Human T Lymphotropic Virus 1-Associated Myelopathy: Overview of Human T Cell Lymphotropic Virus-1/2 Tests and Potential Biomarkers.

Human T cell lymphotropic virus (HTLV)-1-associated myelopathy is a chronic, disabling inflammatory disorder of the spinal cord caused by HTLV-1 infection. The diagnosis of HTLV-1-associated myelopathy (HAM) is based on clinical and laboratorial findings. The disease is characterized by the presence of spastic paraparesis associated with detection of anti-HTLV-1 antibodies or HTLV-1 genomes in blood and cerebrospinal fluid (CSF). New inflammatory markers have been proposed for the diagnosis and assessment of the prognosis of HAM. We reviewed the laboratory diagnostic and potential surrogate markers for HAM. The serological screening tests for detection of anti-HTLV-1/2 antibodies are highly sensitive and specific, but confirmation and typing of HTLV-1 or HTLV-2 infection by other serological or molecular methods are essential. Detection of intrathecal anti-HTLV-1 antibodies and quantification of the HTLV-1 provirus in CSF provide additional evidence for diagnosis especially in atypical cases or where alternative causes of neuroinflammation cannot be excluded. The CXC motif chemokine ligand 10 and neopterin in serum and CSF are now emerging as inflammatory markers with prognostic value and for HAM monitoring and management. In addition, measures of neurodegeneration, such as neurofilament light chain in the CSF and blood, may also contribute to the HAM prognosis. This review is useful for clinicians and researchers evaluating potential benefits and limitations of each biomarker in clinical practice. The advent of new markers makes it necessary to update the criteria for the best evidence-based approach and for worldwide consensus regarding the use of diagnostic and surrogate markers for HAM.

Development and Validation of a Rapid Screening Test for HTLV-I IgG Antibodies.

Initial diagnosis of human T cell lymphotropic virus (HTLV) infections is mainly based by detecting antibodies in plasma or serum using laboratory-based methods. The aim of this study was to develop and evaluate a rapid screening test for HTLV-I antibodies. Our rapid screening test uses HTLV-I p24 antigen conjugated to gold nanoparticles and an anti-human IgG antibody immobilized to a nitrocellulose strip to detect human HTLV-I p24-specific IgG antibodies via immunochromatography. Performance of the rapid screening test for HTLV-I was conducted on a total of 118 serum specimens collected in Salvador, Bahia, the epicenter for HTLV-1 infection in Brazil. Using a Western blot test as the comparator, 55 serum specimens were HTLV-I positive, 5 were HTLV-I and HTLV-II positive, and 58 were negative. The sensitivity of the rapid screening test for HTLV-1 was 96.7% and the specificity was 100%. The rapid screening test did not show cross-reaction with serum specimens from individuals with potentially interfering infections including those caused by HTLV-II, HIV-I, HIV-II, hepatitis A virus, hepatitis B virus, hepatitis C virus, herpes simplex virus, Epstein-Barr virus, SARS-CoV-2, Chlamydia trachomatis, Neisseria gonorrhoeae, Treponema pallidum, Toxoplasma gondii, and Plasmodium falciparum. The rapid screening test also did not show cross-reaction with potentially interfering substances. Strategies for HTLV diagnosis in non- and high-endemic areas can be improved with low-cost, rapid screening tests.

[Differentiating Between HTLV-1 Associated Myelopathy and Amyotrophic Lateral Sclerosis: A Case Report].

We present the case of a 72-year-old woman with slowly progressive spastic paraplegia and painful muscle spasms of the lower limbs. Spastic paraplegia began in the left lower extremity and extended to the right lower extremity 4 months later. We considered the diagnosis of amyotrophic lateral sclerosis (ALS) because of the left-dominant spastic paraplegia of bilateral lower limbs and due to the presence of fasciculation, hyperreflexias, and pathological reflexes. However, cerebrospinal fluid (CSF) examination revealed that cell count and protein values were increased. The patient also had an increased titer of anti-HTLV-1 antibodies in serum and CSF and was diagnosed with HTLV-1 associated myelopathy (HAM). She was treated with steroids, and her symptoms improved. Distinguishing HAM from ALS may be difficult because HAM may present with unilateral spastic paralysis and may be accompanied by fasciculation. Careful and accurate evaluation is necessitated to differentiate between these conditions for a conclusive diagnosis. (Received 1 March, 2021; Accepted 26 April, 2021; Published 1 September, 2021).

Seroprevalence of human T-lymphotropic virus infection among blood donors in China: a first nationwide survey.

BACKGROUND: So far, the prevalence of human T-lymphotropic virus (HTLV) type 1 and 2 in some highly populated countries such as China is still unknown. In this study, a multi-center nationwide serological survey was designed and performed, to reveal the seroprevalence of HTLV infection among Chinese blood donors. RESULTS: Among 8,411,469 blood donors from 155 blood establishments, 435 were finally confirmed as HTLV carriers. The prevalence of HTLV infection in China varied in different provinces: Fujian had the highest prevalence of 36.240/100,000 (95% CI 31.990-41.050) and eleven provinces did not find HTLV-seropositive donors in the three years. no HTLV-2 infection was found. The overall prevalence of HTLV-1 in China decreased from 2016 to 2018. Female was identified as an independent risk factor of HTLV infection in China. Besides, seroconversion was observed in two of seven seroindeterminate donors 85 and 250 days after their last donation, respectively. CONCLUSIONS: The seroprevalence of HTLV infection in most areas of China among blood donors is quite low, but it varies significantly in different geographic areas. Screening anti-HTLV-1/2 antibody and follow-up of serointederminate donors are essential to ensure blood safety especially in areas where we have found HTLV infected donors.

Estimation of the window period of human T-cell leukemia virus type 1 and 2 tests by a lookback study of seroconverters among Japanese voluntary blood donors.

BACKGROUND: Japan is endemic for human T-cell leukemia virus type 1 (HTLV-1), and the horizontal transmission of HTLV-1 is often reported. However, the window period (WP) for serologic or molecular screening is unclear. STUDY DESIGN AND METHODS: Results for anti-HTLV-1 screening and confirmatory tests obtained from 648 591 repeated blood donors in the Kyushu district, one of the most endemic areas of HTLV-1 in the world, were evaluated. A lookback study was conducted for seroconverters. RESULTS: During 2012 to 2019, 436 seroconverters (155 men, 281women) were identified with use of a screening chemiluminescence enzyme-immunoassay (CLEIA) and multiple confirmatory tests. Because the period between the latest seronegative donation and seroconversion was highly variable (2.1-276.7 months), 19 cases that seroconverted within 6 months were subjected to the analysis. The WP of the particle agglutination assay and CLEIA was estimated to be 2.2 ± 0.6 and 2.6 ± 1.7 months, respectively. The WP of the indirect immunofluorescence assay was 4.8 ± 6.5 months. Although the WP of western blotting was estimated to be 6.3 ± 8.7 months, four cases were still indeterminate through the study period. Chemiluminescence and line immunoassays, the current screening and confirmatory tests used in the Japanese blood program, showed the shortest WP of 2.2 ± 0.6 months. The WP of real-time polymerase chain reaction for HTLV-1 was estimated to be 4.1 ± 7.8 months. CONCLUSIONS: The WP in commercially available testing systems for HTLV-1/2 was determined for natural infection among repeated blood donors. Considering the HTLV-1 WP will help increase transfusion safety and facilitate the accurate diagnosis of HTLV-1 infection.

The case of a 37-year-old male with trouble ambulating and incontinence.

A 37 year-old previously healthy man from Jamaica presented with 2-3 months of progressive trouble ambulating and incontinence. By 1 month prior to arrival he was wheelchair bound and unable to ambulate even with assistance. He started to wear a diaper for bladder and bowel incontinence. He also complained of painless numbness in his legs over the same period of time. His exam is notable for marked weakness and spasticity in his legs, with hyper-reflexia and clonus. He has a sensory level at the level of the umbilicus. An MRI shows a longitudinally extensive T2 signal change throughout the thoracic cord. His cerebrospinal fluid is mildly inflammatory. His HTLV-1 antibody test is reactive.

Tackling HTLV-1 infection in ophthalmology: a nationwide survey of ophthalmic care in an endemic country, Japan.

INTRODUCTION: Japan is the most endemic of the developed nations in terms of human T-lymphotropic virus type 1 (HTLV-1) infection. Japan has been tackling HTLV-1 infection and has made remarkable progress. In ophthalmology, awareness of the association between HTLV-1 infection and uveitis has been increasing since the 1990s, when the relationship was first established. Here, we describe a nationwide survey and analysis of the current state of medical care for HTLV-1-associated uveitis (HAU) at ophthalmic facilities in Japan. METHODS: A questionnaire survey covered all university hospitals in Japan that were members of the Japanese Ophthalmological Society and all regional core facilities that were members of the Japanese Ocular Inflammation Society. Survey data were collected, and nationwide data on the state of medical care for HAU were tallied and analysed. RESULTS: Of the 115 facilities, 69 (60.0%) responded. HAU was most commonly diagnosed 'based on blood tests and characteristic ophthalmic findings'. Overall, 86.8% of facilities perform testing for HTLV-1 antibodies during medical care for diagnosing uveitis, with 58.3% routinely performing testing. Facilities with experience in providing medical care for HAU accounted for 67.6%. The survey also revealed that 85.5% of facilities had seen no decrease in the number of patients with HAU. CONCLUSIONS: In the two decades since the establishment of HAU as a pathological entity, the majority of facilities in Japan have started performing testing for HTLV-1 antibodies when considering differential diagnoses for uveitis. Our data suggest that providing information on HTLV-1 infection to ophthalmologists in Japan has been successfully implemented.

Surveillance of human retroviruses in blood samples from patients with hepatitis B and C in São Paulo, Brazil.

INTRODUCTION: Human retroviruses and the hepatitis B and C viruses (HBV and HCV, respectively) share routes of transmission; thus, coinfections occur and could alter subsequent disease outcomes. A preliminary study on human T-lymphotropic virus types 1 and 2 (HTLV-1/2) in serum samples from HBV- and HCV-infected individuals in São Paulo revealed 1.3% and 5.3% rates of coinfection, respectively. These percentages were of concern since they were detected in HTLV-endemic regions and in high-risk individuals in Brazil. The present study was conducted to extend and confirm these data. METHODS: HTLV-1/2 and human immunodeficiency virus (HIV) infection status were identified in 1,984 sera for HBV and HCV viral load quantification - 1,290 samples from HBV-infected individuals (53.3% men, mean age: 47.1 years) and 694 samples from HCV-infected individuals (56.3% men, mean age: 50.1 years). HTLV-1/2 antibodies were detected by enzyme immunoassay, followed by western blotting and line immunoassay; HIV infection was detected by enzyme immunoassay. RESULTS: HTLV-1/-2 infection was detected in 1.9% HBV-infected individuals (0.7% HTLV-1 and 1.2% HTLV-2) and in 4.0% (2.4% HTLV-1 and 1.6% HTLV-2) HCV-infected individuals; HIV infection was detected in 9.2% and 14.5%, respectively. Strong associations with HTLV and HIV, male sex, and older age were found in HBV/HTLV and HCV/HTLV-coinfected individuals (p<0.05). CONCLUSIONS: HTLV-1 and HTLV-2 were confirmed to be prevalent in individuals with HBV and HCV in São Paulo; coinfected individuals deserve further clinical and laboratory investigation.

Prevalence of human T-cell lymphotropic virus and the socio-demographic and risk factors associated with the infection among post-natal clinics women in Zaria, Nigeria.

Introduction: Human T-cell lymphotropic virus has long been associated with Adult T-cell leukemia/lymphoma, HTLV-associated myelopathy/tropical spastic paraparesis, and hairy cell leukemia. Aim: The aim was to determine the prevalence of HTLV antibodies as well as the socio-demographic and risk factors associated with HTLV among women attending postnatal clinics in Zaria. Methodology: A total of 190 samples were collected within the months of January and June 2017 and qualitative determination of antibodies for HTLV in serum was performed by an antigen sandwich enzyme immunoassay method. Results: The study established an HTLV infection prevalence of 3.2% (6/190). Higher prevalence was observed among women from polygamous families [6.2% (4/64)], the self-employed [6.5% (4/62)], those in age group of 15-25 years [6.2% (5/72)] and women with only primary education [5.9% (2/32)] although the associations were not statistically significant. Similarly, there was no significant association between HTLV infection and history of family cancer (P = .629), intravenous drug use (P = .682), sharing of sharp objects (P = .596,) and history of X-ray exposure (P = .366), except for history of previous blood transfusion which shows significant association (P = .010). Conclusion: The study established a prevalence an HTLV of 3.2% that HTLV in Zaria therefore routinely screened is necessary.

The prevalence of human T-cell leukemia virus in blood donors in China.

BACKGROUND: China has not yet incorporated routine human T-lymphotropic virus (HTLV)-1/2 blood donor screening, even though HTLV has been reported in the southeastern coastal region. This study was conducted to investigate the prevalence of HTLV in five major regions across of China. METHODS: From January 2016 to December 2017, blood samples were collected in 20 blood centers located in different regions of China. These samples were screened for HTLV-1/2 antibodies using enzyme-linked immunosorbent assay (ELISA). If the test samples were reactive, the samples were confirmed with a western blot (WB) assay. If the results of WB were indeterminate, the donor was interviewed after a minimum lapse of 8 weeks. All follow-up samples from donors were tested for anti-HTLV-1/2 with ELISA and WB. RESULTS: There were 875,453 donor samples tested for anti-HTLV-1/2 by ELISA. In all, 365 samples tested negative, 22 samples tested positive by WB, and 14 samples with HTLV status undetermined due to being lost to follow-up. The prevalences were 11.09, 5.96, 3.16, 2.88 and 0.98 per 100,000 in Xiamen, Changsha, Beijing, Shenzhen, and Nanjing blood center, respectively. The prevalences were 0 per 100,000 for all 15 other blood centers. There was significant differences in the prevalence of HTLV in different regions of China (p = 0.0011). CONCLUSION: In China, HTLV-1 confirmed positive donors are mainly from southeastern coastal areas. It may be necessary to conduct HTLV screening in these areas to reduce the risk of transfusion-transmitted HTLV.

Seroprevalence of HTLV-1/2 Among Voluntary Blood Donors in Vietnam.

Infection with human T lymphotropic virus (HTLV), although asymptomatic in most cases, can lead to severe illnesses, such as adult T cell leukemia/lymphoma or myelopathy/tropical spastic paraparesis. HTLV can be transmitted by whole-blood (WB) transfusion. The prevalence of HTLV among blood donor populations has not been characterized in Vietnam, although the screening has been partially implemented on voluntary basis since 2016. To determine the seroprevalence of HTLV-1/2 among blood donors, a total of 14,819 healthy blood donors in northern, central, and southern Vietnam and 1,003 samples from hepatitis B surface antigen (HbsAg), anti-hepatitis C (anti-HCV), or HIV Ag/Ab reactive blood donors were screened for anti-HTLV-1/2 antibodies by a chemiluminescence immunoassay using the Abbott ARCHITECT rHTLV-I/II assay. The anti-HTLV-1/2 repeat reactive (RR) samples were further tested by immunoblot (IB) method using MP Biomedicals HTLV Blot 2.4 for confirmation and differentiation of HTLV-1/2 infection. Proviral HTLV subgenomic amplification of the gag and tax regions was performed on the available WB RR samples (N = 11) by polymerase chain reaction (PCR). Among 14,819 blood donors, 34 samples (0.23%) were RR for anti-HTLV-1/2 antibodies, but only 1 case was confirmed HTLV-2 positive (0.0067%) and 5 cases were classified as indeterminate (0.034%) by IB. The RR rate was 0.39% among HBsAg/anti-HCV/HIV reactive sample groups, but none of them was confirmed by IB. Subgenomic PCR failed to amplify proviral DNA from WB samples of 11 RR samples. HTLV-1/2 prevalence was found to be low among blood donors in the study. Continued vigilance remains essential to maintain a low transfusion-transmitted risk in Vietnam.

Human T-cell lymphotropic virus type I and II seroprevalence among volunteer blood donors in Thailand.

Human T-cell lymphotrophic virus type I and II (HTLV-I/II) are closely related but distinct retroviruses that can infect humans. Both the viruses can be transmitted via transfusion of contaminated blood components. HTLV pre-transfusion screening is not mandatory in Thailand until now. Current epidemiological data for HTLV prevalence is still lacking since the past surveys were done more than a decade ago. The main objective of this study was to determine the seroprevalence of HTLV-I/II among voluntary blood donors in Thailand. 11,057 volunteer blood donors were screened for HTLV-I/II antibodies using the ARCHITECT rHTLV-I/II chemiluminescent immunoassay (CLIA). Initial-reactive (IR)  samples were subjected to repeat duplicate testing and were also sent for confirmatory testing at Korean Red Cross Society (KRC), Seoul or National Serology Reference Laboratories (NRL), Australia using alternate HTLV serological assays and immunoblot and/or specific nucleic acid testing respectively. Out of 11,057 plasma samples, 10,080 were low-risk seronegative donors and 977 were first-time/high-risk donors. Twenty of 24 IR samples were repeatedly reactive (RR) in low-risk seronegative donors group. On confirmatory testing of these 24 IR by immunoblot, 13 indeterminate and 11 negative results were observed. One out of 977 samples from first-time/high-risk donors was RR for anti-HTLV-I/II antibodies. This sample was co-reactive for HBsAg, but negative for HTLV by EIA or in-house HTLV-I qPCR. The ARCHITECT rHTLV-I/II assay exhibited a specificity of 99.93% in low-risk donors and 99.90% among high-risk donors. This study concluded that HTLV-I/II prevalence is low among blood donors in Thailand. But periodic surveillance should be continually conducted to ensure high blood safety standards in the country.

Moderate endemicity of the human T-lymphotropic virus infection in the metropolitan region of Belém, Pará, Brazil. / Moderada endemicidade da infecção pelo vírus linfotrópico-T humano na região metropolitana de Belém, Pará, Brasil.

INTRODUCTION: The spread of the HTLV infection in families living in the metropolitan area of Belém, Pará, Brazil, and the lack of studies in the general population requires studies to better understand its prevalence in the region. METHODS: An anti-HTLV-1/HTLV-2 antibodies test was carried out on random adults in public places in Belém between November 2014 and November 2015. A proviral DNA test detected if the person was infected, and then a clinical evaluation and an intrafamilial investigation were carried out. RESULTS: Of the 1059 individuals being investigated, 21 (2.0%) had seroreagent samples, 15 (1.4%) had HTLV-1, 5 (0.5%) had HTLV-2, and proviral DNA was undetectable in one case. The mean age of the infected people (57.2) was higher than that of those that were uninfected (46.2) (p = 0.0010). The prevalence of infection increased with age, especially in individuals with a family income equal to or less than a minimum wage. Intrafamilial transmission seems to have occurred in all of the families being studied. Among the patients with HTLV-1, 30% (3/10) already had some symptom related to the infection. DISCUSSION: The increase in prevalence rates according to age may be due to late seroconversion of a previously acquired infection, or the cumulative risk of new infections, especially in women. CONCLUSION: There was a moderate prevalence of the HTLV infection among adult individuals from the metropolitan area of Belém, with a predominance of HTLV-1. This infection was associated with low income and increasingly older women. It also presented intrafamily spread and negligence in the diagnosis of associated diseases.

INTRODUÇÃO: A disseminação da infecção pelo vírus linfotrópico-T humano (HTLV) em famílias da área metropolitana de Belém, Pará, Brasil, e a ausência de estudos na população em geral requisitam investigações que esclareçam melhor a sua prevalência na região. METODOLOGIA: Foi realizada pesquisa de anticorpos anti-HTLV-1/HTLV-2 em indivíduos adultos transeuntes de logradouros públicos de Belém, entre novembro de 2014 e novembro de 2015. A infecção foi confirmada por pesquisa de DNA proviral e foi realizada avaliação clínica e investigação intrafamiliar dos infectados. RESULTADOS: Dos 1.059 indivíduos investigados, 21 (2,0%) apresentaram amostras sororeagentes, 15 (1,4%) confirmados para HTLV-1, 5 (0,5%) para HTLV-2 e o DNA proviral foi indetectável em 1 caso. A média de idade dos infectados (57,2) foi maior que a dos não infectados (46,2) (p = 0,0010). A infecção aumentou com a idade e se destacou nos indivíduos com renda familiar menor ou igual a um salário mínimo. A transmissão intrafamiliar parece ter ocorrido em todas as famílias investigadas. Dentre os portadores de HTLV-1, 30% (3/10) já apresentavam algum sintoma relacionado à infecção. DISCUSSÃO: O aumento da infecção de acordo com a idade pode ocorrer por soroconversão tardia de infecção pré-adquirida ou pelo risco cumulativo de novas infecções, sobretudo em mulheres. CONCLUSÃO: A infecção por HTLV demonstrou moderada prevalência na população estudada, com predomínio do HTLV-1. Essa mostrou-se associada à baixa renda e ao aumento da idade das mulheres. Também apresentou disseminação intrafamiliar e negligência no diagnóstico das doenças associadas.

Phylogeny of human T-lymphotropic virus-1 subtypes in Guinea-Bissau.

Background: Human T-cell leukaemia/lymphoma virus type 1 (HTLV-1) was the first human retrovirus discovered and there is an estimate of 15-20 million infected worldwide. Endemic areas are Japan, West Africa, Central Africa, South America, the Caribbean, Middle East, Australia and the Pacific Islands. In Guinea-Bissau, adult HTLV-1 prevalence is 2-3%, and higher among HIV-infected patients. Materials and methods: Blood samples were collected in a recent HIV/HTLV survey in Bissau, the capital of Guinea-Bissau. Initially, participants were tested for HTLV serologically. The p24 and LTR regions of the proviral genome were then attempted sequenced. Sequences were analysed phylogenetically and compared with reference sequences for HTLV-1. Results: A total of 3% (78/2583) participants were positive on chemiluminesent assay, six additional samples came from another study. Of the 84 seropositive participants we successfully performed sequencing on samples, from 66 participants, 17 were positive for LTR only, one for p24 only and 48 for both. Sequences were in subgroup D of HTLV-1a cosmopolitan, while HTLV-1g was present in one participant. Conclusion: HTLV-1a subgroup D and, to a lesser extent HTLV-1g, is present in Guinea-Bissau and sequences are very similar, especially within households. Presence of HTLV-1g indicates monkey-to-man zoonotic events and at least two circulating HTLV strains in Guinea-Bissau. New sequences accession numbers: MG387979-MG388043 for LTR and MG388044-MG388092 for p24.

Development and Evaluation of a Novel ELISA for Detection of Antibodies against HTLV-I Using Chimeric Peptides.

We aimed to develope a peptide-based indirect ELISA to detect antibodies against Human T-lymphotropic virus type I (HTLV-I). Two chimeric peptides (CP-1 and CP-2) were designed using linear immunodominant epitopes of gp-46-I, and gp21-I proteins, according to the sequence from Uniprot database. These peptides were studied initially in the ELISA using infected sera. The most promising peptideCP-1, was used to develop a peptide ELISA for detection of HTLV-I infected sera. The optimal conditions for CP-1ELISA were: the optimum coating buffer was 100mM NaHCO3, pH 9.6; coating peptide concentration was 10 µg/mL; the optimal blocking buffer was5% fetal bovine serum (FBS); the secondary antibody concentration was 1:2000; and serum dilution was 1:20. 20serum samples from HTLV-I infected patients were evaluated by ELISA developed. CP-1 showed high antigenicity while lacking any cross-reactivity with normal human sera. The results of evaluations indicated that in comparison with commercial ELISA, CP-1 ELISA showed good sensitivity and specificity. With further validation, CP-1as described in the present study could be introduced as novel reliable and cost-effective candidates for the high-specific screening of HTLV-I/-II infections in endemic regions.

Temporal trends in Human T-Lymphotropic virus 1 (HTLV-1) associated myelopathy/tropical spastic paraparesis (HAM/TSP) incidence in Martinique over 25 years (1986-2010).

BACKGROUND: Human T-lymphotropic virus type 1 (HTLV-1) has been discovered in 1980 and has been linked to tropical spastic paraparesis (HAM/TSP) in 1985 in Martinique. There is no data on HAM/TSP incidence trends. We report, in the present work, the temporal trends incidence of HAM/TSP in Martinique over 25 years. METHODS: Martinique is a Caribbean French West Indies island deserved by a unique Neurology Department involved in HAM/TSP diagnosis and management. A registry has been set up since 1986 and patients diagnosed for a HAM/TSP were prospectively registered. Only patients with a definite HAM/TSP onset between 1986 and 2010 were included in the present study. The 25-year study time was stratified in five-year periods. Crude incidence rates with 95% confidence interval (95%CI) were calculated using Poisson distribution for each period. Age-standardized rates were calculated using the direct method and the Martinique population census of 1990 as reference. Standardized incidence rate ratios with 95% CIs and P trends were assessed from simple Poisson regression models. Number of HTLV-1 infection among first-time blood donors was retrospectively collected from the central computer data system of the Martinique blood bank. The HTLV-1 seroprevalence into this population has been calculated for four 5-year periods between 1996 and 2015. RESULTS: Overall, 153 patients were identified (mean age at onset, 53+/-13.1 years; female:male ratio, 4:1). Crude HAM/TSP incidence rates per 100,000 per 5 years (95%CI) in 1986-1990, 1991-1995, 1996-2000, 2001-2005 and 2006-2010 periods were 10.01 (6.78-13.28), 13.02 (9.34-16.70), 11.54 (8.13-14.95), 4.27 (2.24-6.28) and 2.03 (0.62-3.43). Age-standardized 5-year incidence rates significantly decreased by 69% and 87% in 2001-2005 and 2006-2010 study periods. Patients characteristics did not differ regarding 1986-2000 and 2001-2010 onset periods. Between 1996-2000 and 2011-2015 study periods, the HTLV-1 seroprevalence significantly decreased by 63%. CONCLUSION: Martinique faces a sudden and rapid decline of HAM/TSP incidence from 2001 in comparison to 1986-2000 periods. Reduction of HTLV-1 seroprevalence, that may result from transmission prevention strategy, could account for HAM/TSP incidence decrease.

Prevalence of Human T-lymphotropic virus type 1 (HTLV-1) Infection in Patients with Hematologic Disorders and Non-Hematologic Malignancies in a Tertiary Referral Hospital.

BACKGROUND: Human T-lymphotropic virus type 1 (HTLV-1) was the first retrovirus identified in human. The current evidence is quite scarce regarding the potential role of HTLV-1 in pathogenesis of hematologic disorders and non-hematologic malignancies. OBJECTIVES: The aim of this study is to evaluate the prevalence of HTLV-1 infection in patients with hematologic disorders and non-hematologic malignancies. METHODS: This cross-sectional study was conducted on 505 cases of definite diagnosis of hematologic disorders including malignancies as well as non-malignant disorders such as polycythemia and myelofibrosis and non-hematologic malignancies referred to the hematology and medical oncology ward at Army Hospital 501 from January 2015 to January 2016. A 3-mL blood specimen was collected from each patient and tested for the presence of anti-HTLV-1 antibodies using enzyme-linked immunosorbent assay (ELISA). Data were analyzed using SPSS software package version 19 (IBM, New York, USA). Data are presented as mean ± SD if normally distributed and otherwise as median (range). RESULTS: Totally, 242 (48%) males and 263 (52%) females with a mean ± SD age of 52.09 ± 16.24 were enrolled in this study. In total, there were 9 (1.78%) cases positive for HTLV-1 infection including 4 males and 5 females. Seven out of 287 (2.4%) patients with hematologic disorders were infected by HTLV-1. In non-hematologic malignancies, 2 out of 211 cases were positive (0.9%). There was no HTLV-1 positive case in 7 patients with both hematologic and non-hematologic disorders. The difference in HTLV-1 infection prevalence between patients with hematologic disorders and non-hematologic malignancies was not statistically significant different (P = 0.31). There was no association between sex and transfusion history with HTLV-1 infection in this population (P = 0.9 and 0.7, respectively). CONCLUSIONS: Our study revealed that the prevalence of HTLV-1 in hematologic disorders is higher than the general population. Further larger prospective studies are recommended to corroborate the current evidence.

Comparative performances of serologic and molecular assays for detecting human T lymphotropic virus type 1 and type 2 (HTLV-1 and HTLV-2) in patients infected with human immunodeficiency virus type 1 (HIV-1).

The present study evaluated several techniques currently available (commercial kits and in-house assays) for diagnosing human T lymphotropic viruses types 1 and 2 in two groups of patients enrolled at HIV/AIDS specialized care services in São Paulo: Group 1 (G1), n=1608, 1237 male/371 female, median age 44.3 years old, majority using highly active antiretroviral therapy (HAART); G2, n=1383, 930 male/453 female, median age of 35.6 years old, majority HAART naïve. Enzyme immunoassays [(EIA) Murex and Gold ELISA] were employed for human T lymphotropic viruses types 1 and 2 screening; Western blotting (WB), INNO-LIA (LIA), real-time PCR pol (qPCR), and nested-PCR-RFLP (tax) were used to confirm infection. Samples were considered human T lymphotropic viruses types 1 and 2 positive when there was reactivity using at least one of the four confirmatory assays. By serological screening, 127/2991 samples were positive or borderline, and human T lymphotropic virus infection was confirmed in 108 samples (three EIA-borderline): 56 human T lymphotropic virus type 1 [G1 (27)+G2 (29)]; 45 human T lymphotropic virus type 2 [G1 (21)+G2 (24)]; one human T lymphotropic virus type 1+human T lymphotropic virus type 2 (G2); six human T lymphotropic virus [G1 (2)+G2 (4)]. Although there were differences in group characteristics, human T lymphotropic viruses types 1 and 2 prevalence was similar [3.1% (G1) and 4.2% (G2), p=0.113]. The overall sensitivities of LIA, WB, qPCR, and PCR-RFLP were 97.2%, 82.4%, 68.9%, and 68.4%, respectively, with some differences among groups, likely due to the stage of human T lymphotropic virus infection and/or HAART duration. Indeterminate immunoblotting results were detected in G2, possibly due to the seroconversion period. Negative results in molecular assays could be explained by the use of HAART, the occurrence of defective provirus and/or the low circulating proviral load. In conclusion, when determining the human T lymphotropic virus infection, the findings highlight that there is a need to consider the blood samples with borderline results in screening assays. Of all the tested assays, LIA was the assay of choice for detecting human T lymphotropic virus type 1 and human T lymphotropic virus type 2 in human immunodeficiency virus type 1-infected patients.