Medicine
Permanent URI for this communityhttp://repository.kln.ac.lk/handle/123456789/12
This repository contains the published and unpublished research of the Faculty of Medicine by the staff members of the faculty
Browse
8 results
Search Results
Item Risk factor analysis of cutaneous leishmaniasis in Sri Lanka through a nationwide survey(American Society of Tropical Medicine and Hygiene, 2024) Dewasurendra, R.; Samaranayake, N.; Silva, H.; Manamperi, N.; Senerath, U.; Senanayake, S.; De Silva, N.; Karunanayake, P.; Zhou, G.; Karunaweera, N.Leishmaniasis in Sri Lanka was first reported in the early 1990s. Cutaneous leishmaniasis (CL) cases have markedly increased in recent years, demanding due attention from health authorities. The spatial distribution of CL is not homogeneous. This case-control study investigated factors that may contribute to this heterogeneous distribution through a nationwide study. Information on sociodemographic, economic, and environmental characteristics was collected from study participants (cases, n = 303; controls, n = 2,762). All individuals were followed up for 3 years, and signs of CL or associated complications were recorded. Differences in possible risk factors between cases and controls were analyzed. Individuals <18 years old, electricity supply, spending >2 hours outdoors, visiting jungles/water bodies, and living near CL patients were identified as risk factors. Household members of 1.3% of cases, 2.3% of controls residing within a perimeter of 500 m from a patient, and 0.8% of controls living beyond 2 km from a case developed CL. Thus, CL in Sri Lanka appears intertwined with living environment and host behavior. Common environmental factors may be responsible for the higher risk of CL in individuals living in close proximity to CL patients. This may at least partly explain the clustering of CL cases in selected areas of the country.Item The use of recombinant K39, KMP11, and crude antigen-based indirect ELISA as a serological diagnostic tool and a measure of exposure for cutaneous leishmaniasis in Sri Lanka(Springer International, 2024) Karunathilake, C.; Alles, N.; Dewasurendra, R.; Weerasinghe, I.; Chandrasiri, N.; Piyasiri, S.B.; Samaranayake, N.; Silva, H.; Manamperi, N.; Karunaweera, N.Cutaneous leishmaniasis (CL) in Sri Lanka is caused by Leishmania donovani, a parasite widely known to cause visceral leishmaniasis. Despite the fact that CL is not generally believed to elicit serological immune responses, recent studies show the presence of antibody responses against this atypical form of CL. This study assesses the potential of using recombinant K39 (rK39), KMP11, and crude parasite antigen-based indirect ELISAs as serological diagnostic tools and measures of exposure for CL in Sri Lanka. The study used serum samples from confirmed CL patients (n = 266) and apparently healthy individuals from endemic settings (n = 411). Serum samples from individuals residing in non-endemic areas were used as negative controls. In-house indirect ELISAs were optimized and validated for recombinant antigens. Previously validated crude parasite extract-based indirect ELISA was performed for comparison. The statistical analyses were performed using SPSS v26.0. The rK39 (sensitivity = 71.2%, specificity = 64%) and KMP11 (sensitivity = 79.2%, specificity = 71.4%) based indirect ELISA were shown to be less suitable for the diagnosis of CL, while crude parasite extract-based indirect ELISA (sensitivity = 82.4%, specificity = 85.7%) might be a better method of diagnosis. All 03 ELISAs seemed to be good methods as measures of exposure since correlations were observed between the seropositivity of all 03 ELISAs (rK39: p = 0.037, KMP11: p = 0.007, CrudeAg: p = 0.000) with provincial case incidences. The findings will be important in identifying the disease hotspots in order to design the control measures for CL induced by L. donovani in Sri Lanka.Item Assessment of knowledge and perceptions on leishmaniasis: An island-wide study in Sri Lanka(Public Library of Science, 2022) Dewasurendra, R.; Silva, H.; Samaranayake, N.; Manamperi, N.; de Silva, N.; Karunanayake, P.; Senarath, U.; Senanayake, S.; Zhou, G.; Karunaweera, N.Cutaneous leishmaniasis (CL) is a notifiable disease in Sri Lanka with increasing case numbers reported from every part of the country. In addition to disease treatment and vector control measures, knowledge and perceptions in a community are key contributors to a successful intervention program. An island-wide survey was carried out to assess the knowledge and perceptions regarding CL across the island, with 252 confirmed CL cases and 2,608 controls. Data was collected by trained personnel, using a pre-tested Case Reporting Form (CRF). Although the percentage who referred to CL by its correct name was low (1.4%), majority stated that it is a fly induced skin disease (79.1%). Knowledge on the symptoms, curability and the name of the vector was high in these communities, but specific knowledge on vector breeding places, biting times and preventive methods were poor. The patients were more knowledgeable when compared to the controls. Differences in the level of knowledge could be identified according to the level of education of the participants as well as across the different areas of the country. The main source of information was through the healthcare system, but the involvement of media in educating the communities on the disease was minimal. While this study population was unaccustomed to the use of repellants or sprays, the use of bed nets was high (77.7% of the participants) in this study population. Although misconceptions and incorrect practices are rare in Sri Lankan communities, promoting health education programs which may improve disease awareness and knowledge on vector and its control will further strengthen the control and prevention strategies.Item Spatial epidemiologic trends and hotspots of leishmaniasis, Sri Lanka, 2001-2018(Centers for Disease Control and Prevention (CDC), 2020) Karunaweera, N.D.; Ginige, S.; Senanayake, S.; Silva, H.; Manamperi, N.; Samaranayake, N.; Siriwardana, Y.; Gamage, D.; Senerath, U.; Zhou, G.;ABSTRACT: Leishmaniasis, a neglected tropical disease, is on the decline in South Asia. However, cases of cutaneous leishmaniasis have risen in Sri Lanka since 2001, and the lack of in-depth research on its epidemiologic characteristics hampers control efforts. We analyzed data collected from patients with cutaneous leishmaniasis in Sri Lanka during 2001-2018 to study temporal and geographic trends and identify and monitor disease hotspots. We noted a progression in case rates, including a sharp rise in 2018, showing temporal expansion of disease-prevalent areas and 2 persistent hotspots. The northern hotspot shifted and shrank over time, but the southern hotspot progressively expanded and remained spatially static. In addition, we noted regional incidence differences for age and sex. We provide evidence of temporally progressive and spatially expanding incidence of leishmaniasis in Sri Lanka with distinct geographic patterns and disease hotspots, signaling an urgent need for effective disease control interventions. KEYWORDS: Asia; Indian subcontinent; Leishmania donovani; Sri Lanka; cutaneous leishmaniasis; dermatological pathologies; epidemiology; infectious diseases; leishmaniasis; parasites; protozoa; skin lesions; vector-borne infections.Item Spatiotemporal distribution of cutaneous leishmaniasis in Sri Lanka and future case burden estimates(Public Library of Science, 2021) Karunaweera, N.D.; Senanayake, S.; Ginige, S.; Silva, H.; Manamperi, N.; Samaranayake, N.; Dewasurendra, R.; Karunanayake, P.; Gamage, D.; de Silva, N.; Senarath, U.; Zhou, G.BACKGROUND: Leishmaniasis is a neglected tropical vector-borne disease, which is on the rise in Sri Lanka. Spatiotemporal and risk factor analyses are useful for understanding transmission dynamics, spatial clustering and predicting future disease distribution and trends to facilitate effective infection control. METHODS: The nationwide clinically confirmed cutaneous leishmaniasis and climatic data were collected from 2001 to 2019. Hierarchical clustering and spatiotemporal cross-correlation analysis were used to measure the region-wide and local (between neighboring districts) synchrony of transmission. A mixed spatiotemporal regression-autoregression model was built to study the effects of climatic, neighboring-district dispersal, and infection carryover variables on leishmaniasis dynamics and spatial distribution. Same model without climatic variables was used to predict the future distribution and trends of leishmaniasis cases in Sri Lanka. RESULTS: A total of 19,361 clinically confirmed leishmaniasis cases have been reported in Sri Lanka from 2001-2019. There were three phases identified: low-transmission phase (2001-2010), parasite population buildup phase (2011-2017), and outbreak phase (2018-2019). Spatially, the districts were divided into three groups based on similarity in temporal dynamics. The global mean correlation among district incidence dynamics was 0.30 (95% CI 0.25-0.35), and the localized mean correlation between neighboring districts was 0.58 (95% CI 0.42-0.73). Risk analysis for the seven districts with the highest incidence rates indicated that precipitation, neighboring-district effect, and infection carryover effect exhibited significant correlation with district-level incidence dynamics. Model-predicted incidence dynamics and case distribution matched well with observed results, except for the outbreak in 2018. The model-predicted 2020 case number is about 5,400 cases, with intensified transmission and expansion of high-transmission area. The predicted case number will be 9115 in 2022 and 19212 in 2025. CONCLUSIONS: The drastic upsurge in leishmaniasis cases in Sri Lanka in the last few year was unprecedented and it was strongly linked to precipitation, high burden of localized infections and inter-district dispersal. Targeted interventions are urgently needed to arrest an uncontrollable disease spread.Item What information and the extent of information research participants need in informed consent forms: a multi-country survey(BioMed Central, 2018) Karbwang, J.; Koonrungsesomboon, N.; Torres, C.E.; Jimenez, E.B.; Kaur, G.; Mathur, R.; Sholikhah, E.N.; Wanigatunge, C.; Wong, C.S.; Yimtae, K.; Abdul Malek, M.; Ahamad Fouzi, L.; Ali, A.; Chan, B.Z.; Chandratilake, M.; Chiew, S.C.; Chin, M.Y.C.; Gamage, M.; Gitek, I.; Hakimi, M.; Hussin, N.; Jamil, M.F.A.; Janarsan, P.; Julia, M.; Kanungo, S.; Karunanayake, P.; Kollanthavelu, S.; Kong, K.K.; Kueh, B.L.; Kulkarni, R.; Kumaran, P.P.; Kumarasiri, R.; Lim, W.H.; Lim, X.J.; Mahmud, F.; Mantaring, J.B.V.; Md Ali, S.M.; Mohd Noor, N.; Muhunthan, K.; Nagandran, E.; Noor, M.; Ooi, K.H.; Pradeepan, J.A.; Sadewa, A.H.; Samaranayake, N.; Sri Ranganathan, S.; Subasingha, W.; Subramanium, S.; Sulaiman, N.; Tay, J.F.; Teng, L.H.; Tew, M.M.; Tharavanij, T.; Tok, P.S.K.; Weeratna, J.; Wibawa, T.; Wickremasinghe, R.; Wongwai, P.; Yadav, S.; FERCAP Multi-Country Research TeamBACKGROUND: The use of lengthy, detailed, and complex informed consent forms (ICFs) is of paramount concern in biomedical research as it may not truly promote the rights and interests of research participants. The extent of information in ICFs has been the subject of debates for decades; however, no clear guidance is given. Thus, the objective of this study was to determine the perspectives of research participants about the type and extent of information they need when they are invited to participate in biomedical research. METHODS: This multi-center, cross-sectional, descriptive survey was conducted at 54 study sites in seven Asia-Pacific countries. A modified Likert-scale questionnaire was used to determine the importance of each element in the ICF among research participants of a biomedical study, with an anchored rating scale from 1 (not important) to 5 (very important). RESULTS: Of the 2484 questionnaires distributed, 2113 (85.1%) were returned. The majority of respondents considered most elements required in the ICF to be 'moderately important' to 'very important' for their decision making (mean score, ranging from 3.58 to 4.47). Major foreseeable risk, direct benefit, and common adverse effects of the intervention were considered to be of most concerned elements in the ICF (mean score = 4.47, 4.47, and 4.45, respectively). CONCLUSIONS: Research participants would like to be informed of the ICF elements required by ethical guidelines and regulations; however, the importance of each element varied, e.g., risk and benefit associated with research participants were considered to be more important than the general nature or technical details of research. Using a participant-oriented approach by providing more details of the participant-interested elements while avoiding unnecessarily lengthy details of other less important elements would enhance the quality of the ICF.Item Ten years of clinical trial registration in a resource-limited setting: Experience of the Sri Lanka clinical trials registry(Wiley-Blackwell, 2018) Ranawaka, U.K.; de Abrew, A.; Wimalachandra, M.; Samaranayake, N.; Goonaratna, C.AIM: We describe our experience of the first 10 years at the Sri Lanka Clinical Trials Registry (SLCTR). METHODS: We analyzed all trial records of the SLCTR over the study period. We collected information regarding trial characteristics and completeness of data entry in the SLCTR data set. RESULTS: During the study period, 210 trials (63% of all applications) were registered with the SLCTR. The number of registered trials showed an increasing trend over the years. All trial registrations had complete entries for all the data fields studied. Only 17.6% of the trials were registered retrospectively. All the registered trials were interventional studies, and the majority (87.6%) were randomized controlled trials. A significant proportion of trials (28.6%) were on noncommunicable diseases, and 12.4% were on pregnancy and its outcomes. Several trials (9.5%) were international collaborative studies. A majority of the Principal Investigators (70.9%) were affiliated to a university. Most of the studies (41.9%) were self-funded by the investigators. Details of ethics review committee approval were available for 96.7% of registered trials. Over a third of the registered trials (37.1%) had completed recruitment at the time of analysis. A majority of the trials (72.8%) had updated trial data since registration. CONCLUSIONS: There is a steady increase in the number of trials registered at the SLCTR. Complete entries for all the data fields were seen in all trial registrations. The SLCTR has made a positive contribution to the emergence of a healthy clinical research environment in Sri Lanka.Item Quality of clinical trial registration at the Sri Lanka clinical trials registry: a 5-year analysis(Sri Lanka Medical Association, 2017) Ranawaka, U.K.; de Abrew, A.; Ranasinghe, R.M.A.G.; Kulathunga, K.A.C.J.; Wimalachandra, M.; Samaranayake, N.; Goonaratna, C.INTRODUCTION & OBJECTIVES: Previous studies have highlighted the poor quality of clinical trial registration in international registries. We sought to evaluate the quality of trial registration in the Sri Lanka Clinical Trials Registry (SLCTR). METHODS: We studied all trial records at SLCTR over a 5-year period (2012-2016). Records were evaluated for data quality, using pre-defined criteria, regarding the following: WHO minimum trial registration data set (WHO-TRDS), ethics review approval, and detailed analysis of contact information, interventions and outcomes. RESULTS: A total of 144 trial records were studied. All records had meaningful entries for 12 out of the 20 items in WHO-TRDS, and over 95% of records had meaningful entries for 16 items, while the mean TRDS score was 17.76 ±1.03. Details of ethics approval were provided in all records. Intervention specifics were recorded for 174 experimental or active comparator arms. Meaningful information was provided regarding intervention name, dose, duration, frequency and route in 173 (99.4%). 156 (89.7%), 123 (70.7%), 132 (75.9%) and 109 (62.6%) arms respectively. A total of 388 primary outcome measures were recorded. Of them, 79.1% (n=307) were considered to be of good quality (specific – 76%; safety monitoring – 3.1%). Recording of time frame was considered to be of good quality for 94.4% (n=366) of outcomes (meaningful – 83.8%; irrelevant – 10.6%). All records provided either email address or telephone number of contact person; 98% (n= 141) had both. CONCLUSION: Quality of clinical trial registration at the SLCTR is better compared to other international registries in almost all the domains studied. Trial registration of good quality is feasible and sustainable in a resource-limited setting.