Human T-lymphotropic virus type I infection in the Solomon Islands

To ascertain the prevalence of human T-lymphotropic virus type I (HTLV-I) infection and the occurrence of diseases caused by HTLV-I in the Solomon Islands, we tested 1141 sera from 851 patients (317 females and 534 males), who were hospitalized at the Central Hospital in Honiara between February 1984 and November 1988, for antibodies to HTLV-I using an enzyme-linked immunosorbent assay (ELISA). Sera from 69 of 81 ELISA-positive patients and from 56 ELISA-negative patients were then tested by Western analysis. As verified by strict Western immunoblot criteria, the overall HTLV-I seroprevalence was 2.2% (19/851). Age- and gender-specific prevalence data indicated an age-related acquisition of infection with no sexual predominance. No diagnosis category was over-represented among the seropositive patients. HTLV-I-specific antibodies were found in serum and cerebrospinal fluid samples from one of six patients with spastic paraparesis. As in other Melanesian populations, the majority of ELISA-positive sera could not be confirmed by Western analysis. Reactivity to three or more gag-encoded proteins was found in 85% (45/53) of ELISA-positive, Western blot-indeterminate sera, and 30% (16/53) reacted to p19 and an env gene product but lacked reactivity to p24. Whether or not the high frequency of indeterminate HTLV-I Western immunoblots in the Solomon Islands is indicative of incomplete specific reactivity to HTLV-I or the existence of antigenically related retroviruses is being investigated.

Diagnosis of HAM/TSP based on CSF proviral HTLV-I DNA and HTLV-I antibody index

The contribution of human T-cell lymphotropic virus (HTLV-I) DNA by PCR in CSF and the intrathecal synthesis of antibodies to HTLV-I by the antibody index (AI) to the diagnosis of HTLV-1-associated myelopathy (HAM)/tropical spastic paraparesis (TSP) were evaluated. Cases of spastic paraparesis compatible with HAM/TSP had increased AI for HTLV-I (60/73) and HTLV-I proviral sequences in CSF (25/27). Among 27 patients with other neurologic diseases, three had increased AI and another three had positive HTLV-I DNA in CSF. Thus, the combination of PCR for proviral DNA and AI for HTLV-I in CSF provides consistent criteria for the diagnosis of HAM/TSP.

Juvenile human T lymphotropic virus type 1-associated myelopathy

We report the cases of 5 adolescents with human T lymphotropic virus type 1-associated myelopathy/tropical spastic paraparesis, acquired in all but 1 case from the mother. The first symptom in all patients was difficulty in running, which was present for many years before the final diagnosis was made. Follow-up showed an indolent progression, regardless of treatment strategy.

HTLV-I-associated myelopathy endemic in Texas-born residents and isolation of virus from CSF cells

We report three Texas-born patients with spastic paraparesis and well-documented infection with HTLV-I. CSF examination showed moderate pleocytosis, protein elevation, and elevated IgG index. Oligoclonal bands were present in two patients. On MRI, one patient had frontal lobe lesions that were low intensity on T1- and high intensity on T2-weighted images. HTLV-I immunoblot studies of serum and CSF revealed reactivity to p19, p24, p53, gp46, or gp68 from all three patients. Titration studies of serum and CSF antibodies on ELISA and immunoblot assays indicated an intrathecal virus-specific response. HTLV-I-specific p19 antigen capture assay and polymerase chain reaction (PCR) demonstrated HTLV-I in lymphocyte cultures derived from each patient's peripheral blood mononuclear cells (PBMC) or CSF cells. Using HTLV-I- and HTLV-II-specific pol and gag primers, PCR studies of PBMC cells obtained directly from the patients demonstrated that the patients were infected with HTLV-I and not HTLV-II. These three cases are to our knowledge the only US cases in whom virus isolation from the CSF has been accomplished. Importantly, two patients may be the first US cases of myelopathy arising from endemic infection.

Imaging of human T-lymphotropic virus type I-associated chronic progressive myeloneuropathies

We studied magnetic resonance imaging (MRI) of the head and cervical spine and CT of the head in 46 patients (14 men, 32 women) with chronic progressive myeloneuropathy. The findings were correlated with human T-lymphotropic virus type I (HTLV-I) serology, race, country of origin, and age. We found a female predominance of 2:1. Most patients were aged between 30 and 50 years, and most were Caribbean immigrants and black. There were 9 men and 17 women with blood antibody titers to HTLV-I and 7 men and 15 women with cerebrospinal fluid (CSF) titers. All patients with virus or antibodies in blood or CSF were Caribbean immigrants or black. T2-weighted cranial MRI showed scattered areas of high signal intensity in the cerebral white matter, usually in the periventricular and subcortical areas, but not in the posterior cranial fossa. Cranial CT revealed periventricular low density areas, ventricular enlargement, and atrophy MRI of the cervical spine showed atrophy of the cord. Myelography was normal in all 15 patients examined. No imaging differences were observed between the HTLV-I-positive and -negative patients. These findings, although consistent with demyelination, are not specific.

Treatment of HTLV-I-associated myelopathy with high-dose intravenous gammaglobulin

Fourteen patients with HTLV-1-associated myelopathy were treated with high-dose intravenous gammaglobulin (IVGG). Ten received 10 g/day of IVGG and 4 received 400 mg/kg of body-weight/day of IVGG for 5 consecutive days. Improvement of spastic paraparesis was observed in 10 within 7 days of the commencement of IVGG. The therapeutic effects were sustained for more than 3 weeks in some patients. There were no side effects. Analysis of factors of relevance to the clinical improvement with IVGG showed that the beneficial response was preferentially found in patients having a high CSF titre of anti-HTLV-I antibodies, a high CSF IgG level and a marked brain MRI abnormality.

HTLV type I and HTLV type II infection among Indians and natives from Argentina

Endemic foci for HTLV-II infection have been identified in several Amerindian populations. To determine HTLV-I and/or HTLV-II infection among Amerindians living in Argentina we studied 454 sera or plasmas from Indians and natives from different areas of our country. All samples were tested by the particle agglutination technique, and positive reactions were confirmed by the immunofluorescence assay (IFA). IFA titration was used to differentiate HTLV-I and HTLV-II antibodies. Twenty-three of 222 samples (10.4%) were found positive among the Tobas Indians; 22 samples were typed as HTLV-II and 1 as HTLV-I. Antibodies for HTLV-I were found in the serum and CSF of three natives from Salta with a TSP diagnosis. No positive samples were found among 96 Mapuche Indians and 133 natives from San Luis. Our results indicate that HTLV-II is endemic among the Tobas Indians. In this study, infection by these retroviruses in Argentinian Amerindians seems to have a marked geographic distribution.

A soluble form of tumour necrosis factor receptor in cerebrospinal fluid and serum of HTLV-I-associated myelopathy and other neurological diseases

Paired samples of cerebrospinal fluid (CSF) and serum from 17 patients with human T-cell lymphotrophic virus I (HTLV-I)-associated myelopathy, 5 patients with multiple sclerosis and 11 controls with non-inflammatory disorders (migraine, idiopathic epilepsy and myelopathy of unknown aetiology) were examined by enzyme-linked immunosorbent assay for the presence of the 60-kDa soluble form of tumour necrosis factor receptor (sTNF-R). The results were compared with blood-CSF barrier function, cell count and the intrathecal synthesis of HTLV-I antibodies. No correlation could be demonstrated. High levels of sTNF-R were found in CSF of patients with HTLV-I-associated myelopathy and multiple sclerosis. In addition, intrathecal sTNF-R was also detected in the patients with non-inflammatory diseases, indicating that sTNF-R is definitively a normal constituent of CSF.

Evidence of preferential female prevalence of HTLV-I associated tropical spastic paraparesis in Bahia-Brazil

In order to evaluate the prevalence of HTLV-I infection and its association with tropical spastic paraparesis (TSP) in Bahia, a Northeastern State of Brazil, CSF and sera from TSP patients and CSF and/or sera from some selected groups of individuals were studied. The results seem to indicate a higher prevalence of HTLV-I infection in women than men with TSP and among individuals of HIV risk groups. Some alterations of routine analysis of CSF can suggest HTLV-I infection in TSP patients.

Progressive spastic paraparesis associated with human T-cell leukemia virus type I (HTLV-I)

Patients with progressive spastic paraparesis (PSP), commonly middle-aged women, are distributed throughout the country of Chile. During the three years from 1987 to 1990, we collected 83 cases of PSP from among 225 patients with various neurological diseases. The clinical picture was of a bilateral pyramidal syndrome, with sensory deficits in only 15.5% of the cases, and a slow illness progression in the majority of them. In patients with PSP, antibody to human T-cell leukemia virus type I (HTLV-I) was analyzed by enzyme linked immunosorbent assay (ELISA) and confirmed by western blot analysis. Forty-five (54.2%) patients were anti-HTLV-I antibody positive in cerebrospinal fluid (CSF) and peripheral blood. Among them, 2 patients had leukemia/lymphoma and one had Sjögren syndrome. In the laboratory study of seropositive PSP, mononuclear pleocytosis was found in 35.7%; there was an abnormal increase of the IgG index in 66.6% and an increase in CD2 in blood and CSF, and CD4 in blood. A delayed latency of somatosensory evoked potentials was observed in 90.9%. The neuropsychological study revealed a WAIS with a mean verbal IQ of 80.7 and a mean performance IQ of 84.8. The most impaired items were digit symbol and digit span. Seven subjects (18.9%) with anti-HTLV-I antibody were found among 37 relatives from 19 anti-HTLV-I positive cases of PSP.

Subacute meningoencephalitis associated with human T-lymphotrophic virus type I (HTLV-I). Report of a case

We present a case of subacute meningoencephalitis associated with human T-lymphotrophic virus Type I (HTLV-I) infection, for HTLV-I antibody being positive in serum and cerebrospinal fluid. Necropsy findings disclosed leptomeningeal and parenchymal mononuclear cell infiltration with multinucleate giant cells, which are similar to those seen in subacute encephalitis with acquired immunodeficiency syndrome (AIDS).

The value of CSF analysis for the differential diagnosis of HTLV-I associated myelopathy and multiple sclerosis

Cerebrospinal fluid (CSF) and serum of 17 patients with HAM/TSP (HTLV-I associated myelopathy/tropical spastic paraparesis), six with multiple sclerosis and six with idiopathic epilepsy (non inflammatory control) from Brazil were analysed for the presence of intrathecal synthesis of virus-specific antibodies against measles, rubella, varicella zoster virus and herpes simplex virus by enzyme-linked immunosorbent assay (ELISA). All HAM/TSP and multiple sclerosis cases had an intrathecal immune response (oligoclonal IgG). In HAM/TSP, only 1/17 case showed a polyspecific intrathecal immune response against measles and rubella virus. In multiple sclerosis, specific antibodies against measles and rubella (MRZ response) were observed in all patients but not in the control with idiopathic epilepsy. The diagnostic and theoretical relevance of mono- and polyspecific immune responses is discussed for these chronic neurological diseases.

Specificity of intrathecal IgG synthesis for HTLV-1 core and envelope proteins in HAM/TSP

INTRODUCTION

In patients with human T-cell lymphotropic virus type 1 (HTLV-1) associated myelopathy/tropical spastic paraparesis (HAM/TSP), we investigated the significance of HTLV-1 specific antibodies in the cerebrospinal fluid (CSF).

MATERIAL AND METHODS

The quantities of HTLV-1 specific immunoglobulin G (IgG) in paired CSF and serum were evaluated by a sensitive enzyme immunoassay (EIA). The specificity of antiviral IgG was determined by radioimmunoprecipitation of HTLV-1 antigens.

RESULTS

In 17 of 20 HAM/TSP patients, quantitative evaluation by EIA supplied evidence for antiviral IgG synthesis within the CNS. Radioimmunoprecipitation demonstrated IgG antibodies against HTLV-1 envelope and core proteins in all HAM/TSP CSF and sera tested. Regarding the 3 sample pairs indeterminate in EIA for intrathecal synthesis, 2 showed stronger precipitation of HTLV-1 antigens by CSF IgG than by equal amounts of serum IgG.

CONCLUSION

Intrathecal antibody synthesis specific for both HTLV-1 core and envelope antigens is common in HAM/TSP, thus providing conclusive evidence for an immune response to HTLV-1 within the CNS.

Pathological and virological assessment of acute HTLV-I-associated myelopathy complicated with encephalopathy and systemic inflammation

HTLV-I-associated myelopathy, also known as tropical spastic paraparesis (HAM/TSP), is a chronic inflammatory disease of the spinal cord. Acute cases are uncommon. We report the case of a 41-year-old woman with acute HAM/TSP complicated with encephalitis, an intense inflammatory reaction of the nervous system and lymphocytic infiltration of skeletal muscles, liver, salivary, adrenal and pituitary glands. The immunohistochemical studies of the lymphocytes surrounding blood vessels showed both B- and T-lymphocytes, in similar proportion, with both CD4- and CD8-positive cells. In addition, many perivascular and scattered macrophages were observed. Adult T-cell leukemia/lymphoma (ATL) was ruled out. The marrow aspirate was normal. Serial cerebrospinal fluid (CSF) analysis showed presence of HTLV-I antibodies, but without intrathecal synthesis of specific antibodies. Determination of HTLV-I viral loads demonstrated increased levels in the CSF relative to the peripheral blood and may be associated with widespread inflammation. The pathological and immunological findings may help understand the role of immune-reactive cells in the pathogenesis of HTLV-I-associated myelopathy.

Chronic active VZV infection manifesting as zoster sine herpete, zoster paresis and myelopathy

After lumbar-distribution zoster, an HTLV-1-seropositive woman developed chronic radicular sacral-distribution pain (zoster sine herpete), cervical-distribution zoster paresis and thoracic-distribution myelopathy. Detection of anti-varicella zoster virus (VZV) IgM and VZV IgG antibody in cerebrospinal fluid (CSF), with reduced serum/CSF ratios of anti-VZV IgG compared to normal serum/CSF ratios for albumin and total IgG, proved that VZV caused the protracted neurological complications. Diagnosis by antibody testing led to aggressive antiviral treatment and a favorable outcome.

New findings and symptomatic treatment for neurolathyrism, a motor neuron disease occurring in north west Bangladesh

Neurolathyrism is a form of spastic paraparesis caused by the neuroexcitatory amino acid 3-N-oxalyl-L-2,3-diaminopropanoic acid (beta-ODAP) present in the seeds and foliage of Lathyrus sativus. The disease is irreversible and usually nonprogressive. Tolperisone HCl, a centrally acting muscle relaxant, has been shown to reduce significantly the spasticity in neurolathyrism patients. Sporadic occurrence of HTLV-1 infection (0.9%) and of osteolathyrism was found among the neurolathyrism patients. Osteolathyrism is linked to the consumption of the green shoots of Lathyrus sativus.

HTLV-I associated myelopathy in patients from Brazil and Iran: neurological manifestations and cerebrospinal fluid findings

We analysed sera and cerebrospinal fluid (CSF) of 20 cases of human T-cell lymphotropic virus type (HTLV-I) associated myelopathy/tropical spastic paraparesis (HAM/TSP) from Brazil and Iran and as controls, 16 Brazilian HTLVI seronegative individuals afflicted with other neurological diseases. It was observed in the HAM/TSP patients that: 1) all had an inflammatory reaction within the central nervous system (CNS); 2) 95% (19/20) showed oligoclonal bands reflecting intrathecal IgG synthesis; 3) 85% (17/20) presented a local synthesis of HTLVI antibodies; 4) 35% (7/20) had a measurable immunoglobulin (Ig) synthesis within the CNS. The CSF parameters of the HAM/TSP were compared with the clinical data (age at onset, duration of disease and disability level). Our data prove that CSF analysis is important for the diagnosis of HAM/TSP. There is no association between the severity of the disease and CSF findings.

HTLV-1 and myelopathy in Salvador (northeastern Brazil): a case control study

The principal aim of the study was to determine the degree of association between cerebrospinal fluid (CSF) that is positive for HTLV-1 and myelopathy in Salvador, Brazil. From the same hospital, twenty-eight cases of myelopathy and twenty-eight cases showing no neurological disorder were studied using blind selection matched 1:1 by age and sex. The twenty-eight pairs underwent HTLV-1 serology tests. In those with a positive result, anti-HTLV-1 antibodies were investigated in the CSF. The ELISA method was used, complemented by the Western-blot test. Myelopathy was considered associated with HTLV-1 only when the CSF was positive indicating neurotropism of the virus. The mean age of the cases was 44.6 +/- 15.6 years and the control group was 43.5 +/- 16.0 (p > 0.05). An OR of 9.0 was detected with a reliability interval (95%) of 1.652-48.866 and chi-square significant at the 0.02 level. Despite a strong degree of association and considering the low level of precision, there is a need for analytical studies with larger samples which besides improving the precision will allow for greater control of the confounding variables.

Retinal vasculitis in a mother and her son with human T-lymphotropic virus type 1 associated myelopathy

A 53-year-old woman had difficulty in walking, raised titres to human T-lymphotropic virus type 1 (HTLV-1) in serum and cerebrospinal fluid, and yellowish white retinal lesions and vasculitis in the right eye. Her 20-year-old son also had difficulty in walking, raised titres to HTLV-1 in serum and cerebrospinal fluid, and retinal vasculitis and multiple whitish vitreoretinal spots in both eyes.

HTLV-I associated myelopathy in Porto Alegre (Southern Brazil)

HTLV-I associated myelopathy/tropical spastic paraparesis (TSP/HAM) have been increasingly described in practically all regions of Brazil. Five confirmed and documented cases of patients with TSP/HAM in Rio Grande do Sul are reported; in all of them spastic paraparesis, neurogenic bladder and superficial and/or profound sensitive disorders were observed in variable degrees. One patient presented a relapsing-remitting course with a cerebellar ataxia (multiple sclerosis-like pattern). Everyone was submitted to clinical, serological, urodynamic, neurophysiologic and neuroradiologic investigation. The aim of this study was to present the southern region of Brazil as an area with significant endemicity for HTLV-I/II infection (prevalence of 0.42% between blood donors), and also to show the existence of patients with neurologic disease associated with this retrovirus.

Establishment and characterization of an HTLV-I cell line from a Taiwanese patient with HTLV-I-associated myelopathy

We describe a Taiwanese woman with chronic progressive myelopathy, in whom Western blot analysis of the serum and cerebrospinal fluid (CSF) displayed positive reactions to human T-lymphotropic virus type I (HTLV-I) proteins, p19, p24, p28, p36, gp46 and p53. HTLV-I proviral genomes were detected in the peripheral blood mononuclear cells (PBMC) and CSF cells by nested polymerase chain reaction and Southern blot hybridization. HTLV-I was successfully isolated from PBMC stimulated with interleukin-2 (IL-2). The established cell line, named THAM-1, was an IL-2-independent T-cell line with CD2+, CD3+, CD4+, CD25+ and HLA-DR+. Retrovirus particles with type C morphology were observed in the THAM-1 cells by electron microscopy, and HTLV-I-related antigens were also demonstrated by immunocytochemical staining and Western blot assay. Southern blot analysis revealed that HTLV-I proviral genomes were integrated into the THAM-1 cellular DNA. In Northern blot analysis, two extra-species of RNA were detected in addition to three typical viral transcripts. For the first time, an HTLV-I-producing T cell line was established from a patient with HTLV-I-associated myelopathy in Taiwan, an HTLV-I non-endemic area.

The association of antibodies against human T cell lymphotropic virus type I (HTLV-I) pX gene mutant products with HTLV-I-associated myelopathy/tropical spastic paraparesis

Antibodies specific for the products of the human T cell lymphotropic virus type I (HTLV-I) pX frame-shift mutants were studied by ELISA. The serum IgG antibodies to the synthetic peptide corresponding to one nucleotide insertion at position 7784 were significantly more common in patients with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients than in HTLV-I carriers who had neither HAM/TSP nor adult T cell leukemia (39% vs. 5%). The seropositivities to the other synthetic peptides, which corresponded to the one nucleotide deletion at position 7475 and the internal deletion of nt 7754-7819 and nt 7853-7936, were rare. A genetic study confirmed the presence of the responsible mutation of the pX gene in peripheral blood mononuclear cells and central nervous system tissue from HTLV-I-infected subjects with and without HAM/TSP. These results suggest that HTLV-I pX frame-shift mutants are expressed in vivo in HTLV-I carriers; they also induce antibodies. especially in those with HAM/TSP.

Use of immunoreactive synthetic HTLV-1 peptides in the search for antibody reactivity in multiple sclerosis

The possible association between multiple sclerosis (MS) and antibodies to human T-cell lymphotropic virus type 1 (HTLV-1) was studied. Five synthetic and highly immunoreactive HTLV-1 peptides, four from the envelope (env) region and one from the core (gag) region, were used in an indirect enzyme-linked immunosorbent assay (ELISA). Presence of HTLV-1-specific antibodies in paired serum and cerebrospinal fluid (CSF) samples from 41 MS patients were investigated. No antibody reactivity was demonstrable in samples from 40 of them, whereas one reacted in one serum sample against the gag-peptide. Serum and CSF specimens from 15 with other neurologic diseases (OND), and negative control specimens, i.e. serum and CSF from 9 non-neurologic controls and CSF from 9 healthy controls, did not demonstrate any reactivity in the peptide-ELISAs. Our results do not support involvement of HTLV-1 infection in the etiology of MS.

Inflammatory myopathy on HTLV-I infection: case report

We describe a 41 years old woman who 17 years ago presented hypotonia and proximal muscular weakness in the upper and lower limbs. On neurological examination, the biceps, triceps and Achilles reflexes were absent; the brachioradialis reflexes were decreased and the patellar reflexes were normal. There was bilateral Babinski sign. The remainder of the neurological examination was unremarkable. In the investigation a myopathic pattern was found in the electromyography. The nerve-conduction study was normal; a ELISA method for HTLV-I antibodies was positive in the blood and in the cerebral spinal fluid. The muscle biopsy showed inflammatory myopathy, compatible with polymyositis. This paper focuses the polymyositis in the beginning of an HTLV-I infection case.