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BackgroundThere is a risk of novel mutations of SARS-CoV-2 that may render COVID-19 resistant to most of the therapies, including antiviral drugs. The evidence around the application of therapeutic plasma exchange (TPE) for the management of critically ill COVID-19 patients is still provisional and further investigations are needed to confirm its eventual beneficial effects. MethodsWe therefore carried out a single-centered retrospective observational non-placebo-controlled trial enrolling 73 inpatients from Baqiyatallah Hospital in Tehran (Iran) with diagnosis of COVID-19 pneumonia confirmed by real-time polymerase chain reaction (RT-PCR) on nasopharyngeal swabs and high-resolution computerized tomography chest scan. These patients were broken down into two groups: Group 1 (30 patients) receiving standard of care (corticosteroids, ceftriaxone, azithromycin, pantoprazole, hydroxychloroquine, lopinavir/ritonavir); and Group 2 (43 patients) receiving the above regimen plus TPE (replacing 2 liter of patients plasma by a solution, 50% of normal plasma and 50% of albumin at 5%) administered according to various time schedules. The follow-up time was 30 days and all-cause mortality was the endpoint. ResultsDeaths were 6 (14%) in Group 2 and 14 (47%) in Group 1. However, different harmful risk factors prevailed among patients not receiving TPE rather than being equally split between the intervention and control group. We used an algorithm of Structural Equation Modeling (of STATA) to summarize a large pool of potential confounders into a single score (called with the descriptive name "severity"). Disease severity was significantly (Wilkinson rank sum test p-value=0.0000) lower among COVID-19 patients undergoing TPE (median: -2.82; range: -5.18; 7.96) as compared to those non receiving TPE (median: -1.35; range: -3.89; 8.84), confirming that treatment assignment involved a selection bias of patients according to the severity of COVID-19 at hospital admission. The adjustment for confounding was carried out using severity as covariate in Cox regression models. The univariate Hazard Ratio (HR) of 0.68 (95%CI: 0.26; 1.80; p=0.441) for TPE turned to 1.19 (95%CI: 0.43; 3.29; p=0.741) after adjusting for severity. ConclusionsThe lower mortality observed among patients receiving TPE was due to a lower severity of COVID-19 rather than TPE effects. TRIAL REGISTRATIONIRCT registration number: IRCT20080901001165N58 (Iranian Registry of Clinical Trials) Registration date: 2020-05-27, 1399/03/07 (retrospectively registered)
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Objective: To determine the effect of climatic and environmental factors on the incidence of cutaneous leishmaniasis in Qom province in 2018. Methods: In this cross-sectional study, the data on cutaneous leishmaniasis incidence were collected from the Disease Control and Prevention Center in Qom province. Climatic and environmental data including Normalized Difference Vegetation Index (NDVI), Land Surface Temperature (LST), and soil moisture were extracted using satellite images. Data of altitude and sunny hours were provided based on shuttle radar topography mission digital elevation model and hemispherical viewshed algorithm, respectively. The associations of climatic and environmental variables with the incidence of the disease were analyzed by Pearson correlation method. The ArcGIS 10.3 software was used to determine the geographical distribution of these factors. Results: There were positive correlations between cutaneous leishmaniasis incidence and the two climatic factors: LST and sunny hours per day (P=0.041, P=0.016), and it had weak negative correlations with the digital elevation model (P=0.27), soil moisture (P=0.54), and NDVI (P=0.62). The time delay analysis showed that in one-, two-, and three month periods, the correlations increased with a 95% confidence interval. Accordingly, the correlation with the three-month time delay was positive and relatively strong between the cutaneous leishmaniasis incidence and LST and sunny hours (P=0.027, P=0.02); nevertheless, there were negative correlations between the cutaneous leishmaniasis incidence and the soil moisture (P=0.27) and NDVI (P=0.62). Conclusions: As Qom is located in one of the semi-arid climate zones, topography and solar energy are important factors affecting the incidence of cutaneous leishmaniasis in autumn. Therefore, appropriate disease control programs are recommended.
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Objective: To determine the effect of climatic and environmental factors on the incidence of cutaneous leishmaniasis in Qom province in 2018. Methods: In this cross-sectional study, the data on cutaneous leishmaniasis incidence were collected from the Disease Control and Prevention Center in Qom province. Climatic and environmental data including Normalized Difference Vegetation Index (NDVI), Land Surface Temperature (LST), and soil moisture were extracted using satellite images. Data of altitude and sunny hours were provided based on shuttle radar topography mission digital elevation model and hemispherical viewshed algorithm, respectively. The associations of climatic and environmental variables with the incidence of the disease were analyzed by Pearson correlation method. The ArcGIS 10.3 software was used to determine the geographical distribution of these factors. Results: There were positive correlations between cutaneous leishmaniasis incidence and the two climatic factors: LST and sunny hours per day (P=0.041, P=0.016), and it had weak negative correlations with the digital elevation model (P=0.27), soil moisture (P=0.54), and NDVI (P=0.62). The time delay analysis showed that in one-, two-, and three month periods, the correlations increased with a 95% confidence interval. Accordingly, the correlation with the three-month time delay was positive and relatively strong between the cutaneous leishmaniasis incidence and LST and sunny hours (P=0.027, P=0.02); nevertheless, there were negative correlations between the cutaneous leishmaniasis incidence and the soil moisture (P=0.27) and NDVI (P=0.62). Conclusions: As Qom is located in one of the semi-arid climate zones, topography and solar energy are important factors affecting the incidence of cutaneous leishmaniasis in autumn. Therefore, appropriate disease control programs are recommended.
