ML Flow serological test: complementary tool in leprosy.

BACKGROUND: The evaluation of household contacts of leprosy cases allows the early diagnosis of new cases. OBJECTIVE: To associate the results of the ML Flow test with the clinical characteristics of leprosy cases and to verify their positivity in household contacts, in addition to describing the epidemiological profile of both. METHODS: Prospective study with patients diagnosed over the course of one year (n = 26), without prior treatment, and their household contacts (n = 44) in six municipalities in northwestern São Paulo, Brazil. RESULTS: There was a predominance of men among the leprosy cases, of 61.5% (16/26); 77% (20/26) were over 35 years old; 86.4% (22/26) were multibacillary; 61.5% (16/26) had a positive bacilloscopy; and 65.4% (17/26) had no physical disability. The ML Flow test was positive in 53.8% (14/26) of the leprosy cases and was associated with those who had a positive bacilloscopy and were diagnosed as multibacillary (p-value <0.05). Among the household contacts, 52.3% (23/44) were women and aged over 35 years; 81.8% (36/44) had been vaccinated with BCG ‒ Bacillus Calmette-Guérin. The ML Flow test was positive in 27.3% (12/44) of household contacts, all of whom lived with multibacillary cases; seven lived with positive bacilloscopy cases and six with consanguineous cases. STUDY LIMITATIONS: Difficulty in convincing the contacts to undergo the evaluation and collection of the clinical sample. CONCLUSION: The ML Flow test, when positive in household contacts, can help the identification of cases that require more attention by the health team, as it indicates a predisposition to disease development, especially when they are household contacts of multibacillary cases, with positive bacilloscopy and consanguineous. The ML Flow test also helps in the correct clinical classification of the leprosy cases.

Multiplex peptide microarray profiling of antibody reactivity against neglected tropical diseases derived B-cell epitopes for serodiagnosis in Zimbabwe.

INTRODUCTION: Peptides (B-cell epitopes) have broad applications in disease diagnosis and surveillance of pathogen exposure. In this framework, we present a pilot study to design and produce a peptide microarray for the integrated surveillance of neglected tropical diseases. The peptide microarray was evaluated against peptides derived from Ascaris lumbricoides, Necator americanus, Schistosoma haematobium, Schistosoma mansoni, Trichuris trichiura, Bacillus anthracis, Mycobacterium leprae, Wuchereria bancrofti, Rabies lyssavirus, Chlamydia trachomatis and Trypanosoma brucei. METHODS: S. haematobium was diagnosed using the urine filtration technique. S. mansoni, A. lumbricoides, N. americanus and T. trichiura were diagnosed using the Kato Katz and formal ether concentration techniques. Immunogenic peptides were retrieved from the Tackling Infection to Benefit Africa infectious diseases epitope microarray. Further peptides were predicted using ABCpred. IgG and IgM reactivity against the derived peptides were evaluated using peptide microarray multiplex immunoassays. Positive response was defined as fluorescence intensity ≥ 500 fluorescence units. Immunodominant peptides were identified using color-coded heat maps and bar graphs reflecting the obtained fluorescence signal intensities. Receiver Operating Characteristic analysis and Mann-Whitney-U test were performed to determine the diagnostic validity of the peptides. RESULTS: Species-specific responses with at least one peptide derived from each NTD pathogen were observed. The reactive peptides included; for S. haematobium, XP_035588858.1-206-220 and XP_035588858.1-206-220 immunodominant for IgG and IgM respectively, for S. mansoni, P20287.1-58-72 immunodominant for both antibodies and for T. trichiura, CDW52482.1-326-340 immunodominant for IgG and CDW57769.1-2017-2031 and CDW57769.1-1518-1532 immunodominant for IgM. According to ROC analysis most of the peptides selected were inaccurate; with AUC < 0.5. Some peptides had AUC values ranging from 0.5 to 0.5875 for both IgM and IgG suggesting no discrimination. CONCLUSION: Multiplex peptide microarrays are a valuable tool for integrated NTDs surveillance and for screening parasites exposure in endemic areas. Species sero-reactivity observed in the study maybe indicative of exposure to the different NTDs parasites. However, although peptides with the least cross reactivity were selected there is need to validate the sero-reactivity with recombinant antigens and immune-blotting techniques such as western blotting.

Accuracy of rapid point-of-care serological tests for leprosy diagnosis: a systematic review and meta-analysis.

BACKGROUND: Leprosy is a chronic infectious disease, still endemic in many countries that may lead to neurological, ophthalmic, and motor sequelae if not treated early. Access to timely diagnosis and multidrug therapy (MDT) remains a crucial element in the World Health Organization's strategy to eliminate the disease as a public health problem. OBJECTIVES: This systematic review aims to evaluate the accuracy of rapid point-of-care (POC) tests for diagnosis of leprosy. METHODS: Searches were carried out in electronic databases (PubMed, EMBASE, CRD, Cochrane Library and LILACS) in April 2021 for patients with suspicion or confirmatory diagnostic of leprosy, classified in multibacillary (MB) or paucibacillary (PB) cases, performing rapid POC serological tests compared to clinical evaluation, smear microscopy and immunohistochemistry analysis. Methodological quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS-2). A meta-analysis was undertaken to generate pooled estimates of diagnostic parameters, presenting sensitivity, specificity and diagnostic odds ratio (DOR) values. The review protocol was registered at PROSPERO, CRD # 42014009658. FINDINGS: From 893 potentially relevant references, 12 articles were included reporting 16 diagnostic tests accuracy studies with 5395 individuals enrolled. Meta-analysis of NDO-LID and PGL-I tests data in MB patients showed sensitivity and specificity [95% confidence interval (CI)] of 0.83 (0.71-0.91), 0.91 (0.72-0.97); and 0.92 (0.86-0.96), 0.93 (0.78-0.98); respectively, with high heterogeneity among the studies. MAIN CONCLUSIONS: Our results can inform policymakers regarding the possibility of implementing accurate, rapid POC tests for leprosy in public health services, especially within primary health care.

O uso do teste Ml flow entre casos de hanseníase recém-diagnosticados e contatos intradomiciliares / The use of the Ml flow test between newly diagnostic leprosy cases and in-home contacts / El uso de la prueba de flujo Ml entre casos de lepra recientemente diagnósticos y contactos en el hogar

Objetivo: identificar o resultado de teste Ml Flow entre casos de hanseníase recém-diagnosticados e contatos intradomiciliares.Métodos: estudo transversal, descritivo, com abordagem quantitativa realizado no município de Caxias, Maranhão, Brasil, onde recrutou-se casos recém-diagnosticados, virgens de tratamento e contatos intradomiciliares. Resultados: recrutou-se 324 contatos de casos de hanseníase, no período de 2015 a 2018. Nos casos recém-diagnosticados o teste Ml Flow foi negativo em 87,5% (7/8) dos paucibacilares e positivo em 70% (21/30) dos multibacilares, ambos concordantes com a baciloscopia do raspado intradérmico. Identificou-se 30 (9%) contatos intradomiciliares com alto risco de adoecer. Conclusão: o teste Ml Flow constitui-se uma ferramenta útil para correta detecção de contatos com alta chance de adoecer da hanseníase, bem como para classificar corretamente os casos novos

Objective: to identify the Ml Flow test result between newly diagnosed leprosy cases and household contacts. Methods: cross-sectional, descriptive study with a quantitative approach carried out in the city of Caxias, Maranhão, Brazil, where newly diagnosed cases, treatment virgins and intra-household contacts were recruited. Results: 324 contacts of leprosy cases were recruited from 2015 to 2018. In newly diagnosed cases, the Ml Flow test was negative in 87.5% (7/8) of paucibacillary patients and positive in 70% (21/ 30) of the multibacillary, both in agreement with the bacilloscopy of the intradermal smear. Thirty (9%) household contacts with high risk of illness were identified. Conclusion: the Ml Flow test is a useful tool for the correct detection of contacts with a high chance of getting sick from leprosy, as well as for correctly classifying new cases

Objetivo: identificar el resultado de la prueba Ml Flow entre casos de lepra recién diagnosticados y contactos domésticos. Métodos: estudio descriptivo transversal con abordaje cuantitativo realizado en la ciudad de Caxias, Maranhão, Brasil, donde se reclutaron casos recién diagnosticados, vírgenes en tratamiento y contactos intrafamiliares. Resultados: se reclutaron 324 contactos de casos de lepra entre 2015 y 2018. En los casos recién diagnosticados, la prueba Ml Flow fue negativa en el 87,5% (7/8) de los pacientes paucibacilares y positiva en el 70% (21/30) de los multibacilares, ambos de acuerdo con la baciloscopia del frotis intradérmico. Identificamos 30 (9%) contactos dentro del hogar con alto riesgo de enfermarse. Conclusión: la prueba Ml Flow es una herramienta útil para la correcta detección de contactos con alta probabilidad de enfermarse de lepra, así como para clasificar correctamente nuevos casos

Potential of recombinant LiHyQ, a novel Leishmania infantum protein, for the diagnosis of canine visceral leishmaniasis and as a diagnostic and prognostic marker for human leishmaniasis and human immunodeficiency virus co-infection: A preliminary study.

Laboratory diagnosis of leishmaniasis shows variable efficacy in detecting infected mammalian hosts and there is a need to identify suitable antigens to improve the accuracy of diagnostic tests. In the present study, a L. infantum hypothetical protein called LiHyQ was evaluated for the diagnosis of tegumentary (TL) and visceral (VL) leishmaniasis using canine and human samples. A collection of dog sera (n=155) were tested and contained samples from asymptomatic (n=20) and symptomatic (n=25) VL animals, from healthy dogs living in endemic (n=25) or non-endemic (n=25) areas of disease, from Leish-Tec® vaccinated dogs (n=20) or from dogs infected with Ehrlichia canis (n=15), Babesia canis (n=10) and Trypanosoma cruzi (n=15). Sensitivity (Se), Specificity (Sp), Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of 100% were observed for rLiHyQ with these samples, whereas the Se, Sp, PPV and NPV values with L. infantum Soluble Leishmania Antigen (SLA) preparation were 60.0%, 99.0%, 96.0% and 86.0%, respectively. A collection of human sera (n=305) were tested and contained samples from TL (n=50) and VL (n=40) patients, from VL/HIV co-infected patients (n=35), from patients infected with HIV alone (n=30), Chagas Disease (n=30), malaria (n=10), tuberculosis (n=10), paracoccidioidomycosis (n=15), leprosy (n=30) or aspergillosis (n=15); and from healthy subjects (n=40). Se, Sp, PPV and NPV values of 100% were observed for rLiHyQ with these samples, whereas the Se, Sp, PPV and NPV values with SLA were 58.0%, 76.0%, 50.0% and 82.0%, respectively. The antibody reactivity against the protein was compared with commercial kits, and the kappa index varied from 0.95 to 1.00 for rLiHyQ, and of 0.55 to 0.82 for the kits. In addition, the serological follow-up of treated patients showed a significant reduction in rLiHyQ-specific IgG antibody levels. All canine and human samples were tested at the same time using the same reagents, in order to reduce experimental variation and interference in data interpretation. In conclusion, our preliminary data suggest a diagnostic and prognostic role for rLiHyQ against leishmaniasis.

Epitope mapping from Mycobacterium leprae proteins: Convergent data from in silico and in vitro approaches for serodiagnosis of leprosy.

Knowledge of immunodominant B-cell epitopes is essential to design powerful diagnostic strategies aiming for antibody detection. Outstanding progress in computational prediction has achieved a significant contribution to the biomedical fields, including immunodiagnosis. In silico analysis may have an even more important role when information concerning antigens from etiologic agents of neglected diseases, such as leprosy, is scarce. The aim of this study was to provide mapping of B-cell epitopes from two Mycobacterium leprae-derived antigens (Ag85B and ML2055), confirm their antigenicity, and to assess the ability of in silico immunoinformatics tools to accurately predict them. Linear B-cell epitopes predicted by ABCpred and SVMTrip servers were compared to antigenic regions of synthetic overlapping peptides that exhibited reactivity to antibodies from patients with leprosy. Our in vitro results identified several immunodominant regions that had also been indicated by in silico prediction, providing agreement between experimental and simulated data. After chemical synthesis, we used enzyme-linked immunosorbent assays to determine the effectiveness of the first identified sequence (GTNVPAEFLENFVHG) which had 72 % sensitivity and 78 % specificity (AUC = 0.79) while the second one (PVSSEAQPGDPNAPS) had 72 % sensitivity and 93.8 % specificity (AUC = 0.85). Using dot blotting, an easy-to-read visual test, both peptides could distinguish sera from patients with leprosy from those with tuberculosis and from sera of healthy volunteers. Our findings suggest that these synthetic peptides, with some refinement, may be useful as serological diagnostic antigens for leprosy. In addition, it was displayed that immunoinformatics provides reliable information for mapping potential B-cell epitopes for development of peptide-based diagnostic assays for neglected diseases.

Hanseníase Neural Primária - Dr. Diogo Fernandes

Conferência Hanseníase Neural Primária: aspectos clínicos, sorológicos, neurofisiológicos, histopatológico e molecular ministrada pelo Dr. Diogo Fernandes no 2º Simpósio Cearense de Hansenologia

Prospects for new leprosy diagnostic tools, a narrative review considering ELISA and PCR assays.

Slit skin smear and histopathological examinations are currently the main laboratory tools used to aid the diagnosis of leprosy. However, their sensitivity is low, and many cases are not detected. New methodologies have been studied to develop more accurate tests. This narrative review aims to raise attention to the results of molecular (polymerase chain reaction) and serological (Enzyme-Linked Immunosorbent Assay) tests applied to the diagnosis of leprosy, and to summarize the available information about the former. Original scientific articles published in indexed international journals, whose study involved aspects of the diagnosis and classification of leprosy cases or home contacts, were selected. The data were extracted independently using a standardized method that dictated the inclusion of the following information: diagnosis in Paucibacillary and Multibacillary cases and in household contacts; sample number; sample type; study design; studied variables; statistical analysis employed; main results; and limitations identified. In clinical practice, the results from molecular and serological tests are assessed separately, with moderate sensitivity and specificity. However, an integrated study of these methodologies has been suggested for greater accuracy in diagnosis.

Mycobacterium leprae: Pathogenesis, diagnosis, and treatment options.

Mycobacterium leprae is known to cause leprosy, a neurological and dermatological disease. In the past 20 years, 16 million leprosy cases have been recorded and more than 200,000 new cases were registered each year, indicating that the disease is still progressing without hindrance. M. leprae, an intracellular bacterium, infects the Schwann cells of the peripheral nervous system. Several types of leprosy have been described, including indeterminate, tuberculoid, borderline tuberculoid, mid-borderline, borderline lepromatous and lepromatous, and three different forms of leprosy reactions, namely type 1, 2 and 3, have been designated. Microscopic detection, serological diagnostic test, polymerase chain reaction and flow tests are employed in the diagnosis of leprosy. The recommended treatment for leprosy consists of rifampicin, dapsone, clofazimine, ofloxacin and minocycline and vaccines are also available. However, relapse may occur after treatment has been halted and hence patients must be educated on the signs of relapse to allow proper treatment and reduce severity. In this review, we depict the current understanding of M. leprae pathogenicity, clinical aspects and manifestations. Transmission of leprosy, diagnosis and treatment are also discussed.

Association between NDO-LID and PGL-1 for leprosy and class I and II human leukocyte antigen alleles in an indigenous community in Southwest Amazon

The frequencies of the Human leukocyte antigen (HLA) alleles in the Puyanawa indigenous reserve population and their association with the NDO-LID and ELISA PGL-1 rapid serological test was assessed. This was a cross-sectional study with an epidemiological clinical design conducted in two indigenous communities in the state of Acre, Brazil. Blood was collected in a tube with EDTA to identify HLA alleles and perform serological tests. DNA was obtained using the salting out procedure. The LabType™ technique (One-Lambda-USA) was used for HLA class I (loci A*, B* and C*) and II (loci DRB1*, DQA1* and DQB1*) typing. Allele frequency was obtained by direct count, and the chi-square test was used to assess the association with the NDO-LID and PGL-1 tests. The most frequent alleles in the two communities were: HLA-A*02:01, HLA-B*40:02, HLA-DRB1*16:02, HLA-DQA1*05:05 and HLA-DQB1*03:01. The allele HLA-C*04:01 was the most common in the Barão community, and the allele HLA-C*07:01 in Ipiranga. Among individuals who presented seropositivity to the NDO-LID test, the association with alleles HLA-A*02 (43.18% vs 24.8%, p = 0.03, OR = 2.35) and HLA-B*53 (6.83% vs 0.0%, p = 0.03, OR = 8.95) was observed in the Barão community. HLA-B*15 was associated with non-seroconversion to the NDO-LID test in Ipiranga. In both communities, HLA-B*40 and HLA-C*03 were associated with positive serological response to ELISA PGL-1. The HLA class I and II alleles most frequently found in this study have already been described among Terena indigenous groups, and HLA class I contributes to seroconversion to NDO-LID and PGL-1 tests in inhabitants of the Barão and Ipiranga communities(AU).

Leprosy surveillance study in a highly endemic Brazilian area using leprosy specific serologic tests and IFNγ whole blood assay.

This surveillance study evaluated leprosy-serologic tests and the IFNγ whole-blood-assay/WBA as adjunct diagnostic tools. Previously diagnosed leprosy index cases, intradomiciliary, peridomiciliary contacts from a Brazilian endemic area were enrolled during domiciliary visits. Physical evaluation was performed by trained nurses and leprosy diagnosis confirmed by expert dermatologist. ELISA detected IgM anti-PGL-I, IgG anti-LID-1, and IgM/IgG anti-ND-O-LID antibodies. Heparinized WBA plasma stimulated with LID-1, 46f + LID-1, ML0276 + LID-1 (24 h, 37 °C, 5% CO2) was tested for human IFNγ (QuantiFERON®-TB Gold/QFT-G; Qiagen). The survey included 1731 participants: 44 leprosy index cases, 64 intradomiciliary, 1623 peridomiciliary contacts. Women represented 57.7%, median age was 32 years, 72.2% had BCG scar. Leprosy prevalence was higher in intradomiciliary (8.57%) versus peridomiciliary contacts (0.67%), p < 0.001. Among 23 suspects, five leprosy cases were confirmed: 4 multibacillary/MB and 1 paucibacillary/PB. Leprosy incidence was 0.30%: 1.56% in intradomiciliary versus 0.25% in peridomiciliary (p = 0.028). Seropositivity rates were 1.9% to PGL-I, 4.9% to LID-1, and 1.0% to ND-O-LID. LID-1 positivity was higher in all groups; incident cases were LID-1 seropositive. ND-O-LID positivity was higher in intra- versus peridomiciliary contacts (p = 0.022). IFNγ WBA (40 index cases, 19 suspects, 35 intradomiciliary, 74 peridomiciliary contacts) showed higher LID-1/WBA positivity in peridomiciliary contacts (p > 0.05); significant differences among groups were seen with 46f + LID-1 but 0276 + LID-1 induced higher IFNγ levels. Incident cases were LID-1 seropositive, while IFNγ-WBA had marginal diagnostic application. As seropositivity indicates exposed individuals at higher risk of disease development, the utility of serologic screening for surveillance and prophylactic measures remains to be demonstrated.

Diagnostic accuracy of tests using recombinant protein antigens of Mycobacterium leprae for leprosy: A systematic review.

The aim of this systematic review was to investigate the studies that evaluated the sensitivity and specificity of serologic tests using recombinant protein antigens from Mycobacterium leprae for leprosy diagnosis. We included 13 studies that were available in PubMed, Brazilian Virtual Library of Health, Web of Science, ScienceDirect and Scopus. From these studies, we found that the recombinant serine-rich 45-kDa protein of M. leprae (ML0411) demonstrated high performance for multibacillary (MB) also to paucibacillary (PB) patients, although this study was tested only for Indian population. Despite that, studies using the ND-O-LID antigen have been able to more accurately identify new cases of leprosy among people living in endemic or non-endemic areas and household contacts in Brazil, Colombia, and the Philippines, especially when combined with other biomarkers. Finally, low sensitivity values for PB patients' antibodies response remain challenging for tests intended to diagnose clinical forms that comprise this classification in leprosy.

[The use of synthetic glycoconjugates as components of the immunochromatographic test for rapid serological diagnosis of leprosy.]

The glycoconjugates with BSA (bovine serum albumin) were synthesized using a next saccharide: disaccharide derivative M.leprae PGL-1 (phenolic glycolipid-1); a complex of the disaccharide fragment and the branched hexasaccharide fragment LAM (lipoarabinomannan); diarabinofuranose fragment LAM. These glycoconjugates were used as antigenic components for leprosy rapid serotest construction in immunochromatographic format (leprosy LF serotest). The data obtained with sera of leprosy patients, patients who have been in contact with leprosy, and healthy donors indicate that the most promising antigenic component is a BSA conjugate with two synthetic epitopes - a disaccharide derivative of PGL-1 and a branched hexasaccharide fragment of LAM. The leprosy LF serotest with such glycoconjugate demonstrated the greatest diagnostic sensitivity for main forms of leprosy - paucibacillary (PB) and multibacillary (MB).

Cell-mediated and serology-based tests for Mycobacterium ulcerans disease: A systematic review and meta-analysis.

Buruli ulcer (BU) is a subcutaneous necrotic infection of the skin caused by Mycobacterium ulcerans. It is the third most common human mycobacterial disease after tuberculosis (TB) and leprosy. The available methods for detection of the bacilli in lesions are microscopic detection, isolation and cultivation of the bacterium, histopathology, and polymerase chain reaction (PCR). These methods, although approved by the World Health Organization (WHO), have infrastructural and resource challenges in medical centres and cell-mediated immunity (CMI) and/or serology-based tests have been suggested as easier and more appropriate for accurate assessment of the disease, especially in remote or underdeveloped areas. This study systematically reviewed and conducted a meta-analysis for all research aimed at developing cell-mediated immunity (CMI) and/or serology-based tests for M. ulcerans disease. Information for this review was searched through PubMed and Web of Science databases and identified up to June 2019. References from relevant articles and reports from the WHO Annual Meeting of the Global Buruli Ulcer Initiative were also used. Twelve studies beginning in 1952, that attempted to develop CMI and/or serology-based tests for the disease were identified. These studies addressed issues of specificity and sensitivity in context of antigen composition as well as study heterogeneity and bias. The two main types of antigenic preparations considered were pathogen-derived and recombinant protein preparations. There was slight difference in test performance when M. ulcerans recombinant proteins [positivity: 67.5%; 32.5%] or pathogen-derived [positivity: 76.0%; 24.0%] preparations were used as test antigens among BU patients. However, pathogen-derived preparations were better at differentiating between patients and control groups [odds ratio (OR) of 27.92, 95%CI: 5.05-154.28]. This was followed by tests with the recombinant proteins [OR = 1.23, 95%CI: 0.27-5.62]. Overall, study heterogeneity index, I2 was 92.4% (p = 0.000). It is apparent from this review that standardisation is needed in any future CMI and/or serology-based tests used for M. ulcerans disease.

Utility and limitations of serodiagnostic tests in monitoring the response to treatment of leprosy patients.

Simple measures that can facilitate early recognition of leprosy complications are still lacking. We therefore evaluated a lateral flow-based rapid diagnostic test and fast enzyme-linked immunosorbent assay measuring anti-LID-NDO antibody responses among leprosy cases in Cebu, Philippines. Responses were measured at diagnosis, then during and after the provision of standard multidrug therapy. Our data indicate that both platforms are highly sensitive tools for the primary diagnosis of, in particular, multibacillary leprosy. A gradual, quantifiable decline in both magnitude of response and percent positive responders was observed during and after treatment. As a group, patients that developed erythema nodosum leprosum (ENL) had a significantly higher response at diagnosis than patients that either developed reversal reactions or did not develop reactions. Although higher initial anti-NDO-LID responses were a risk factor for ENL, neither platform, however, could reliably predict the time of emergence of reactional episodes.

Fatores associados à hanseníase em crianças contatos de adultos notificados em uma região endêmica do Centro-Oeste do Brasil / Factors associated with leprosy in children contacts of notified adults in an endemic region of Midwest Brazil

Objetivos: Analisar os fatores associados à hanseníase em crianças contatos intradomiciliares de adultos notificados com a doença em município endêmico, Mato Grosso, Brasil. Método: Estudo caso-controle com 204 menores de 15 anos residentes em um município endêmico. Consideraram-se casos (n = 40) crianças registradas com hanseníase no Sistema Nacional de Agravos de Notificação em 2014 e 2015 e que eram contatos intradomiciliares de pelo menos um adulto diagnosticado com a doença na família e como grupo controle (n = 164) crianças residentes a um raio de 100 metros dos casos notificados. Os dados foram obtidos por meio de análise de prontuários, entrevistas e coleta de amostras de sangue para investigação sorológica do anti-PGL-I pelo método Elisa. Usou-se a técnica de regressão logística binária e p ≤ 0,05. Resultados: Mostraram-se associados à hanseníase após ajustes: idade (IC 95%: 1,24-9,39; p = 0,018), zona de residência (IC 95%: 1,11-6,09; p = 0,027), destino de lixo (IC 95%: 1,91-27,98; p = 0,004), história da doença na família (IC 95%: 3,41-22,50; p = 0,000) e tempo de moradia (IC 95%: 1,45-7,78; p = 0,005). Conclusão: Os fatores associados à doença indicam maior vulnerabilidade em menores de 8 a 14 anos, ligadas as condições e ao tempo de moradia, bem como a história da doença na família(AU).

Objectives:To analyze the factors associated with leprosy in children who were intradomiciliary contacts of notified adults with the disease in an endemic municipality in Mato Grosso, Brazil. Method: Case-control study with 204 children under 15 years of age, living in an endemic municipality. Cases (n = 40) were considered as the children with leprosy registered at the National Information System of Notifiable Diseases in 2014 and 2015, who were intradomiciliary contacts of at least one adult diagnosed with the disease in the family, and as a control group (n = 164) of children living within a radius of up to 100 m of the notified cases. Data were obtained through medical file analysis, interviews, and blood samples for anti-PGL-I serological test by the ELISA method. The binary logistic regression technique was used, with p ≤ 0.05. Results: After adjustments, the following were associated with leprosy: age (95% CI: 1.24-9.39, p = 0.018), area of residence (95% CI: 1.11-6.09, p = 0.027), waste disposal (95% CI: 1.91-27.98, p = 0.004), family history of the disease (95% CI: 3.41-22.50, p = 0.000), and time of residence (95% CI: 1.45-7.78, p = 0.005). Conclusion: Factors associated with the disease indicate greater vulnerability of children aged 8-14 years, associated with living conditions and time of residence, as well as the family history of the disease(AU).

Prospects for new leprosy diagnostic tools, a narrative review considering ELISA and PCR assays

Abstract Slit skin smear and histopathological examinations are currently the main laboratory tools used to aid the diagnosis of leprosy. However, their sensitivity is low, and many cases are not detected. New methodologies have been studied to develop more accurate tests. This narrative review aims to raise attention to the results of molecular (polymerase chain reaction) and serological (Enzyme-Linked Immunosorbent Assay) tests applied to the diagnosis of leprosy, and to summarize the available information about the former. Original scientific articles published in indexed international journals, whose study involved aspects of the diagnosis and classification of leprosy cases or home contacts, were selected. The data were extracted independently using a standardized method that dictated the inclusion of the following information: diagnosis in Paucibacillary and Multibacillary cases and in household contacts; sample number; sample type; study design; studied variables; statistical analysis employed; main results; and limitations identified. In clinical practice, the results from molecular and serological tests are assessed separately, with moderate sensitivity and specificity. However, an integrated study of these methodologies has been suggested for greater accuracy in diagnosis.

Leprosy: prevalence and factors associated with seropositivity for anti-NDO-LID antibodies in children under 15 years of age.

BACKGROUND: A high prevalence of leprosy among children under 15 years of age indicates the need to implement actions to prevent new cases of the disease. Serological tests have been developed with the aim of helping to control the disease by indicating, through seropositivity, the presence of infection. OBJECTIVE: To analyze the prevalence and factors associated with seropositivity rate for anti-NDO-LID antibodies in children under 15 years of age, contacts of leprosy patients. METHOD: We performed a cross-sectional study with 210 children under 15 years old of age. Of them, 50 were household contacts and 160 were neighborhood contacts living in the municipality of Cuiabá, state of Mato Grosso, in 2016. The data were obtained from interviews and the NDO-LID rapid test during home visits from February to July 2016. For the analysis, we used Poisson regression and prevalence ratio. RESULTS: Seropositivity in contacts was 6.2%. Variables associated with seropositive tests included sex (PR = 1.05; 95% CI: 1.01 - 1.08), race/skin color (PR = 0.95; 95% CI: 0.90 - 0.99), residence area (PR = 1.05; 95% CI: 1.01 - 1.09), and number of people per household (PR = 1.06; 95% CI: 1.02 - 1.08). STUDY LIMITATIONS: The small sample size, besides leading to wide confidence intervals, may have been a limitation for the identification of associated factors. CONCLUSIONS: The prevalence of seropositivity was high. Variables associated with NDO-LID seropositivity included female sex, not to be brown skinned, live in urban areas, and live with five or more people.

A rapid diagnostic test for human Visceral Leishmaniasis using novel Leishmania antigens in a Laser Direct-Write Lateral Flow Device.

ABSTRACT Visceral Leishmaniasis (VL) causes high morbidity and mortality in low-to-middle-income countries worldwide. In this study, we used Laser Direct-Write (LDW) technology to develop a new Lateral Flow Device (LFD) with double-channel geometry on a low-cost paper platform as a rapid and accurate serodiagnostic assay for human VL. This Duplex VL-LFD was based on a laser-patterned microfluidic device using two recombinant Leishmania proteins, ß-tubulin and LiHyp1, as novel diagnostic antigens. The VL-LFD assay was tested with blood/serum samples from patients diagnosed with VL, Tegumentary Leishmaniasis, Leishmaniasis of unknown identity, other parasitic diseases with similar clinical symptoms, i.e. Leprosy Disease and Chagas Disease, and blood from healthy donors, and compared in parallel with commercial rK39 IT-LEISH® Kit. Clinical diagnosis and real-time Polymerase Chain Reaction assay were used as reference standards. VL-LFD Sensitivity (S ± 95% Confidence Intervals (CI)) of 90.9 (78.9-100) and Specificity (Sp ± 95% CI) of 98.7 (96.1-100) outperformed the IT-LEISH® Kit [S = 77.3 (59.8-94.8), Sp = 94.7 (89.6-99.8)]. This is the first study reporting successful development of an LFD assay using the LDW technology and the VL-LFD warrants comparative testing in larger patient cohorts and in areas with endemic VL in order to improve diagnosis and disease management.

Leprosy: prevalence and factors associated with seropositivity for anti-NDO-LID antibodies in children under 15 years of age

Abstract: Background: A high prevalence of leprosy among children under 15 years of age indicates the need to implement actions to prevent new cases of the disease. Serological tests have been developed with the aim of helping to control the disease by indicating, through seropositivity, the presence of infection. Objective: To analyze the prevalence and factors associated with seropositivity rate for anti-NDO-LID antibodies in children under 15 years of age, contacts of leprosy patients. Method: We performed a cross-sectional study with 210 children under 15 years old of age. Of them, 50 were household contacts and 160 were neighborhood contacts living in the municipality of Cuiabá, state of Mato Grosso, in 2016. The data were obtained from interviews and the NDO-LID rapid test during home visits from February to July 2016. For the analysis, we used Poisson regression and prevalence ratio. Results: Seropositivity in contacts was 6.2%. Variables associated with seropositive tests included sex (PR = 1.05; 95% CI: 1.01 - 1.08), race/skin color (PR = 0.95; 95% CI: 0.90 - 0.99), residence area (PR = 1.05; 95% CI: 1.01 - 1.09), and number of people per household (PR = 1.06; 95% CI: 1.02 - 1.08). Study Limitations: The small sample size, besides leading to wide confidence intervals, may have been a limitation for the identification of associated factors. Conclusions: The prevalence of seropositivity was high. Variables associated with NDO-LID seropositivity included female sex, not to be brown skinned, live in urban areas, and live with five or more people.