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Browsing by Author "Premawansa, S."

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    Changes in full blood count parameters in leptospirosis: a prospective study
    (BioMed Central, 2014) de Silva, N.L.; Niloofa, M.; Fernando, N.; Karunanayake, L.; Rodrigo, C.; de Silva, H.J.; Premawansa, S.; Handunnetti, S.M.; Rajapakse, S.
    BACKGROUND: Leptospirosis presents diagnostic challenges to clinicians, in settings where other acute febrile illness are prevalent. The patterns of serial changes in haematological parameters in leptospirosis has not been evaluated previously. METHODS: Clinical and laboratory data were collected prospectively from patients with leptospirosis in two hospitals in Sri Lanka. Leptospirosis was diagnosed based on WHO clinical criteria with confirmation using Microscopic Agglutination Test titre > 400 or 4 fold rise between acute and convalescent samples. Full blood count parameters were analysed up to the 14th day of illness. RESULTS: Data from 201 patients with leptospirosis were available. Leukocyte counts and absolute neutrophil counts showed a decline over the first 5 days of illness, then rose until the end of the second week. On day 3 of fever, the majority (75%) had normal leukocyte counts, and by day 5, leukocytosis was seen only in 38.1%; leucopenia was an uncommon finding. Lymphopenia was seen in over half on day 5, declining to just under a quarter of patients by day 10. Platelets declined over the first 6 days and then gradually rose. Thrombocytopenia was seen in nearly three-fourths of patients by day 5. Haemoglobin and haematocrit levels declined over the course of illness. Total white cell and neutrophil counts were higher, and haemoglobin and haematorcrit were significantly lower, in patients with severe disease. CONCLUSIONS: Neither leukocytosis nor lymphopenia were prominent features, while thrombocytopenia was seen during the 3rd to 5th day of illness, with dropping haemoglobin levels. Neutrophilia and low haemoglobin levels appear to predict severe disease. These findings may be of use to clinicians in differentiating leptospirosis from other acute infections like dengue, and could help in predicting severe leptospirosis.
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    Clinical and laboratory associations of severity in a Sri Lankan cohort of patients with serologically confirmed Leptospirosis - a prospective study
    (Sri Lanka Medical Association, 2015) Rajapakse, S.; Weeratunga, P.N.; Rodrigo, C.; Sriharan, S.; Niloofa, M.J.R.; Fernando, N.; de Silva, H.J.; Karunanayake, L.; Premawansa, S.; Handunnetti, S.
    INTRODUCTION AND OBJECTIVES: Leptospirosis is a zoonotic infection of significant morbidity and mortality. This study elucidates the markers of severity in a cohort of Sri Lankan patients with serologically confirmed leptospirosis. METHOD: Prospectively recruited patients presenting to three healthcare institutions in the Western province of Sri Lanka with serological confirmation of leptospirosis with the microscopic agglutination test were included. Data regarding the socio-deruographic profile, clinical presentation, complications and biochemical parameters were recorded. Univariate associations and subsequent multivariate logistic regression models were constructed with severity as the dependent variable. RESULTS: A total of 232 patients were included. Majority were male (86.6%). Severe disease was noted in 68.5%. Significant clinical associations of severe disease included fever > 38.8°C on presentation (p=0.008), age>40 yrs; (p = 0.033), muscle tenderness (p=0.04) and tachycardia on admission (p=0.05). Laboratory associations of severe disease were highest white cell count > 12,350/mm3 (p<0.001) and < 7900/mm3 (p = 0.009), highest neutrophil percentage > 84% {p < 0.001). Hemoglobin > 11.2g/dL (p<0.001) and < 10.2 (p<0.001), packed cell volume > 33.8% (p <0.001) and <29.8% (p <0.001), lowest platelet count <63,500/mm3 (p = 0.01), highest ALT > 70 IU/L {p = 0.02) and hyponatremia with sodium <131mEq/L (p=0.004) On multivariate analysis, PCV < 29.8 (P = 0.011; adjusted OR =3.750; Cl = 1.394 - 10.423), ALT >70 P =0.044 adjusted OR =2.639; Cl =1.028-6.774 and hyponatremia< 131 (p=0.019 adjusted OR=6.413; Cl=1.353 -30.388) were found to be independent associations of severe disease. CONCLUSION: Severity associations were demonstrated with both clinical and laboratory parameters.
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    Clinico-epidemiological characteristics, treatment and outcomes of patients with confirmed Leptospirosis in a Sri Lankan healthcare setting
    (Sri Lanka Medical Association, 2015) Rajapakse, S.; Weeratunga, P.N.; Rodrigo, C.; Sriharan, S.; Niloofa, M.J.R.; Fernando, N.; de Silva, H.J.; Karunanayake, L.; Premawansa, S.
    INTRODUCTION AND OBJECTIVES: Leptospirosis is a zoonotic infection caused by spirochaetes of the genus Leptospira, with humans being affected as incidental hosts. Leptospirosis is endemic in Sri Lanka. There is paucity of prospective data on the clinico-epidemiological characteristics, treatment profiles and outcomes of patients with ieptospirosis in Sri Lanka. METHOD: This was a prospective cross sectional study of patients, over 12 years of age, with a diagnosis of ieptospirosis based on the WHO surveillance criteria with subsequent laboratory confirmation, presenting to three hospitals in the Western province of Sri Lanka. RESULTS: Of a total of 178 patients, males (84.3%) between the ages of 40-49 years were more likely to be affected. 51.7% were direct admissions and 47.8% were transfers. Exposure to water potentially contaminated with rat urine was seen in the majority (71.9%). A significant proportion of patients developed acute kidney injury (66.9%). Penicillin was the most commonly used antibiotic for treatment (47.2%), however more than one antibiotic was used in 43.3%. The use of chemoprophylaxis by the patients was low (1.1%). Hemodialysis was needed for 36.5%. Recovery was seen in 71.3%, 2.8% died, 10.1% were transferred out and 15.8% were lost to follow-up. On discharge, 70.6% had been treated for severe leptospirosis. Mean length of hospital stay was 7.5 days (±5.1). CONCLUSION: The incidence of severe leptospirosis with organ dysfunction is higher in patients presenting to hospitals in the .Western province. Males aged 40-49 are most commonly affected. More than two thirds of the patients developed acute kidney Injury. Chemoprophylaxis rates were low.
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    Comparison of HPLC profiles of venom of Apis darsata fabricius (Giant Asian Honey Bee) and Apis mellifera Linnaeus (Western Honey bee)
    (2016) Gunasekara, D.L.P.E.; Handunnetti, S.M.; Premawansa, S.; Dias, R.K.S.; Witharana, E.W.R.A.; Dassanayake, W.M.D.K.; Premakumara, G.A.K.; De Silva, N.R.
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    Development of an in-house ELISA as an alternative method for the serodiagnosis of leptospirosis
    (Elsevier, 2021) Niloofa, R.; Karunanayake, L.; de Silva, H.J.; Premawansa, S.; Rajapakse, S.; Handunnetti, S.
    BACKGROUND: Leptospirosis is most often clinically diagnosed and a laboratory test with high diagnostic accuracies is required. METHODOLOGY: IgM and IgG-ELISAs using Leptospira antigens were established and evaluated in relation to the Microscopic Agglutination Test (MAT). Antigen preparation consisted either saprophytic Leptospira biflexa to detect genus specific antibodies (genus-specific ELISA) or a pool of five most prevalent Leptospira interrogans serovars in Sri Lanka to detect serovar specific antibodies (serovar-specific ELISA). IgM and IgG immune responses in severe and mild leptospirosis patients (n = 100 in each group) were studied. RESULTS: ELISAs showed high repeatability and reproducibility. Serovar-specific IgM-ELISA showed sensitivity of 80.2% and specificity of 89%; genus-specific IgM-ELISA showed sensitivity of 83.3% and specificity of 91%. Serovar and genus-specific IgG-ELISA showed sensitivities of 73.3% and 81.7%, and specificities of 83.33%. Commercial IgM-ELISA showed sensitivity and specificity of 79.2% and 93% respectively. Commercial IgG-ELISA showed sensitivity, specificity of 50% and 96.7% respectively. IgM levels observed in mild and severe leptospirosis (ML & SL) patients were significantly higher than healthy control (HC) group, having absorbance mean of 0.770, 0.778 and 0.163 respectively. In contrast, SL patients had significantly higher mean anti-leptospiral IgG levels compared to both ML and HC groups (0.643, 0.358 and 0.116 respectively; ANOVA, P < 0.001). Presence of anti-leptospiral IgG above OD 0.643 optical density (OD) at 1:100 could predict high risk of severe disease. CONCLUSION: Serovar-specific In-House ELISAs could be used for the laboratory diagnosis of leptospirosis in endemic settings. Observed high levels of anti-leptospiral IgG suggest its value as a predictor for disease severity. KEYWORDS: IgM and IgG antibodies; In-House ELISA; Leptospirosis; Sero-diagnosis.
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    Diagnosis of leptospirosis: comparison between microscopic agglutination test, IgM-ELISA and IgM rapid immunochromatography test
    (Public Library of Science, 2015) Niloofa, R.; Fernando, N.; de Silva, N.L.; Karunanayake, L.; Wickramasinghe, H.; Dikmadugoda, N.; Premawansa, G.; Wickremasinghe, A.R.; de Silva, H.J.; Premawansa, S.; Rajapakse, S.; Handunnetti, S.
    BACKGROUND: Leptospirosis is diagnosed on clinical grounds, and confirmed by microscopic agglutination test (MAT). IgM-ELISA (Serion-Virion) and immunochromatography test (Leptocheck-WB) are two immunodiagnostic assays for leptospirosis. Their sensitivity, specificity and applicability in Sri Lanka have not been systematically evaluated. METHODS: Clinically diagnosed leptospirosis patients (n = 919) were recruited from three hospitals in the Western Province of Sri Lanka, during June 2012 to December 2013. MAT, IgM-ELISA and Leptocheck-WB were performed on all patient sera. MAT titer of ≥400 in single sample, four-fold rise or seroconversion ≥100 in paired samples were considered as positive for MAT. For diagnostic confirmation, MAT was performed during both acute and convalescent phases. Anti-leptospiral IgM ≥20 IU/ml and appearance of a band in the test window were considered as positive for IgM-ELISA and Leptocheck-WB test respectively. Patients with an alternative diagnosis (n = 31) were excluded. Data analysis was performed using two methods, i) considering MAT as reference standard and ii) using Bayesian latent class model analysis (BLCM) which considers each test as imperfect. RESULTS: MAT, IgM-ELISA and Leptocheck-WB positivity were 39.8%, 45.8% and 38.7% respectively during the acute phase. Acute-phase MAT had specificity and sensitivity of 95.7% and 55.3% respectively, when compared to overall MAT positivity. IgM-ELISA and Leptocheck-WB had similar diagnostic sensitivity when compared with acute-phase MAT as the gold standard, although IgM-ELISA showed higher specificity (84.5%) than Leptocheck-WB (73.3%). BLCM analysis showed that IgM-ELISA and Leptocheck-WB had similar sensitivities (86.0% and 87.4%), while acute-phase MAT had the lowest sensitivity (77.4%). However, acute-phase MAT had high specificity (97.6%), while IgM-ELISA and Leptocheck-WB showed similar but lower specificity (84.5% and 82.9%). CONCLUSIONS: Both IgM-ELISA and Leptocheck-WB shows similar sensitivities and specificities. IgM-ELISA may be superior to MAT during the acute phase and suitable for early diagnosis of leptospirosis. Leptocheck-WB is suitable as a rapid immunodiagnostic screening test for resource limited settings.
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    Diagnosis of Vespa affinis venom allergy:use of immunochemical methods and a passive basophil activation test
    (Allergy, Asthma & Clinical Immunology, 2019) Gunasekara, P.; Handunnetti, S.M.; Premawansa, S.; Kaluarachchi, P.; Karunatilake, C.; Ratnayake, I.P.; Dias, R. K. S.; Premakumara, G. A. S.; Dasanayake, W. M. D. K.; Seneviratne, S.L.; de Silva, R.
    Background: Allergy to Vespa affinis venom is common in the Asia Pacific region. Venom preparations for diagnosis are not commercially available for this species. Methods: The prominent allergens in V. affinis venom were identifiedusing immunochemical methods. Use of ImmunoCAP of Vespula vulgaris crude venom/its components and a passive basophil activation test (BAT) in the diagnosis of patients who had anaphylaxis to V. affinis venom (n = 30) were also accessed. The IgE double-positivity rates (positive to both hornet and honeybee) in ImmunoCAP and the passive BAT were determined. Results: High IgE reactivity was seen with the five allergens in V. affinis venom; 96% (29/30) for 34 and 24 kDa, 93% (28/30) for 45 kDa and 90% (27/30) reactivity for the 100 and 80 kDa respectively. IgE cross-reactivity was low with ImmunoCAP using V. vulgaris venom (43%; 13/30) and Ves v1 (3%; 1/30), but relatively high with Ves v5 (73%; 22/30). All patients (100%) were positive to V. affinis venom in passive BAT. In ImmunoCAP, a high double-positivity rate (76%; 23/30) was detected while no double-positivity was detected in passive BAT. Conclusions: High IgE reactivity for five allergens of V. affinis points to the potential of using these allergens in component resolved diagnosis (CRD). The passive BAT has shown its importance as a promising diagnostic tool with high accuracy. It would be particularly useful in cases with doubtful double-positive results of other diagnostic tests.
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    A diagnostic model for Leptospirosis for use in resource limited settings
    (Sri Lanka Medical Association, 2015) Rajapakse, S.; Weeratunga, P.N.; Rodrigo, C.; Sriharan, S.; Niloofa, M.J.R.; Fernando, N.; de Silva, H.J.; Karunanayake, L.; Premawansa, S.
    INTRODUCTION AND OBJECTIVES: Leptospirosis is a zoonotic infection with significant morbidity and mortality. In this prospective study, we attempted to develop a model for diagnosis of leptospirosis. METHOD: Data was extracted from a prospective multicentre study. All patients with a suspected diagnosis of leptospirosis based on the WHO surveillance criteria were recruited. A derivation cohort and a validation cohort were selected. Positive MAT was used as the gold standard and significant associations in the derivation cohort were selected for construction of a multivariate regression model. Adjusted odds ratios were extracted for significant variables. ROC curves were generated. RESULTS: A total of 592 patients were included with 450 (180 confirmed leptospirosis) in the derivation cohort and 142 (52 confirmed leptospirosis) in the validation cohort. The variables in the final model were: history of exposure to possible source of leptospirosis (OR=2.878;95% Cl=1.527-5.425;p=0.001), serum creatinine>150u.mol/L (OR =2.742; 95% CN1.474-5.101; p=0.001), neutrophil differential percentage (on day 3 of illness) > 82.8% of total WBC count (OR 2.063; 95% Cl = 1.109 - 3.837; p =0.022), serum bilirubin > 27 U/L (OR = 1.767;95%CI 0.968 - 3.226; p=0.050) and platelet count (on day 3 of illness)< 85,000/mm3 (OR=2.350; 95%CI=1.281 -4.313;p=0.006). The Nagelkerke R2 was 0.654. ROC analysis demonstrated a diagnostic model score >14 to have a sensitivity of 80% and a specificity of 60% in the diagnosis of leptospirosis against MAT as the gold standard. CONCLUSION: This proposed diagnostic model for diagnosis of leptospirosis is of potential value to clinicians treating acute febrile illness in areas with limited diagnostic facilities.
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    A Diagnostic scoring model for Leptospirosis in resource limited settings
    (Public Library of Science, 2016) Rajapakse, S.; Weeratunga, P.; Niloofa, R.; Fernando, N.; de Silva, N.L.; Rodrigo, C.; Maduranga, S.; Nandasiri, N.; Premawansa, S.; Karunanayake, L.; de Silva, H.J.; Handunnetti, S.
    Leptospirosis is a zoonotic infection with significant morbidity and mortality. The clinical presentation of leptospirosis is known to mimic the clinical profile of other prevalent tropical fevers. Laboratory confirmation of leptospirosis is based on the reference standard microscopic agglutination test (MAT), direct demonstration of the organism, and isolation by culture and DNA detection by polymerase chain reaction (PCR) amplification. However these methods of confirmation are not widely available in resource limited settings where the infection is prevalent, and reliance is placed on clinical features for provisional diagnosis. In this prospective study, we attempted to develop a model for diagnosis of leptospirosis, based on clinical features and standard laboratory test results. METHODS: The diagnostic score was developed based on data from a prospective multicentre study in two hospitals in the Western Province of Sri Lanka. All patients presenting to these hospitals with a suspected diagnosis of leptospirosis, based on the WHO surveillance criteria, were recruited. Confirmed disease was defined as positive genus specific MAT (Leptospira biflexa). A derivation cohort and a validation cohort were randomly selected from available data. Clinical and laboratory manifestations associated with confirmed leptospirosis in the derivation cohort were selected for construction of a multivariate regression model with correlation matrices, and adjusted odds ratios were extracted for significant variables. The odds ratios thus derived were subsequently utilized in the criteria model, and sensitivity and specificity examined with ROC curves. RESULTS: A total of 592 patients were included in the final analysis with 450 (180 confirmed leptospirosis) in the derivation cohort and 142 (52 confirmed leptospirosis) in the validation cohort. The variables in the final model were: history of exposure to a possible source of leptospirosis(adjusted OR = 2.827; 95% CI = 1.517-5.435; p = 0.001) serum creatinine > 150 micromol/l (adjusted OR = 2.735; 95% CI = 1.374-4.901; p = 0.001), neutrophil differential percentage > 80.0% of total white blood cell count (adjusted OR 2.163; 95% CI = 1.309-3.847; p = 0.032), serum bilirubin > 30 micromol/l (adjusted OR = 1.717; 95% CI 0.938-3.456; p = 0.049) and platelet count < 85,000/mm3 (adjusted OR = 2.350; 95% CI = 1.481-4.513; p = 0.006). Hosmer-Lemeshow test for goodness of fit was 0.931. The Nagelkerke R2 was 0.622. The area under the curve (AUC) was noted as 0.762. A score value of 14 reflected a sensitivity of 0.803, specificity of 0.602, a PPV of 0.54, NPV of 0.84, a positive LR of 2.01 and a negative LR of 0.32. CONCLUSIONS: The above diagnostic model for diagnosis of leptospirosis is suggested for use in clinical settings. It should be further validated in clinical practice.
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    Effect of antimicrobial agents on inflammatory cytokines in acute Leptospirosis
    (American Society for Microbiology, 2018) Fernando, N.; de Silva, R.; Hadunnetti, S.M.; Karunanayake, L.; de Silva, N.L.; de Silva, H.J.; Rajapakse, S.; Premawansa, S.
    The aim of this study was to assess the inflammatory cytokine response and possible association with antimicrobial treatment with penicillin, ceftriaxone, and doxycycline in acute leptospirosis. In the early acute stage, interleukin-10 (IL-10) levels were higher in mild cases than in severe cases (P = 0.01). IL-6 and IL-8 levels were low in patients who received >5 antimicrobial doses (P < 0.01). IL-8 levels were negatively correlated with the number of ceftriaxone doses administered (r = -0.315; P = 0.031). Further studies are needed to evaluate the possible downregulation of proinflammatory cytokines by ceftriaxone in leptospirosis.
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    High levels of serum angiopoietin 2 and angiopoietin 2/1 ratio at the critical stage of Dengue Hemorrhagic Fever in patients and association with clinical and biochemical parameters
    (American Society for Microbiology., 2020) Mapalagamage, M.; Handunnetti, S.M.; Wickremasinghe, A.R.; Premawansa, G.; Thillainathan, S.; Fernando, T.; Kanapathippillai, K.; de Silva, A.D.; Premawansa, S.
    ABSTRACT:Longitudinal changes of serum angiopoietin 1 (Ang-1) and angiopoietin 2 (Ang-2) associated with endothelial stability in dengue patients with different disease stages were studied. Serum Ang-1 and Ang-2 levels were measured in confirmed dengue fever (DF) patients on admission (DFA, n = 40) and discharge (DFD, n = 20); in dengue hemorrhagic fever (DHF) patients on admission (DHFA, n = 40), at critical stage (DHFC, n = 36), and on discharge (DHFD, n = 20); and in healthy controls (HC, n = 25). DHFC had the highest serum Ang-2 and lowest Ang-1 levels compared to DFA, DHFA, and HC (P < 0.050). The ratio of serum Ang-2/Ang-1 in DHFC was the highest among all study categories tested (P < 0.001). Significant positive correlations were observed between serum Ang-1 and platelet count in DHFA (Pearson r = 0.653, P < 0.001) and between Ang-1 and pulse pressure in DHFC (r = 0.636, P = 0.001). Using a cutoff value of 1.01 for the Ang-2/Ang-1 ratio for DHFC, a sensitivity of 83.2% and a specificity of 81.2% discerning DF from DHF were obtained. Therefore, serum Ang-2/Ang-1 could be used as a biomarker for endothelial dysfunction in severe dengue at the critical stage. KEYWORDS: angiopoietin; biomarker; dengue fever; dengue hemorrhagic fever; endothelial dysfunction.
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    Immunochemical characterization of venom of Apis dorsata Fabricus (Bambara) in Sri Lanka (Hymenoptera; Apidae)
    (Institute of Biochemistry, Molecular Biology and Biotechnology, University of Colombo, Sri Lanka., 2015) Gunasekara, D.L.P.E.; De Silva, N.R.; Handunnetti, S.M.; Dias, R.K.S.; Witharana, E.W.R.A.; Dasanayake, W.M.D.K.; Premawansa, S.
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    Immunochemical characterization of venom of medically important ants in Sri Lanka and determination of ant cross-reactivity with western ant species
    (2016) de Silva, B.D.; Handunnetti, S.M.; Premawansa, S.; Dias, R.K.S.; De Silva, N.R.
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    Is Total Serum Nitrite and Nitrate (NOx) Level in Dengue Patients a Potential Prognostic Marker of Dengue Hemorrhagic Fever?
    (Hindawi Pub. Corp., 2018) Mapalagamage, M.; Handunnetti, S.; Premawansa, G.; Thillainathan, S.; Fernando, T.; Kanapathippillai, K.; Wickremasinghe, R.; de Silva, A.D.; Premawansa, S.
    Potential use of total nitrite plus nitrate (NOx) and nitrite (NO2-) separately as surrogate markers for serum nitric oxide in severe dengue and their longitudinal changes along with the progression of infection was studied. Deproteinized sera from confirmed dengue fever (DF, n = 145) and dengue hemorrhagic fever (DHF, n = 74) patients on admission-A, critical-C, discharge-D, and convalescence-CON stages and from age-gender matched healthy individuals (HC, n = 77) were taken to assess NO2- and NOx levels using Griess and modified Griess assays. Serum NOx in DHFA was significantly lower compared to DFA (p < 0.001). HC had the lowest NOx and NO2- compared to all patient categories (p < 0.001) except NO2- in DF-CON and DHF-CON and NOx in DHF-CON. Serum NOx and NO2- in DHF patients admitted on fever day 3 (DHFA-3) was significantly lower compared to DFA-3 (p < 0.05). Cut-off values of 4.46 μM for NOx (91.3% sensitivity and 80.1% specificity) and 1.25 μM for NO2-(75.0% sensitivity and 73.3% specificity) were obtained for day 3 of fever. Serum NOx may be used as potential prognostic marker of DHF in patients presenting with DF in the early stage (on day 3 of fever) of the disease.
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    Leptospirosis: challenges in diagnosis, and predictors of severity
    (Ceylon College of Physicians, 2016) Rajapakse, S.; Fernando, N.; Niloofa, M.J.R.; de Silva, H.J.; Karunanayake, L.; Premawansa, S.; Handunnetti, S.M.
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    The ParaSightT-F dipstick test as a routine diagnostic tool for malaria in Sri Lanka
    (Oxford University Press, 1997) Kodisinghe, H.M.; Perera, K.L.R.L.; Premawansa, S.; Naotunne, T. de S.; Wickremasinghe, A.R.; Mendis, K.N.
    Blood from 1053 persons who presented for treatment at outpatient clinics of government health institutions in Sri Lanka, and 250 who took part in a blood survey for malaria, was examined by thick blood film microscopy under routine field conditions, and by the ParaSight-F dipstick method. All the samples were also examined microscopically under laboratory conditions when 4 times the number of microscope fields were examined. Compared with this reference standard, the sensitivity and specificity of the ParaSight-F test were 90.2% and 99.1%, and those of microscopy in the field were 92.4% and 98.4% respectively, there being no statistically significant difference between the 2 methods. The ParaSight-F test reading correlated significantly and positively with the intensity of clinical disease of patients but not with their peripheral parasitaemia, indicating that it may be a more accurate measure of the true parasite load than microscopy, which detects only parasites which are in the peripheral blood and not those which are sequestered in deep organs. The ParaSight-F test, however, failed to detect Plasmodium falciparum infections with only gametocytes in the blood (19.6% of the infected blood samples in this study). The time taken for a patient to revert to negativity by the ParaSight-F test was also significantly longer, up to 14 d. This would make the test unsuitable for checking the response to antimalarial treatment within 14 d. In an endemic area it would therefore fail to detect drug resistant populations of parasites.
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    Predictive value of hepatic transaminases during febrile phase as a predictor of a severe form of dengue: analysis of adult dengue patients from a tertiary care setting of Sri Lanka
    (Biomed Central, 2021) Priyangika, D.K.D.; Premawansa, G.; Adikari, M.; Thillainathan, S.; Premawansa, S.; Jayamanne, B.D.W.; Premaratna, R.
    OBJECTIVES: Dengue viral infection is an ongoing epidemic in Sri Lanka, causing significant mortality and morbidity. A descriptive-analytical study was carried out using serologically confirmed Dengue patients during a 6-month period. The relationship between the elevation of hepatic enzymes and severity of Dengue was assessed after stratifying recorded maximum AST/ALT (SGOT/SGPT) values 2-15 times elevated and by the phases of the illness. Sensitivity, specificity, predictive values, and ROC curves were assessed using maximum values for AST and ALT. RESULTS: Out of 255 patients, 107(42%) were females. The majority (52.9%) were in the 20-39-year age group. Only 19.6% had DHF. No statistically significant difference was noticed in the values of maximum transaminases during the febrile phase among DF and DHF patients. Higher sensitivity and low specificity with the 1-5 times elevation range was noticed, and a higher cut-off level of more than 5 times elevation showed low sensitivity and higher specificity. The combination of both transaminases cut-offs with age and sex also does not show clinically significant predictability of severe disease. The AST and ALT elevations are not showing discriminatory predictive value on dengue severity. As different serotypes cause different epidemics, it is important to carry out large-scale specific studies considering the serotypes. KEYWORDS: And liver enzymes; Dengue; Dengue severity prediction; Transaminases in Dengue.
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    Protein Carbonyl as a biomarker of oxidative stress in severe Leptospirosis, and its usefulness in differentiating Leptospirosis from Dengue Infections
    (Public Library of Science, 2016) Fernando, N.; Wickremesinghe, S.; Niloofa, R.; Rodrigo, C.; Karunanayake, L.; de Silva, H.J.; Wickremasinghe, A.R.; Premawansa, S.; Rajapakse, S.; Handunnetti, S.M.
    Pathogenesis of disease severity in leptospirosis is not clearly understood whether it is due to direct damage by pathogen or by adverse immune responses. Knowledge on biomarkers of oxidative stress which could be used in identifying patients with severe illness has shown to be of great value in disease management. Thus, the main aim of this study was to assess the damage to serum proteins and lipids, and their significance as biomarkers of oxidative stress in severe leptospirosis. In regions endemic for both leptospirosis and dengue, leptospirosis cases are often misdiagnosed as dengue during dengue epidemics. Therefore, the second aim was to assess the potential of the oxidative stress markers in differentiating severe leptospirosis from critical phase dengue. We measured serum antioxidants (uric acid and bilirubin), total antioxidant capacity (AOC), protein carbonyl (PC) and lipid hydroperoxide (LP) in patients with severe leptospirosis (n = 60), mild leptospirosis (n = 50), dengue during the critical phase (n = 30) and in healthy subjects (n = 30). All patient groups had similar total antioxidant capacity levels. However, the presence of significantly high uric acid and total bilirubin levels may reflect the degree of renal and hepatic involvement seen in severe leptospirosis patients (p<0.02). Serum PC and LP levels were significantly higher in leptospirosis patients compared to critical phase dengue infections (p<0.005). Moreover, high serum PC levels appear to differentiate SL from DC [area under the curve (AUC) = 0.96; p<0.001]. Serum PC may be a reliable biomarker of oxidative damage to serum proteins to identify severe leptospirosis patients (AUC = 0.99) and also to differentiate severe leptospirosis from mild cases (AUC = 0.78; p<0.005) indicating its contribution to pathogenesis. Use of serum PC as an indicator of leptospirosis severity and as an oxidative stress biomarker in differentiating leptospirosis from dengue would provide the opportunity to save lives via prompt patient management.

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