Molecular diagnosis of Chagas disease:a systematic review and meta-analysis

Background The complexity of the Chagas disease and its phases is impossible to have a unique test for both phases and a lot of different epidemiological scenarios.Currently,serology is the reference standard technique;occasionally,results are inconclusive,and a different diagnostic technique is needed.Some guidelines recommend molecular testing.A systematic review and meta-analysis of available molecular tools/techniques for the diagnosis of Chagas disease was performed to measure their heterogeneity and efficacy in detecting Trypanosoma cruzi infection in blood samples.Methods A systematic review was conducted up to July 27,2022,including studies published in international databases.Inclusion and exclusion criteria were defined to select eligible studies.Data were extracted and presented according to PRISMA 2020 guidelines.Study quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2(QUADAS-2).A random-effects model was used to calculate pooled sensitivity,specificity,and diagnostic odds ratio(DOR).Forest plots and a summary of the receiving operating characteristics(SROC)curves displayed the outcomes.Heterogeneity was determined by I^(2)and Tau^(2)statistics and P values.Funnel plots and Deek's test were used to assess publication bias.A quantitative meta-analysis of the different outcomes in the two different clinical phases was performed.Results We identified 858 records and selected 32 papers.Studies pertained to endemic countries and nonendemic areas with adult and paediatric populations.The sample sizes ranged from 17 to 708 patients.There were no concerns regarding the risk of bias and applicability of all included studies.A positive and nonsignificant correlation coefficient(S=0.020;P=0.992)was obtained in the set of studies that evaluated diagnostic tests in the acute phase population(ACD).A positive and significant correlation coefficient(S=0.597;P<0.000)was obtained in the case of studies performed in the chronic phase population(CCD).This resulted in high heterogeneity between studies,with the master mix origin and guanidine addition representing significant sources.Interpretation/Conclusions and relevance The results described in this meta-analysis(qualitative and quantitative analyses)do not allow the selection of the optimal protocol of molecular method for the study of Trypanosoma cruzi infection in any of its phases,among other reasons due to the complexity of this infection.Continuous analysis and optimization of the different molecular techniques is crucial to implement this efficient diagnosis in endemic areas.

Loiasis in sub-Saharan migrants living in Spain with emphasis of cases from Equatorial Guinea

Background:Loiasis is an uncommon and poorly understood parasitic disease outside endemic areas of Africa.The aim of this study was to describe the clinical and biological patterns and treatment of imported loiasis by sub-Saharan migrants diagnosed in Madrid,Spain.Methods:A retrospective study was conducted with sub-Saharan immigrants seen at the Tropical Medicine Unit of the Carlos III Hospital in Madrid,Spain,a reference center,over 19 years.Categorical variables were expressed as frequency counts and percentages.Continuous variables were expressed as the mean and standard deviation(SD)or median and interquartile range(IQR:Q3–Q1).Chi-square tests were used to assess the association between categorical variables.The measured outcomes were expressed as the odds ratio(OR)with a 95%confidential interval.Continuous variables were compared by Student’s t-tests or Mann-Whitney U tests.Binary logistic regression models were used.P<0.05 was considered a statistically significant difference.Results:One hundred thirty-one migrants from tropical and subtropical areas with loiasis were identified.Forty-nine patients were male(37.4%).The migrants’mean age(±SD)was 42.3±17.3 years,and 124(94.7%)were from Equatorial Guinea.The median time(IQR)between arrival in Spain and the first consultation was 2(1–7)months.One hundred fifteen migrants had eosinophilia,and one hundred thirteen had hyper-IgE syndrome.Fifty-seven patients had pruritus(43.5%),and thirty patients had Calabar swelling(22.9%).Seventy-three patients had coinfections with other filarial nematodes(54.2%),and 58 migrants had only Loa loa infections(45.8%).One hundred two patients(77.9%)were treated;45.1%(46/102)patients were treated with one drug,and 54.9%(56/102)patients were treated with combined therapy.Adverse reactions were described in 14(10.7%)migrants.Conclusions:Our patients presented early clinical manifestations and few atypical features.Thus,physicians should systematically consider loiasis in migrants with a typical presentation.However,considering that 72.5%of the patients had only positive microfilaremia without any symptoms,we suggest searching for microfilaremia in every migrant from endemic countries for loiasis presenting with eosinophilia.