Neurological aspects of HTLV-1 infection: symptoms in apparently asymptomatic carriers.

Human T-lymphotropic virus type 1 (HTLV-1) is classically associated with the HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), although the mechanisms of this neurological disorder remain unclear. In addition, some patients who develop "minor" neurological signs that do not meet diagnostic criteria for HAM/TSP are classified as asymptomatic carriers. This study aims to demonstrate the neurological symptoms of Brazilian patients living with HTLV-1 classified as not-HAM.TSP. This observational study evaluated patients treated in an HTLV reference center in Bahia, Brazil, between February 2022 and July 2023. The data were obtained through the analysis of medical records and neurological consultation. Those individuals classified as HAM/ TSP were excluded from this study. 74 patients were submitted to a careful neurological evaluation: 23 HAM/TSP, 22 were classified with intermediate syndrome (IS), and 29 were oligosymptomatic. Self-reported symptoms were significantly more common in the IS group, including urinary symptoms such as nocturia, urgency, incontinence, dysuria, weakness, paresthesia, lumbar pain, xerostomia, and xerophthalmia. Physical examination findings consistent with reduced vibratory and tactile sensitivity were more common in the IS group (p = 0.017 and p = 0.013). Alterations in the V and VIII cranial nerves were present in both groups. HTLV-1 can lead to the development of important neurological signs and symptoms in apparently asymptomatic individuals. This data highlights the need for more research into the neurological aspects of HTLV-1 infection and emphasizes the importance of early diagnosis, treatment, and support for individuals living with this virus.

HTLV-1 cell-free DNA in plasma as a potential biomarker in HTLV-1 carriers and adult T-cell leukemia-lymphoma.

Viral cell-free DNA (cfDNA) in plasma has been widely evaluated for detecting cancer and monitoring disease in virus-associated tumors. We investigated whether the amount of cfDNA of human T-cell leukemia virus type 1 (HTLV-1) correlates with disease state in adult T-cell leukemia-lymphoma (ATL). HTLV-1 cfDNA in aggressive ATL was significantly higher than that in indolent ATL and asymptomatic carriers. Notably, patients with lymphoma type represented higher HTLV-1 cfDNA amount than chronic and smoldering subtypes, though they had no abnormal lymphocytes in the peripheral blood. HTLV-1 cfDNA can be a universal biomarker that reflects the expansion of ATL clones.

Investigating the effect of MAP2K1 gene (MEK1) in MAPK pathway in the induction of adult T-cell leukemia/lymphoma (ATLL).

Background and Objectives: HTLV-1 is responsible for two important diseases, HAM/TSP and ATLL. Approximately 10 to 20 million people are infected with HTLV-1 worldwide. Identifying altered genes in different cancers is crucial for finding potential treatment strategies. One of the proteins of the RAS/MAPK signaling pathway is MEK1, which is made from the MAP2K1 gene. The effects of the MAP2K1 gene on the MAPK signaling pathway are not yet fully elucidated. The current study aims to determine the MAP2K1 gene mutations and the level of MAP2K1 gene expression in ATLL patients compared to healthy individuals. Materials and Methods: Ten ATLL and 10 healthy control individuals were investigated in this study. We used ELISA test to screen anti-HTLV-I antibodies and PCR for confirmation of infection. Then, we extracted total RNA from fresh whole blood, and cDNA was synthesized. The expression levels of the MAP2K1 gene were examined by qRT-PCR, and to check possible mutations in the MAP2K1 gene; all samples were sequenced and analyzed by BioEdite Software. Results: MAP2K1 gene expression in the ATLL group was significantly higher than in the healthy control (P=0.001). The mutational sequencing analysis showed nucleotide 212 (S→R) change and identification mutations at different nucleotides that were entirely different from the nucleotide mutations defined in the UniProt database. Conclusion: These results could be a perspective in the prevention, prognosis, and targeted treatment of diseases in which the MAP2K1 gene plays a vital role.

Signs and symptoms of human T-lymphotropic virus 1 and 2 infections in paediatric patients.

OBJECTIVE: To determine the prevalence of signs and symptoms of HTLV-1 and 2 infection in paediatric patients. METHODS: We included cohort, case-control and descriptive observational studies that reported the prevalence of signs and symptoms of HTLV-1 and 2 infections in paediatric patients. Searches were performed in MEDLINE® (Ovid), EMBASE and LILACS from inception to the present, and we saturated information with other sources of published and unpublished literature. We decided not to perform meta-analysis according to heterogeneity. RESULTS: A total of eight studies met the inclusion criteria for qualitative analysis. No studies of HTLV-2 were found. Females predominated and there was vertical transmission in nearly 100% of cases. Infective dermatitis was a common manifestation of HTLV in paediatric patients. In addition, persistent hyperreflexia, clonus and the Babinski sign were early neurological alterations observed in patients carrying the virus. CONCLUSION: HTLV screening is recommended in patients presenting infective dermatitis, persistent hyperreflexia, walking disturbances and in those who come from endemic zones.

Impact of COVID-19 Pandemic on Seroprevalence of HIV, HBV, HCV and HTLV I-II in a Blood Bank in Medellín, Colombia, 2019-2022.

The objective of this research was to analyze the impact of the COVID-19 pandemic on seroprevalence of HIV, HBV, HCV and HTLV I-II in donors from a blood bank in Medellin, Colombia, 2019-2022. A cross-sectional analytical study was carried out with three groups: pre-pandemic with 14,879 donors; preventive isolation with 9035; and selective isolation + new normality with 26,647 subjects. Comparisons were made with Chi2 and Bonferroni adjustment, Kruskal-Wallis' H with Dunnett's post-hoc, prevalence ratios, and multivariate logistic regression. COVID-19 decreased donations of men, altruistic and repetitive donors, and increased the age of donors. HIV increased with the COVID-19 pandemic, while HBV, HCV, and HTLV I-II decreased. The pandemic had an independent effect on these viral infections. These findings constitute an alert about what may be happening in the general population and show the importance of improving epidemiological surveillance and the investigation of these infections.

Human T-cell leukaemia virus type 1 and Adult T-cell leukaemia/lymphoma in Queensland, Australia: a retrospective cross-sectional study.

OBJECTIVES: Human T-cell leukaemia virus type 1 (HTLV-1), an STI, is reported to be highly prevalent in Indigenous communities in Central Australia. HTLV-1 is an incurable, chronic infection which can cause Adult T-cell leukaemia/lymphoma (ATL). ATL is associated with high morbidity and mortality, with limited treatment options. We studied the prevalence of HTLV-1 and ATL in the state of Queensland, Australia. METHODS: Serum samples stored at healthcare services in Brisbane, Townsville and Cairns and at haemodialysis units in Brisbane (2018-2019) were screened for HTLV-1/2 antibodies using the Abbott ARCHITECT chemiluminescent microparticle immunoassay (CMIA) for antibodies against gp46-I, gp46-II and GD21 (Abbott CMIA, ARCHITECT). Reactive samples were confirmed through Western blot. Pooled Australian National Cancer Registry surveillance data reporting on cases coded for ATL (2004-2015) were analysed. RESULTS: Two out of 2000 hospital and health services samples were confirmed HTLV-1-positive (0.1%, 95% CI 0.02% to 0.4%), both in older women, one Indigenous and one non-Indigenous. All 540 haemodialysis samples tested negative for HTLV. All samples were HTLV-2-negative. Ten out of 42 (24.8%) reported cases of ATL in Australia were from Queensland (crude incidence rate 0.025/100 000; 95% CI 0.011 to 0.045); most cases were seen in adult men of non-Indigenous origin. Nineteen deaths due to ATL were recorded in Australia. CONCLUSION: We confirm that HTLV-1 and ATL were detected in Queensland in Indigenous and non-Indigenous people. These results highlight the need for HTLV-1 prevalence studies in populations at risk of STIs to allow the implementation of focused public health sexual and mother-to-child transmission prevention strategies.

HTLV-I associated bronchioloalveolar disorder (HABA): disease concept and differential diagnosis of an unsolved disease entity.

INTRODUCTION: Human T-cell leukemia virus type 1 (HTLV-I) associated bronchioloalveolar disorder (HABA) is a chronic and progressive bronchiolar/alveolar disorder related to HTLV-1 infection. Clinical knowledge and guidance are lacking for the diagnosis and management of this condition. AREAS COVERED: This work aimed to review the latest information and challenges regarding HABA diagnosis and treatment. EXPERT OPINION: HABA is an immune-mediated state induced by HTLV-1. For diagnosis of HABA, other infectious diseases and pulmonary infiltration of adult T-cell leukemia should be excluded by investigations such as computed tomography (CT), transbronchial biopsy, and bronchoalveolar lavage fluid (BALF) analysis. Typical CT findings in HABA include diffuse panbronchiolitis-like or bronchiectasis patterns, whereas cases with other abnormalities, including interstitial pneumonia, have also been reported. A high rate of polyclonal CD4+ and CD25+ lymphocytes is detected in BALF of patients with HABA, reflecting the infiltration of HTLV-1 infected T-cells in the lung. Current treatment options are not HABA specific, and include corticosteroids, macrolide antibiotics, and pirfenidone. Mitigation of the adverse effects of HTLV-1 infection requires the establishment of diagnostic criteria for the disease, screening programs for HABA in HTLV-1 infected individuals, and the development of effective disease treatment strategies.

Dynamics of HIV-1/HTLV-I Co-Infection Model with Humoral Immunity and Cellular Infection.

Human immunodeficiency virus type 1 (HIV-1) and human T-lymphotropic virus type I (HTLV-I) are two retroviruses which infect the same target, CD4+ T cells. This type of cell is considered the main component of the immune system. Since both viruses have the same means of transmission between individuals, HIV-1-infected patients are more exposed to the chance of co-infection with HTLV-I, and vice versa, compared to the general population. The mathematical modeling and analysis of within-host HIV-1/HTLV-I co-infection dynamics can be considered a robust tool to support biological and medical research. In this study, we have formulated and analyzed an HIV-1/HTLV-I co-infection model with humoral immunity, taking into account both latent HIV-1-infected cells and HTLV-I-infected cells. The model considers two modes of HIV-1 dissemination, virus-to-cell (V-T-C) and cell-to-cell (C-T-C). We prove the nonnegativity and boundedness of the solutions of the model. We find all steady states of the model and establish their existence conditions. We utilize Lyapunov functions and LaSalle's invariance principle to investigate the global stability of all the steady states of the model. Numerical simulations were performed to illustrate the corresponding theoretical results. The effects of humoral immunity and C-T-C transmission on the HIV-1/HTLV-I co-infection dynamics are discussed. We have shown that humoral immunity does not play the role of clearing an HIV-1 infection but it can control HIV-1 infection. Furthermore, we note that the omission of C-T-C transmission from the HIV-1/HTLV-I co-infection model leads to an under-evaluation of the basic HIV-1 mono-infection reproductive ratio.

Evolución clínica de la uveítis intermedia asociada a infección por el virus linfotrópico de células T humano tipo 1 (HTLV-1) / Clinical course of HTLV-1 infection associated intermediate uveitis

Objetivo: Describir las características asociadas a la presentación, tratamiento y seguimiento de una serie de casos de uveítis intermedia asociada al virus linfotrópico de células T humano de tipo 1 (HTLV-1).Pacientes y métodosEstudio retrospectivo, descriptivo y longitudinal. Se incluyó a pacientes con uveítis intermedia asociada a infección por HTLV-1 atendidos en una clínica oftalmológica de referencia de Lima (Perú), durante 2012-2018.ResultadosSe incluyó a 18 pacientes (28 ojos). La edad promedio a la presentación fue de 57,3 años; el 66,6% fueron mujeres. El tiempo de seguimiento promedio fue de 1.280 días. Los síntomas más frecuentes fueron visión borrosa o disminuida (78,6%) y visión de cuerpos flotantes (57,1%). La agudeza visual mejor corregida fue de 20/40 o mejor en el 53,6%. La presión intraocular inicial promedio fue de 14,95mmHg. Se observaron precipitados retroqueráticos en el 50% de ojos, siendo el tipo más frecuente el espiculado (17,9% de los ojos). El tratamiento más frecuente fue la inyección periocular de corticoides (en el 53,6% de los ojos). Se presentaron complicaciones como membrana epimacular (50%), catarata (21,4%) y glaucoma (7,1%). Al final del seguimiento, solo 2 ojos perdieron una línea de visión; la agudeza visual mejor corregida final fue de 20/40 o mejor en el 85,7%, y de 20/70 o mejor en el 96,4%. Los pacientes afectados en ambos ojos aumentaron de 33% a la presentación a 55,5%. El curso de la enfermedad fue crónico en el 60,7%.ConclusiónLa uveítis intermedia asociada a infección por HTLV-1 se presentó principalmente en la segunda mitad de la vida, con curso crónico y buen pronóstico visual. (AU)

Objective: To describe the clinical features at presentation, delivered treatment and follow-up of a case series of human T-cell lymphotropic virus type 1 (HTLV-1) associated intermediate uveitis.Patients and methodsRetrospective, descriptive and longitudinal study of patients with HTLV-1 associated intermediate uveitis treated at a reference ophthalmology facility in Lima, Peru, during the years 2012 to 2018.ResultsA total of 18 patients (28 eyes) were included, the average age at presentation was 57.3 years, 66.6% were women, and the average follow-up time was 1,280 days. The most frequent symptoms were blurred or diminished vision (78.6%) and floaters (57.1%). Best corrected visual acuity was 20/40 or better in 53.6%. The mean initial intraocular pressure was 14.95mmHg. Keratic precipitates were observed in 50% of eyes, 17.9% were of the stellate type. The most frequent treatment was periocular corticosteroid injections (53.6%). Complications such as epimacular membrane (50%), cataract (21.4%) and glaucoma (7.1%) occurred. At the end of follow-up, only 2 eyes lost one line of vision; the final best corrected visual acuity was 20/40 or better in 85.7%, and 20/70 or better in 96.4%. Patients with both eyes affected increased from 33% at presentation to 55.5%. The course of the disease was chronic in 60.7%.ConclusionHTLV-1 associated intermediate uveitis mainly occurred in patients in the second half of life, developing a chronic course and with good visual prognosis. (AU)

HTLV, a multi organ oncovirus.

Human T lymphotropic virus (HTLV-I) is a retrovirus that has been recognized as a causative agent of two crucidal diseases, HTLV-I-Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP) and Adult T cell Leukemia-Lymphoma (ATLL). The virus not only induces those diseases in a small proportion of HTLV-I carriers (3-5%) but also it is associated with other diseases such as HTLV-I-Associated Arthropathy (HAAP), Cutaneous T Cell Lymphoma (CTCL), Graves' disease, uveitis, polymyositis, chronic respiratory diseases, lymphadenitis and dermatitis. Furthermore, HTLV related and accelerated disorders were more investigated, and the factors that might implicate in the development or progression of diseases have been discussed. We founded 13 categories of non-associated disease in studies such as Reproductive Disorders, Coronary Artery Disease (CAD), non -ATLL lymphoma, Co-infection, non-HAM/TSP neurological associated disease, non ATLL cutaneous associated disease, Autoimmune-Inflammatory related disease, Kidney disease, Liver disease, Respiratory disease, TB disease and Thyroid disease. With regard to the reviewed studies suggested HTLV-I disorders can divide into three manifests; related, accelerated and associated disease. However, interaction between HTLV-I infection and host immune response was complicated and vague. Some infectious patients indicated the involvement of inflammatory response of immune system, but in other individuals function of anti-inflammatory elements was observed. For a better understanding of this classification, more systematic studies should be designed and need to provide a global network to control and prevent HTLV affiliated diseases.

Clinical course of HTLV-1 infection associated intermediate uveitis.

OBJECTIVE: To describe the clinical features at presentation, delivered treatment and follow-up of a case series of human T-cell lymphotropic virus type 1 (HTLV-1) associated intermediate uveitis. PATIENTS AND METHODS: Retrospective, descriptive and longitudinal study of patients with HTLV-1 associated intermediate uveitis treated at a reference ophthalmology facility in Lima, Peru, during the years 2012 to 2018. RESULTS: A total of 18 patients (28 eyes) were included, the average age at presentation was 57.3 years, 66.6% were women, and the average follow-up time was 1,280 days. The most frequent symptoms were blurred or diminished vision (78.6%) and floaters (57.1%). Best corrected visual acuity was 20/40 or better in 53.6%. The mean initial intraocular pressure was 14.95 mmHg. Keratic precipitates were observed in 50% of eyes, 17.9% were of the stellate type. The most frequent treatment was periocular corticosteroid injections (53.6%). Complications such as epimacular membrane (50%), cataract (21.4%) and glaucoma (7.1%) occurred. At the end of follow-up, only 2 eyes lost one line of vision; the final best corrected visual acuity was 20/40 or better in 85.7%, and 20/70 or better in 96.4%. Patients with both eyes affected increased from 33% at presentation to 55.5%. The course of the disease was chronic in 60.7%. CONCLUSION: HTLV-1 associated intermediate uveitis mainly occurred in patients in the second half of life, developing a chronic course and with good visual prognosis.

Linfoma gástrico primario de células T, no asociado a HTLV-1, con metástasis cutánea y neumoperitoneo / Non-HTLV-1-associated primary gastric T-cell lymphoma with cutaneous metastasis and pneumoperitoneum

Introducción: Los linfomas gástricos primarios representan menos del 5% de los linfomas no Hodgkin (LNH). La gran mayoría de linfomas gástricos primarios son linfomas de células B de alto grado. Los linfomas gástricos primarios de células T son muy raros y usualmente se asocian a infección por HTLV-1 en regiones endémicas. Material y método. Describimos el caso de una paciente mujer de mediana edad que se presentó con neumoperitoneo debido a ulcera gástrica perforada, síndrome consuntivo y lesiones cutáneas y orales. Resultados. La histopatología e inmunohistoquímica confirmaron linfoma gástrico primario de células T con compromiso cutáneo. La serología para HTLV-1, virus del Epstein-Barr y VIH fueron negativas. Conclusión. La finalidad de este reporte es dar a conocer esta forma de presentación sumamente rara de linfoma gástrico primario.

Background: Primary gastric lymphomas account for less than5%ofnon-Hodgkinlymphomas(NHL).Thevast majority of primary gastric lymphomas are high-grade B-cell lymphomas. Primary gastric T-cell lymphomas are very rare and are usually associated with HTLV-1 infection in endemic regions. We describe Material and methods.the case of a middle-aged female patient who presented with pneumoperitoneum due to a perforated gastric ulcer, wasting syndrome, and skin and oral lesions. . Results: Histopathology and immunohistochemistry confirmed primary gastric T-cell lymphoma with skin involvement. The serologyfor HTLV-1,Epstein-Barr virus and HIVwere negative. The aim of this report is to present Conclusion: this extremely rare presentation of primary gastric lymphoma

Stability analysis of general delayed HTLV-I dynamics model with mitosis and CTL immunity.

This paper formulates and analyzes a general delayed mathematical model which describe the within-host dynamics of Human T-cell lymphotropic virus class I (HTLV-I) under the effect Cytotoxic T Lymphocyte (CTL) immunity. The models consist of four components: uninfected CD$ 4^{+} $T cells, latently infected cells, actively infected cells and CTLs. The mitotic division of actively infected cells are modeled. We consider general nonlinear functions for the generation, proliferation and clearance rates for all types of cells. The incidence rate of infection is also modeled by a general nonlinear function. These general functions are assumed to be satisfy some suitable conditions. To account for series of events in the infection process and activation of latently infected cells, we introduce two intracellular distributed-time delays into the models: (ⅰ) delay in the formation of latently infected cells, (ⅱ) delay in the activation of latently infected cells. We determine a bounded domain for the system's solutions. We calculate two threshold numbers, the basic reproductive number $ R_{0} $ and the CTL immunity stimulation number $ R_{1} $. We determine the conditions for the existence and global stability of the equilibrium points. We study the global stability of all equilibrium points using Lyapunov method. We prove the following: (a) if $ R_{0}\leq 1 $, then the infection-free equilibrium point is globally asymptotically stable (GAS), (b) if $ R_{1}\leq 1 < R_{0} $, then the infected equilibrium point without CTL immunity is GAS, (c) if $ R_{1} > 1 $, then the infected equilibrium point with CTL immunity is GAS. We present numerical simulations for the system by choosing special shapes of the general functions. The effects of proliferation of CTLs and time delay on the HTLV-I progression is investigated. We noted that the CTL immunity does not play the role in clearing the HTLV-I from the body, but it has an important role in controlling and suppressing the viral infection. On the other hand, we observed that, increasing the time delay intervals can have similar influences as drug therapies in removing viruses from the body. This gives some impression to develop two types of treatments, the first type aims to extend the intracellular delay periods, while the second type aims to activate and stimulate the CTL immune response.

Prevalencia de marcadores infecciosos y factores asociados en donantes de un banco de sangre peruano / Prevalence of infection markers and associated factors in donors of a peruvian blood bank

RESUMEN Se buscó determinar la prevalencia de marcadores infecciosos en donantes de un banco de sangre en Perú y valorar si las variables sociodemográficas del donante se asocian con la presencia de estos marcadores. Se realizó un estudio transversal analítico en 5942 donantes de un banco de sangre durante el 2018. Se determinó la positividad a inmunodeficiencia humana (VIH), hepatitis B (VHB), hepatitis C (VHC) y HTLV I-II; además de sífilis y enfermedad de Chagas. La prevalencia de VIH fue 0,81%, VHB 6,19%, VHC 0,12%, HTLV I-II 0,66%, enfermedad de Chagas 2,76% y sífilis 1,73%. Diversos factores sociodemográficos se asociaron con la positividad de marcadores infecciosos. El tipo de donación predominante fue no voluntaria (96%) y el 53% presentó historia de donación previa. Las prevalencias de marcadores infecciosos de VIH, VHB, enfermedad de Chagas y sífilis en los donantes de sangre fueron altas comparadas con otros países de la región.

ABSTRACT We aimed to determine the prevalence of infection markers in donors of a Peruvian blood bank and to assess whether donor sociodemographic variables are associated with the presence of these markers. An analytical cross-sectional study was carried out in 5942 donors of a blood bank, whose data was collected during 2018. Positivity to human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) and HTLV I-II was determined, in addition to syphilis and Chagas disease. The prevalence of HIV was 0.81%; for HBV it was 6.19%; for HCV, 0.12%; for HTLV I-II, 0.66%; for Chagas disease, 2.76% and for syphilis it was 1.73%. Several sociodemographic factors were associated with infection markers positivity. The predominant donation type was non-voluntary (96%) and 53% had history of previous donation. The prevalence of infection markers for HIV, HBV, Chagas disease and syphilis in blood donors was high compared to other countries in the region.

Metaanálisis de la validez del inmunodiagnóstico del virus linfotrópico de células T humanas i/ii en bancos de sangre, 2000-2018 / Meta-analysis regarding the validity of the immunodiagnosis of human T-cell lymphotropic virus I/II in blood banks, 2000-2018 / Meta-análise da validade do imunodiagnóstico do vírus linfotrópico de células t humanas I/II em bancos de sangue, 2000-2018

Resumen Objetivo: Evaluar la validez del inmunodiagnóstico del htlv i/ii en bancos de sangre, con base en estudios publicados en la literatura científica. Metodología: Se efectuó un metaanálisis de pruebas diagnósticas siguiendo la guía prisma y las recomendaciones de Cochrane. Se evaluó la calidad metodológica con quadas y se garantizó la reproducibilidad y la exhaustividad. Se realizó también un análisis de efectos aleatorios para la sensibilidad, la especificidad, los cocientes de probabilidad, la razón de momios diagnóstica y la curva característica operativa del receptor (roc) con sus intervalos de confianza (ic) del 95 %. Resultados: Se tamizaron 4604 estudios, de los cuales solo tres cumplieron el protocolo. Se evaluaron 548 infectados con htlv i/ii y 6643 sanos. El inmunodiagnóstico de htlv i/ii presentó una sensibilidad del 99 % (ic95 % = 98,0-99,0), especificidad del 100 % (ic95 % = 99,9-100), cocientes de probabilidad positivo de 315,8 (ic95 % = 128,2-778,5) y negativo de 0,02 (ic95 % = 0,01-0,04), razón de momios diagnóstica de 24373 (ic95 % = 6864-86545) y área bajo la curva roc del 99,9 %. Conclusión: Se dispone de pocos estudios en este campo del inmunodiagnóstico htlv i/ii. El elevado número de sujetos analizados evidenció alta validez del inmunodiagnóstico, lo que resulta determinante para garantizar la inocuidad de las unidades de sangre, la detección de portadores asintomáticos, la disminución de la transmisión y el inicio de tratamiento.

Abstract Objective: To evaluate the validity of the immunodiagnosis of htlv i/ii in blood banks, based on studies published in the scientific literature. Methodology: A meta-analysis of diagnostic tests was carried out following the PRISMA guidelines and Cochrane recommendations. The methodological quality was evaluated with QUADAS, and reproducibility and completeness were guaranteed. A random effects analysis was also performed with respect to sensitivity, specificity, likelihood ratios, diagnostic odds ratio, and receiver operating characteristic curve (ROC) with their 95 % confidence intervals (CI). Results: 4,604 studies were screened, of which only three complied with the protocol. 548 subjects infected with HTLV I/II and 6,643 healthy subjects were evaluated. The immunodiagnosis of HTLV I/II had a sensitivity of 99 % (95 % CI = 98.0-99.0), a specificity of 100 % (95 % CI = 99.9-100), a positive likelihood ratio of 315.8 (95 % CI = 128.2-778.5) and a negative likelihood ratio of 0.02 (95 % CI = 0.01-0.04), a diagnostic odds ratio of 24,373 (95 % CI = 6,864-86,545), and an area under the ROC curve of 99.9 %. Conclusion: Few studies are available in the field of HTLV I/II immunodiagnosis. The high number of subjects analyzed showed high validity of the immunodiagnosis, which is decisive to guarantee the safety of the blood units, the detection of asymptomatic carriers, the decrease in transmission, and the start of treatment.

Resumo Objetivo: Avaliar a validade do imunodiagnóstico do HTLV I/II nos bancos de sangue, baseados nos estudos publicados na literatura científica. Metodologia: Foi realizada uma meta-análise de testes diagnósticos seguindo a guia PRISMA e as recomendações de Cochrane. Foi avaliada a qualidade metodológica com QUADAS e garantiu-se a reprodutibilidade e a integridade. Realizou-se também uma análise de efeitos aleatórios para a sensibilidade, a especificidade, os quocientes de probabilidade, a razão de probabilidade diagnóstica e a Curva Característica de Operação do Receptor (Curva ROC) com seus Intervalos de Confiança (IC) de 95%. Resultados: Foram selecionados 4604 estudos, dos quais somente 3 cumpriram com o protocolo. Foram avaliados 548 infectados com o vírus HTLV I/II e 6.643 saudáveis. O imunodiagnóstico de HTLV I/II apresentou uma sensibilidade de 99% (IC95% = 98,0-99,0), especificidade de 100% (IC95%= 99,9-100), quocientes de probalidade positiva de 315,8 (IC95% = 128,2-778,5) e negativo de 0,02 (IC95% = 0,01-0,04), razão de probabilidade diagnóstica de 24373 (IC95% = 6864-86545) e área sob a curva ROC de 99,9%. Conclusão: São poucos os estudos disponíveis neste campo do imunodiagnóstico HTLV I/II. O elevado número de pessoas analisadas evidenciou alta validade do imunodiagnóstico, o que é decisivo para garantir a inocuidade das unidades de sangue, a detecção de portadores assintomáticos, a diminuição da transmissão e o início do tratamento.

The Link between Cannabis Use, Immune System, and Viral Infections.

Cannabis continues to be the most used drug in the world today. Research shows that cannabis use is associated with a wide range of adverse health consequences that may involve almost every physiological and biochemical system including respiratory/pulmonary complications such as chronic cough and emphysema, impairment of immune function, and increased risk of acquiring or transmitting viral infections such as HIV, HCV, and others. The review of published research shows that cannabis use may impair immune function in many instances and thereby exerts an impact on viral infections including human immune deficiency virus (HIV), hepatitis C infection (HCV), and human T-cell lymphotropic type I and II virus (HTLV-I/II). The need for more research is also highlighted in the areas of long-term effects of cannabis use on pulmonary/respiratory diseases, immune dysfunction and the risk of infection transmission, and the molecular/genetic basis of immune dysfunction in chronic cannabis users.

Modeling and analysis of a within-host HIV/HTLV-I co-infection.

Human immunodeficiency virus (HIV) and human T-lymphotropic virus type I (HTLV-I) are two retroviruses that attack the CD4 + T cells and impair their functions. Both HIV and HTLV-I can be transmitted between individuals through direct contact with certain body fluids from infected individuals. Therefore, a person can be co-infected with both viruses. HIV causes acquired immunodeficiency syndrome (AIDS), while HTLV-I is the causative agent for adult T-cell leukemia (ATL) and HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Several mathematical models have been developed in the literature to describe the within-host dynamics of HIV and HTLV-I mono-infections. However, modeling a within-host dynamics of HIV/HTLV-I co-infection has not been involved. The present paper is concerned with the formulation and investigation of a new HIV/HTLV-I co-infection model under the effect of Cytotoxic T lymphocytes (CTLs) immune response. The model describes the interaction between susceptible CD4 + T cells, silent HIV-infected cells, active HIV-infected cells, silent HTLV-infected cells, Tax-expressing HTLV-infected cells, free HIV particles, HIV-specific CTLs and HTLV-specific CTLs. The HIV can spread by virus-to-cell transmission. On the other side, HTLV-I has two modes of transmission, (i) horizontal transmission via direct cell-to-cell contact through the virological synapse, and (ii) vertical transmission through the mitotic division of Tax-expressing HTLV-infected cells. The well-posedness of the model is established by showing that the solutions of the model are nonnegative and bounded. We define a set of threshold parameters which govern the existence and stability of all equilibria of the model. We explore the global asymptotic stability of all equilibria by utilizing Lyapunov function and Lyapunov-LaSalle asymptotic stability theorem. We have presented numerical simulations to justify the applicability and effectiveness of the theoretical results. In addition, we evaluate the effect of HTLV-I infection on the HIV dynamics and vice versa.

HTLV-I and Strongyloides in Australia: The worm lurking beneath.

Strongyloidiasis and HTLV-I (human T-lymphotropic virus-1) are important infections that are endemic in many countries around the world with an estimated 370 million infected with Strongyloides stercoralis alone, and 5-10 million with HTVL-I. Co-infections with these pathogens are associated with significant morbidity and can be fatal. HTLV-I infects T-cells thus causing dysregulation of the immune system which has been linked to dissemination and hyperinfection of S. stercoralis leading to bacterial sepsis which can result in death. Both of these pathogens are endemic in Australia primarily in remote communities in Queensland, the Northern Territory, and Western Australia. Other cases in Australia have occurred in immigrants and refugees, returned travellers, and Australian Defence Force personnel. HTLV-I infection is lifelong with no known cure. Strongyloidiasis is a long-term chronic disease that can remain latent for decades, as shown by infections diagnosed in prisoners of war from World War II and the Vietnam War testing positive decades after they returned from these conflicts. This review aims to shed light on concomitant infections of HTLV-I with S. stercoralis primarily in Australia but in the global context as well.

Percepção subjetiva de esforço e recuperação da fadiga pós-sessão fisioterapêutica em pacientes com paraparesia espástica tropical / Subjective effort perception and fatigue recovery after physical therapy session in patients with tropical spastic paraparesis

Introdução: Vírus Linfotrópico de Células T Humana do Tipo-1 (HTLV-1) é um retrovírus que afeta os linfócitos T humano e desencadeia inflamação na medula, levando à paraparesia espástica tropical/mielopatia associada ao HTLV-1 (PET/MAH) com prejuízos funcionais. Tais disfunções podem influenciar nos efeitos da fisioterapia, gerando diferentes níveis de fadiga. Objetivo: Avaliar a percepção subjetiva de esforço e de recuperação de indivíduos com PET/MAH após sessão única de fisioterapia. Métodos: Incluíram-se 12 participantes sintomáticos para PET/MAH, de ambos os sexos, que foram submetidos uma vez ao protocolo fisioterapêutico. Os instrumentos avaliativos foram: Escala Modificada de Borg, Escala de Percepção Subjetiva de Recuperação (1º, 5º e 10º minuto após a sessão) e Escala de Incapacidade Neurológica do Instituto de Pesquisa Clínica Evandro Chagas ­ 2 (EIPEC). Resultados: Encontrou-se correlação moderada entre idade e taxa de percepção subjetiva de recuperação ao 1º (r = - 0,4923) e 5º (r = - 0,4913) minuto e entre índice do EIPEC-2 e taxa de percepção subjetiva de recuperação ao 1º (r = 0,3592) e 5º (r = - 0,3772) minuto. Conclusão: Indivíduos deste estudo com maior idade e grau de incapacidade neurológica têm menor percepção subjetiva de recuperação. (AU)

Introduction: Human T-Cell Lymphotropic Virus Type-1 (HTLV-1) is a retrovirus that affects human T lymphocytes and triggers inflammation in the spinal cord, leading to tropical spastic paraparesis / HTLV-1 associated myelopathy (TSP/HAM) with functional impairments. Such dysfunctions can influence the effects of physical therapy, generating different levels of fatigue. Objective: To evaluate the subjective perception of effort and recovery of individuals with TSP/HAM after a single session of physical therapy. Methods: 12 symptomatic participants for TSP/HAM, of both sexes, who were submitted once to a physiotherapeutic protocol were included. The evaluative instruments were: Modified Borg Scale, Scale of Subjective Perception of Recovery (1st, 5th and 10th minute after the session) and Scale of Neurological Disability at the Evandro Chagas Clinical Research Institute - 2 (EIPEC). Results: A moderate correlation was found between age and subjective perception rate of recovery at the 1st (r = - 0.4923) and 5th (r = - 0.4913) minute and between the EIPEC-2 index and the subjective perception rate of recovery at the 1st (r = 0.3592) and 5th (r = - 0.3772) minute. Conclusion: Individuals in this study with older age and degree of neurological disability have less subjective perception of recovery. (AU)