Novel insights into human T-lymphotropic virus type-1 (HTLV-1) pathogenesis-host interactions in the manifestation of HTLV-1-associated myelopathy/tropical spastic paraparesis.

Human T-lymphotropic virus type-1 (HTLV-1) was the first discovered human oncogenic retrovirus, the etiological agent of two serious diseases have been identified as adult T-cell leukaemia/lymphoma malignancy and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a debilitating chronic neuro-myelopathy. Despite more than 40 years of molecular, histopathological and immunological studies on HTLV-1-associated diseases, the virulence and pathogenicity of this virus are yet to be clarified. The reason why the majority of HTLV-1-infected individuals (∼95%) remain asymptomatic carriers is still unclear. The deterioration of the immune system towards oncogenicity and autoimmunity makes HTLV-1 a natural probe for the study of malignancy and neuro-inflammatory diseases. Additionally, its slow worldwide spreading has prompted public health authorities and researchers, as urged by the WHO, to focus on eradicating HTLV-1. In contrast, neither an effective therapy nor a protective vaccine has been introduced. This comprehensive review focused on the most relevant studies of the neuro-inflammatory propensity of HTLV-1-induced HAM/TSP. Such an emphasis on the virus-host interactions in the HAM/TSP pathogenesis will be critically discussed epigenetically. The findings may shed light on future research venues in designing and developing proper HTLV-1 therapeutics.

Infective dermatitis associated with human T-cell lymphotropic virus type-1, an underdiagnosed disease.

Infective dermatitis associated with human T-cell lymphotropic virus type-1 (HTLV-1) (IDH) is a severe form of chronically infected eczema occurring in early childhood, although very rarely cases have been reported in adults. Most of the cases are from Jamaica and Brazil and occur in individuals with low socioeconomic status. IDH is always associated with refractory Staphylococcus aureus or beta-hemolytic Streptococcus infection of the skin and nasal vestibules. Patients with IDH may develop other even more severe HTLV-1-associated diseases, such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) of early or late appearance and adult T-cell leukemia/lymphoma. In the context of the Brazilian experience, it has been observed that 54% of IDH patients exhibit the juvenile form of HAM/TSP while the estimated incidence of adult HAM/TSP is 3%. As there are no curative treatments for HTLV-1 infection (or vaccines) or most of its associated diseases, prevention of infection is fundamental, mainly by vertical transmission, as it is responsible for the development of IDH, infantojuvenile HAM/TSP, and ATL. Public measures to reduce this transmission must be implemented urgently. Furthermore, it is recommended, mainly in HTLV-1 endemic areas, to search for HTLV-1 infection in all patients with infected eczema, even in adults.

Cannabinoid receptors as new targets for HTLV-1 associated myelopathy (HAM/TSP) treatment.

BACKGROUND/AIM: The roles of endocannabinoids are described in immune modulation and neuroprotection. HTLV-1-associated myelopathy (HAM/TSP) is an inflammatory neurodegenerative disease. Therefore, in this study, the interactions of HTLV-1 regulatory factors and host cannabinoid receptors (CBRs) were evaluated in HAM/TSP. METHODS: Nineteen HAM/TSPs, 22 asymptomatic carriers (ACs), and 18 healthy controls (HCs) were enrolled. RNA was extracted from PBMCs and then reverse-transcribed to cDNA. The gene expression of CB1R and CB2R, as well as HTLV-1 proviral load (PVL), Tax and HTLV-1 basic leucine zipper factor (HBZ) were assessed by RT-qPCR. RESULTS: The mean expression of CB1R in ACs (8.51 ± 2.76) was significantly higher than HAMTSPs (1.593 ± 0.74, p = 0.05) and also HCs (0.10 ± 0.039, p = 0.001). The CB2R gene expression level in ACs (2.62±0.44) was significantly higher than HAM/TSPs (0.59 ± 0.15, p = 0.001) and HCs (1.00 ± 0.2, p = 0.006). Meanwhile there was a strong correlation between CB1R and CB2R gene expression levels in the HCs and HAM/TSPs (p = 0.001). HTLV-1-Tax expression in HAM/TSPs (386 ± 104) was higher than ACs (75 ± 32) and statistically significant (p = 0.003). While HTLV-1-HBZ was only expressed in three AC subjects and five HAM/TSPs, thus it cannot be analyzed. CONCLUSION: The up-regulation of CB2R has immunomodulatory effects in inflammatory reactions. While CB1R as a neuroprotective agent may suppress inflammatory reactions in ACs, preventing HAM/TSP. It seems that, like multiple sclerosis (MS), cannabinoid medications are beneficial in HAM/TSP.

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.

Complete Rescue of HTLV-1p12KO Infectivity by Depletion of Monocytes Together with NK and CD8+ T Cells.

The transient depletion of monocytes alone prior to exposure of macaques to HTLV-1 enhances both HTLV-1WT (wild type) and HTLV-1p12KO (Orf-1 knockout) infectivity, but seroconversion to either virus is not sustained over time, suggesting a progressive decrease in virus expression. These results raise the hypotheses that either HTLV-1 persistence depends on a monocyte reservoir or monocyte depletion provides a transient immune evasion benefit. To test these hypotheses, we simultaneously depleted NK cells, CD8+ T cells, and monocytes (triple depletion) prior to exposure to HTLV-1WT or HTLV-1p12KO. Remarkably, triple depletion resulted in exacerbation of infection by both viruses and complete rescue of HTLV-1p12KO infectivity. Following triple depletion, we observed rapid and sustained seroconversion, high titers of antibodies against HTLV-1 p24Gag, and frequent detection of viral DNA in the blood and tissues of all animals when compared with depletion of only CD8+ and NK cells, or monocytes alone. The infection of macaques with HTLV-1WT or HTLV-1p12KO was associated with higher plasma levels of IL-10 after 21 weeks, while IL-6, IFN-γ, IL-18, and IL-1ß were only elevated in animals infected with HTLV-1WT. The repeat depletion of monocytes, NK, and CD8+ cells seven months following the first exposure to HTLV-1 did not further exacerbate viral replication. These results underscore the contribution of monocytes in orchestrating anti-viral immunity. Indeed, the absence of orf-1 expression was fully compensated by the simultaneous depletion of CD8+ T cells, NK cells, and monocytes, underlining the primary role of orf-1 in hijacking host immunity.

HTLV in Sweden.

Sweden is a country with a low prevalence of human lymphotropic T-cell virus (HTLV) infection, estimated at < 0.005%, but the infection rate is notably higher in specific risk groups such as HTLV-2 among intravenous drug users (IVDU) and people originating from HTLV-1 highly endemic areas. Thus, in the most recent study from 2012, the prevalence of HTLV-2 among IVDU in Stockholm was 3.2%. However, much of the epidemiological data on HTLV in Sweden stems from studies conducted primarily between the 1990s and 2007, and the impact of migration to Sweden during the past 15 years has not been evaluated. Despite Sweden's status as a country with generally low prevalence of HTLV, it is prudent to anticipate and prepare for several potential challenges associated with HTLV infection in the future. Proactive measures to enhance awareness, alongside strategies to curtail transmission and mitigate complications, are crucial for addressing this relatively rare, but significant health issue. In this work, we review the current epidemiological knowledge about HTLV in Sweden and discuss future Swedish perspectives.

Multicenter, randomized, double-blind, placebo-controlled phase 3 study of mogamulizumab with open-label extension study in a minimum number of patients with human T-cell leukemia virus type-1-associated myelopathy.

Human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic neurodegenerative disease. This multicenter, randomized phase 3 study evaluated the efficacy and safety of 0.3 mg/kg intravenous mogamulizumab, a monoclonal antibody targeting-CC chemokine receptor 4, every 12 weeks in HAM/TSP patients. This study comprised a 24-week double-blind, placebo-controlled period, 24-week open-label period, and extension treatment period. The primary endpoint was the proportion of patients with a ≥ 1-grade improvement in the Osame motor disability score (OMDS). Secondary endpoints were changes in HTLV-1 proviral load, 10-m timed walk, cerebrospinal fluid (CSF) neopterin levels, and safety. The exploratory endpoint was CSF chemokine C-X-C motif ligand 10 (CXCL10) levels. Thirty-four and 33 patients were randomized to mogamulizumab and placebo arms, respectively. At the end of the double-blind period, no significant difference was found in the OMDS improvement rate or other secondary efficacy endpoints assessing motor activities. However, the mogamulizumab arm showed a significant decrease in HTLV-1 proviral load (- 59.39 ± 29.91% vs. placebo 2.32 ± 36.31%) and CSF neopterin (p < 0.001)/CXCL10 levels (p = 0.004). The baseline OMDS pattern and the 60-80% HTLV-1 proviral load reduction were sustained through the open-label and extension treatment periods. Although a higher incidence of rash (69.2%) was reported, the safety profile was similar compared with a previous phase 1/2a study. We found no significant difference in clinical benefit; however, mogamulizumab may provide long-term clinical benefit by preventing disease progression, as CSF neopterin/CXCL10 levels are associated with long-term prognosis in HAM/TSP.Clinical Trial Registration Number: NCT03191526 (registered date: 6-June-2017).

Mycophenolate mofetil for the long-term treatment of HTLV-1 associated myelopathy: A case report.

Human T-cell leukemia virus type 1 (HTLV-1) can cause HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP). Current treatment options for HAM/TSP are limited. We present a woman with rapidly-progressive HAM/TSP with significant, sustained clinical improvement following initiation of mycophenolate mofetil (MMA). Peripheral blood mononuclear cells from the patient, her asymptomatic carrier husband and eight healthy controls were isolated. Frequencies of T-cell populations upon exposure to low and high MMA concentrations and differences in proliferation were analyzed using flow cytometry and a CSFE-proliferation assay. Characterization of T-cell function and proliferation showed higher levels of GranzymeB in HTLV-1+ donors. The improvement and stability of symptoms in this patient with HAM/TSP following MMA initiation requires further study as a potential treatment for HAM/TSP.

Advances in the treatment of human T-cell lymphotropic virus type-I associated myelopathy.

INTRODUCTION: Nearly 2-3% of those 10 to 20 million individuals infected with the Human T-cell lymphotropic virus type-1 (HTLV-1); are predisposed to developing HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It is a neuro-inflammatory disease; differentiated from multiple sclerosis based on the presence of typical neurologic symptoms, confirmation of HTLV-1 infection, and other molecular biomarkers. AREAS COVERED: A brief review of the epidemiology, host immune responses, and molecular pathogenesis of HAM/TSP is followed by detailed discussions about the host-related risk factors for developing HAM/TSP and success/failure stories of the attempted management strategies. EXPERT OPINION: Currently, there is no effective treatment for HAM/TSP. Anti-retroviral therapy, peculiar cytokines (IFN-α), some anti-oxidants, and allograft bone marrow transplantation have been used for treating these patients with limited success. Under current conditions, asymptomatic carriers should be examined periodically by a neurologist for early signs of spinal cord injury. Then it is crucial to determine the progress rate to adapt the best management plan for each patient. Corticosteroid therapy is most beneficial in those with acute myelitis. However, slow-progressing patients are best managed using a combination of symptomatic and physical therapy. Additionally, preventive measures should be taken to decrease further spread of HTLV-1 infection.

Tropical spastic paraparesis.

A large number of causative agents can result in spinal cord disorders in the tropics including etiologies similar to those of temperate regions such as trauma, spinal bone and disc lesions, tumors, epidural abscess, and congenital malformations. Yet infectious and nutritional disorders differ in their higher prevalence in tropical regions including Pott's disease; brucellosis; neuroborreliosis; various parasitic diseases such as schistosomiasis, neurocysticercosis, and eosinophilic meningitis. Notably, the retrovirus HTLV-1 is the causeof tropical spastic paraparesis/paraplegia or TSP. Nutritional causes of TSP include vitamin B and folate deficiencies, while endemic clusters of konzo and tropical ataxic myeloneuropathy occur in Africa, along with malnutrition and excessive consumption of cyanide-containing bitter cassava. Other toxic etiologies of TSP include lathyrism and fluorosis. Nutritional forms of myelopathy are associated often with optic and sensory neuropathy, hence the name tropical myeloneuropathies. Acute transverse myelopathy, seen in association with vaccination, infections, and fibrocartilaginous embolism of the nucleus pulposus, can be ubiquitous. Multiple sclerosis and optic myelopathy occur in the tropics but with lesser prevalence than in temperate regions. The advent of modern imaging in the tropics, including computed tomography and magnetic resonance imaging, has allowed better diagnosis and treatment of these conditions that are a frequent cause of death and disability. This chapter provides an overview of TSP emphasizing the most common causes with clues to diagnosis and effective therapy.

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.

The mirror like expression of genes involved in the FOXO signaling pathway could be effective in the pathogenesis of human lymphotropic virus type 1 (HTLV-1) through disruption of the downstream pathways.

OBJECTIVES: Human lymphotropic virus type 1 (HTLV-1) is the cause of two major diseases, ATLL and HAM/TSP in a percentage of carriers. Despite progress in understanding the pathogenesis of these two diseases, the exact pathogenesis mechanism is still not well understood. High-throughput technologies have revolutionized medical research. This study aims to investigate the mechanism of pathogenesis of these two diseases using the results of high-throughput analysis of microarray datasets. RESULTS: A total of 100 differentially expressed genes were found between ATLL and HAM/TSP. After constructing protein-protein network and further analyzing, proteins including ATM, CD8, CXCR4, PIK3R1 and CD2 were found as the hub ones between ATLL and HAM/TSP. Finding the modules of the subnetwork revealed the enrichment of two common pathways including FOXO signaling pathway and Cell cycle with two common genes including ATM and CDKN2D. Unlike ATLL, ATM gene had higher expressions in HAM/TSP patients. The expression of CDKN2D was increased in ATLL patients. The results of this study could be helpful for understanding the pathogenic mechanism of these two diseases in the same signaling pathways.

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.

Distribución geográfica y tipo de infección del virus linfotrópico T humano en pacientes peruanos 2019-2021 / Geographic distribution and type of human T-lymphotropic virus (HTLV) infection in Peruvian patients 2019-2021

En el presente estudio describimos y caracterizamos la distribución geográfica de los casos positivos confirmados a HTLV-1 y 2 de pacientes peruanos con diagnóstico presuntivo entre 2019 y 2021. De un total de 555 muestras positivas confirmadas, 546 (98,4%) fueron HTLV-1 y 9 (1,6%) HTLV-2. Además, 22 de 24 departamentos del Perú presentaron casos de HTLV-1, siendo los principales motivos de solicitud de confirmación diagnóstica: aspirante a donar sangre con prueba de tamizaje reactivo, sospecha de leucemia/linfoma y paraparesia espástica tropical. Los resultados reflejan que la identificación de los puntos críticos constituye una brecha persistente respecto al diagnóstico, siendo cruciales para reducir el número de nuevos casos en Perú.

In the present study we describe and characterize the geographic distribution of HTLV-1 and 2 positive cases from Peruvian patients with presumptive diagnosis 2019 - 2021. Of a total of 555 confirmed positive samples, 546 (98.4%) were HTLV-1 and 9 (1.6%) HTLV-2. In addition, 22 of 24 departments of Peru presented cases of HTLV-1. The main reasons for requesting a confirmatory diagnosis being: aspiring to donate blood with a reactive screening test, suspicion of leukemia/ lymphoma and tropical spastic paraparesis. The results reflect that the identification of critical points constitutes a persistent gap regarding the diagnosis, being crucial to reduce the number of new cases in Peru.

Precise excision of HTLV-1 provirus with a designer-recombinase.

The human T cell leukemia virus type 1 (HTLV-1) is a pathogenic retrovirus that persists as a provirus in the genome of infected cells and can lead to adult T cell leukemia (ATL). Worldwide, more than 10 million people are infected and approximately 5% of these individuals will develop ATL, a highly aggressive cancer that is currently incurable. In the last years, genome editing tools have emerged as promising antiviral agents. In this proof-of-concept study, we use substrate-linked directed evolution (SLiDE) to engineer Cre-derived site-specific recombinases to excise the HTLV-1 proviral genome from infected cells. We identified a conserved loxP-like sequence (loxHTLV) present in the long terminal repeats of the majority of virus isolates. After 181 cycles of SLiDE, we isolated a designer-recombinase (designated RecHTLV), which efficiently recombines the loxHTLV sequence in bacteria and human cells with high specificity. Expression of RecHTLV in human Jurkat T cells resulted in antiviral activity when challenged with an HTLV-1 infection. Moreover, expression of RecHTLV in chronically infected SP cells led to the excision of HTLV-1 proviral DNA. Our data suggest that recombinase-mediated excision of the HTLV-1 provirus represents a promising approach to reduce proviral load in HTLV-1-infected individuals, potentially preventing the development of HTLV-1-associated diseases.

Th17/IL-17 Axis in HTLV-1-Associated Myelopathy Tropical Spastic Paraparesis and Multiple Sclerosis: Novel Insights into the Immunity During HAMTSP.

Human T lymphotropic virus-associated myelopathy/tropical spastic paraparesis (HTLV/TSP), also known as HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP), and multiple sclerosis (MS) are chronic debilitating diseases of the central nervous system; although the etiology of which is different, similarities have been observed between these two demyelinating diseases, especially in clinical manifestation and immunopathogenesis. Exorbitant response of the immune system to the virus and neurons in CNS is the causative agent of HAM/TSP and MS, respectively. Helper T lymphocyte-17 cells (Th17s), a component of the immune system, which have a proven role in immunity and autoimmunity, mediate protection against bacterial/fungal infections. The role of these cells has been reviewed in several CNS diseases. A pivotal role for Th17s is presented in demyelination, even more axial than Th1s, during MS. The effect of Th17s is not well determined in HTLV-1-associated infections; however, the evidence that we have supplied in this review illustrates the attendance, also the role of Th17 cells during HAM/TSP. Furthermore, for better conception concerning the trace of these cells in HAM/TSP, a comparative characterization with MS, the resembling disease, has been applied here.

HTLV-1-associated demyelinating neuropathy: A case report and review of the literature.

A 78-year-old man developed paresthesias in the extremities. He was referred to our hospital because of positive anti-human T-cell leukemia virus type 1 (HTLV-1) antibodies in the serum and the presence of abnormal lymphocytes. He was diagnosed as chronic-type adult T-cell leukemia/lymphoma. Neurological examination revealed sensory impairment in the distal parts of the extremities with loss of deep tendon reflexes. Nerve conduction study showed motor and sensory demyelinating polyneuropathy, indicating a diagnosis of HTLV-1-associated demyelinating neuropathy. Corticosteroid therapy followed by intravenous immunoglobulin therapy improved his symptoms. Since demyelinating neuropathy associated with HTLV-1 infection is not well recognized, we here report its characteristics and clinical course through our case report and literature review.

Elderly people with human T-cell leukemia virus type 1-associated myelopathy present an early impairment in cognitive skills / Idosos com mielopatia associada ao vírus da leucemia de células T humanas tipo 1apresentam comprometimento precoce em habilidades cognitivas

Abstract Background Cerebral changes occur in individuals with human T-cell leukemia virus type 1 (HTLV-1 )-associated myelopathy (HAM) and seem to predominate in subcortical areas. Little is known about the cognitive decline in the elderly living with HTLV-1. Objective To evaluate the cognitive aging of individuals infected with HTLV-1 aged ≥ 50 years. Methods This is a cross-sectional study of former blood donors infected with HTLV-1 who have been followed in the cohort of the Interdisciplinary Research Group on HTLV-1 since 1997. The groups of study consisted of 79 HTLV-1 infected individuals aged ≥ 50 years, with 41 of them presenting symptomatic HAM and 38 being asymptomatic carriers, and 59 seronegative individuals (controls) aged ≥ 60 years. All were submitted to the P300 electrophysiological test and neuropsychological tests. Results Individuals with HAM presented delayed P300 latency in relation to the other groups, and this latency delay increased progressively with aging. The performance of this group in the neuropsychological tests was also the worst. The HTLV-1- asymptomatic group performance was similar to that of the control group. Conclusions Individuals with HAM presented cognitive decline that progressed with aging and, although HTLV-1-asymptomatic carriers appear to present cognitive aging similar to that of healthy elderly people, concern about a subclinical cognitive impairment is warranted in this population.

Resumo Antecedentes Alterações cerebrais ocorrem em indivíduos com mielopatia associada ao vírus da leucemia de células T humanas tipo 1 (HTLV-1) (HAM) e parecem predominar em áreas subcorticais. Pouco se sabe sobre o declínio cognitivo em idosos vivendo com HTLV-1. Objetivo Avaliar o envelhecimento cognitivo de indivíduos infectados pelo HTLV-1 com idade ≥ 50 anos. Métodos Trata-se de um estudo transversal com ex-doadores de sangue infectados pelo HTLV-1 acompanhados na coorte do Grupo Interdisciplinar de Pesquisa em HTLV-1 há 20 anos. Os grupos de estudo foram compostos por 79 indivíduos infectados pelo HTLV-1 com idade ≥ 50 anos, sendo que 41 apresentavam HAM e 38 eram portadores assintomáticos, e 59 indivíduos soronegativos (controles) com idade ≥ 60 anos. Todos foram submetidos ao teste eletrofisiológico P300 e testes neuropsicológicos. Resultados Indivíduos com HAM apresentaram atraso na latência do P300 em relação aos demais grupos, e esse atraso de latência aumentou progressivamente com o envelhecimento. O desempenho desse grupo nos testes neuropsicológicos também foi o pior. O desempenho do grupo HTLV-1- assintomático foi semelhante ao do grupo controle. Conclusão Indivíduos com HAM apresentaram declínio cognitivo que progrediu com o envelhecimento e, embora os portadores assintomáticos do HTLV-1 pareçam apresentar envelhecimento cognitivo semelhante ao dos idosos saudáveis, justificase a preocupação com um comprometimento cognitivo subclínico nessa população.

Impaired flexibility in patients with tropical spastic paraparesis/HTLV-associated myelopathy: evaluation via pendulum fleximeter / Flexibilidade prejudicada em pacientes com paraparesia espástica tropical/mielopatia associada ao HTLV: avaliação via flexímetro pendular

Abstract Background Flexibility is crucial to the harmonious execution of joint movements. While skeletal muscle dysfunction in patients with HTLV-1 can interfere with mobility, it is unclear whether these patients experience reduced flexibility. Objective To evaluate the differences in flexibility between HTLV-1-infected individuals with and without myelopathy compared with uninfected controls. We also investigated whether age, sex, body mass index (BMI), physical activity level, or lower back pain influence flexibility in HTLV-1-infected individuals. Methods The sample consisted of 56 adults, of which 15 did not have HTLV-1, 15 had HTLV-1 without myelopathy, and 26 had TSP/HAM. Their flexibility was assessed using the sit-and-reach test and a pendulum fleximeter. Results No differences in flexibility were observed between the groups with and without myelopathy and controls without HTLV-1 infection using the sit-and-reach test. The pendulum fleximeter results of individuals with TSP/HAM presented the lowest flexibility among the groups with respect to trunk flexion, hip flexion and extension, knee flexion, and ankle dorsiflexion, even after adjusting for age, sex, BMI, level of physical activity, and lower back pain using multiple linear regression models. Additionally, HTLV-1-infected individuals without myelopathy demonstrated reduced flexibility in movements: knee flexion, dorsiflexion, and ankle plantar flexion. Conclusions Individuals with TSP/HAM demonstrated reduced flexibility in most of the movements evaluated by the pendulum fleximeter. Additionally, HTLV-1-infected individuals without myelopathy demonstrated reduced knee and ankle flexibility, potentially representing a marker of myelopathic development.

Resumo Antecedentes A flexibilidade é fundamental para a execução harmoniosa dos movimentos articulares. Embora a disfunção do músculo esquelético em pacientes com HTLV-1 possa interferir na mobilidade, não está claro se esses pacientes apresentam flexibilidade reduzida. Objetivo Avaliar as diferenças de flexibilidade entre os indivíduos infectados com e sem mielopatia e o grupo controle sem infecção HTLV-1. Também investigamos se idade, sexo, índice de massa corporal (IMC), nível de atividade física ou dor lombar influenciam a flexibilidade em indivíduos infectados pelo HTLV-1. Métodos A amostra foi composta por 56 adultos, dos quais 15 não possuíam HTLV-1, 15 possuíam HTLV-1 sem mielopatia e 26 possuíam TSP/HAM. A flexibilidade foi avaliada por meio do teste de sentar e alcançar e do flexímetro de pêndulo. Resultados Não foram observadas diferenças na flexibilidade entre os grupos com e sem mielopatia no teste de sentar e alcançar. Os resultados do flexímetro pendular dos indivíduos com TSP/HAM apresentaram a menor flexibilidade entre os grupos em relação à flexão do tronco, flexão e extensão do quadril, flexão do joelho e dorsiflexão do tornozelo, mesmo após ajuste para idade, sexo, IMC, nível de atividade física e dor lombar usando modelos de regressão múltipla linear. Além disso, os indivíduos infectados pelo HTLV-1 sem mielopatia demonstraram redução da flexibilidade nos movimentos de flexão do joelho, dorsiflexão e flexão plantar do tornozelo. Conclusão Indivíduos com TSP/HAM demonstraram redução da flexibilidade na maioria dos movimentos avaliados pelo flexímetro pendular. Além disso, indivíduos infectados pelo HTLV-1 sem mielopatia demonstraram redução da flexibilidade do joelho e tornozelo, representando potencialmente um marcador de desenvolvimento mielopático.

Seroprevalence of maternal peripartum human T-cell lymphotropic virus type-1 infection: a systematic review and meta-analysis of the Nigerian literature.

BACKGROUND: The peripartum period is both a highly vulnerable stage and a significant indicator of a population's health status. Interest is increasing in human T-cell lymphotropic virus type-1 (HTLV-1) transmission due to its adverse health impacts. However, nationally representative data on HTLV-1 that are important for health planning are unavailable for this subpopulation. PURPOSE: This study aimed to conduct a pooled estimate of HTLV-1 prevalence among pregnant women in Nigeria to quantify its clinical burden and public health implications. METHODS: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis 2020 statement. RESULTS: After a systematic review of the Nigerian literature, 12 studies (2,821 pregnant or postnatal women) were included in the final evidence synthesis. The estimated HTLV-1 prevalence in Nigerian peripartum women following a positive screening test by enzyme-linked immunosorbent assay was 5.44% (95% confidence interval [CI], 3.16%-9.20%). A subgroup analysis of the 2 major regions showed a slightly higher prevalence in the Western versus Southern region (5.55% [95% CI, 2.49%-11.87%]; and 4.91% [95% CI, 2.11%-11.02%]; P=0.84). However, a subgroup analysis by geopolitical zone revealed that Southwestern and Northwestern Nigeria had the highest prevalence (9.23% [95% CI, 4.35%-18.55%; I2=93%] and 7.15% [95% CI, 1.54%-27.54%]; I2=92%). Our decade-old subgroup analysis found inconsistencies in the HTLV-1 prevalence. Furthermore, our literature review revealed a prevalence of HTLV infection among patients with various clinical types of lymphomas/leukemias and myelopathy of 2%-22%. CONCLUSION: These findings have important implications in defining the epidemiological patterns of HTLV-1 infection in Nigeria. They also suggest the presence of HTLV-endemic clusters near low-endemic areas, even within the same geopolitical zones.