses of smear-positive tuberculosis patients.

OBJECTIVES: To quantify the risk of infection and disease in spouses of tuberculosis patients and the extent to which intervention could reduce the risk in this highly exposed group. METHODS: We compared HIV prevalence, TB prevalence and incidence and tuberculin skin test (TST) results in spouses of TB patients and community controls. HIV-positive spouses were offered isoniazid preventive therapy (IPT), and TST was repeated at 6, 12 and 24 months. RESULTS: We recruited 148 spouses of smear-positive patients ascertained prospectively and 3% had active TB. We identified 203 spouses of previously diagnosed smear-positive patients, 11 had already had TB, and the rate of TB was 2.4 per 100 person years(py) over 2 years (95% CI 1.15-5.09). 116 were found alive and recruited. HIV prevalence was 37% and 39% in the prospective and retrospective spouse groups and 17% in controls. TST was ≥10 mm in 80% of HIV negative and in 57% of HIV-positive spouses ascertained retrospectively; 74% HIV negative and 62% HIV-positive spouses ascertained prospectively, and 48% HIV negative and 26% HIV-positive community controls. Of 54 HIV-positive spouses, 18 completed 6-month IPT. At 2 year follow-up, 87% of surviving spouses had TST ≥10 mm and the rate of TB was 1.1 per 100 py (95% CI 0.34-3.29). CONCLUSIONS: Spouses are a high-risk group who should be screened for HIV and active TB. TST prevalence was already high by the time the spouses were approached but further infections were seen to occur. Uptake and adherence to IPT was disappointing, lessening the impact of short-duration therapy.

Simple measures are as effective as invasive techniques in the diagnosis of pulmonary tuberculosis in Malawi.

SETTING: Detection of smear-positive pulmonary tuberculosis (PTB) cases is vital for tuberculosis (TB) control. Methods to augment sputum collection are available, but their additional benefit is uncertain in resource-limited settings. OBJECTIVE: To compare the diagnostic yields using five methods to obtain sputum from adults diagnosed with smear-negative PTB in Malawi. DESIGN: Self-expectorated sputum was collected under supervision for microscopy and mycobacterial culture in the study laboratory. Confirmed smear-negative patients provided physiotherapy-assisted sputum and induced sputum, followed the next morning by gastric washing and bronchoalveolar lavage (BAL) samples. RESULTS: A total of 150 patients diagnosed with smear-negative PTB by the hospital service were screened; 39 (26%) were smear-positive from supervised self-expectorated sputum examined in the study laboratory. The remaining 111 confirmed smear-negative patients were enrolled in the study; 89% were human immunodeficiency virus positive. Seven additional smear-positive cases were diagnosed using the augmented sputum collection techniques. No differences were observed in the numbers of cases detected using the different methods. Of the 46 smear-positive cases, 44 (95.6%) could be detected from self-expectorated and physiotherapy-assisted samples. CONCLUSIONS: For countries such as Malawi, the best use of limited resources to detect smear-positive PTB cases would be to improve the quality of self-expectorated sputum collection and microscopy. The additional diagnostic yield using BAL after induced sputum is limited.

Time delays between patient and laboratory selectively affect accuracy of helminth diagnosis.

Studies of intestinal helminth infections are influenced by the constraints of sample collection, as identification of helminth ova in stools is affected by the time since evacuation from the host. Different methods may be required to optimise diagnostic sensitivity under different study conditions. In the context of studies in rural Malawi, we collected stool samples with different time delays from production by subjects to sample collection by field staff, to examination in the laboratory. Stools were processed by Kato-Katz (KK) or formol-ether concentration (FEC) methods. Hookworm and Schistosoma mansoni were the most common helminths identified. The prevalence of hookworm was higher with KK (270/988, 27%) than with FEC (191/988, 19%). Comparison was made between the results from the two methods according to the timing of the processing steps. Delays in processing did not affect retrieval of S. mansoni. A decrease in sensitivity of almost 50% for detection of hookworm was observed with either method when preservation/refrigeration was delayed by more than 3h. A delay of 1 day from refrigeration or preservation to laboratory processing also reduced the sensitivity for hookworm by 50% for both methods. Care must be taken in studies of multiple helminth infections owing to the selective reduction of hookworm ova during transport. This is particularly critical when samples are not preserved, even over short periods of time, and even with formalin preservation.