IL-10 predicts incident neuroinflammatory disease and proviral load dynamics in a large Brazilian cohort of people living with human T-lymphotropic virus type 1.

Human T-Lymphotropic Virus type-1 (HTLV-1) is a unique retrovirus associated with both leukemogenesis and a specific neuroinflammatory condition known as HTLV-1-Associated Myelopathy (HAM). Currently, most proposed HAM biomarkers require invasive CSF sampling, which is not suitable for large cohorts or repeated prospective screening. To identify non-invasive biomarkers for incident HAM in a large Brazilian cohort of PLwHTLV-1 (n=615 with 6,673 person-years of clinical follow-up), we selected all plasma samples available at the time of entry in the cohort (between 1997-2019), in which up to 43 cytokines/chemokines and immune mediators were measured. Thus, we selected 110 People Living with HTLV-1 (PLwHTLV-1), of which 68 were neurologically asymptomatic (AS) at baseline and 42 HAM patients. Nine incident HAM cases were identified among 68 AS during follow-up. Using multivariate logistic regression, we found that lower IL-10, IL-4 and female sex were independent predictors of clinical progression to definite HAM (AUROC 0.91), and outperformed previously suggested biomarkers age, sex and proviral load (AUROC 0.77). Moreover, baseline IL-10 significantly predicted proviral load dynamics at follow-up in all PLwHTLV-1. In an exploratory analysis, we identified additional plasma biomarkers which were able to discriminate iHAM from either AS (IL6Rα, IL-27) or HAM (IL-29/IFN-λ1, Osteopontin, and TNFR2). In conclusion, female sex and low anti-inflammatory IL-10 and IL-4 are independent risk factors for incident HAM in PLwHTLV-1,while proviral load is not, in agreement with IL-10 being upstream of proviral load dynamics. Additional candidate biomarkers IL-29/IL-6R/TNFR2 represent plausible therapeutic targets for future clinical trials in HAM patients.

HTLV-1-Associated Myelopathy (HAM) Incidence in Asymptomatic Carriers and Intermediate Syndrome (IS) Patients.

Several studies suggest that HTLV-1 infection may be associated with a wider spectrum of neurological and clinical manifestations that do not meet diagnostic criteria for HAM. These conditions may later progress to HAM or constitute an intermediate clinical form: intermediate syndrome (IS), a mid-point between asymptomatic HTLV-1 carriers and those with full myelopathy. Thus, we determined the incidence of HAM cases in the HTLV-1-asymptomatic and IS patients, and the clinical/laboratory associated markers. A total of 204 HTLV-1-positive patients were included in this study, divided into two groups: Group 1, including 145 asymptomatic HTLV-1 subjects (ASY), and Group 2, including 59 patients with inflammatory clinical symptoms in more than three systems and a high proviral load (PVL). During a 60-month follow-up time, with the age ranging from 47 to 79 years, ten patients of the fifty-nine initially diagnosed as IS developed HAM (iHAM), and two patients of the initial 145 ASY developed HAM directly. Women were more prevalent in all groups. For the iHAM patients, the age ranged from 20 to 72 years, with a mean of 53 (±15 SD). Older age was associated with the development of HAM, higher PVL and IS; however, there was no any specific symptom or clinical sign, that was associated with risk for iHAM. In conclusion, IS cases could be an early phase of development of HAM. These findings show the presence of higher incidence probabilities in our cohort than previously reported.

Could Cesarean Delivery Help Prevent Mother-to-Child Transmission of Human T-Lymphotropic Virus Type 1?

BACKGROUND: Mother-to-child transmission (MTCT) of human T-lymphotropic virus type 1 (HTLV-1) is an important route of transmission that can cause lifelong infection. There is high morbidity and mortality due to adult T-cell leukemia/lymphoma, HTLV-1-associated myelopathy (HAM), and other inflammatory disorders. These conditions develop in nearly 10% of people with HTLV-1 infection, with a higher risk if infection occurs early in life. Identification of risk factors can inform targeted measures to reduce HTLV-1 MTCT. This study aimed to investigate the potential of cesarean delivery to prevent HTLV-1 MTCT. METHODS: We performed a review of the cases of women and their offspring under regular follow-up at the HTLV-1 outpatient clinic at the Institute of Infectious Diseases Emilio Ribas. RESULTS: A total of 177 HTLV-1-infected women and 369 adult offspring were investigated. Overall, 15% of the children were positive for HTLV-1 and 85% were negative. Regarding vertical transmission, we found that a breastfeeding duration of >6 months was associated with MTCT. Moreover, maternal proviral load was not associated with transmission, but high educational level and cesarean delivery were identified as protective factors. CONCLUSIONS: HTLV-1 MTCT was associated with mother's age at delivery of >25 years, low educational level, prolonged breastfeeding, and vaginal delivery.

Systemic cytokines and GlycA discriminate disease status and predict corticosteroid response in HTLV-1-associated neuroinflammation.

BACKGROUND: HTLV-1-Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP) is an incapacitating neuroinflammatory disorder for which no disease-modifying therapy is available, but corticosteroids provide some clinical benefit. Although HAM/TSP pathogenesis is not fully elucidated, older age, female sex and higher proviral load are established risk factors. We investigated systemic cytokines and a novel chronic inflammatory marker, GlycA, as possible biomarkers of immunopathogenesis and therapeutic response in HAM/TSP, and examined their interaction with established risk factors. PATIENTS AND METHODS: We recruited 110 People living with HTLV-1 (PLHTLV-1, 67 asymptomatic individuals and 43 HAM/TSP patients) with a total of 946 person-years of clinical follow-up. Plasma cytokine levels (IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-γ, TNF) and GlycA were quantified by Cytometric Bead Array and 1NMR, respectively. Cytokine signaling and prednisolone response were validated in an independent cohort by nCounter digital transcriptomics. We used multivariable regression, machine learning algorithms and Bayesian network learning for biomarker identification. RESULTS: We found that systemic IL-6 was positively correlated with both age (r = 0.50, p < 0.001) and GlycA (r = 0.45, p = 0.00049) in asymptomatics, revealing an 'inflammaging" signature which was absent in HAM/TSP. GlycA levels were higher in women (p = 0.0069), but cytokine levels did not differ between the sexes. IFN-γ (p = 0.007) and IL-17A (p = 0.0001) levels were increased in untreated HAM/TSP Multivariable logistic regression identified IL-17A and proviral load as independent determinants of clinical status, resulting in modest accuracy of predicting HAM/TSP status (64.1%), while a machine learning-derived decision tree classified HAM/TSP patients with 90.7% accuracy. Pre-treatment GlycA and TNF levels significantly predicted clinical worsening (measured by Osame Motor Disability Scale), independent of proviral load. In addition, a poor prednisolone response was significantly correlated with higher post-treatment IFN-γ levels. Likewise, a transcriptomic IFN signaling score, significantly correlated with previously proposed HAM/TSP biomarkers (CASP5/CXCL10/FCGR1A/STAT1), was efficiently blunted by in vitro prednisolone treatment of PBMC from PLHTLV-1 and incident HAM/TSP. CONCLUSIONS: An age-related increase in systemic IL-6/GlycA levels reveals inflammaging in PLHTLV-1, in the absence of neurological disease. IFN-γ and IL-17A are biomarkers of untreated HAM/TSP, while pre-treatment GlycA and TNF predict therapeutic response to prednisolone pulse therapy, paving the way for a precision medicine approach in HAM/TSP.

Prognosis Markers for Monitoring HTLV-1 Neurologic Disease.

BACKGROUND: Human T-cell lymphotropic virus type 1 (HTLV-1) infection is associated not only with some severe manifestations, such as HTLV-1-associated myelopathy (HAM) and ATLL, but also with other, less severe conditions. Some studies have reported neurologic manifestations that did not meet all the criteria for the diagnosis of HAM in individuals infected with HTLV-1; these conditions may later progress to HAM or constitute an intermediate clinical form, between asymptomatic HTLV-1 carriers and those with full myelopathy. This study evaluated the prognostic value and looked for a possible association of those parameters with the intermediate syndrome (IS) status and HAM status. METHODS: Proviral load (PVL), spontaneous lymphoproliferation, interferon (IFN)-γ spontaneous production was quantified in samples of asymptomatic and HAM patients, as well as patients with IS. RESULTS: The critical age range was 50-60 years for IS outcome and more of 60 years for HAM outcome, with an increased risk of 2.5-fold for IS and 6.8-fold for HAM. IFN-γ was increased in patients with IS compared with asymptomatic carriers (ACs) (p = 0.007) and in patients with HAM compared with ACs (p = 0.03). Lymphoproliferation was increased in patients with HAM vs ACs (p = 0.0001) and patients with IS (p = 0.0001). PVL was similar between groups. CONCLUSION: IFN-γ has high specificity of prediction of subject remain asymptomatic compared with PVL and lymphoproliferation assay tests. IFN-γ has been shown to be a biomarker of progression to intermediate stage and to HAM. The association of other markers with manifestations associated with HTLV-1 infection that does not meet the HAM criteria should be verified.

Small cells lung epidermoid carcinoma in a HTLV1-infected patient: case report and literature review.

The human T cell lymphotropic virus type 1 (HTLV-1) is the first human retrovirus discovered. Since then, it has spread worldwide and is mainly associated with adult T cell leukemia/lymphoma (ATLL) and HTLV1-associated myelopathy (HAM). Its relationship, however, with other types of cancer is controversial. We describe the case of a patient presenting with small cells lung epidermoid carcinoma who had recently developed HAM, and a review of the literature related to these conditions. This is the first case of this type of lung cancer, the same of the first description in the literature, associated with HAM outside Japan.

Dichotomy in fatal outcomes in a large cohort of people living with HTLV-1 in São Paulo, Brazil

BACKGROUND: Despite its relatively low incidence of associated diseases, Human T-cell Leukemia Virus-1 (HTLV-1) infection was reported to carry a significant risk of mortality in several endemic areas. HTLV-1-associated diseases, adult T-cell leukemia/lymphoma (ATLL) and HTLV-1-associated myelopathy/tropical spastic paraperesis (HAM/TSP), as well as frequent coinfections with human immunodeficiency virus (HIV), hepatitis C virus (HCV), and Strongyloides stercoralis were associated to increased morbidity and mortality of HTLV-1 infection. OBJECTIVE: To determine the mortality rate and its associated variables from an open cohort started in July 1997 at the HTLV Clinic, Emilio Ribas Institute (IIER), a major infectious disease hospital in São Paulo, Brazil. METHODS: Since inception up to September 2018, we admitted 727 HTLV-1-infected individuals, with a rate of 30-50 new admissions per year. All patient data, including clinical and laboratory data, were regularly updated throughout the 21-year period, using a dedicated REDCap database. The Ethical Board of IIER approved the protocol. RESULTS: During 21 years of clinical care to people living with HTLV-1 in the São Paulo region, we recruited 479 asymptomatic HTLV-1-infected individuals and 248 HAM/TSP patients, of which 632 remained under active follow-up. During a total of 3800 person-years of follow-up (maximum follow-up 21.5 years, mean follow-up 6.0 years), 27 individuals died (median age of 51.5 years), of which 12 were asymptomatic, one ATLL patient and 14 HAM/TSP patients. HAM/TSP diagnosis (but neither age nor gender) was a significant predictor of increased mortality by univariate and multivariate (hazard ratio (HR) 5.03, 95% CI [1.96-12.91], p = 0.001) Cox regression models. Coinfection with HIV/HCV was an independent predictor of increased mortality (HR 15.08; 95% CI [5.50-41.32]; p < 0.001), with AIDS-related infections as a more frequent cause of death in asymptomatics (6/13; p = 0.033). HIV/HCV-negative fatal HAM/TSP cases were all female, with urinary tract infection and decubitus ulcer-associated sepsis as the main cause of death (8/14, p = 0.002). CONCLUSIONS: All-cause mortality among people living with HTLV-1 in São Paulo differs between asymptomatic (2.9%) and HAM/TSP patients (7.3%), independent of age and gender. We observe a dichotomy in fatal cases, with HAM/TSP and HIV/HCV coinfection as independent risk factors for death. Our findings reveal an urgent need for public health actions, as the major causes of death, infections secondary to decubitus ulcers, and immune deficiency syndrome (AIDS)-related infections, can be targeted by preventive measures

Memory impairment: an intermediate clinical syndrome symptom in HTLV-1-infected patients?

BACKGROUND: Although classical human T-cell lymphocyte virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis syndrome is the most frequent HTLV-1-associated neurological disorder, some "minor" neurological disorders can be seen in "asymptomatic" carriers. These disorders, including cognitive alterations already described in clinical cases and studies, may constitute an intermediate syndrome (IMS) between the asymptomatic state and myelopathy. The aim of this study was to investigate the presence of cognitive deficits in patients with HTLV-1 virus, who usually are diagnosed as asymptomatic. METHODS: A total of 54 HTLV-1-infected patients were evaluated, 35 asymptomatic and 19 with minor neurological alterations (evaluated by a neurologist); 25 HTLV-1-seronegative individuals served as controls. The instruments used were: Beck's Depression Inventory, Lawton's Daily Life Activity Scale, and a complete neuropsychological battery. The application of these evaluation instruments was performed blindly, with the evaluator neuropsychologist not knowing the clinical condition of the patient. RESULTS: Most of the participants in this cohort, including seronegative controls, were female (n = 57, 72.21%), their mean age was 52.34 years (SD = 14.29) and their average schooling was 9.70 years (SD = 4.11). DISCUSSION: Participants classified with IMS had lower gross scores when compared with both the patients classified as asymptomatic and with the control group, and when tested for auditory episodic memory of immediate (p < 0.01), and late (p = 0.01), recall. CONCLUSION: Patients with IMS presented with memory impairment when compared with asymptomatic patients and seronegative individuals; this is one of the symptoms that aids in the classification of the syndrome.

Memory impairment: an intermediate clinical syndrome symptom in HTLV-1-infected patients? / Comprometimento da memória: um sintoma de síndrome clínica intermediária em pacientes infectados pelo HTLV-1?

Background Although classical human T-cell lymphocyte virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis syndrome is the most frequent HTLV-1-associated neurological disorder, some "minor" neurological disorders can be seen in "asymptomatic" carriers. These disorders, including cognitive alterations already described in clinical cases and studies, may constitute an intermediate syndrome (IMS) between the asymptomatic state and myelopathy. The aim of this study was to investigate the presence of cognitive deficits in patients with HTLV-1 virus, who usually are diagnosed as asymptomatic. Methods A total of 54 HTLV-1-infected patients were evaluated, 35 asymptomatic and 19 with minor neurological alterations (evaluated by a neurologist); 25 HTLV-1-seronegative individuals served as controls. The instruments used were: Beck's Depression Inventory, Lawton's Daily Life Activity Scale, and a complete neuropsychological battery. The application of these evaluation instruments was performed blindly, with the evaluator neuropsychologist not knowing the clinical condition of the patient. Results Most of the participants in this cohort, including seronegative controls, were female (n = 57, 72.21%), their mean age was 52.34 years (SD = 14.29) and their average schooling was 9.70 years (SD = 4.11). Discussion Participants classified with IMS had lower gross scores when compared with both the patients classified as asymptomatic and with the control group, and when tested for auditory episodic memory of immediate (p < 0.01), and late (p = 0.01), recall. Conclusion Patients with IMS presented with memory impairment when compared with asymptomatic patients and seronegative individuals; this is one of the symptoms that aids in the classification of the syndrome.

RESUMO Apesar da síndrome de HAM / TSP clássica ser a perturbação neurológica mais atribuída, alguns distúrbios neurológicos denominados "menores" são vistos em portadores "assintomáticos" de HTLV-1. Esses distúrbios, incluindo alterações cognitivas já observadas em descrições de casos clínicos e estudos, podendo constituir uma verdadeira síndrome clínica intermediária (SI) entre o estado assintomático e mielopatia. O objetivo deste estudo foi investigar a presença de déficits cognitivos em pacientes portadores do vírus HTLV-1 diagnosticados classicamente como assintomáticos. Métodos Foram avaliadas 54 pessoas, sendo 35 assintomáticos, 19 com alterações neurológicas menores (avaliados por um neurologista) e 25 HTLV-1 negativo. Os instrumentos utilizados foram: Inventário Beck de Depressão, Escala de Atividades de Vida Diária de Lawton e uma completa bateria neuropsicológica. A aplicação destes instrumentos de avaliação foi realizada de forma cega, ou seja, a avaliadora não sabia a condição clinica do paciente. Resultados A maioria dos participantes era do sexo feminino (n = 57, 72,21%), com idade média de 52.34 anos (DP = 14,29) e escolaridade média de 9.70 anos (DP = 4,11). Discussão Avaliando o desempenho cognitivo nos três grupos, foi possível observar que os participantes classificados com SI, apresentaram menores escores brutos, quando comparados, com os pacientes com classificação assintomática e grupo controle e, em relação à memória episódica auditiva de evocação imediata (p < 0,01) (p = 0,01) e tardia. Conclusão Diante dos resultados foi possível concluir que os pacientes com SI apresentam comprometimento de memória quando comparado com os outros grupos, sendo possível, ser este um dos sintomas para auxiliar na classificação da síndrome.

Detection of clinical and neurological signs in apparently asymptomatic HTLV-1 infected carriers: Association with high proviral load.

Several studies suggest that HTLV-1 infection may be associated with a wider spectrum of neurologic manifestations that do not meet diagnostic criteria for HAM/TSP. These conditions may later progress to HAM/TSP or constitute an intermediate clinical form, between asymptomatic HTLV-1 carriers and those with full myelopathy. Our aim was to determine the prevalence of HTLV-1-associated disease in subjects without HAM/TSP, and the relationship between these findings with HTLV-1 proviral load (PVL). METHODS: 175 HTLV-1-infected subjects were submitted to a careful neurological evaluation, during their regular follow up at the HTLV outpatient clinic of the Institute of Infectious Diseases "Emilio Ribas", São Paulo city, Brazil. Clinical evaluation and blinded standardized neurological screening were performed for all the subjects by the same neurologist (MH). RESULTS: After the neurological evaluation, 133 patients were classified as asymptomatic and 42 fulfilled the criteria for intermediate syndrome (IS). The mean age of the enrolled subjects was 46.3 years and 130 (74.3%) were females. Clinical classification shows that neurological symptoms (p<0.001), visual disorders (p = 0.001), oral conditions (p = 0.001), skin lesions (p<0.001), bladder disorders (p<0.001), and rheumatological symptoms (p = 0.001), were strongly associated to IS, except for disautonomy (p = 0.21). A multivariate analysis revealed that HTLV-1 proviral load, oral conditions, bladder disorders and rheumatological symptoms were independently associated with the IS. CONCLUSIONS: We found some early alterations in 42 patients (24%), particularly the presence of previously not acknowledged clinical and neurological symptoms, among subjects previously classified as "asymptomatic", who we reclassified as having an intermediate syndrome.

Detection of clinical and neurological signs in apparently asymptomatic HTLV-1 infected carriers: Association with high proviral load

Several studies suggest that HTLV-1 infection may be associated with a wider spectrum of neurologic manifestations that do not meet diagnostic criteria for HAM/TSP. These conditions may later progress to HAM/TSP or constitute an intermediate clinical form, between asymptomatic HTLV-1 carriers and those with full myelopathy. Our aim was to determine the prevalence of HTLV-1-associated disease in subjects without HAM/TSP, and the relationship between these findings with HTLV-1 proviral load (PVL). METHODS: 175 HTLV-1-infected subjects were submitted to a careful neurological evaluation, during their regular follow up at the HTLV outpatient clinic of the Institute of Infectious Diseases "Emilio Ribas", São Paulo city, Brazil. Clinical evaluation and blinded standardized neurological screening were performed for all the subjects by the same neurologist (MH). RESULTS: After the neurological evaluation, 133 patients were classified as asymptomatic and 42 fulfilled the criteria for intermediate syndrome (IS). The mean age of the enrolled subjects was 46.3 years and 130 (74.3%) were females. Clinical classification shows that neurological symptoms (p<0.001), visual disorders (p = 0.001), oral conditions (p = 0.001), skin lesions (p<0.001), bladder disorders (p<0.001), and rheumatological symptoms (p = 0.001), were strongly associated to IS, except for disautonomy (p = 0.21). A multivariate analysis revealed that HTLV-1 proviral load, oral conditions, bladder disorders and rheumatological symptoms were independently associated with the IS. CONCLUSIONS: We found some early alterations in 42 patients (24%), particularly the presence of previously not acknowledged clinical and neurological symptoms, among subjects previously classified as "asymptomatic", who we reclassified as having an intermediate syndrome

Dichotomy in Fatal Outcomes in a Large Cohort of People Living with HTLV-1 in São Paulo, Brazil.

Background: Despite its relatively low incidence of associated diseases, Human T-cell Leukemia Virus-1 (HTLV-1) infection was reported to carry a significant risk of mortality in several endemic areas. HTLV-1-associated diseases, adult T-cell leukemia/lymphoma (ATLL) and HTLV-1-associated myelopathy/tropical spastic paraperesis (HAM/TSP), as well as frequent coinfections with human immunodeficiency virus (HIV), hepatitis C virus (HCV), and Strongyloides stercoralis were associated to increased morbidity and mortality of HTLV-1 infection. Objective: To determine the mortality rate and its associated variables from an open cohort started in July 1997 at the HTLV Clinic, Emilio Ribas Institute (IIER), a major infectious disease hospital in São Paulo, Brazil. Methods: Since inception up to September 2018, we admitted 727 HTLV-1-infected individuals, with a rate of 30-50 new admissions per year. All patient data, including clinical and laboratory data, were regularly updated throughout the 21-year period, using a dedicated REDCap database. The Ethical Board of IIER approved the protocol. Results: During 21 years of clinical care to people living with HTLV-1 in the São Paulo region, we recruited 479 asymptomatic HTLV-1-infected individuals and 248 HAM/TSP patients, of which 632 remained under active follow-up. During a total of 3800 person-years of follow-up (maximum follow-up 21.5 years, mean follow-up 6.0 years), 27 individuals died (median age of 51.5 years), of which 12 were asymptomatic, one ATLL patient and 14 HAM/TSP patients. HAM/TSP diagnosis (but neither age nor gender) was a significant predictor of increased mortality by univariate and multivariate (hazard ratio (HR) 5.03, 95% CI [1.96-12.91], p = 0.001) Cox regression models. Coinfection with HIV/HCV was an independent predictor of increased mortality (HR 15.08; 95% CI [5.50-41.32]; p < 0.001), with AIDS-related infections as a more frequent cause of death in asymptomatics (6/13; p = 0.033). HIV/HCV-negative fatal HAM/TSP cases were all female, with urinary tract infection and decubitus ulcer-associated sepsis as the main cause of death (8/14, p = 0.002). Conclusions: All-cause mortality among people living with HTLV-1 in São Paulo differs between asymptomatic (2.9%) and HAM/TSP patients (7.3%), independent of age and gender. We observe a dichotomy in fatal cases, with HAM/TSP and HIV/HCV coinfection as independent risk factors for death. Our findings reveal an urgent need for public health actions, as the major causes of death, infections secondary to decubitus ulcers, and immune deficiency syndrome (AIDS)-related infections, can be targeted by preventive measures.

Risk factors associated with HTLV-1 vertical transmission in Brazil: longer breastfeeding, higher maternal proviral load and previous HTLV-1-infected offspring.

HTLV-1 is transmitted primarily either through sexual intercourse or from mother to child. The mother/child pairs were classified as seroconcordant or serodiscordant. We analyzed mother to child transmission (MTCT) according to sociodemographic, clinical and epidemiological characteristics of the mother, child's gender and duration of breastfeeding. Between June 2006 and August 2016 we followed 192 mothers with HTLV-1 infection (mean age 41 years old), resulting in 499 exposed offspring, 288 (57.7%) of whom were tested for HTLV-1, making up the final sample for the study, along with their 134 respective mothers. Among the tested mother/child pairs, 41 (14.2%) were HTLV-1 positive, highlighted that seven of 134 family clusters concentrated 48.8% of positive cases. Variables associated with a positive child: breastfeeding duration ≥12 months, maternal PVL ≥100 copies/104 PBMC, mother's age at delivery >26 years old, and HTLV-1 in more than one child of the same mother. In a multiple logistic regression, breastfeeding ≥12 months, higher maternal PVL and ≥2 previous HTLV-1-infected children remained independently associated with the outcome. Thus, high maternal PVL and breastfeeding beyond 12 months were independently associated with MTCT of the HTLV-1 infection. Our results reinforce the need for both prenatal HTLV screening in endemic areas and for advising mothers on breastfeeding.

Risk factors associated with HTLV-1 vertical transmission in Brazil: longer breastfeeding, higher maternal proviral load and previous HTLV-1-infected offspring

HTLV-1 is transmitted primarily either through sexual intercourse or from mother to child. The mother/child pairs were classified as seroconcordant or serodiscordant. We analyzed mother to child transmission (MTCT) according to sociodemographic, clinical and epidemiological characteristics of the mother, child's gender and duration of breastfeeding. Between June 2006 and August 2016 we followed 192 mothers with HTLV-1 infection (mean age 41 years old), resulting in 499 exposed offspring, 288 (57.7%) of whom were tested for HTLV-1, making up the final sample for the study, along with their 134 respective mothers. Among the tested mother/child pairs, 41 (14.2%) were HTLV-1 positive, highlighted that seven of 134 family clusters concentrated 48.8% of positive cases. Variables associated with a positive child: breastfeeding duration ≥12 months, maternal PVL ≥100 copies/104 PBMC, mother's age at delivery >26 years old, and HTLV-1 in more than one child of the same mother. In a multiple logistic regression, breastfeeding ≥12 months, higher maternal PVL and ≥2 previous HTLV-1-infected children remained independently associated with the outcome. Thus, high maternal PVL and breastfeeding beyond 12 months were independently associated with MTCT of the HTLV-1 infection. Our results reinforce the need for both prenatal HTLV screening in endemic areas and for advising mothers on breastfeeding

In vitro basal T-cell proliferation among asymptomatic Human T cell Leukemia Virus type 1 patients co-infected with hepatitis C and/or Human Immunodeficiency Virus type 1.

BACKGROUND: Infection with Human T cell Leukemia Virus type 1 can be associated with myelopathy/tropical spastic paraparesis (HAM/TSP) and other inflammatory diseases. Lymphocytes from about half of Human T cell Leukemia Virus type 1-infected subjects spontaneously proliferate in vitro, and how this phenomenon relates to symptomatic disease and viral burden is poorly understood. OBJECTIVE: To evaluate T-cell proliferation in vitro among patients co-infected with Human T cell Leukemia Virus type 1/Hepatitis C Virus/Human Immunodeficiency Virus type 1. MATERIAL AND METHODS: From 610 Human T cell Leukemia Virus-infected patients of the Human T cell Leukemia Virus outpatient clinic from Institute of Infectious Diseases "Emilio Ribas" in São Paulo, 273 agreed to participate: 72 had HAM/TSP (excluded from this analysis) and 201 were asymptomatic, a classification performed during a regular neurological appointment. We selected the subgroup made up only by the 201 asymptomatic subjects to avoid bias by the clinical status as a confounder effect, who had laboratory results of Human T cell Leukemia Virus type 1 proviral load and T-cell proliferation assay in our database. They were further grouped according to their serological status in four categories: 121 Human T cell Leukemia Virus type 1 asymptomatic mono-infected carriers; 32 Human T cell Leukemia Virus type 1/Hepatitis C Virus, 29 Human T cell Leukemia Virus type 1/Human Immunodeficiency Virus type 1, and 19 Human T cell Leukemia Virus type 1/Human Immunodeficiency Virus type 1/Hepatitis C Virus co-infected patients. Clinical data were obtained from medical records and interviews. DNA Human T cell Leukemia Virus type 1 proviral load (PVL) and T-cell proliferation (LPA) assay were performed for all samples. RESULTS: From a total of 273 subjects with Human T cell Leukemia Virus type 1, 80 presented co-infections: 29 had Human Immunodeficiency Virus type 1, 32 had Hepatitis C Virus, and 19 had Human Immunodeficiency Virus type 1 and Hepatitis C Virus. Comparing the groups based on their serological status, independently of being asymptomatic carriers, we observed a significant increase of PVL (p<0.001) and LPA (p=0.001). However, when groups were stratified according to their clinical and serological status, there was no significant increase in Human T cell Leukemia Virus type 1 PVL and LPA. CONCLUSION: No significant increase of basal T-cell proliferation among Human T cell Leukemia Virus type 1 co-infected was observed. This interaction may be implicated in liver damage, worsening the prognosis of co-infected patients or, on the contrary, inducing a higher spontaneous clearance of Hepatitis C Virus infection in Human T cell Leukemia Virus type 1 co-infected patients.

In vitro basal T-cell proliferation among asymptomatic Human T cell Leukemia Virus type 1 patients co-infected with hepatitis C and/or Human Immunodeficiency Virus type 1

ABSTRACT Background: Infection with Human T cell Leukemia Virus type 1 can be associated with myelopathy/tropical spastic paraparesis (HAM/TSP) and other inflammatory diseases. Lymphocytes from about half of Human T cell Leukemia Virus type 1-infected subjects spontaneously proliferate in vitro, and how this phenomenon relates to symptomatic disease and viral burden is poorly understood. Objective: To evaluate T-cell proliferation in vitro among patients co-infected with Human T cell Leukemia Virus type 1/Hepatitis C Virus/Human Immunodeficiency Virus type 1. Material and methods: From 610 Human T cell Leukemia Virus-infected patients of the Human T cell Leukemia Virus outpatient clinic from Institute of Infectious Diseases "Emilio Ribas" in São Paulo, 273 agreed to participate: 72 had HAM/TSP (excluded from this analysis) and 201 were asymptomatic, a classification performed during a regular neurological appointment. We selected the subgroup made up only by the 201 asymptomatic subjects to avoid bias by the clinical status as a confounder effect, who had laboratory results of Human T cell Leukemia Virus type 1 proviral load and T-cell proliferation assay in our database. They were further grouped according to their serological status in four categories: 121 Human T cell Leukemia Virus type 1 asymptomatic mono-infected carriers; 32 Human T cell Leukemia Virus type 1/Hepatitis C Virus, 29 Human T cell Leukemia Virus type 1/Human Immunodeficiency Virus type 1, and 19 Human T cell Leukemia Virus type 1/Human Immunodeficiency Virus type 1/Hepatitis C Virus co-infected patients. Clinical data were obtained from medical records and interviews. DNA Human T cell Leukemia Virus type 1 proviral load (PVL) and T-cell proliferation (LPA) assay were performed for all samples. Results: From a total of 273 subjects with Human T cell Leukemia Virus type 1, 80 presented co-infections: 29 had Human Immunodeficiency Virus type 1, 32 had Hepatitis C Virus, and 19 had Human Immunodeficiency Virus type 1 and Hepatitis C Virus. Comparing the groups based on their serological status, independently of being asymptomatic carriers, we observed a significant increase of PVL (p < 0.001) and LPA (p = 0.001). However, when groups were stratified according to their clinical and serological status, there was no significant increase in Human T cell Leukemia Virus type 1 PVL and LPA. Conclusion: No significant increase of basal T-cell proliferation among Human T cell Leukemia Virus type 1 co-infected was observed. This interaction may be implicated in liver damage, worsening the prognosis of co-infected patients or, on the contrary, inducing a higher spontaneous clearance of Hepatitis C Virus infection in Human T cell Leukemia Virus type 1 co-infected patients.

High risk of heterosexual transmission of human T-cell lymphotropic virus type 1 infection in Brazil

Human T-cell lymphotropic virus type 1 is transmitted primarily either through sexual intercourse or from mother to child. The current study investigated sexual transmission and compared the HTLV-1 proviral load between seroconcordant and serodiscordant couples by examining both men and women among the index partners without using subjective criteria to establish the direction of sexual transmission. Between January 2013 and May 2015, 178 HTLV-1-positive patients had spouses, 107 of which had tested partners, thus increasing the initial sample size (46 men and 61 women). Individuals co-infected with HTLV-2 or human immunodeficiency virus were not included in the analysis. From among the included participants, 26 men and 26 women were paired with each other, resulting in 26 seroconcordant couples; 12 seroconcordant couples were formed from another four men and eight women. Forty-three serodiscordant couples were formed from 16 men and 27 women. The rate of seroconcordance was 46.9%. The HTLV-1 proviral load was compared between 19 and 37 seroconcordant and serodiscondant couples, respectively, and the concordant couples showed higher proviral loads (P = 0.03). There were no differences between the groups according to age, relationship length, having a mother or sibling with HTLV-1, race, ethnicity, nationality, education, history of blood transfusion, HAM/TSP, ALT, or hepatitis C virus status. In multivariate analysis, relationship time was shown associated with ocurrence of seroconcordance status. The apparent association between high circulating levels of provirus and seroconcordance rate among couples suggests that proviral loads contribute markedly to the risk of sexual transmission, regardless of gender index

High risk of heterosexual transmission of human T-cell lymphotropic virus type 1 infection in Brazil.

Human T-cell lymphotropic virus type 1 is transmitted primarily either through sexual intercourse or from mother to child. The current study investigated sexual transmission and compared the HTLV-1 proviral load between seroconcordant and serodiscordant couples by examining both men and women among the index partners without using subjective criteria to establish the direction of sexual transmission. Between January 2013 and May 2015, 178 HTLV-1-positive patients had spouses, 107 of which had tested partners, thus increasing the initial sample size (46 men and 61 women). Individuals co-infected with HTLV-2 or human immunodeficiency virus were not included in the analysis. From among the included participants, 26 men and 26 women were paired with each other, resulting in 26 seroconcordant couples; 12 seroconcordant couples were formed from another four men and eight women. Forty-three serodiscordant couples were formed from 16 men and 27 women. The rate of seroconcordance was 46.9%. The HTLV-1 proviral load was compared between 19 and 37 seroconcordant and serodiscondant couples, respectively, and the concordant couples showed higher proviral loads (P = 0.03). There were no differences between the groups according to age, relationship length, having a mother or sibling with HTLV-1, race, ethnicity, nationality, education, history of blood transfusion, HAM/TSP, ALT, or hepatitis C virus status. In multivariate analysis, relationship time was shown associated with ocurrence of seroconcordance status. The apparent association between high circulating levels of provirus and seroconcordance rate among couples suggests that proviral loads contribute markedly to the risk of sexual transmission, regardless of gender index.